## Search found 3919 matches

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Sat Jun 08, 2019 4:51 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

What you're showing in this example is the rate of force decrease, d^2F/da^2. I am referring to fig. 7.2 in AC 25-7D where "acceptable" curve (vs speed) shows that exact behavior - decrease of derivative to zero at the edge. You interpret such behavior (vs AoA) as unacceptable. So where d...

Sat Jun 08, 2019 4:10 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

The adaptive cruse control is yet again a dismal comparison. If the cruse control would accelerate on the failure off one sensor, you would have a comparison. On the failure of the cruise control, nothing hinders you to brake yourself. The car is not actively trying to kill you and your passengers....

Sat Jun 08, 2019 4:02 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

I've seen a report a couple of weeks ago suggesting the warning light would have allowed the Ethiopian pilots to recognise and identify their problem earlier If that's true then it's end of argument about whether or not it would have helped them. Do you have a source for the suggestion? I'm curious...

Sat Jun 08, 2019 3:57 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

My apologies, but is there a specific reference for these interpretations? Our beloved 25-7 has graphs only for force vs speed, and all your examples would be acceptable if AoA is interpreted as "AoA required at given speed". Gradient as dF/dx doesn't change sign in your examples, and I d...

Sat Jun 08, 2019 3:05 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

I've seen a report a couple of weeks ago suggesting the warning light would have allowed the Ethiopian pilots to recognise and identify their problem earlier If that's true then it's end of argument about whether or not it would have helped them. Do you have a source for the suggestion? I'm curious...

Sat Jun 08, 2019 2:57 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

But how many other commercial planes would even test pilot skills in this way? How many other commercial planes would try and crash themselves? Any commercial airplane that has a runaway stab trim and the crew does not deal with it correctly. It means it has the potential to crash if you don't deal...

Sat Jun 08, 2019 2:31 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

I've seen it suggested that enlarging the h. stab would solve the problem. This isn't the case. I assume the limiting case/configuration is the stab trim at nose up limit of trim switch, and the righting moment versus AOA curve as the elevator is used to enter a stall according to the parameters of...

Sat Jun 08, 2019 2:22 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

The intent is to obtain enough data to determine the stall speed at an entry rate not exceeding 1.0 knot/second. I take it that means a deceleration of less than 1.0 knot/second to stall, during which the control pressure must increase. So the righting force curve went flat or up on the MAX in this...

Fri Jun 07, 2019 7:00 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

Not a designer or engineer, so correct me if I am wrong.. From some of what I have read I get the impression that adjusting the stabiliser design would help resolve the problems that sparked the genesis of MCAS. Would that take months or would it be years? If an airworthiness certificate is refused...

Fri Jun 07, 2019 5:47 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

What do you thing about the term "death trap"? Is it appropriate for discussions on this thread? We need some words to talk about dangerous things and we cannot ban all of them. Now that you specifically asked I could use that word to describe the condition of the plane after the first Li...

Fri Jun 07, 2019 3:06 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

A simple question: Do you think Boeing set out to kill people by creating the 737 MAX? What asinine question. Of course not. That was the whole point. NObody has set out to kill anybody. It was the point I was trying to make that the word kill is totally 1000% inappropriate to be used anywhere in t...

Fri Jun 07, 2019 2:52 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

Then you've missed the replies that say Boeing caused the MAX to be a "Death Trap". Over the top language has been the hallmark rather the exception for this thread. Your over the top language tries to conflate two very different things. Killing people is a crime and those who kill people...

Fri Jun 07, 2019 1:14 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

People still fly with airlines that have crashed planes and killed far more people than the two Max crashes . One more issue in a way you talk. I haven't seen anybody say in any of these threads that Boeing have killed anybody, but here you talk about airlines that have killed people. Not good. I g...

Thu Jun 06, 2019 12:54 pm
Forum: Civil Aviation
Topic: More safety issues for Boeing...
Replies: 37
Views: 6001

### Re: More safety issues for Boeing...

Polot wrote:
In your first post you mentioned SBs. You are aware most service bulletins are drafted in response to an AD correct? It’s basically telling you how to best rectify and meet the AD.

Usually, an Alert SB is issued first by the OEM and the FAA turns the ASB into an AD.

Sun Jun 02, 2019 9:03 pm
Forum: Civil Aviation
Topic: Has grandfathering been taken too far?
Replies: 362
Views: 19072

### Re: Has grandfathering been taken too far?

GalaxyFlyer wrote:
No, it reinforces the fact that humor is lacking in the dull and overly serious.

GF

Sun Jun 02, 2019 7:45 pm
Forum: Civil Aviation
Topic: Has grandfathering been taken too far?
Replies: 362
Views: 19072

### Re: Has grandfathering been taken too far?

with fire raging behind

Yes, a fire would add an incentive.

Sun Jun 02, 2019 6:18 pm
Forum: Civil Aviation
Topic: Has grandfathering been taken too far?
Replies: 362
Views: 19072

### Re: Has grandfathering been taken too far?

Which just happens to let the 737 squeak in. No one is going to jump six feet with any safety. I'd be lucky to jump two feet. Exactly. When I was a kid, jumping from 10' wasn't a problem. Now I'm 53 and I guess I could jump the 6' without problems. But I doubt I'll be able to do that when I'm 73. W...

Sun Jun 02, 2019 1:58 pm
Forum: Civil Aviation
Topic: Has grandfathering been taken too far?
Replies: 362
Views: 19072

### Re: Has grandfathering been taken too far?

From my understanding you need to certify anything new. New variant of the aircraft or not. However Boeing doesn't need to certify the complete aircraft anew, if it's grandfathered. So the new wings, new engines, etc., get a full certification regime, but not the completed aircraft. That's exactly ...

Sun Jun 02, 2019 12:10 pm
Forum: Civil Aviation
Topic: Has grandfathering been taken too far?
Replies: 362
Views: 19072

### Re: Boeing 777-8/-9 Grandfathering Certification, 777X or 7X7?

So unlike the MAX, the X is a new aircraft, with full new model testing, no exemptions (in full or part) to the latest regulations, and no grandfathering? As has been explained many times in this thread, any new regulations apply only if the part has been changed. There may be many unchanged parts,...

Sat Jun 01, 2019 5:38 pm
Forum: Civil Aviation
Topic: Has grandfathering been taken too far?
Replies: 362
Views: 19072

### Re: Boeing 777-8/-9 Grandfathering Certification, 777X or 7X7?

This doesn't mean you don't have to test the changed area. The new 777X wing will be required to pass a fatigue test and a structural load test to be certified but that certification may need only pass unchanged parts of the regulations that were in force during the original certification basis. Or...

Sat Jun 01, 2019 2:30 pm
Forum: Civil Aviation
Topic: Has grandfathering been taken too far?
Replies: 362
Views: 19072

### Re: Has grandfathering been taken too far?

The basic 737 frame has proven over many years to be tough and reliable. Anything that has come to light has been remedied. One thing that does strike me, though. No overwing emergency exit slides. https://www.standard.co.uk/news/world/passengers-injured-in-scramble-to-flee-after-man-makes-bomb-thr...

Wed May 29, 2019 2:58 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

I haven' read all the posts here so I don't know if anyone has linked this already about "Could US pilots have saved the 737 MAX8 ?" https://www.youtube.com/watch?v=ZtHBz2-YpWE Thanks, but already posted. Of course, the simulation starts with the horizontal stabilizer electric motor switc...

Mon May 27, 2019 9:53 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

I cant agree that complying with 671 will relieve anyone from complying with 1309.... Cheers To carry on with 7BOEING7's point about the FAA interpretation of MCAS 1.0, the single sensor failure with regard to MCAS operation was always present. Under MCAS 1.0 certification, a single AoA vane signal...

Mon May 27, 2019 7:35 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

-Cannot obtain meaningful voting on the validity of the data source, it is either OP or INOP. -Cannot achieve failure rate (typ 10^-9) for critical flight control components and thus probability vs severity wrt stalling and departure from controlled flight. -Without it aircraft is still uncertifiab...

Mon May 27, 2019 12:33 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

ExperimentalFTE wrote:
I personally think that with current hardware configuration functionality you mention for MCAS 2.0 is as uncertifiable as it gets.

Please explain why you think that MCAS 2.0 as described is not certifiable.

Sun May 26, 2019 9:44 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

I'd like to post my summary of what I think the key issues are - and to debunk some of what I see as the most common misconceptions presented: 1) Misconception & Outright Not True: Boeing hid the MCAS system, its design functions, etc from anyone. Boeing clearly and fully told both all the regu...

Sun May 26, 2019 9:35 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

JT043, JT610 and ET302 proved that a new "potential failure or variation of failure" was not appropriately handled by the existing procedures and training. Existing procedures and training seemed to work for JT043. It did take someone who recognized a "Runaway Stabilizer" and ad...

Sun May 26, 2019 7:45 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

furthermore, MCAS 2.0 will turn itself off *by design* after activating once. So, after the "protection" is needed once, it will not be available again (not clear for how long). I think you're incorrect on how MCAS 2.0 will function. - MCAS 2.0 will activate once when both AoA vanes excee...

Thu May 23, 2019 11:43 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

If China will not approve the 737 MAX for domestic operation, then why will the Chinese 737 MAX completion center be operational?

Thu May 23, 2019 11:27 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

Compensation is nothing compared to Chinese never letting MAX to fly. Half of the world's population live in that area. Then I guess that the 737 MAX Chinese completion center will be shutdown. https://www.seattletimes.com/business/boeing-aerospace/boeing-set-to-deliver-first-737-jet-from-completio...

Wed May 22, 2019 7:58 pm
Forum: Civil Aviation
Topic: Boeing 777X Testing Thread - 2019
Replies: 1441
Views: 370377

### Re: Boeing 777X Testing Thread - 2019

The initial 777 roll out to first flight was a little over 2 months. From Wikipedia: "On April 9, 1994, the first 777, line number WA001, was rolled out in a series of 15 ceremonies held during the day to accommodate the 100,000 invited guests.[52] The first flight took place on June 12, 1994&...

Wed May 22, 2019 5:52 pm
Forum: Civil Aviation
Topic: Boeing 777X Testing Thread - 2019
Replies: 1441
Views: 370377

### Re: Boeing 777X Testing Thread - 2019

The initial 777 roll out to first flight was a little over 2 months. From Wikipedia: "On April 9, 1994, the first 777, line number WA001, was rolled out in a series of 15 ceremonies held during the day to accommodate the 100,000 invited guests.[52] The first flight took place on June 12, 1994&q...

Tue May 21, 2019 3:06 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

-->

PixelFlight wrote:
I still will believe both of you only when you will be able to describe in detail how is done a 737 NG/MAX runaway stabilizer training session on a simulator.

Is this the sort of thing you're looking for?

Tue May 21, 2019 2:32 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

All 4 flights with similar conditions reacted in a similar way and retracted flaps. Good Airmanship? following Unreliable Airspeed NNC? or just plain wrong because they were not you? Before we go any further with this discussion, please name the 4th flight you're referring to. I have: JT 043 JT 610...

Tue May 21, 2019 1:10 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

Flaps retracted because airspeed exceeded the max allowed for the flap setting? Do you know which is dominant and which recessive where there is a conflict between what the NNC demands and what the operating manual demands eg manual gives max speed allowed for 5, 10, 15 flaps but NNC specifies keep...

Tue May 21, 2019 1:02 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

https://www.bloomberg.com/news/articles/2019-05-21/boeing-max-could-stay-grounded-beyond-this-year-indonesia-says?srnd=premium-asia Despite what many fan boys may say, the world will put safety first. It is snarky comments and attitudes like this that have ruined this thread. What "fan boys&qu...

Tue May 21, 2019 12:59 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

So you want really insist on Boeing telling everybody about MCAS and allowing training for that new dangerous situation, would not have prevented the crashes? Really? After the EAD, the world knew about MCAS and Boeing did not prevent any airline operating the MAX from training for a Stabilizer Run...

Tue May 21, 2019 12:53 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

Lion Air Preliminary Report relating to JT043- "The PIC performed three Non-Normal Checklists and none contained the instruction “Plan to land at the nearest suitable airport”. JT043 followed your much vaunted NNCs to the letter. surely you support this? Ironically, JT043 was the one of three ...

Tue May 21, 2019 12:42 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

So. you require the crew to follow procedure with precision. Which one, since you now offer two again? Stall recovery- when there is no stall? or Runaway Stabiliser - when there is no runaway? Perhaps they should run Airspeed Unreliable, since Airspeed unreliable is present, and in climb since they...

Tue May 21, 2019 5:12 am
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

Then that claim was off topic too. The claim was being made to illustrate the efficacy of ET pilot training. As pilot training levels have been discussed extensively in this thread, it was relevant to the general topic. Maybe we can stop discussing pilots because it is off topic in this thread? The...

Tue May 21, 2019 5:01 am
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

It might sound like that, but maybe you have forgotten that the stick shaker was active immediately following take-off. Looking out of the window whilst so close to the runway would give you some idea of your progress. Whereas when flying along at 4,000' AGL or higher, I agree you will have fewer c...

Tue May 21, 2019 4:14 am
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

You are making blind assumptions, both those pilots had in total 10k hours of flying time between them (over a year in the air). What experience do you have ? About 90K hours of Part 25 airplane design & performance, safety and certification experience. While I agree that Boeing had a major rol...

Tue May 21, 2019 3:39 am
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

But is it accepted practice of 737 pilots, to disregard a stick shaker if occurring only on one side, especially if there are other issues with the aircraft? Perhaps a stick shaker on one side in the NG and MAX is more common than it should be, so pilots have learned to ignore or work around. Do yo...

Tue May 21, 2019 1:53 am
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

Stick shaker once side only. There it is. Follow "Runaway Stabilizer NNC". Strictly only applicable if there is uncommanded stabilizer activity. However, if the "Runaway Stabilizer" NNC had been performed correctly at Flaps 5, the ET 302 crash would not have happened. Nothing ab...

Tue May 21, 2019 1:33 am
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

How about naming MCAS and explaining exactly what it does. Wouldn't have prevented the ET 302 crash. Complying with the EAD and properly executing the "Runaway Stabilizer" NNC would have avoided the crash. How about explaining that AoA disagree does not work, even so it is not optional an...

Tue May 21, 2019 12:16 am
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

The Boeing EAD didn't think so. The FAA EAD is written for erroneous MCAS operation. If Flaps are down, no erroneous MCAS operation so run the "STALL RECOVERY" NNC that the stick shaker is prompting you do do. Yet Boeing knew that. Transparency. Openness. It goes a long way and could have...

Mon May 20, 2019 11:36 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

ET302 _DID_NOT_STALL_ !!!!! How hard is that to understand, really ? :banghead: There no point to do a NCC that do not correspond to the situation. I understand perfectly well that ET 302 did not stall. But the sticker shaker was active through out the ET 302 flight. With an active stick shaker, wh...

Mon May 20, 2019 11:29 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

The point is: Why were the Flaps retracted with an active stick shaker, contrary to the "STALL RECOVERY" NNC ? Because they looked out of the window and could see they were clearly not in a stall situation? How does looking out the window tell you that you aren't near stall? That sounds l...

Mon May 20, 2019 11:15 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

ET302 _DID_NOT_STALL_ !!!!! How hard is that to understand, really ? :banghead: There no point to do a NCC that do not correspond to the situation. I understand perfectly well that ET 302 did not stall. But the sticker shaker was active through out the ET 302 flight. With an active stick shaker, wh...

Mon May 20, 2019 10:49 pm
Forum: Civil Aviation
Topic: Boeing 737MAX Grounded Worldwide Q2 2019
Replies: 3768
Views: 412260

### Re: Boeing 737MAX Grounded Worldwide Q2 2019

Since you happily brought up AA and DL in your post about safety records, I did go on to point out later that the american carriers you happily point to as vaunted examples of safe ops have experienced their share of dangerous excusions and hard landing write offs the last decade. Not to mention th...

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