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sxmarbury33
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RJ Passenger Concerns After Colgan Crash (Design)

Sat Feb 21, 2009 11:09 pm

Firstly I would like to say that I am not speculating, nor am I hoping to get speculation about the Colgan crash in this thread. The accident just triggered some safety related questions I have been meaning to ask for a while. I'm mainly concerned with CRJ 100/200/700/900's and the old ERJ's. I guess I just find myself dissapointed in some of the modern RJ and Turboprob designers and designs when it comes to safety. Much of this conversation is moot since no one is going to retrofit older CRJ 200's, but I bring these points up for conversation sake. I also would like to point out that I feel safe in today's RJ's but think they could have been designed to be even safer without being cost prohibitive. Posted some of these thoughts in the Colgan thread but never got any response or solid numbers estimates. I don't think a discussion about aviation safety is ever a bad thing and i'd like to get some pilots opinions.


1. Autothrottle/Alpha Floor Protection on RJ's
-I've always wondered this, why do they stick all this technology in CRJ's, ERJ's, Dash q400 etc. and then not equip them with an auto throttle? They have glass cockpits, the best EGPWS, stick shaker and pushers, dont some even have CAT III certified HUDS?, TCAS. The navigation systems are also much more advanced and integreted compared a retrofitted DC-9 32 or whatever NWA is still flying around these days. Even Cessna 172's have glass cockpits now.

How much could it possibly have cost to add A/T to a mordern regional aircraft platform? Airbus dont even have pullys or servos (I forget what they are called), instead they use thrust gates which means it is mostly a software issue. They already have FADC I would assume, how much, literally in doller terms, would autothrottle/alpha floor protection cost? The only major problem I see is that these aircraft aren't FBW. In that case the system could be designed like the 777 and when A/T is armed, but speed controlled manually, the A/T will "wake up" nearing stall speed (yellow bricks), and then add max allowable thrust (red bricks) until the stall is recovered. I can't remember exactly how the 777 system operated but I'm thinking Max thrust until stall is over then Speed hold to 15 knots above the yellow dots on the speed tape or somthing like that so as not to overspeed or cause serious pitch problems. This system would not limit control movements in any way, ie. not full alpha floor protection, so a stall would be able to occur but not at engines idle and without a ton of warning first. I understand FBW technology was expensive at the time CRJ's were designed but A/T technology has been around for decades.

If its an FAA commonality or type rating issue couldnt airlines pull a Southwest and disable the autothrottle/vnav if they wanted say Dash 8-300 commonality. I forget how it works but isnt the 742 and 744 on the same type rating just with sub model specific training? Either way if you can't learn autothrottle and/or VNAV in a 30 hour FAA approved add on course then you have no business flying an aircraft. I guess its good that the new Embraers have autothrottle.




2. No excuse for lack of effective Visual and Aural cues for serious situations
-Why on modern airliners does the aircraft not warn of a possible impending out of trim situation? The major warning should not be an autopilot disconect with trim already to the stops. Why is there not a happy medium between crying wolf all the time like the MD 80's "ehhhhh STABILIZER IN MOTION", which I would imagine desensitizes pilots and a modern system which would really warn of an impending autopilot dissconect.

737's do an ok job with the spinning trim wheels but that is simply not enough. Besides weren't they only kept on the NG for commonality reasons? Is there some type of advanced warning on a 777 that i'm not familliar with? In any case a simple aurual "Trim Limit Approaching" would suffice. Even a yellow caution on eicas would do.




3. Autoland Currency Tests in Bad Weather, SOP?
-Why was the DL 1998 flight going to do an autoland that night? I am pretty sure I heard them say it was for currency reasons. I know they did not ultimatly autoland but wasn't it kind of a bad night to autoland merely for currency reasons anyway?

Max Thrust TO currency fine, but Autoland in that weather. Wasn't it gusting pretty hard? I also forget which direction they were approaching but with the NOTAM about the Glideslope capture it doesnt seem prudent to test the autoland on that ILS. Was the SWA memo for internal use only?




Sorry this is so long but I have one last question pertaining to the Colgan crash and the Dash 8 Q400 specificly. Why do they have a seperate switch to modify the Ref speeds for icing or not. Why could it not have been integrated into the anti-ice system. When the anti-ice is on or auto ref speeds +20, when it is off, ref speeds regular. Why add an extra step that would be easy to forget or miss during high distraction times that has such serious consequenses. Don't they have entire aviation degrees in ergonomics/safety and cockpit design. This would seem like an example of poor design. Am I missing somthing? Are there times anti-ice would be on and you would want regular Ref speeds?
 
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Starlionblue
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Sun Feb 22, 2009 12:14 am

"1. Autothrottle/Alpha Floor Protection on RJ's"

I'll let someone else answer the rest. But you have to separate a/t and alpha floor. Any airliners have the former, but only FBW Airbi have the latter.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
wingscrubber
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Sun Feb 22, 2009 12:21 am

I'm not sure if an autothrottle really gives any safety advantages - the primary use for it is really just long-haul cruise control. Short-haul puddle jumpers shouldn't need it, even if the pilot prefer it for reduced workload, monitoring throttle and trim position are some of the pilots primary responsibilities.
I for one think that it's also the pilots' responsibility to have his hands on the controls during bad weather/potential icing conditions plus it's apparently also policy for Colgan air.
I've done some design ice certification work before where we deliberately compromise the aerodynamics of the test aircraft with simulated impact ice shapes then give it to the test pilots' to take it up and see what it can and can't do. The results of that flight get published in the flight manual; pilots should know what kind of speed margin they should be flying with in icing conditions.
I don't think the Q400 or other similar regional turboprops have any real design flaws, but they do have limitations and suffer performance penalties in bad weather which the pilots must be aware of.
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pilotpip
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Sun Feb 22, 2009 4:17 am

1) Autothrottles aren't a safety feature. They reduce fuel consumption and workload to an extent. In my aircraft they have so much lag that I often turn them off or override them during gusty winds or going into airports with terrain.

2) You have a trim warning of some sort, and the system times out after a couple seconds of activation if doing it manually. Furthermore you have the indication on the trim wheel or EICAS and if your keeping your scan going you have the instruments in view as well. What more do you want? As you approach the stall, you have some sort of pitch limit indication on most glass cockpits, and then the stick shaker/pusher as well as an aural warning.

3) I doubt the Q is capable of auto land. Most RJs aren't. Mine is, but we don't do it. The Glideslope thing is a moot point because it was from the right. Further it's far enough off the localizer that it shouldn't be tracking it yet. In most aircraft the glideslope won't capture if the localizer hasn't been captured.

4) Bugging speeds is a manual thing for safety. This is so the pilots can add a margin for wind gusts to Vapp. Also there in case any systems have malfunctioned so they can be adjusted accordingly. They also vary based on weight. Additionally, the reason that ref speeds are higher is because you are assuming there is ice on the aircraft. Ice will increase the weight as well as decrease the efficiency of the wing. As a result, you have to fly a higher approach speed.

Automation isn't always the answer. In many cases it's the problem. I'm not going to speculate on anything because the NTSB will do a good job as they always do. However I will say that I will never fully "trust" automation. There has been more than one time where I didn't like what it was doing and elected to turn it off and hand fly.
DMI
 
tdscanuck
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Sun Feb 22, 2009 6:32 am



Quoting Sxmarbury33 (Thread starter):
If its an FAA commonality or type rating issue couldnt airlines pull a Southwest and disable the autothrottle/vnav if they wanted say Dash 8-300 commonality.

You can only do that if you have a physical analog throttle linkage, which negates all of the cost/complexity advantages of the Airbus-style gate system. So it's doable, but not on all aircraft without significantly altering the throttle operation.

Quoting Sxmarbury33 (Thread starter):
-Why on modern airliners does the aircraft not warn of a possible impending out of trim situation?

It does, Pilotpip has a good list. Just not with a distinct aural for that specific condition. If this happens enough times they may well introduce a specific aural for it. It generally takes one incidental for the NTSB to ask for it, and 2-3+ for the FAA to actually implement it.

Quoting Sxmarbury33 (Thread starter):
Why do they have a seperate switch to modify the Ref speeds for icing or not. Why could it not have been integrated into the anti-ice system.

You answered it yourself:

Quoting Sxmarbury33 (Thread starter):
Are there times anti-ice would be on and you would want regular Ref speeds

You'll have anti-ice on in any visible moisture at temperatures considerably above where you'd expect icing. You don't want to automatically dial up your reference speeds because, most of the time, you don't want them any higher.

Tom.
 
AirWillie6475
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Sun Feb 22, 2009 11:11 am



Quoting Sxmarbury33 (Thread starter):

1. Autothrottle/Alpha Floor Protection on RJ's

The reason that RJs don't have AT, first because you don't need them, but second they do not have VNAV capability(cost, design). AT is not a safety thing, in fact it will make pilots complacent. It's nice to have for long flights but other than that, I can't think of any reason to have auto throttles. Most Fadec equiped airplanes have gates on the thrust levers, that is kind of like poor mans auto thrust and it does the job fine, all you have to worry about is power on the decent.

Quoting Sxmarbury33 (Thread starter):

2. No excuse for lack of effective Visual and Aural cues for serious situations

I don't know where you got the idea that "modern" airplanes don't warn pilots of trim problems. Virtually every modern cockpit has that feature. Including aural warnings. Also, when an airplane is on AP, the trim will very gradually move, it will not set off any aural warnings even if the wings are iced. The only warning they'll have is that there will be a message that says the airplane is out of trim while it's on AP and they will get that long before it becomes a flight control issue.

Quoting Sxmarbury33 (Thread starter):


3. Autoland Currency Tests in Bad Weather, SOP?

I'm not really sure why that matters. That is the point of Autoland to land in very bad weather with low vis.




Quoting Sxmarbury33 (Thread starter):
Sorry this is so long but I have one last question pertaining to the Colgan crash and the Dash 8 Q400 specificly. Why do they have a seperate switch to modify the Ref speeds for icing or not. Why could it not have been integrated into the anti-ice system. When the anti-ice is on or auto ref speeds +20, when it is off, ref speeds regular. Why add an extra step that would be easy to forget or miss during high distraction times that has such serious consequenses. Don't they have entire aviation degrees in ergonomics/safety and cockpit design. This would seem like an example of poor design. Am I missing somthing? Are there times anti-ice would be on and you would want regular Ref speeds?

It's not as primitive as you think. Most FADEC airplanes will give you the MAX and MIN allowable speeds anyways on the speed tape, despite what you work out on your speed cards. Most of the time when it's gusty or windy, we find that the speeds don't come out in the safety margin with the min flying speed so we actually just use whatever the airplane tells us on the speed tape and we bump the speeds up accordingly. So, it doesn't really matter what speeds you come up with 10,20 plus, the airplane will show you what the min speed is for any given condition on the approach.
 
AirWillie6475
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Sun Feb 22, 2009 11:23 am



Quoting Sxmarbury33 (Thread starter):
The accident just triggered some safety related questions I have been meaning to ask for a while. I'm mainly concerned with CRJ 100/200/700/900's and the old ERJ's

The CRJ and ERJ are as advanced and even more advanced then some narrow and wide body airplanes flying out there. They are incredibly automated. Again they do not have AT but it's not needed at all, it's just a pilot comfort thing. You don't need to be raising any "safety" related questions about these airplanes.
 
AirWillie6475
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Sun Feb 22, 2009 11:34 am



Quoting Sxmarbury33 (Thread starter):



Quoting Sxmarbury33 (Thread starter):
Either way if you can't learn autothrottle and/or VNAV in a 30 hour FAA approved add on course then you have no business flying an aircraft

Hahaha, if you need auto throttles to help you keep your speed on the approach, then YOU have no business flying an aircraft. I've jump eated on the actual airbus cockpit and they literally turn on the AP and the airplane does everything for them. THAT is scary.

Again this is in no way implying that that is what happened for Colgan.
 
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Aaron747
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Sun Feb 22, 2009 1:00 pm



Quoting Pilotpip (Reply 4):
There has been more than one time where I didn't like what it was doing and elected to turn it off and hand fly.

An excellent rule of thumb for all aviators with automation on board. Despite my low time compared to you guys, I can recall a few situations in turbulence or going through shear boundaries that I didn't like what the autopilot in the C-172S was doing either. On a clear day with a lot of other work to do (like spotting traffic or VFR wayfinding), the autopilot is a godsend for single-pilot operation, but in environments where I needed to be completely in sync with the aircraft, hand-flying's the only way to go. I plan to only intensify this mindset with time.
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stratoduck
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RE: RJ Passenger Concerns After Colgan Crash (Desi

Sun Feb 22, 2009 2:02 pm

i used to have the belief similar to this, but over time, i changed my mind a lot. there are times when i know i can fly better than the autopilot, but there are also time when i know it is safer with the autopilot on with my monitoring the actions.

considering the conditions of the colgan flight, i too would have had that autopilot on. it was late, i bet the pilots had been on duty for some time, and it was IFR with icing. let the autopilot join the loc and glide, configure the plane with it on, stabilize the speed, and then click the autopilot off, and it hands you an aircraft all set up for approach and landing. the autopilot lets you focus on monitoring the progress of the flight, and not split your thoughts between flying and monitoring the progress of the flight.

on another post, there was a post on factors for recent rj/commuter crashes. fatigue keeps coming up a lot. that and complacency are two huge enemies for pilots and safety.

in that respect, i do think there is a very notable safety factor for having auto-throttles to reduce workload and fatigue.

an alert pilot is pro-active. an autopilot is re-active, but instantaneously so. i tired pilot reacts, and the length of that reaction is based on such things as scan speed, workload, fatigue, and distractions.

in my mind, a good pilot isn't a pilot with great capabilities as much as it is a pilot that know what his/her limitations are.
 
pilotpip
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Sun Feb 22, 2009 4:27 pm



Quoting Stratoduck (Reply 10):
in my mind, a good pilot isn't a pilot with great capabilities as much as it is a pilot that know what his/her limitations are.

Very well said. Don't get me wrong, the autopilot usually goes on pretty fast if I'm doing an RNAV departure out of ATL because of the complexity and how much is going on. Same going into or out of ORD. However you can never get complacent.

Oh, and as for "recent rj/commuter crashes", the last two accidents prior to Colgan were mainline. In both cases nobody died so apparently they don't count.
DMI
 
avt007
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Sun Feb 22, 2009 8:33 pm

My two cents- The CRJ has trim warnings. One is the "clacker" a noise that sounds when the stab trim moves at a certain speed for a defined period of time. Also there are EICAS trim messages (accompanied by a single chime and master caution lights) to warn of autopilot out of trim conditions.
The CRJ700/900/1000 will probably have an autothrottle option available soon. Bombardier is working on it as a production item, and possibly a retrofit as well.
Autoland (at least for CAT III) is of no use in smaller airports where regional aircraft fly, so that's one major reason not to equip them with it.
 
sxmarbury33
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Mon Feb 23, 2009 6:16 am

Ok, I guess I dont mean they all need to be autothrottle capable. But are any of you familiar with the 777 autothrottle? It will bump the power up when the speed tape gets in the yellow. I think it will go max thrust if the speed tape gets in the red. Why not have a system such as that? What't the point of having a stick pusher and not a throttle pusher as well?

I would compare that system to the AA 757 crash in south america. Before that there was no feature to auto stow the spoilers right? Seemed easy enough to add. I can't imagine any time you would want throttles at idle going into a stall.

Quoting Pilotpip (Reply 3):
2) You have a trim warning of some sort, and the system times out after a couple seconds of activation if doing it manually. Furthermore you have the indication on the trim wheel or EICAS and if your keeping your scan going you have the instruments in view as well. What more do you want?

I don't agree with this attitude. You could say the same thing about CFIT. You have your charts to give you an MSL, ATC to give you altitude clearences, and a radio altimiter on the PFD. What more do you want? Why do you need an EGPWS to keep you out of the ground. I think anything that could make the airplane safer should be added. I am not questioning the day to day safety of any aircraft, I am just trying to raise some areas where I think more can be done.

Quoting AirWillie6475 (Reply 5):
I don't know where you got the idea that "modern" airplanes don't warn pilots of trim problems. Virtually every modern cockpit has that feature. Including aural warnings. Also, when an airplane is on AP, the trim will very gradually move, it will not set off any aural warnings even if the wings are iced. The only warning they'll have is that there will be a message that says the airplane is out of trim while it's on AP and they will get that long before it becomes a flight control issue.

Ok so your saying that most glass cockpit equipped aircraft DO get an EICAS message alerting them that the AP has trimmed to near full? That's good to hear. I can picture this on the 75/76 but does anyone know if the Dash 8 Q400 EICAS would have a similar alert?

Quoting Pilotpip (Reply 3):
3) I doubt the Q is capable of auto land. Most RJs aren't. Mine is, but we don't do it. The Glideslope thing is a moot point because it was from the right. Further it's far enough off the localizer that it shouldn't be tracking it yet. In most aircraft the glideslope won't capture if the localizer hasn't been captured.

I was talking more about the MD88 than the Q. I found it odd they were doing currency autolands in that weather. Is that SOP for most airlines?
 
JoeCanuck
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Mon Feb 23, 2009 7:02 am

I suspect, if it turns out to be a contributing factor, that auto throttles may be recommended.
What the...?
 
CRJ 900
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Mon Feb 23, 2009 12:57 pm

SAFE FLIGHT Auto Power offers a retrofit autothrottle for the CRJ200.
 
pilotpip
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RE: RJ Passenger Concerns After Colgan Crash (Desi

Mon Feb 23, 2009 4:26 pm



Quoting Sxmarbury33 (Reply 12):
I don't agree with this attitude. You could say the same thing about CFIT. You have your charts to give you an MSL, ATC to give you altitude clearences, and a radio altimiter on the PFD. What more do you want? Why do you need an EGPWS to keep you out of the ground. I think anything that could make the airplane safer should be added. I am not questioning the day to day safety of any aircraft, I am just trying to raise some areas where I think more can be done.

No amount of automation will help if you're that disoriented. The Cali crash is a good example of that. While yes, the spoilers were the reason for CFIT, the disorientation was the reason they were even in that situation. Having your charts out and confirming the station freq. and ID would have prevented that situation from ever starting. The key is to stay aware of your surroundings. At some point, the alerts, warnings and system protections are counter productive because you can't make enough sounds and flashing lights.

I never want to encounter an emergency situation in the jet. It will likely happen sometime but even in the sim it's realistic and intense enough that keeping concentration focused on flying the airplane can be difficult with all the warnings going off. Blasting through checklists is a moot point if you crash doing it.

The 170 is a highly automated jet. It is FBW, has envelope protection, Autothrottles and a very good aural and visual warning system. Autoland is installed but we don't use it. For regionals, it doesn't make sense to have CAT III and autoland. We're flying an hour or two at the most. Rather than flying, stay on the ground until the weather goes up or divert. If the airport is that socked in the pax aren't going to miss their connections because they aren't leaving either.

Bottom line, I'm not a fan of the plane thinking for me. The reason I'm not is because I still have to tell it HOW to think and it can't interpolate or improvise. Would you prefer throwing the pilots out of the front and just letting the automation do the job?

It never ceases to amaze me how much higher the standard we are held to is. Busses, trains and your own automobile kill far more people every year than airline crashes. Prior to Colgan it had been years since there was a fatal crash. Given the number of aircraft in the air at any given time that's an incredible statistic on its own. Pilots do a great job, mechanics do a great job, the flight attendants do a great job. You would need many more crashes to make flying anything less than the safest mode of transportation in the modern world.
DMI
 
onetogo
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Mon Feb 23, 2009 6:10 pm



Quoting AirWillie6475 (Reply 5):
but second they do not have VNAV

False.

Quoting AirWillie6475 (Reply 6):
The CRJ and ERJ are as advanced and even more advanced then some narrow and wide body airplanes flying out there. They are incredibly automated.

Correct. Directly contradicting your statement above.

Quoting Pilotpip (Reply 15):
spoilers were the reason for CFIT

The NTSB would disagree with you on this.
 
pilotpip
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Mon Feb 23, 2009 7:02 pm



Quoting Onetogo (Reply 16):
The NTSB would disagree with you on this.

Had the spoilers retracted, the aircraft would have cleared the hill. Of course, had they pulled a chart out and Identified everything to make sure it was right they would have never been in that situation in the first place.
DMI
 
Mir
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Mon Feb 23, 2009 10:57 pm



Quoting Pilotpip (Reply 15):
Having your charts out and confirming the station freq. and ID would have prevented that situation from ever starting.

They did have charts out, and they got the right ID for the station. The problem was that, with the way the database was set up, what they thought was the right input to the FMC was the wrong input. And then they failed to verify the projected course, which would have told them instantly that something wasn't right.

It probably would have helped if they had briefed the approach, too.

-Mir
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tdscanuck
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Tue Feb 24, 2009 2:06 am



Quoting Sxmarbury33 (Reply 12):
But are any of you familiar with the 777 autothrottle? It will bump the power up when the speed tape gets in the yellow.

Yes, it will, if it's armed. It's virtually always armed, even if it's not engaged.

Quoting Sxmarbury33 (Reply 12):
I think it will go max thrust if the speed tape gets in the red.

It might go to max continuous thrust, but I doubt it would go to max takeoff thrust. Not completely sure about that though. If the speed tape hits the read you'll have EICAS warnings, stick shaker, sirens, and a bunch of other fun stuff to tell you that things have gotten bad.

Quoting Sxmarbury33 (Reply 12):
I think anything that could make the airplane safer should be added.

You have to draw the line somewhere. Lots of things that can make an airplane safer aren't added because (typically) it's either "safe enough" for that particular failure mode, or the cost of the fix would grossly outweight the benefit.

Tom.
 
sxmarbury33
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Tue Feb 24, 2009 2:12 am



Quoting Pilotpip (Reply 15):
No amount of automation will help if you're that disoriented.

This is not true. EGPWS would have prevented that accident. Linked to the GPS EGPWS would have provided a ton more warning time since its not linked to the radio altimeter.

Your missing the entire point and getting to caught up in the automation (systems monitor) vs dead stick older style flying.

Quoting Pilotpip (Reply 15):
Bottom line, I'm not a fan of the plane thinking for me. The reason I'm not is because I still have to tell it HOW to think and it can't interpolate or improvise. Would you prefer throwing the pilots out of the front and just letting the automation do the job?

I get what you mean and I agree that to much automation can lead to complacency. The point I am trying to make is that if your letting yourself get into a stall then you arent doing your job and not thinking. VNAV and autothrottle aside, I think more aggressive stall protection should have been added to many of the early CRJ's and ERJ's.
 
pilotpip
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Tue Feb 24, 2009 2:25 am

How many CRJs and ERJs have stalled and fallen out of the sky?
DMI
 
sxmarbury33
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Tue Feb 24, 2009 3:47 am

Not that my suggested system would have saved them but just off the top of my head the pinnacle crj crash.

I am not under the impression CRJ's are stalling left and right, BUT can you guys really not imagine a fatigued pilot of any regional airline after 8 segments in bad weather and crowded terminal approach areas doing the following scenario?

Missed approach at the first airport. ATC then leaves them on the high side and fast descending into the alternate, also told to keep speed up 230 to XYZ. Then told to slow and descend to 3000. Throttle to idle, pilot monitoring is entering new FMC approach data while the PF gets a TCAS caution and is simultaneously told by atc to look in a partiular direction and report in sight. The plane levels at 3000 and both pilots are looking at their 3 oclock for the traffic. Its also dark and the traffic is a tiny cessna with weaker landing lights. Suddenly the stick shaker goes off. PF adds full power and stall is avoided. I dont know about you guys but I can see this happeneing a lot more than it might be reported. Surely some of you RJ pilots have forgot to add power 5-15 seconds after level a level off. Maybe you guys never do but that would really surprise me.

A system on the CRJ would not only give a clue before the stick shaker, it would also have the engines already spooled up somewhat. I doubt spool times on a crj engine are as bad as on a 777 GE90 but it could buy you a lifesaving second or two if the aforementioned stall was in moderate wind sheer. Its usually a combination of factors which lead to an accident.
 
sxmarbury33
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Tue Feb 24, 2009 3:55 am



Quoting Avt007 (Reply 11):

Its good to know that the CRJ has basically the warning system I brought up originally. I assume a Dash 8 Q-400 would have a similar system? Therefore it would be hard for a pilot to let AP trim into a stall and suddenly dissconnect leaving the pilots startled with the stick pusher activating, right? Again, im not trying to speculate, I am just saying hypothetically.

1. "Clacker"
2. Eicas message
3. single chime and master caution lights
4. Stick Shaker
5. Stick pusher (These operate at seperate times I would hope, ie shaker goes off 5 secs before an impending stall... pusher on the brink of stall or somthing like that)
 
tdscanuck
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Tue Feb 24, 2009 6:10 am



Quoting Sxmarbury33 (Reply 20):
This is not true. EGPWS would have prevented that accident.

It might have...unless it actually took control of the airplane, we can't know for sure that it would have prevented it. CFIT almost always involves the crew thinking they know where they are, but being wrong (it's much rarer for them to know they're lost). In that case, the most likely human reaction is to assume the system is screwing up and ignore it. There are plenty of cases of this happening with CFIT, as well as some other warning systems (like the Helios crash). If you think you know what's going on, your natural instinct is to discard data which does not comply with your mental concept.

Quoting Sxmarbury33 (Reply 20):
VNAV and autothrottle aside, I think more aggressive stall protection should have been added to many of the early CRJ's and ERJ's.

A stall, by itself, really isn't that big a deal. The lift doesn't suddenly go to zero and you don't drop out of the sky, the lift just rolls off and your drag goes way up. All commercial aircraft have to be proven to have benign stall recovery characteristics that do not require "unusual pilot skill" to recover from. If you do it too close to the ground, yes, that's a problem, but if you're that close to the ground you should be in a pretty attentive takeoff/approach mindset already.

Tom.
 
pilotpip
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RE: RJ Passenger Concerns After Colgan Crash (Desi

Tue Feb 24, 2009 5:23 pm



Quoting Sxmarbury33 (Reply 22):
Missed approach at the first airport. ATC then leaves them on the high side and fast descending into the alternate, also told to keep speed up 230 to XYZ. Then told to slow and descend to 3000. Throttle to idle, pilot monitoring is entering new FMC approach data while the PF gets a TCAS caution and is simultaneously told by atc to look in a partiular direction and report in sight. The plane levels at 3000 and both pilots are looking at their 3 oclock for the traffic. Its also dark and the traffic is a tiny cessna with weaker landing lights. Suddenly the stick shaker goes off. PF adds full power and stall is avoided. I dont know about you guys but I can see this happeneing a lot more than it might be reported. Surely some of you RJ pilots have forgot to add power 5-15 seconds after level a level off. Maybe you guys never do but that would really surprise me.

I've gone missed exactly 1 time in two years and it was because an aircraft blew a tire in front of us and stayed on the runway. This scenario doesn't happen. Even if it did you're usually pretty alert in the terminal area. This scenario doesn't happen. But if it does, we train for it and stall recovery and RA resolution should be automatic.

You don't seem to understand what TCAS does. If you are close enough for an RA you're going to do what the TCAS says, not ATC.

Stalls aren't avoided with power. They're avoided by exceeding the critical angle of attack. Both RJs I've flown have pitch limit indicators that come down on the PFD and change color as you approach stall. You then have the stick shaker followed by the pusher. Both happen before stall. The 170 has pitch limit protection built into the FBW logic. It won't let you stall unless you override it which is an emergency procedure.

Aircraft aren't stalling and falling out of the sky, they're not running into each other in the air, they aren't crashing on landing because the autoland was inop. I could go on but it seems that you don't want to understand that the systems we already have in place do a very good job.
DMI
 
sxmarbury33
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Tue Feb 24, 2009 6:43 pm



Quoting Pilotpip (Reply 25):
You don't seem to understand what TCAS does.

I wasn't talking about a resolution advisory, just a caution. Traffic Traffic. Let me also say that I am putting the ERJ 170 175 190 195 in a whole different leauge. They are truly world class advanced aircraft and I feel 100% secure on those.

In comparison I think the old CRJ's and ERJ's are a little red headed step childish. Not safety wise but they were just stretched versions of a business jet. The whole package has a sense of rushness and cost competitiveness that the new ERJ's dont have. The new ERJ's compete with F100's, DC9's etc. The CRJ 100/200 was Bombardier's effort to capitilize on the turboprop market with a simple and easy stretch of their existing airframe. Turboprops are cheaper therefore CRJ 200's had to come close to their cost.

I am now at the age where some of my friends are flying these aircraft. I guess that is what scares me on some level. I think back to all those "nights" we used to have. I've seen them zone out, and while I have complete confidence in their skill an aircraft knowledge I am aware that in crowded airspace during chalenging times everyone will be put under stress and make mistakes. Most are caught and discussion ends there. I'm not gonna lie, I feel much safer on a new embraer than on a CRJ. There is no real factual proof to back that up, its just how I feel. And trust me, I am a champion of air safety to my friends. I am always the one telling them how safe it is. I get concerned as a passenger because I know what CAN go wrong given the right circumstances. When I am talking to you guys I am kind of playing devil's advocate.

Quoting Tdscanuck (Reply 24):
It might have...unless it actually took control of the airplane, we can't know for sure that it would have prevented it. CFIT almost always involves the crew thinking they know where they are, but being wrong (it's much rarer for them to know they're lost). In that case, the most likely human reaction is to assume the system is screwing up and ignore it.

First of all you bring up a great point. I still think given the circumstances it would have saved the AA 757. They DID respond to the GPWS warnings if I remember right. I have heard of ghost GPWS warnings during the middle of an ILS approach. Having said that, I would hope that ALL crews immedietly execute an escape maneurver from a EGPWS warning. I once read in the sporty's "I learned about flying from that" about a crew who was doing a visual approach in hilly terrain. They had the ILS tuned but once the field was in sight they ignored it completly. They ended up aimed for a runway at a nearby airport with differnt approach altitudes, no VASI. Suddenly the GPWS went off but they ignored it since they had the field in sight. Right after this the copilot noticed the tops of trees about 200ft lower then the aircraft on a high hill. I dont know if I remember the story 100% but the jist is, follow GPWS warnings even if your on an ILS glideslope at a huge airport. They spend all this time training pilots not to think but to react ie to RA and EGPWS warnings and yet young pilots still THINK instead of ACTING and being on the safe side.

It just seems that most of the pilots here seem to be arguing to keep the status quo. Instead of blindly saying the scenario can't happen why not try and think about stressful situations where stuff could happen. Look at captain sullivan, he studied crashes and probably was always thinking of ways to make aircraft or flying safer no matter how safe the statistics are.

I know pilots are concerned these days with being replaced by a computer but that is just funny talk in my opinion. I think some (certainly not all) pilots are scared of automation for this reason. I had to write a paper a while back (posted a thread) for my public policy class. It could be any topic and I picked ATC. Do you guys know how big of a fight the controllers and other groups are having to put up simply to upgrade their equipment from the 70's. We are at least 50-70 years away from pilotless due to beuracratic hold ups alone. Do you realize the kind of infastructure that would be needed. I think it will never happen in my lifetime because people are just to afraid. To a ton of people statistics dont matter. If they did fear of flying would not exsist. Having said that, I think all of you pilots saying you are perfectly happy with no autothrottle are crazy. I would consider it the next best thing to sliced bread. Like a microwave in college. It's not always perfect and sometimes you need to babysit it but if I flew as a carrer I would give my left nut for one.

On a sidenote, I think a lot of my apprehension to CRJ's is the cockpit layout. I'm so used to the Boeing and to some extent Airbus Glass Cockpits that the CRJ setup seems very different. Has anyone flown both? Is it hard to transition either way? Did you have a preference? CRJ vs boeing/airbus?
 
pilotpip
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Tue Feb 24, 2009 7:03 pm

Your logic is flawed. While the 170 has lots of envelope protection, it's a moot point if you fly the aircraft within it's designed parameters. Aside from that, they all have the same warnings and cautions. Having flown the 145 as well I encourage you to look at the record of that aircraft as well. It's yet to have a hull loss. It's also certified to the same standards that the 170 is. If you look at accident rates, the CRJ is very safe as well.

Automation has made me much more complacent at times than not having it. My apprehension has nothing to do with it taking my job. It does make things easier at times. However there are other times that the extra button pushing results in a decrease in situational awareness. It's also not smart enough to detect a mistake. If you make a mistake, and tell the autopilot to do the wrong thing, it's going to do it until it stops flying.

Last, the 145 isn't a bizjet. It's a turboprop with a different wing and engine.
DMI
 
mandala499
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Tue Feb 24, 2009 7:49 pm



Quoting Sxmarbury33 (Reply 22):
after 8 segments

Lucky 6's the limit where I am! At 1 stage, 1 airline made its crews do 10x 20 min legs per duty.. NASTY !

Quoting Sxmarbury33 (Reply 22):
Missed approach at the first airport. ATC then leaves them on the high side and fast descending into the alternate, also told to keep speed up 230 to XYZ. Then told to slow and descend to 3000. Throttle to idle, pilot monitoring is entering new FMC approach data while the PF gets a TCAS caution and is simultaneously told by atc to look in a partiular direction and report in sight. The plane levels at 3000 and both pilots are looking at their 3 oclock for the traffic. Its also dark and the traffic is a tiny cessna with weaker landing lights. Suddenly the stick shaker goes off. PF adds full power and stall is avoided. I dont know about you guys but I can see this happeneing a lot more than it might be reported. Surely some of you RJ pilots have forgot to add power 5-15 seconds after level a level off. Maybe you guys never do but that would really surprise me.

Not saying you're wrong or right, but to me, the real question is, who's flying the plane when they both looked outside? And that's where the problem is... but what caused the problem? Not the no A/T, it's the ATC.

Quoting Pilotpip (Reply 27):
Last, the 145 isn't a bizjet. It's a turboprop with a different wing and engine.

LOL!!!!!! So true!

Quoting Sxmarbury33 (Reply 26):
Has anyone flown both? Is it hard to transition either way? Did you have a preference? CRJ vs boeing/airbus?

I don't fly, but. to be honest, seeing the CRJ flight deck, I immediately concluded it is an upscaled bizjet... and it is not something I want people to sped 8 legs per duty on...
When losing situational awareness, pray Cumulus Granitus isn't nearby !
 
sxmarbury33
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Tue Feb 24, 2009 8:12 pm



Quoting Pilotpip (Reply 27):
Last, the 145 isn't a bizjet. It's a turboprop with a different wing and engine.

I was talking about the CRJ series. The 145 is based off the EMB 140 right? Thats different , they prob had to do quite a bit of redesigning. The CRJ was stretched from the Biz Jet.

I'n my opinion the 75/76 is the pinnacle of modern aircraft design. It seems timeless, uncluttered and efficient. Add GPS to the IRS's and the 777 autothrottle stall protection and I think it is the perfect balance between pilot control and automation. Pilots aren't scrolling through page after page in their EICAS's, but all the useful information is there.

I guess I will play reverse devil's advocate now. Are there any systems on any airliners that I am overlooking that make that cockpit much more safe than the 75/76? Since the technology has to be cheap how would you feel hypothetically if all CRJ's were retrofitted with 757 cockpits?
 
pilotpip
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Tue Feb 24, 2009 8:42 pm

No, the 135/145 is a stretched 120 with a different wing and turbofans. It's so noisy up front because of the turboprop nose that you can't hear yourself think at 310. There's a reason we wear full headsets in that aircraft. The CRJ was designed from the start to be stretched. It was originally designed as a freight aircraft for FedEx so they could replace their falcons and expand after deregulation. Cargo was deregulated in 75 and there were a ton of 727s available so Fred went in another direction.

I know plenty of people that fly the CRJ on 5 and 6 legs per day with no problem. When you do it every day it's pretty easy to find stuff.

I look at the 75/76 and see a first generation glass cockpit. If you ask me it's way to cluttered and not much of an improvement over round dials. Give me my 5 tube EFIS any day.

Bizjets are often the leaders in cockpit ergonomics because they are constantly refined and improved. They are also the leaders when it comes to safety technologies because most operators aren't worried about equipping a large fleet. A 777 that rolls off the line today is identical to a 777 that rolled off the line 10 years ago because the carrier ordering it wants commonality across the fleet. New aircraft don't come along very often in the airline world. The 787 is the first huge departure in thinking from the current generation that started 20 years ago.
DMI
 
mandala499
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Wed Feb 25, 2009 8:50 pm



Quoting Pilotpip (Reply 30):
No, the 135/145 is a stretched 120 with a different wing and turbofans. It's so noisy up front because of the turboprop nose that you can't hear yourself think at 310.

E120 with a wing and stabilizer developed from the FMA-123...

Quoting Pilotpip (Reply 30):
Bizjets are often the leaders in cockpit ergonomics because they are constantly refined and improved.

That's probably why the CRJ-900ER/NG's flight deck felt like a 20yr old Challenger... of which, it was awesome stuff then... why?

Quoting Pilotpip (Reply 30):
A 777 that rolls off the line today is identical to a 777 that rolled off the line 10 years ago because the carrier ordering it wants commonality across the fleet



Quoting Pilotpip (Reply 30):
I know plenty of people that fly the CRJ on 5 and 6 legs per day with no problem. When you do it every day it's pretty easy to find stuff.

Not doubting that...  Wink I was thinking about 8... any flight deck will probably feel nasty!
When losing situational awareness, pray Cumulus Granitus isn't nearby !
 
sxmarbury33
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Mon Mar 02, 2009 3:25 pm



Quoting AirWillie6475 (Reply 7):
Hahaha, if you need auto throttles to help you keep your speed on the approach, then YOU have no business flying an aircraft. I've jump eated on the actual airbus cockpit and they literally turn on the AP and the airplane does everything for them. THAT is scary.



Quoting Pilotpip (Reply 25):
Aircraft aren't stalling and falling out of the sky, they're not running into each other in the air, they aren't crashing on landing because the autoland was inop. I could go on but it seems that you don't want to understand that the systems we already have in place do a very good job.

Not to be crass but does anyone think that the topic of stall protection should be revisited in light of the Turkish 738 crash? Obviously as with the Colgan crash there is not yet a diffinitive awnser, however it does shed some light on how a crew MIGHT be able to be distracted in the cockpit.

A training flight in my opinion is not 100% SOP. The experienced pilots might be looking for small errors that the traniee is missing and miss the big picture errors that would be caught easily on a normal non training flight. Again, I am not saying this is what happened, just how safety can be improved in the future.

As you can see from some of my posts I have some industry experience which is why I am, at times, a concerned passenger. I am sure a lot of it comes from being a control freak. It DOES make me really nervous when I hear pilots say that they are undistractable in the cockpit and they would never miss a speed decay or level off because I KNOW it happens. I'm not talking about pilots statements on this board, but real life conversations from RJ pilots now (flew Cessnas with them back in the day and SAW them miss things).

I saw firsthand the debate over airbus envelope protection and I can see why a pilot would be concerned with the aircraft potentially limiting his pitch movements in critical situations. I see absolutly no reason however that any modern airliner should be designed without some type of enhanced stall protection system, either full envelope and alpha floor (airbus), or "autothrottle wakeup" (Boeing/777).

A few points and or questions

1. There are many airliners out there currently with autothrottles and no stall protection, only warning, ie. 717, ,737 Classic, 737NG, 744, 757, 767. How much would it cost, and how hard would it be to retrofit a 777 like stall "autothrottle wake up------>TOGA/MAX CONT" mode to these types. Not any type of FBW system, just a config/weight based system. I would imagine older types like the MD-80, DC-9's etc would be cost prohibitive.

2. How many knots above stall speed does the stick shaker activate? Pusher?
What are the spool times from flight idle are popular engine types like the CFM-56, RB-211, GE-90, CF-6? I think the FAR minimum is 8 seconds so I would imagine it would be around 6 seconds for most types. That is a long time going from flight idle. A scenario would be a hot and high approach with flight idle instead of approach idle into a glidslope intercept, distraction, speed decay and stick shaker. Stick shaker being your first major warning, 6 seconds to max thrust would seem like an eternity.

To reiterate, I think the 777 system works as follows, approaching yellow bricks on the PFD auto throttle wakes up, approaching red bricks max continious thrust is commanded. If this is wrong let me know. If I had to design it, it would be the same except after the stall is recovered the system would go to speed hold top of the yellow bricks +20 IAS. Everyone is familiar with the term bricks right?

If you are about to reply, "that would never happen to me, I am 100% vigilant and alert during critical phases of flight", would you instead tell me if you would actually be against the proposed enhanced stall protection system in the paragraph above.
 
JoeCanuck
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Mon Mar 02, 2009 7:29 pm



Quoting Sxmarbury33 (Reply 32):
2. How many knots above stall speed does the stick shaker activate? Pusher?

I believe that the stick shaker/pusher initiation is based primarily on angle of attack, not airspeed. While the stall speed will change with a change in weight, the angle of attack where a stall will occur will always remain the same.

That is provided that the airfoil shape hasn't been changed by ice, for instance.
What the...?
 
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Starlionblue
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Mon Mar 02, 2009 11:41 pm



Quoting Sxmarbury33 (Reply 32):
Not to be crass but does anyone think that the topic of stall protection should be revisited in light of the Turkish 738 crash?

Not really. There are tens of thousands of safe airliner flights a day. There are perhaps 2-3 serious airliner crashes per year. Of those crashes, a very small fraction are due to stalls (and in any case stalls are not really a root cause). If stalls were a serious issue they would happen more often.

There can always be improvements to the already stellar safety record. However, a discovery of actual causes followed by recommendations about how to avoid said causes in the future makes more sense than a blunt approach like "let's implement automated stall protection".
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
pilotpip
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Tue Mar 03, 2009 5:46 am

How many years and how many crashes did it take for the FAA and others to require modification to the 737 rudder after all the hard overs?

There's your answer. When people start dying on a regular basis the regulators will require it. Until then it costs too much.
DMI
 
JoeCanuck
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Tue Mar 03, 2009 6:38 am



Quoting Pilotpip (Reply 35):
There's your answer. When people start dying on a regular basis the regulators will require it. Until then it costs too much.

The 737 rudder wasn't a regulation problem...they couldn't find the problem. They tried for years to get the actuator to fail in the lab but couldn't. There was also no damage or marking on the actuator to indicate it failed.

Even when a 737 survived a rudder hard over where they could debrief the crew and test the plane, investigators still couldn't discover the problem, though they learned the symptoms.

It wasn't until some brainiac thought to cool an actuator using liquid nitrogen then actuating it with hot fluid did it eventually fail during testing.

It's not like the DC-10 where they knew about the baggage door and failed to act. They just couldn't find out what was wrong with the 737.

When the did find out, they fixed it.
What the...?
 
sxmarbury33
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Tue Mar 03, 2009 7:50 pm



Quoting Starlionblue (Reply 34):
If stalls were a serious issue they would happen more often.

This doesnt make any sense. Is traffic avoidance not a serious issue? Not to many mid air jetliner collisions in the recent years.

Quoting Starlionblue (Reply 34):
There are perhaps 2-3 serious airliner crashes per year. Of those crashes, a very small fraction are due to stalls (and in any case stalls are not really a root cause).

Again, makes no sense. I'd like to see you tell that to the families of the crash victems. How is a stall not a root cause. If an aircraft is stalled and subsequently crashed how would the stall not be a root cause. Lack of airflow over the wing leading to loss of lift. It doesnt get much more root than that.

Quoting Starlionblue (Reply 34):
However, a discovery of actual causes followed by recommendations about how to avoid said causes in the future makes more sense than a blunt approach like "let's implement automated stall protection".

We already know the main causes of stalls. It's almost always pilot error or wind related. Additionally, pilots are trained from day one to avoid stalls. A recomendation on how to avoid stalls would be that pilots shouldnt get distracted. But we all know pilots WILL get distracted no matter how much they are trained.

Are you REALLY actually against the "blunt" approach or are you just playing devil's advocate/ against change? Out of curiousity would you feel safer on a plane without TCAS and EGPWS? If no, I dont see how "automated stall protection" would be different. If yes, I just don't really know what to say.
 
PhilSquares
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Tue Mar 03, 2009 8:38 pm



Quoting Sxmarbury33 (Reply 32):
A training flight in my opinion is not 100% SOP.

Pardon my bluntness, but why not?

Quoting Sxmarbury33 (Reply 32):
As you can see from some of my posts I have some industry experience which is why I am, at times, a concerned passenger

I can't see from any of your posts you have any experience in the airline at all!

Air travel could be made 100% safe. Tickets would cost several times what they do now, and people would refuse to travel. Air safety is about risk management, that is how to optimize the cost of safety vs. the reality of a crash. There could be billions of dollars invested in aircraft design to ensure no aircraft ever stalled. But, the incremental cost of increasing the safety of the travelling public would be a very dubious investment. Aircraft would be beyond the reach of any airline to purchase.

While I appreciate your desire, you don't have a clue! Betting back to the very first post I quoted, why shouldn't a training flight be SOP 100%? I would argue that most line flights aren't 100% SOP because of the non-training atmosphere. But, more importantly, no flight, training or line is 100% SOP. It's a very naive expectation. Sure, everyone should strive for 100% compliance but it's never going to happen. So, what you have is the need and desire to concentrate on critical areas. That's where you get the biggest bang for the buck.

The bottom line in the airline industry is making a profit. You asked for a response on installing auto throttles in aircraft. The simple fact is it's cost prohibitive. Airlines would rather settle accidents on a case by case basis rather in investing new technology in old aircraft. It doesn't make economic sense to do anything else.
Fly fast, live slow
 
ThePinnacleKid
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Tue Mar 03, 2009 11:24 pm



Quoting Sxmarbury33 (Reply 37):
Lack of airflow over the wing leading to loss of lift. It doesnt get much more root than that.



Quoting Sxmarbury33 (Reply 37):
We already know the main causes of stalls. It's almost always pilot error or wind related. Additionally, pilots are trained from day one to avoid stalls.

Fundamentally wrong on many levels...

1) Pilots aren't trained to avoid stalls, they are taught to recognize the sequence of events that lead up to stalls, the stall characteristics themselves, and proper recovery techniques. That said, learn to fly a Cessna 172.. proper landings are in a fully stalled state... *unlike jet airliners*

2) Stalls have nothing to do with "lack of airflow over the wing leading to loss of lift." A stall is: a condition in aerodynamics and aviation where the angle between the wing's chord line and the relative incoming wind (the angle of attack) increases beyond a certain point such that the lift begins to decrease. The angle at which this occurs is called the critical angle of attack. This critical angle is dependent upon the profile of the wing, its planform, and its aspect ratio but is typically in the range of 8 to 20 degrees relative to the incoming wind for most subsonic airfoils. The critical angle of attack is the angle of attack on the lift coefficient versus angle-of-attack curve at which the maximum lift coefficient occurs, and it usually represents the boundary between the wing's linear and nonlinear airflow regimes. Flow separation begins to occur at this point, decreasing lift, increasing drag, and changing the wing's center of pressure.

In other words... a stall can occur at ANY altitude and ANY airspeed... all a stall comprises is exceeding the Critical Angle of Attack.
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Starlionblue
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Tue Mar 03, 2009 11:43 pm



Quoting Sxmarbury33 (Reply 37):
Quoting Starlionblue (Reply 34):
There are perhaps 2-3 serious airliner crashes per year. Of those crashes, a very small fraction are due to stalls (and in any case stalls are not really a root cause).

Again, makes no sense. I'd like to see you tell that to the families of the crash victems. How is a stall not a root cause. If an aircraft is stalled and subsequently crashed how would the stall not be a root cause. Lack of airflow over the wing leading to loss of lift. It doesnt get much more root than that.

Stall was not the root cause. Stalls don't just "happen". The root cause was the pilot making errors and/or the aircraft malfunctioning and/or an atmospheric phenomenon.

My point is that one should figure out what happened in this case, and if necessary address the issue. Whether automated stall recovery would have prevented this accident is a complete unknown at this point. If it is found that automated stall recovery could have prevented this accident, I'm all for investigating implementation scenarios. I think it will be found, though, that other, much cheaper and easier to implement measures would also have prevented the accident.

However, all the other pilots on all the other flights seem to have little difficulty keeping their aircraft from stalling. It is a well known phenomenon. I am not a pilot but as I understand it speed monitoring is a pretty big part of the job on approach.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
KAUSpilot
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Wed Mar 04, 2009 12:46 am

I would not be overly concerned about inadvertant stalls, on the ERJ's I fly at least. There are many safety features (low speed awarness tape, airspeed trend vector, pitch limit indicator, and of course stick shaker and stick pusher w/ continuous chime). The only part that gets tricky sometims is the phase of flight just prior to slection of maximum flaps. At heavy weights there may only be about a 10 knot difference betwee Vfe (max flap speed) and Vref. That's a pretty narrow speed window to navigate, especially in turbulent conditions, and icing only exacerbates the problem (angles of attack triggering stall protection are automatically lowered if ice has beeen encountered during the flight).

Speed control is of paramount importance during all phases of flight, but especially during an approach and landing. It takes no backseat to lateral and vertical control. Pesonally I've never had the shaker go off on any of my flights and hopefully never will.

Quoting Sxmarbury33 (Reply 32):
2. How many knots above stall speed does the stick shaker activate? Pusher?
What are the spool times from flight idle are popular engine types like the CFM-56, RB-211, GE-90, CF-6? I think the FAR minimum is 8 seconds so I would imagine it would be around 6 seconds for most types. That is a long time going from flight idle. A scenario would be a hot and high approach with flight idle instead of approach idle into a glidslope intercept, distraction, speed decay and stick shaker. Stick shaker being your first major warning, 6 seconds to max thrust would seem like an eternity.

In the ERJ, the stick shaker is activated when your airspeed is 1.13 x the stalling speed in your current configuration, the pusher is activated at stalling speed. On the RR AE3007 series, the manual simply states: (flight idle is calculated in order to) Enable the FADEC to accelerate the engine from Flight Idle Thrust to 100% of the Go-around thrust mode in 8 seconds or less, at or below 9500 ft.

In my experience, it seems much quicker than that (the compressor variable geometry is quite good), but I can't recall a circumstance in which I've actually tested it.
 
sxmarbury33
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Wed Mar 04, 2009 2:12 am



Quoting KAUSpilot (Reply 41):
I would not be overly concerned about inadvertant stalls

Hahaha, dont worry, I'm not anymore. I'm now much more concerned that some of these guys are potentially flying me around.

Quoting ThePinnacleKid (Reply 39):
1) Pilots aren't trained to avoid stalls, they are taught to recognize the sequence of events that lead up to stalls, the stall characteristics themselves, and proper recovery techniques. That said, learn to fly a Cessna 172.. proper landings are in a fully stalled state...

Irony aside, it's good to see you and Pinnacle have intensive stall training now. I do fly 172's and I just don't know what to say. I would call recognizing the sequence leading up to stalls, "avoiding stalls". They go hand in hand.

Quoting ThePinnacleKid (Reply 39):
That said, learn to fly a Cessna 172.. proper landings are in a fully stalled state... *unlike jet airliners*

This is the fundamental problem I have with CRJ and ERJ pilots. Why would you even compare a T-tail regional jet to a cessna 172. Today they are taking kids from cessna's to some light twin and then sticking them in highly advanced and automated flightdecks. Compounding the problem is the intermediete step of flying turboprop is being eliminated. Its like giving a 16 year old an M5 right after he gets his lisence.

Quoting PhilSquares (Reply 38):
There could be billions of dollars invested in aircraft design to ensure no aircraft ever stalled. But, the incremental cost of increasing the safety of the travelling public would be a very dubious investment. Aircraft would be beyond the reach of any airline to purchase.

Are you living under a rock? I hate to break it to you buddy, but billions of dollars do not need to be spent, the technology is already installed in a large percentage of the commercial airliners out there today. Every Airbus minus the 300 and I think the 310. Last I checked the airlines were buying all models of airbus and 777's so I don't know where you come to the conclusion that they are beyond their reach. Someone else said even the new ERJ's have alpha floor and envelope protection. I guess Boeing, Airbus and Embraer dont share your viewpoint.

Quoting PhilSquares (Reply 38):
I would argue that most line flights aren't 100% SOP because of the non-training atmosphere.

Look, i'd agree with you there. In my previous post I was making reference to the fact that the training pilot might be hypersensitive to the more common and subtle mistakes that a training pilot could make and miss somthing much more important.

Quoting PhilSquares (Reply 38):
So, what you have is the need and desire to concentrate on critical areas. That's where you get the biggest bang for the buck.

I would say accidently stalling on approach would be a "critical area" to concentrate on. As KAUS pilot pointed out it takes 8 seconds to spool from flight idle. I don't care how you stall, pilot error, weather, some other phenomonon, I would gladly take an autothrottle that has already bumped up to say 70 n1.

Quoting PhilSquares (Reply 38):
The bottom line in the airline industry is making a profit.

You guys don't seem to be doing that great of a job of it. Due respect, do you really fly the 744 and A320? I'd also argue that autothrottles do have some cost saving benefits. Cost Index etc.. Just like retrofitting blended winglets its not a 100% gaurentee for savings but can and will under the right circumstances.

Out of the few quoted here the only pilot I would feel safe flying with is KAUS.

Frankly, I'd rather see the stick pusher eliminated in favor of autothrottle stall protection. I'd not like a severe push on approach thanks. I'm not even arguing for full envelope protection anymore, now I am just baffled why you guys are so adamendtly against making the stall protection on aircraft better. It's a natural progression. One that is actually employed on a ton of commercial aircraft and some of you pilots are still saying everything if fine the way it is. "Who cares about a crash here or there, as long as there arent too many."

My old car did not have Traction Control or Stability Control. My new car does and I feel safer drving on wet roads. The car is very overpowered but the stability control system comes on aggresivly if any type of slip is detected. What used to be a system only found on luxury cars is now avail on a wide variety of mid priced cars and suv's.

In summary,

Eyes-----> GPWS --------> EGPWS

See and avoid ------>TCAS ---------> TCAS II

Those transitions seemed to go pretty smoothly. I'm not talking about a 9 engine jet with a auto deploy RAT which doubles as a emergency rocket engine. What I have suggested seems well within the realm of decent cost/ benefit. Hell you could probably get an insurance write off.
 
ThePinnacleKid
Posts: 540
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Wed Mar 04, 2009 4:19 am



Quoting Sxmarbury33 (Reply 42):
Irony aside, it's good to see you and Pinnacle have intensive stall training now. I do fly 172's and I just don't know what to say. I would call recognizing the sequence leading up to stalls, "avoiding stalls". They go hand in hand.

dude... read my profile... I don't fly for Pinnacle... I fly the ERJ. You know what they say about assuming.

Quoting Sxmarbury33 (Reply 42):
This is the fundamental problem I have with CRJ and ERJ pilots. Why would you even compare a T-tail regional jet to a cessna 172. Today they are taking kids from cessna's to some light twin and then sticking them in highly advanced and automated flightdecks. Compounding the problem is the intermediete step of flying turboprop is being eliminated. Its like giving a 16 year old an M5 right after he gets his lisence.

because you said that pilots are taught to avoid stalls... No they aren't... they are taught to appreciate/recognize/correct stalls depending on situation... flying the cessna's you do stall on landing.. hardly avoiding one... That said, I even said, it is nothing like a jet. Furthermore, since you only fly a 172 and have yet to ever see first hand what our aircraft are capable of, what makes you think you can't trust what all of us pilots on here flying airliners are trying to tell you???

Quoting Sxmarbury33 (Reply 42):
Compounding the problem is the intermediete step of flying turboprop is being eliminated.

It was only an intermediate step because it was common progression of an era in regional flying... nothing says a turboprop prepares you for a jet... and vice-versa...


I'll further go out on a limb and even say, unlike you who seem concerned about us real world airline pilots flying you around (except KAUS, congrats to him for winning your selection criteria)... I would gladly get on any aircraft that is being worked by Pilotpip, KAUSpilot, AirWillie6475, and the rest...and I would venture to say that I bet most of them would be willing to ride along on one of the flights I'm working.... if you chose not to, well... so be it... I won't lose sleep over it.


btw, my original post was to simply point out to you, that while you keep going on and on and on about the need for better stall protection, you don't even know what a stall is (at least you're not stating it here like you have a comprehension of it)... hence why I provided you the definition of it........ so how can you get so bent out of shape about a phenomenon you don't even understand?
"Sonny, did we land? or were we shot down?"
 
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Starlionblue
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Wed Mar 04, 2009 4:23 am



Quoting Sxmarbury33 (Reply 42):
I do fly 172's and I just don't know what to say. I would call recognizing the sequence leading up to stalls, "avoiding stalls". They go hand in hand.

So, you fly 172s? I submit that this is quite different from flying airliners.

Quoting Sxmarbury33 (Reply 42):
Quoting PhilSquares (Reply 38):
There could be billions of dollars invested in aircraft design to ensure no aircraft ever stalled. But, the incremental cost of increasing the safety of the travelling public would be a very dubious investment. Aircraft would be beyond the reach of any airline to purchase.

Are you living under a rock? I hate to break it to you buddy, but billions of dollars do not need to be spent, the technology is already installed in a large percentage of the commercial airliners out there today. Every Airbus minus the 300 and I think the 310. Last I checked the airlines were buying all models of airbus and 777's so I don't know where you come to the conclusion that they are beyond their reach. Someone else said even the new ERJ's have alpha floor and envelope protection. I guess Boeing, Airbus and Embraer dont share your viewpoint.

You're accusing Captain Squares of not knowing what he is talking about? I don't know whether to laugh or cry.

We will probably see increasing stall protection in the future, but a lot of airliners are flying safely today without it. The point being that if the stall protection systems have to activate the pilots are screwing up by the numbers already.

Quoting Sxmarbury33 (Reply 42):
My old car did not have Traction Control or Stability Control. My new car does and I feel safer drving on wet roads. The car is very overpowered but the stability control system comes on aggresivly if any type of slip is detected. What used to be a system only found on luxury cars is now avail on a wide variety of mid priced cars and suv's.

The equivalent of driving a car aggressively, forcing the TCS and SCS to come into play, would be flying recklessly outside of accepted procedures. Frowned upon to say the least.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
PhilSquares
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Wed Mar 04, 2009 4:40 am



Quoting Sxmarbury33 (Reply 42):
You guys don't seem to be doing that great of a job of it. Due respect, do you really fly the 744 and A320? I'd also argue that autothrottles do have some cost saving benefits. Cost Index etc.. Just like retrofitting blended winglets its not a 100% gaurentee for savings but can and will under the right circumstances.

Sorry, but my sentence should have read the "bottom line was the goal was to make a profit.". As far as my career goes I suggest you back off on your snide comments and concentrate on trying to construct a logical argument on the topic you raised.

I am not stating that autothrottles don't have cost savings benefits, or automation has cost savings benefits, but the simple fact is it's expensive to retrofit certain things on aircraft and in most cases the cost outweigh the savings. On the 744, you can be disptached with the entire autothrottle system inop. So, what about that? Are you suggesting the MEL/MMEL be changed to ground the aircraft if the autothrottles aren't working.

You seem to be focusing in on minor things like the stall. If you look at the number of commercial flights in the US alone on a daily basis and the number of accidents/incidents which are directly related to stalling the aircraft you will find the number in miniscule.

Quoting Sxmarbury33 (Reply 42):
Look, i'd agree with you there. In my previous post I was making reference to the fact that the training pilot might be hypersensitive to the more common and subtle mistakes that a training pilot could make and miss somthing much more important.

I would suggest you don't have a clue! I am a training Captain and I focus on the "big picture" and for me the first and most important thing is the pilot is safe. I think you are somewhat confused on just what's involved in training. As long as the pilot is complying with the SOPs and operating in a safe manner then everything falls into the area of technique.

Quoting Sxmarbury33 (Reply 42):
I would say accidently stalling on approach would be a "critical area" to concentrate on. As KAUS pilot pointed out it takes 8 seconds to spool from flight idle. I don't care how you stall, pilot error, weather, some other phenomonon, I would gladly take an autothrottle that has already bumped up to say 70 n1.

You seem to enjoy quoting posts out of context, I suggest you go back and read my entire post. But, I will attempt to give you an answer you can understand. How many commercial accidents have been caused by stalling on approach? Look at the data.

Putting an autothrottle system on an old technology aircraft would not prevent a stall. If the control surfaces become iced up the stall characteristics change. In some cases you could apply GA power and still have an uncontrollable aircraft, how is that going to help? I suggest we, as a profession, need to look more at preventing the aircraft from getting into the icing conditions in the first place. Better ice detection technology, better anti-ice/deice protection.

Quoting Sxmarbury33 (Reply 42):
Are you living under a rock? I hate to break it to you buddy, but billions of dollars do not need to be spent, the technology is already installed in a large percentage of the commercial airliners out there today. Every Airbus minus the 300 and I think the 310. Last I checked the airlines were buying all models of airbus and 777's so I don't know where you come to the conclusion that they are beyond their reach. Someone else said even the new ERJ's have alpha floor and envelope protection. I guess Boeing, Airbus and Embraer dont share your viewpoint.

First of all, I'm not your "buddy", so don't make that assumption and I don't live under a rock either. Apparently, you do since you keep referring to things you don't have a clue about. My post was in relation to installing automated systems in aircraft that don't have it installed. How do you jump to talking about aircaft that are being ordered now.

The things you are asking for exist in the aircraft I am currentl flying. They are 10 years old and have the latest things available. I am confused as to what just what you are trying to make an issue of.
Fly fast, live slow
 
KAUSpilot
Posts: 1685
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Wed Mar 04, 2009 4:53 am



Quoting Sxmarbury33 (Reply 42):
Frankly, I'd rather see the stick pusher eliminated in favor of autothrottle stall protection. I'd not like a severe push on approach thanks. I'm not even arguing for full envelope protection anymore, now I am just baffled why you guys are so adamendtly against making the stall protection on aircraft better. It's a natural progression. One that is actually employed on a ton of commercial aircraft and some of you pilots are still saying everything if fine the way it is. "Who cares about a crash here or there, as long as there arent too many."

One reason you would probably never see the shaker/pusher eliminated is the loss of all engines scenario. Our stall protection remains operative (from battery power) even with all engines and electrical generators not operative. Auto-throttle type stall protection would obviously not be effective in such a condition.

Thanks for picking me over philsquares btw. I'm sure he will get a kick out of that.

PS (off topic): PhilSquares, I don't know if you remember our old discussion, but we've adopted CDFA non precision approaches at my operator in the past year, so you can feel safe flying on us now, hooray! Unfortunately they are only to be used during weather conditions with at least a few hundred feet and 1/2 mile vis above minimums to spare, as the derived decision altitude has to be 75 feet above the MDA (to accomodate altitude loss during a go-around). So, we are still authorized to do the ol' chop and drop (if that's what you want to call a 1200 fpm descent), ironically in the poorest weather conditions.  Smile
 
atct
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Wed Mar 04, 2009 5:01 am



Quoting Sxmarbury33 (Reply 12):
. Is that SOP for most airlines?

Yes. As a controller at an airport with many CAT III ILS approaches I get requests for autolands in all sorts of weather for currency issues.

ATCT
Trikes are for kids!
 
KAUSpilot
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Wed Mar 04, 2009 5:57 am



Quoting KAUSpilot (Reply 46):
One reason you would probably never see the shaker/pusher eliminated is the loss of all engines scenario. Our stall protection remains operative (from battery power) even with all engines and electrical generators not operative. Auto-throttle type stall protection would obviously not be effective in such a condition.

Just a minor correction to this for clarification, the ERJ has the shaker but not the pusher in the above scenario, fwiw.
 
Soku39
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RE: RJ Passenger Concerns After Colgan Crash (Design)

Wed Mar 04, 2009 6:03 am

After reading through this, Sxmarbury33, it seems likely that you will not be convinced that regional jets, and turboprops are safe... this leaves you one option... simply don't fly, and if you do, get on a mainline ship, good luck doing that in the United States.
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