User avatar
PixelFlight
Posts: 638
Joined: Thu Nov 08, 2018 11:09 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Thu Sep 05, 2019 10:05 pm

sgrow787 wrote:
PixelFlight wrote:
sgrow787 wrote:
Three ways to cutoff MCAS 1.0:
(1) Extend flaps
(2) Go to autopilot
(3) Flip both aisle Cutout switches

Only (3) applies to high speed maneuver.

But Im not a pilot. (getting tired of having to say that)

5 ways to cutoff MCAS 2.0:
(1)(2)(3) same for v1.0
(4) Duck tape the left AOA to +75 deg before takeoff
(5) Install a modified build into the left FCC that mimics a recurring bitflip on the MCAS Engaged flag. Then takeoff.

:scratchchin: :mischievous:
(3) or any of the cutout switches (there are connected in serial).
(4) or the right AoA (any too high differences disable MCAS).
(6) Move the yoke in the opposite pitch (MCAS V2 grant elevator authority).


Your (6) will only work on a NG... the column cutout is disengaged on the Max when MCAS Engaged is TRUE. Also the idea is misfunction rather than pilot error. Ie something that happens beyond the pilots control.

Right/leftness is immaterial.

The NG don't have MCAS anyway...
You are right that the column cutout is disengaged for MCAS trim stabilizer activation, but the stabilizer trim column cutout have nothing to do with the elevator. According to the MCAS fix list, the elevator authority is implemented directly into the MCAS V2, so MCAS will stop moving the stabilizer before compromising the elevator authority. It's a bit tricky, but it effectively disable MCAS at some point.
Last edited by PixelFlight on Thu Sep 05, 2019 10:08 pm, edited 1 time in total.
 
sgrow787
Posts: 262
Joined: Fri May 16, 2014 8:12 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Thu Sep 05, 2019 10:06 pm

chicawgo wrote:
zkojq wrote:
planecane wrote:

I respect your opinion and your post has definitely been a wakeup call as far as expectations of who is sitting at the controls. I guess I had hoped that at least one of the two pilots would be above average in skill and quick thinking/problem solving ability.

Mate if you don't want people to accuse you of being a troll, you really shouldn't go making statements like that.


You don't have to agree with them but that's not a "troll" statement. It's a valid argument. I think most average non-a.net passengers expect that commercial pilots in charge of 150+ lives are highly trained and at least above average in problem solving issues you'd find on...ummm... a plane. If this whole disaster showed that we can't expect that from many pilots, that is a valid issue to address. Why is that trolling?


Because the... stuff in this Max saga ... the majority of this "shtuff" is about how a plane manufacturer certified a plane that wasnt ready to be certified. Because the dead pilots arent here to defend themselves. And because the troll himself stated lets wait for the NTSB report before coming to conclusions.
Just one sensor,
Oh just one se-en-sor,
Just one sensor,
Ooh ooh oo-ooh
Oo-oo-ooh.
 
sgrow787
Posts: 262
Joined: Fri May 16, 2014 8:12 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Thu Sep 05, 2019 10:14 pm

PixelFlight wrote:
The NG don't have MCAS anyway...


But there is STS that can runaway apparently, on the NG.

You are right that the column cutout is disengaged for MCAS trim stabilizer activation, but the stabilizer trim column cutout have nothing to do with the elevator. According to the MCAS fix list, the elevator authority is implemented directly into the MCAS V2, so MCAS will stop moving the stabilizer before compromising the elevator authority. It's a bit tricky, but it effectively disable MCAS at some point.


Its hard to engage with you Pixel because your grammer is too ambiguous. Just being honest.

I think the answer is, for a useful flight test, they want MCAS completely off for the test. Not off based on column force value/direction.
Just one sensor,
Oh just one se-en-sor,
Just one sensor,
Ooh ooh oo-ooh
Oo-oo-ooh.
 
User avatar
PixelFlight
Posts: 638
Joined: Thu Nov 08, 2018 11:09 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Thu Sep 05, 2019 11:39 pm

sgrow787 wrote:
PixelFlight wrote:
The NG don't have MCAS anyway...


But there is STS that can runaway apparently, on the NG.

You are right that the column cutout is disengaged for MCAS trim stabilizer activation, but the stabilizer trim column cutout have nothing to do with the elevator. According to the MCAS fix list, the elevator authority is implemented directly into the MCAS V2, so MCAS will stop moving the stabilizer before compromising the elevator authority. It's a bit tricky, but it effectively disable MCAS at some point.


Its hard to engage with you Pixel because your grammer is too ambiguous. Just being honest.

I think the answer is, for a useful flight test, they want MCAS completely off for the test. Not off based on column force value/direction.

Sorry for my English, not my native tongue. Try my best... :guilty:
The MCAS V2 fix list contain this entry "To limit how much MCAS can move the horizontal stab to guarantee sufficient handling capability using elevator alone." http://www.b737.org.uk/mcas.htm#fix
My conclusion is that using the elevator should be enough to cancel the MCAS activation of the stabilizer trim.
 
sgrow787
Posts: 262
Joined: Fri May 16, 2014 8:12 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 12:03 am

PixelFlight wrote:
Sorry for my English, not my native tongue. Try my best... :guilty:
The MCAS V2 fix list contain this entry "To limit how much MCAS can move the horizontal stab to guarantee sufficient handling capability using elevator alone." http://www.b737.org.uk/mcas.htm#fix
My conclusion is that using the elevator should be enough to cancel the MCAS activation of the stabilizer trim.


And my response still applies (minus the harshness, sorry).

The purpose of a high speed wind up to stall flight test, without MCAS, is to determine the worst case survivability of the a/c, which is based on its intrinsic aerodynamic stability.
Just one sensor,
Oh just one se-en-sor,
Just one sensor,
Ooh ooh oo-ooh
Oo-oo-ooh.
 
User avatar
lightsaber
Moderator
Posts: 18109
Joined: Wed Jan 19, 2005 10:55 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 1:15 am

Revelation wrote:
Olddog wrote:
freakyrat wrote:
From This mornings Dallas Morning News.
Southwest is optimistic.

https://www.dallasnews.com/business/loc ... nksgiving/


SW has showed multiple times they are not the best informed....

It's not just WN that has optimistic things to say.

WN:

"We're assuming that we will have the go-ahead to return the Max to service by, call it the beginning to mid-November," Southwest Chief Financial Officer Tammy Romo said Wednesday at a Cowen & Co. transportation conference in Boston.

UA:

"We've told them that from our perspective, nothing prevents us from physically taking as many aircraft as they can deliver to us," (Gerry Laderman, the airline's finance chief) said at the conference. "They're going to be the constraint on that."


AS:
"We're confident in the Max," said CFO Brandon Pedersen. "It's going to be a great airplane for us."

I would take the word of SouthWest, who is probably the most informed MAX customer, over other discussion. I'm not saying the plane will hit target. I'm saying everyone trying to dispute the MAX will fly again will eventually be proven wrong.

But I notice in those links airlines are demanding 60 day notice, minimum, before restarting service (to market and sell tickets).

Lightsaber
IM messages to mods on warnings and bans will be ignored and nasty ones will result in a ban.
 
art
Posts: 2931
Joined: Tue Feb 08, 2005 11:46 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 1:25 am

WIederling wrote:
FAA has been instantiated with two jobs:

* certify and overlook all things air transport.
* further US aero space interests.

this is a clash afaics.


I wpuld say absurd.
 
747megatop
Posts: 1712
Joined: Wed May 23, 2007 8:22 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 1:39 am

chicawgo wrote:
zkojq wrote:
planecane wrote:

I respect your opinion and your post has definitely been a wakeup call as far as expectations of who is sitting at the controls. I guess I had hoped that at least one of the two pilots would be above average in skill and quick thinking/problem solving ability.

Mate if you don't want people to accuse you of being a troll, you really shouldn't go making statements like that.


You don't have to agree with them but that's not a "troll" statement. It's a valid argument. I think most average non-a.net passengers expect that commercial pilots in charge of 150+ lives are highly trained and at least above average in problem solving issues you'd find on...ummm... a plane. If this whole disaster showed that we can't expect that from many pilots, that is a valid issue to address. Why is that trolling?

I think that expectation (pilots are highly trained etc. etc.) is not just from the average non-a.net passengers but from within the aviation industry itself. I would be shocked if that isn't the case. A commercial jet is not a car where a 16 year old can get behind the wheel after passing a DMV test after going to a driving school for 20 hours and would just slam the door and walk off if the car doesn't start of malfunctions.
 
freakyrat
Posts: 1738
Joined: Fri Aug 22, 2008 1:04 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 2:18 am

747megatop wrote:
chicawgo wrote:
zkojq wrote:
Mate if you don't want people to accuse you of being a troll, you really shouldn't go making statements like that.


You don't have to agree with them but that's not a "troll" statement. It's a valid argument. I think most average non-a.net passengers expect that commercial pilots in charge of 150+ lives are highly trained and at least above average in problem solving issues you'd find on...ummm... a plane. If this whole disaster showed that we can't expect that from many pilots, that is a valid issue to address. Why is that trolling?

I think that expectation (pilots are highly trained etc. etc.) is not just from the average non-a.net passengers but from within the aviation industry itself. I would be shocked if that isn't the case. A commercial jet is not a car where a 16 year old can get behind the wheel after passing a DMV test after going to a driving school for 20 hours and would just slam the door and walk off if the car doesn't start of malfunctions.


Yes the pilots are highly trained but even though these aircraft are complex Airbus has automated the A320 so much that an average commercial pilot with minimum hours can get in the Sim and figure it out. I've even seen a 15yr old get in one of the FDS A320 Sims with an instructor of course as a gift for his birthday and have fun with it. It's all well in good when everything is going right but As you said A highly trained and experienced pilot is hard to beat.
 
freakyrat
Posts: 1738
Joined: Fri Aug 22, 2008 1:04 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 2:21 am

Of any of the US pilots that fly the MAX, Southwest pilots have the most experience with the aircraft conducting over 34,000 safe flights with the aircraft. Personally I woudn't hesitate getting on board this aircraft when it returns to service. It has a lot of climb power and is a quiet and comfortable ride.
 
sgrow787
Posts: 262
Joined: Fri May 16, 2014 8:12 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 2:51 am

kayik wrote:
United says it will allow passengers to avoid 737 Max flights

https://edition.cnn.com/2019/09/04/busi ... index.html


I wouldnt say thats "letting passengers avoid" the Max. Rebooking for free on the next soonest available 737 NG will likely be a significant delay, and unplanned for, which will force some passengers to board the Max just to get to their destination. What United needs to do is allow customers to see the plane type during booking. And of course remove the clause in the fine print that says they can substitute another aircraft at will.
Just one sensor,
Oh just one se-en-sor,
Just one sensor,
Ooh ooh oo-ooh
Oo-oo-ooh.
 
IADFCO
Posts: 128
Joined: Sun May 22, 2016 4:20 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 4:31 am

Just a reminder that, according to Boeing, MCAS 2.0 will activate only once when the angle of attack crosses (i.e. becomes higher) than the activation threshold, and will stay inactive until the angle of attack becomes smaller than the threshold. So, let's say that the activation threshold is 12 degrees (I don't know what the real value is). If you are in a turn, e.g., because of an avoidance maneuver, and go to 13 degrees, MCAS will activate. You fight it for 10 seconds (now you will have enough control authority, says Boeing), and then MCAS will stop its action until you go back to below 12 degrees. If you stay at 13 degrees after the 10 seconds, you lose all the benefits (protections?) of MCAS, whatever they are. This with MCAS functioning as designed, with no failures of any kind.

If I were a certification agency, I would want to test the behavior of the aircraft in these precise conditions, whether or not they are covered by existing regulations, and I filed a comment with the FAA to this effect during the official commenting period. Regulations are a means to an end, the end is safety.

I brought this up a million posts ago, and I got all sort of grief from the pro-Boeing crowd. I am not looking forward to relitigate the issue, but I hope we can all agree that it can be sorted out, one way or another, with less than a morning worth of flight tests. I hope that the FAA performs those tests, and if not, that the EASA does.
 
User avatar
seahawk
Posts: 8704
Joined: Fri May 27, 2005 1:29 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 4:59 am

The FAA will test all this and the MAX will be the safest plane it its class when it returns to service early October.
 
amtravels
Posts: 9
Joined: Wed Jun 19, 2019 12:54 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 5:18 am

sgrow787 wrote:
kayik wrote:
United says it will allow passengers to avoid 737 Max flights

https://edition.cnn.com/2019/09/04/busi ... index.html


I wouldnt say thats "letting passengers avoid" the Max. Rebooking for free on the next soonest available 737 NG will likely be a significant delay, and unplanned for, which will force some passengers to board the Max just to get to their destination. What United needs to do is allow customers to see the plane type during booking. And of course remove the clause in the fine print that says they can substitute another aircraft at will.


Did you even read the article? Andrew Nocella says they are going to tell customers what plane they’ll be flying when booking. Additionally, equipment info is available at the gate either from the agent or on the monitors.
 
sgrow787
Posts: 262
Joined: Fri May 16, 2014 8:12 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 5:26 am

amtravels wrote:
sgrow787 wrote:
kayik wrote:
United says it will allow passengers to avoid 737 Max flights

https://edition.cnn.com/2019/09/04/busi ... index.html


I wouldnt say thats "letting passengers avoid" the Max. Rebooking for free on the next soonest available 737 NG will likely be a significant delay, and unplanned for, which will force some passengers to board the Max just to get to their destination. What United needs to do is allow customers to see the plane type during booking. And of course remove the clause in the fine print that says they can substitute another aircraft at will.


Did you even read the article? Andrew Nocella says they are going to tell customers what plane they’ll be flying when booking. Additionally, equipment info is available at the gate either from the agent or on the monitors.


Nope. It says, at the time of booking, what planes they "expect to use", and then says planes change sometimes. And youll find out when you get to the gate. Thats too late for comfort in my book.

I'll get on one after Muillenburg completes 6 months of commuting between Chicago and Seattle. Thats 3 round trips a week.
Just one sensor,
Oh just one se-en-sor,
Just one sensor,
Ooh ooh oo-ooh
Oo-oo-ooh.
 
WIederling
Posts: 8888
Joined: Sun Sep 13, 2015 2:15 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 7:27 am

art wrote:
WIederling wrote:
FAA has been instantiated with two jobs:

* certify and overlook all things air transport.
* further US aero space interests.

this is a clash afaics.


I wpuld say absurd.

Would you elaborate?

There is enough indication that the FAA takes a partisan approach to certification.
Good sample case is described in the "A380" book. Lots of similar "table tilting" activity visible.
If you go about and (have to) boost your local stuff beyond reason things like the MAX crashes happen.
Murphy is an optimist
 
User avatar
Dutchy
Posts: 9982
Joined: Sat Nov 03, 2007 1:25 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 7:31 am

IADFCO wrote:
Just a reminder that, according to Boeing, MCAS 2.0 will activate only once when the angle of attack crosses (i.e. becomes higher) than the activation threshold, and will stay inactive until the angle of attack becomes smaller than the threshold. So, let's say that the activation threshold is 12 degrees (I don't know what the real value is). If you are in a turn, e.g., because of an avoidance maneuver, and go to 13 degrees, MCAS will activate. You fight it for 10 seconds (now you will have enough control authority, says Boeing), and then MCAS will stop its action until you go back to below 12 degrees. If you stay at 13 degrees after the 10 seconds, you lose all the benefits (protections?) of MCAS, whatever they are. This with MCAS functioning as designed, with no failures of any kind.

If I were a certification agency, I would want to test the behavior of the aircraft in these precise conditions, whether or not they are covered by existing regulations, and I filed a comment with the FAA to this effect during the official commenting period. Regulations are a means to an end, the end is safety.

I brought this up a million posts ago, and I got all sort of grief from the pro-Boeing crowd. I am not looking forward to relitigate the issue, but I hope we can all agree that it can be sorted out, one way or another, with less than a morning worth of flight tests. I hope that the FAA performs those tests, and if not, that the EASA does.


Wasn't the problem in those two instances that there was an improper reading of the angle of attack sensor. How will they handle tha? Perhaps this has come up a zillion post ago, but it is a bit too much to read it all, so I lost track, sorry for that.
Many happy landings, greetings from The Netherlands!
 
sgrow787
Posts: 262
Joined: Fri May 16, 2014 8:12 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 7:57 am

Dutchy wrote:
IADFCO wrote:
Just a reminder that, according to Boeing, MCAS 2.0 will activate only once when the angle of attack crosses (i.e. becomes higher) than the activation threshold, and will stay inactive until the angle of attack becomes smaller than the threshold. So, let's say that the activation threshold is 12 degrees (I don't know what the real value is). If you are in a turn, e.g., because of an avoidance maneuver, and go to 13 degrees, MCAS will activate. You fight it for 10 seconds (now you will have enough control authority, says Boeing), and then MCAS will stop its action until you go back to below 12 degrees. If you stay at 13 degrees after the 10 seconds, you lose all the benefits (protections?) of MCAS, whatever they are. This with MCAS functioning as designed, with no failures of any kind.

If I were a certification agency, I would want to test the behavior of the aircraft in these precise conditions, whether or not they are covered by existing regulations, and I filed a comment with the FAA to this effect during the official commenting period. Regulations are a means to an end, the end is safety.

I brought this up a million posts ago, and I got all sort of grief from the pro-Boeing crowd. I am not looking forward to relitigate the issue, but I hope we can all agree that it can be sorted out, one way or another, with less than a morning worth of flight tests. I hope that the FAA performs those tests, and if not, that the EASA does.


Wasn't the problem in those two instances that there was an improper reading of the angle of attack sensor. How will they handle tha? Perhaps this has come up a zillion post ago, but it is a bit too much to read it all, so I lost track, sorry for that.


Most of us here are exhausted with the saga. My suggestion is to google "Seattle Times 737 Max" and start from the Ethiopian crash in March.
Just one sensor,
Oh just one se-en-sor,
Just one sensor,
Ooh ooh oo-ooh
Oo-oo-ooh.
 
XRAYretired
Posts: 623
Joined: Fri Mar 15, 2019 11:21 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 8:48 am

Dutchy wrote:
IADFCO wrote:
Just a reminder that, according to Boeing, MCAS 2.0 will activate only once when the angle of attack crosses (i.e. becomes higher) than the activation threshold, and will stay inactive until the angle of attack becomes smaller than the threshold. So, let's say that the activation threshold is 12 degrees (I don't know what the real value is). If you are in a turn, e.g., because of an avoidance maneuver, and go to 13 degrees, MCAS will activate. You fight it for 10 seconds (now you will have enough control authority, says Boeing), and then MCAS will stop its action until you go back to below 12 degrees. If you stay at 13 degrees after the 10 seconds, you lose all the benefits (protections?) of MCAS, whatever they are. This with MCAS functioning as designed, with no failures of any kind.

If I were a certification agency, I would want to test the behavior of the aircraft in these precise conditions, whether or not they are covered by existing regulations, and I filed a comment with the FAA to this effect during the official commenting period. Regulations are a means to an end, the end is safety.

I brought this up a million posts ago, and I got all sort of grief from the pro-Boeing crowd. I am not looking forward to relitigate the issue, but I hope we can all agree that it can be sorted out, one way or another, with less than a morning worth of flight tests. I hope that the FAA performs those tests, and if not, that the EASA does.


Wasn't the problem in those two instances that there was an improper reading of the angle of attack sensor. How will they handle tha? Perhaps this has come up a zillion post ago, but it is a bit too much to read it all, so I lost track, sorry for that.

A good summary of everything MCAS. Put it in your back pocket and you can ignore a lot of the uninformed guesswork going on as well. (I'm not including IADFCO post above in that, by the way).
www.b737.org.uk/mcas.htm

Ray
 
User avatar
PixelFlight
Posts: 638
Joined: Thu Nov 08, 2018 11:09 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 8:54 am

IADFCO wrote:
Just a reminder that, according to Boeing, MCAS 2.0 will activate only once when the angle of attack crosses (i.e. becomes higher) than the activation threshold, and will stay inactive until the angle of attack becomes smaller than the threshold. So, let's say that the activation threshold is 12 degrees (I don't know what the real value is). If you are in a turn, e.g., because of an avoidance maneuver, and go to 13 degrees, MCAS will activate. You fight it for 10 seconds (now you will have enough control authority, says Boeing), and then MCAS will stop its action until you go back to below 12 degrees. If you stay at 13 degrees after the 10 seconds, you lose all the benefits (protections?) of MCAS, whatever they are. This with MCAS functioning as designed, with no failures of any kind.

If I were a certification agency, I would want to test the behavior of the aircraft in these precise conditions, whether or not they are covered by existing regulations, and I filed a comment with the FAA to this effect during the official commenting period. Regulations are a means to an end, the end is safety.

I brought this up a million posts ago, and I got all sort of grief from the pro-Boeing crowd. I am not looking forward to relitigate the issue, but I hope we can all agree that it can be sorted out, one way or another, with less than a morning worth of flight tests. I hope that the FAA performs those tests, and if not, that the EASA does.

Fully agree. What you describes, with the addition of all the ways MCAS can be disabled, pretty well illustrate that the discrete command design is pushed too far into the complexity. It's time to give up and take the full authority fly by wire design that handle maneuver characteristics and protection in a far much simple, reliable, and smooth way.
 
Noshow
Posts: 1008
Joined: Wed Jun 15, 2016 3:20 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 8:54 am

We still don‘t know how a raw MAX is flying without MCAS being active. If it is just a legally required stick feel feature as claimed it should be possible to fly without it?
 
KFLLCFII
Posts: 3494
Joined: Sat Sep 11, 2004 7:08 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 10:14 am

kayik wrote:
United says it will allow passengers to avoid 737 Max flights

https://edition.cnn.com/2019/09/04/busi ... index.html


They will publicly do this until they silently remove the option. (What about last-minute gate substitutions when the only available plane is a MAX?)

It may be best to avoid certain airlines altogether after the initial re-entry into service.
"About the only way to look at it, just a pity you are not POTUS KFLLCFII, seems as if we would all be better off."
 
uta999
Posts: 739
Joined: Mon Jun 14, 2010 11:10 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 10:42 am

The fact that it has taken Boeing nearly a year, since the first accident to come up with an MCAS that may or may not work, or satisfy authorities both in the US and abroad, leads me to believe that it cannot be done. I don't think an aircraft of this era, already being very old tech can survive a grounding lasting more than a year. Talk of lifting the grounding of the MAX is still very premature. If it does happen, it is purely to save the company. Not because it is safe.
Your computer just got better
 
planecane
Posts: 1136
Joined: Thu Feb 09, 2017 4:58 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 10:47 am

sgrow787 wrote:
PixelFlight wrote:
sgrow787 wrote:
Three ways to cutoff MCAS 1.0:
(1) Extend flaps
(2) Go to autopilot
(3) Flip both aisle Cutout switches

Only (3) applies to high speed maneuver.

But Im not a pilot. (getting tired of having to say that)

5 ways to cutoff MCAS 2.0:
(1)(2)(3) same for v1.0
(4) Duck tape the left AOA to +75 deg before takeoff
(5) Install a modified build into the left FCC that mimics a recurring bitflip on the MCAS Engaged flag. Then takeoff.

:scratchchin: :mischievous:
(3) or any of the cutout switches (there are connected in serial).
(4) or the right AoA (any too high differences disable MCAS).
(6) Move the yoke in the opposite pitch (MCAS V2 grant elevator authority).


Your (6) will only work on a NG... the column cutout is disengaged on the Max when MCAS Engaged is TRUE. Also the idea is misfunction rather than pilot error. Ie something that happens beyond the pilots control (granted, I included AP, flaps, and cutout switches.... long day..)

Right/leftness is immaterial.

Actually, maybe you can clarify on (6), since Im lost on the elevator thing.


With MCAS 2.0, trimming opposite MCAS also will disengage it IIRC.
 
mjoelnir
Posts: 8499
Joined: Sun Feb 03, 2013 11:06 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 10:48 am

IMO one should think about how manual electrical trim is done in a 737NG or MAX before the now advertised changes are done.

The inputs from the switches are not to the trim motor relay, but into a computer. As I understand it, the cut out switches are also no direct power off switches, but again input into a computer. That all on the basis of only one computer operating without any redundancy. If this computer freezes or bits are flipped the inputs of the pilots get no response. Than you are left with manual trim and that is not possible to use over all the flight envelope.

My question would be, how did this situation got ever certified?

Now the redundancy is supposed to be supplied by two computers operating in parallel. Still worlds away from the common triple redundancy common for aviation and space applications.

Now we have some Boeing fans here screaming politics, when EASA puts some hard questions to the FAA and the self certifying Boeing.

EASA is just doing their due diligence, something they should have done long ago instead of trusting the FAA certifications.

I just hope that EASA will push their view and hopefully we will see a save 737MAX in the future.
 
FluidFlow
Posts: 290
Joined: Wed Apr 10, 2019 6:39 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 11:10 am

uta999 wrote:
The fact that it has taken Boeing nearly a year, since the first accident to come up with an MCAS that may or may not work, or satisfy authorities both in the US and abroad, leads me to believe that it cannot be done. I don't think an aircraft of this era, already being very old tech can survive a grounding lasting more than a year. Talk of lifting the grounding of the MAX is still very premature. If it does happen, it is purely to save the company. Not because it is safe.


The aircraft will be safe enough, statistically it will probably be never as safe as the NG, but it will be safe enough, no matter what the different authorities say. Boeing just cannot afford another crash related to bad design if they want to stay in the NB market.

The real problem stems from the fact that the FAA and Boeing worked too close together and how the situation was handled after the Lion Air crash.

If Boeing would have then stated, that the aircraft has to be grounded because Boeing changed MCAS without informing the FAA and also failed to do a proper risk analysis based on measured quantities instead of unproven assumptions the whole thing would have been trough and back in the air after 3 months.

The FAA would have kept face and re-certification would have been a no brainer. Unfortunately this did not happen and Boeing tried to hide the whole thing and hoped for the best.

The only good thing from this is, that a) Boeing needs to get this right and knows full well that if they don't it is game over, therefore the fix will be good and b) the FAA will never ever be allowed to let something like this slip if they want to have any authority left in the aviation industry. Both of them are one step away from becoming the biggest "Icarus" of aviation.
 
User avatar
Polot
Posts: 9473
Joined: Thu Jul 28, 2011 3:01 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 11:15 am

FluidFlow wrote:
uta999 wrote:
The fact that it has taken Boeing nearly a year, since the first accident to come up with an MCAS that may or may not work, or satisfy authorities both in the US and abroad, leads me to believe that it cannot be done. I don't think an aircraft of this era, already being very old tech can survive a grounding lasting more than a year. Talk of lifting the grounding of the MAX is still very premature. If it does happen, it is purely to save the company. Not because it is safe.


The aircraft will be safe enough, statistically it will probably be never as safe as the NG, but it will be safe enough, no matter what the different authorities say. Boeing just cannot afford another crash related to bad design if they want to stay in the NB market.


Let’s be honest- it will be never be safe enough for some members here who just want to complain and bash Boeing as much as possible. If Boeing takes a year to fix it that obviously means they don’t know what to do or how to fix it and something is just being approved to save the company. Meanwhile if Boeing fixed it in 2 months those exact same members would be complaining how Boeing just rushed a fixed and it was approved to prevent a delayed grounding and obviously it is just a bandaid solution and the plane is not fixed and still a danger.

In this thread you just need to look for the post that are constructive (like mjoelnr’s, who I know is not the biggest Boeing fan) and ignore those that are not.
 
User avatar
PixelFlight
Posts: 638
Joined: Thu Nov 08, 2018 11:09 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 11:32 am

mjoelnir wrote:
IMO one should think about how manual electrical trim is done in a 737NG or MAX before the now advertised changes are done.

The inputs from the switches are not to the trim motor relay, but into a computer. As I understand it, the cut out switches are also no direct power off switches, but again input into a computer. That all on the basis of only one computer operating without any redundancy. If this computer freezes or bits are flipped the inputs of the pilots get no response. Than you are left with manual trim and that is not possible to use over all the flight envelope.

1) The trim switches on the yokes don't go into a computer, but pass through some relays to end directly into the trim motor controller.
2) The trim cutoff switches are connected in serial between a +28V power supply and the electromagnet of the triple phase relay that directly power the trim motor. There is a probe signal for the FCCs computer, but the main function did not involve any computer.
3) I don't know how the stab trim controller is designed. While it could technically contain a micro-controller, I don't think this is the case when it was designed precisely to avoid computer related safety risk. Most probably the stab trim controllers (there are two of them) are implemented with a bunch of analog and discrete logic gate. I don't see the need of any bit of memory into the stab trim controller. If someone have more design information about the stab trim controllers, please share.
 
hooverman
Posts: 279
Joined: Tue Oct 25, 2011 9:20 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 11:54 am

seahawk wrote:
The FAA will test all this and the MAX will be the safest plane it its class when it returns to service early October.


October? What airline? Worldwide?
 
gregpodpl
Posts: 54
Joined: Fri Jan 04, 2013 3:49 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 12:10 pm

seahawk wrote:
The FAA will test all this and the MAX will be the safest plane it its class when it returns to service early October.

Is the class "planes that killed 300 people in last year" ?
 
User avatar
Revelation
Posts: 21368
Joined: Wed Feb 09, 2005 9:37 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 12:27 pm

uta999 wrote:
The fact that it has taken Boeing nearly a year, since the first accident to come up with an MCAS that may or may not work, or satisfy authorities both in the US and abroad, leads me to believe that it cannot be done..

We just had several posts on EASA's four conditions for RTS that should make it clear that EASA is not interested in just a MCAS fix.

In turn your time line for world wide RTS is problematic.

EASA is within its rights to ask for the things it has asked for, but resolving them will take time.

Some of the things it asks for, such as closure on both JT and ET accidents, presumably will not come in your one year time frame.

Even if Boeing has the data to clearly determine root cause, it cannot release it to anyone till Indonesia and Ethiopia accident investigators allow it.

Rock, meet hard place.
Wake up to find out that you are the eyes of the world
The heart has its beaches, its homeland and thoughts of its own
Wake now, discover that you are the song that the morning brings
The heart has its seasons, its evenings and songs of its own
 
Elementalism
Posts: 463
Joined: Sat Jun 10, 2017 4:03 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 12:59 pm

KFLLCFII wrote:
kayik wrote:
United says it will allow passengers to avoid 737 Max flights

https://edition.cnn.com/2019/09/04/busi ... index.html


They will publicly do this until they silently remove the option. (What about last-minute gate substitutions when the only available plane is a MAX?)

It may be best to avoid certain airlines altogether after the initial re-entry into service.


They will do this until their data analytics says nobody cares.
 
JonesNL
Posts: 41
Joined: Tue Aug 06, 2019 2:40 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 1:06 pm

Revelation wrote:
uta999 wrote:
The fact that it has taken Boeing nearly a year, since the first accident to come up with an MCAS that may or may not work, or satisfy authorities both in the US and abroad, leads me to believe that it cannot be done..

We just had several posts on EASA's four conditions for RTS that should make it clear that EASA is not interested in just a MCAS fix.

In turn your time line for world wide RTS is problematic.

EASA is within its rights to ask for the things it has asked for, but resolving them will take time.

Some of the things it asks for, such as closure on both JT and ET accidents, presumably will not come in your one year time frame.

Even if Boeing has the data to clearly determine root cause, it cannot release it to anyone till Indonesia and Ethiopia accident investigators allow it.

Rock, meet hard place.


I really hope the EASA isn't going to wait for the closure of the ET accident. That would mean that an RTS for the high season of summer 2020 is not feasible. If they do the financial impact on Boeing would be crushing; rock, meet daimond.
 
User avatar
Revelation
Posts: 21368
Joined: Wed Feb 09, 2005 9:37 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 1:43 pm

JonesNL wrote:
I really hope the EASA isn't going to wait for the closure of the ET accident. That would mean that an RTS for the high season of summer 2020 is not feasible. If they do the financial impact on Boeing would be crushing; rock, meet daimond.

Interesting point.

To me it suggests that there is an imperative to find a compromise.

The "April Fools" letter says:

Letter sent to the FAA on April 01, 2019.

4 conditions:

1. Design changes proposed by Boeing are EASA approved (no delegation to FAA)
2. Additional and broader independent design review has been satisfactorily completed by EASA
3. Accidents of JT610 and ET302 are deemed sufficiently understood
4. B737 MAX flight crews have been adequately trained

Seems there is some room for negotiation, but it's hard to say exactly who is deeming what sufficient understanding is, and how that party can get that understanding without being allowed full access to the accident investigation data before it is public, and how can anyone else decide the deeming is sufficient without having public access to the accident reports?

EASA sure has put itself into the role of king maker, at the risk of becoming another untrusted party should their deeming prove to not be sufficient.
Wake up to find out that you are the eyes of the world
The heart has its beaches, its homeland and thoughts of its own
Wake now, discover that you are the song that the morning brings
The heart has its seasons, its evenings and songs of its own
 
asdf
Posts: 435
Joined: Tue Mar 18, 2014 12:03 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 1:44 pm

Dutchy wrote:
Wasn't the problem in those two instances that there was an improper reading of the angle of attack sensor. How will they handle tha? Perhaps this has come up a zillion post ago, but it is a bit too much to read it all, so I lost track, sorry for that.


they compare the readings
if there is improper data the pilots will get an message

there is no more augmentation from that point

the pilots will be the redundance to fly the planes in a otherwise not certifiable state and probably "land at nearest suitable airport"
 
User avatar
aerolimani
Posts: 1200
Joined: Tue Jun 18, 2013 5:46 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 2:09 pm

Revelation wrote:
EASA sure has put itself into the role of king maker, at the risk of becoming another untrusted party should their deeming prove to not be sufficient.

I think the risk is a bit lower for the EASA than for the FAA.
1) They don't suffer the same lack of separation as between Boeing and the FAA, however real or perceived that may be.
2) They lack the potential conflict of interest as the FAA with its mission of "encouraging and developing civil aeronautics, including new aviation technology."
3) The situation has changed from the initial MAX certification. At that time, Boeing's prime imperative was to get the plane to market as quickly as possible. I'm sure Boeing recognizes that there simply cannot be any more screwups.

For the above reasons, should something go wrong, I think the EASA could sufficiently direct blame towards Boeing. I don't think they'd get away without any mud on their face, but I don't think they'd be branded as "another untrusted party."
 
FluidFlow
Posts: 290
Joined: Wed Apr 10, 2019 6:39 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 2:13 pm

aerolimani wrote:
Revelation wrote:
EASA sure has put itself into the role of king maker, at the risk of becoming another untrusted party should their deeming prove to not be sufficient.

I think the risk is a bit lower for the EASA than for the FAA.
1) They don't suffer the same lack of separation as between Boeing and the FAA, however real or perceived that may be.
2) They lack the potential conflict of interest as the FAA with its mission of "encouraging and developing civil aeronautics, including new aviation technology."
3) The situation has changed from the initial MAX certification. At that time, Boeing's prime imperative was to get the plane to market as quickly as possible. I'm sure Boeing recognizes that there simply cannot be any more screwups.

For the above reasons, should something go wrong, I think the EASA could sufficiently direct blame towards Boeing. I don't think they'd get away without any mud on their face, but I don't think they'd be branded as "another untrusted party."


If the EASA missed something then the FAA did aswell. In my eyes the only thing that could backfire on EASA is if they just drag out the process without any reason to do so. That would mean if the 4 questions are answered but there is still no RTS just because.

So I do not think the EASA would be untrusted in aircraft safety standarts but be seen as a political institution siding with Airbus and that would hurt EASA and Airbus.
 
2175301
Posts: 1505
Joined: Wed May 16, 2007 11:19 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 2:27 pm

Revelation wrote:
JonesNL wrote:
I really hope the EASA isn't going to wait for the closure of the ET accident. That would mean that an RTS for the high season of summer 2020 is not feasible. If they do the financial impact on Boeing would be crushing; rock, meet daimond.

Interesting point.

To me it suggests that there is an imperative to find a compromise.

The "April Fools" letter says:

Letter sent to the FAA on April 01, 2019.

4 conditions:

1. Design changes proposed by Boeing are EASA approved (no delegation to FAA)
2. Additional and broader independent design review has been satisfactorily completed by EASA
3. Accidents of JT610 and ET302 are deemed sufficiently understood
4. B737 MAX flight crews have been adequately trained

Seems there is some room for negotiation, but it's hard to say exactly who is deeming what sufficient understanding is, and how that party can get that understanding without being allowed full access to the accident investigation data before it is public, and how can anyone else decide the deeming is sufficient without having public access to the accident reports?

EASA sure has put itself into the role of king maker, at the risk of becoming another untrusted party should their deeming prove to not be sufficient.


I have bolded a part of your statements:

It is possible for the EASA and select other parties to be granted "view selected parts only" or "observer" status to a root cause investigation; if they are deemed to have sufficient legitimate interest and appropriately agree to the NDA agreement. As such, it is possible that EASA has direct access to the key information from both the crash investigations; and, perhaps not.

I would agree that EASA would put themselves into a "less trustworthy" status by requiring the public results reports to be issued, which often take 12-18 months. Imagine the havoc created in the aviation world if aircraft were grounded after accidents until the public report was issued.

I believe that the EASA is aware of this potential (which is why the used the "sufficiently understood" terminology they did). How they satisfy themselves that the crashes are satisfactory understood unless they have been granted access to the relevant data by the investigation boards is clearly an issue; and a potential issue that they themselves have created. It would not look good if much of the rest of the world allows RTS shortly after FAA approval and EASA does not.

Have a great day,
 
IADFCO
Posts: 128
Joined: Sun May 22, 2016 4:20 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 2:33 pm

Critical as I have been of Boeing and the FAA, still, let's not get carried away. My concern, as a passenger who may not have much choice one or two years from now but flying in a MAX, and as an aerospace engineer, is that there is more to the aerodynamic problems of the MAX than just the stick lightening and a small hiccup in certification, fixable by the MCAS. My concern is that the stall entry and recovery characteristics of the MAX are substantially worse than those of the NG, because of the nacelle-wing leading edge aerodynamic interference (not the extra nacelle lift). Mine is an informed speculation, based on available factual information and leaks, but still a speculation.

If my concern is unfounded, and it's just really a stick lightening issue, MCAS 2.0 will work. For the windup turn issue I would increase the number of activations from one to two to cover 25 seconds of MCAS protection (2 cycles of 10 sec of MCAS on + 5 sec MCAS off) which should be enough for any conceivable evasive maneuver. Maybe add a big flashing "MCAS OFF" red light.

If my concern is founded, i.e., the MAX cannot go anywhere near stall, then the situation is much more serious, because then MCAS has to really take an envelope protection function, and we also know that the consequences of some malfunctions can be catastrophic (i.e.,10E-9 failure rate territory). Still, even in this case, if the F-117 flies, anything can fly, and the MAX is nowhere near that aerodynamic nightmare. It would require some more extensive redesign of the flight control system, but the engineering talent is there, unless they laid off all the people who designed the 777 and 787 flight control systems.
 
asdf
Posts: 435
Joined: Tue Mar 18, 2014 12:03 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 2:48 pm

[quote="mjoelnir"]IMO one should think about how manual electrical trim is done in a 737NG or MAX before the now advertised changes are done.
The inputs from the switches are not to the trim motor relay, but into a computer. /quote]

no computer here AFAIK @ the 737
this is simple point 2 point electronics (if not even electrics)

only if you have a FBW plane all control inputs go into a computer
the computer is connected to all sensors

the computer alone is calculating the movement of surfaces and the power of engines
almost every sensor is tripple redundant

no such system @ the 737 at all
 
User avatar
seahawk
Posts: 8704
Joined: Fri May 27, 2005 1:29 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 3:01 pm

hooverman wrote:
seahawk wrote:
The FAA will test all this and the MAX will be the safest plane it its class when it returns to service early October.


October? What airline? Worldwide?


When the FAA has given the green light there is no reason for others to ground the plane.The whole industry suffers if the leading authorities start second guessing each other. So unless the FAA has rejected reasonable concerns by EASA, the EASA should not delay.
 
2175301
Posts: 1505
Joined: Wed May 16, 2007 11:19 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 3:06 pm

gregpodpl wrote:
seahawk wrote:
The FAA will test all this and the MAX will be the safest plane it its class when it returns to service early October.

Is the class "planes that killed 300 people in last year" ?


I'm not sure you understand how big is this classification: A quick review of crash data of aircraft that have been involved in crashes that killed 300 people in a 12 month window produces the following list:

By Family designation (multiple sub derivatives); with the 737 Family being split for clarification of the issue:
A320
B707
B727 - Edited to add later (not sure how I forgot this)
B737 (Classic)
B737 (Max)
B747
B777 Note: MH17 & MH370
DC10

lower the number to say 200 or 250 in a 12 month window and other aircraft gets added.

To the best of my knowledge, extremely few people are afraid to fly these aircraft families today... (I'm don't believe there are any B707, B727, or DC10's left in passenger service - perhaps an isolated few).

Have a great day
Last edited by 2175301 on Fri Sep 06, 2019 3:25 pm, edited 1 time in total.
 
Amiga500
Posts: 2318
Joined: Tue Mar 03, 2015 8:22 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 3:24 pm

seahawk wrote:
The FAA will test all this and the MAX will be the safest plane it its class when it returns to service early October.


Image

You catching much this weather?
 
XRAYretired
Posts: 623
Joined: Fri Mar 15, 2019 11:21 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 3:25 pm

2175301 wrote:
gregpodpl wrote:
seahawk wrote:
The FAA will test all this and the MAX will be the safest plane it its class when it returns to service early October.

Is the class "planes that killed 300 people in last year" ?


I'm not sure you understand how big is this classification: A quick review of crash data of aircraft that have been involved in crashes that killed 300 people in a 12 month window produces the following list:

By Family designation (multiple sub derivatives); with the 737 Family being split for clarification of the issue:
A320
B707
B727 - Edited to add later (not sure how I forgot this)
B737 (Classic)
B737 (Max)
B747
DC10

lower the number to say 200 or 250 in a 12 month window and other aircraft gets added.

To the best of my knowledge, extremely few people are afraid to fly these aircraft families today... (I'm don't believe there are any B707, B727, or DC10's left in passenger service - perhaps an isolated few).

Have a great day

Please don't start all this rubbish again. Its been through the mill more times than I care to remember and serves no useful purpose. The thread is related to 737 max crash/grounding and RTS.
 
Amiga500
Posts: 2318
Joined: Tue Mar 03, 2015 8:22 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 3:25 pm

seahawk wrote:
When the FAA has given the green light there is no reason for others to ground the plane.The whole industry suffers if the leading authorities start second guessing each other. So unless the FAA has rejected reasonable concerns by EASA, the EASA should not delay.


Ahh, a change of bait.

Still, don't try too hard - otherwise the waters are muddied and you'll not catch much.

Image
 
frmrCapCadet
Posts: 3129
Joined: Thu May 29, 2008 8:24 pm

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 3:42 pm

Some requirements of regulatory bodies require immediate action, others are on a defined schedule in the future. EASA could do such a thing. I have no idea as to what they will do.
Buffet: the airline business...has eaten up capital...like..no other (business)
 
XRAYretired
Posts: 623
Joined: Fri Mar 15, 2019 11:21 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 3:45 pm

Amiga500 wrote:
seahawk wrote:
When the FAA has given the green light there is no reason for others to ground the plane.The whole industry suffers if the leading authorities start second guessing each other. So unless the FAA has rejected reasonable concerns by EASA, the EASA should not delay.


Ahh, a change of bait.

Still, don't try too hard - otherwise the waters are muddied and you'll not catch much.

Image

Ground bait attracts the little fishes.
 
User avatar
seahawk
Posts: 8704
Joined: Fri May 27, 2005 1:29 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 3:52 pm

Amiga500 wrote:
seahawk wrote:
When the FAA has given the green light there is no reason for others to ground the plane.The whole industry suffers if the leading authorities start second guessing each other. So unless the FAA has rejected reasonable concerns by EASA, the EASA should not delay.


Ahh, a change of bait.

Still, don't try too hard - otherwise the waters are muddied and you'll not catch much.

Image


I think it is a serious concern. Nobody is helped by leading authorities mistrusting each other. If the FAA handles the EASA concerns in reasonable and professional matter, EASA should not delay their decision. Nobody should want to go back to the old days, where you had to put your plane through a full certification process with different authorities with changing requirements and vastly different processes.
 
User avatar
Erebus
Posts: 1044
Joined: Tue Oct 20, 2015 2:40 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 4:14 pm

seahawk wrote:
Nobody is helped by leading authorities mistrusting each other.


Nobody is helped if the industry abuses each others' trust (or be allowed to). We are where we are with the MAX exactly because of this.
 
bennett123
Posts: 8945
Joined: Sun Aug 15, 2004 12:49 am

Re: Boeing 737MAX Grounded Worldwide Q3 2019

Fri Sep 06, 2019 4:27 pm

Iirc, the FAA only grounded it following an Executive Order.

Trust has to be earned.

Popular Searches On Airliners.net

Top Photos of Last:   24 Hours  •  48 Hours  •  7 Days  •  30 Days  •  180 Days  •  365 Days  •  All Time

Military Aircraft Every type from fighters to helicopters from air forces around the globe

Classic Airliners Props and jets from the good old days

Flight Decks Views from inside the cockpit

Aircraft Cabins Passenger cabin shots showing seat arrangements as well as cargo aircraft interior

Cargo Aircraft Pictures of great freighter aircraft

Government Aircraft Aircraft flying government officials

Helicopters Our large helicopter section. Both military and civil versions

Blimps / Airships Everything from the Goodyear blimp to the Zeppelin

Night Photos Beautiful shots taken while the sun is below the horizon

Accidents Accident, incident and crash related photos

Air to Air Photos taken by airborne photographers of airborne aircraft

Special Paint Schemes Aircraft painted in beautiful and original liveries

Airport Overviews Airport overviews from the air or ground

Tails and Winglets Tail and Winglet closeups with beautiful airline logos