Go Back  PPRuNe Forums > Flight Deck Forums > Rumours & News
Reload this Page >

MAX’s Return Delayed by FAA Reevaluation of 737 Safety Procedures

Rumours & News Reporting Points that may affect our jobs or lives as professional pilots. Also, items that may be of interest to professional pilots.

MAX’s Return Delayed by FAA Reevaluation of 737 Safety Procedures

Old 1st Dec 2019, 20:33
  #4201 (permalink)  
 
Join Date: Jan 2008
Location: Reading, UK
Posts: 11,038
Originally Posted by JeroenD View Post
What will happen with the 737 Max’s that are grounded overseas? Will the FAA need to send staff there, or do they need to fly those planes back to the USA to get their certificate?
AFAIK, there are no undelivered Max aircraft being stored outside the USA.

DaveReidUK is offline  
Old 1st Dec 2019, 21:29
  #4202 (permalink)  
 
Join Date: Mar 2019
Location: French Alps
Posts: 325
Originally Posted by DaveReidUK View Post
AFAIK, there are no undelivered Max aircraft being stored outside the USA.
Yes but there are grounded MAX.
Why would planes having flown a few hundreds hours escape the recertification undelivered planes with a few flight hours would undergo ?
Will they be left to Boeing's 'oversight' ?
Fly Aiprt is offline  
Old 1st Dec 2019, 21:48
  #4203 (permalink)  
 
Join Date: Oct 2019
Location: USA
Posts: 107
That requirement should be per each country of registration Civil Aeronautics organization to determine as well as the carrier's insurance. I expect that any plane that Boeing is not allowed to modify to the FAA and EASA re-certification requirements will also not be allowed in most air spaces and the carrier will not be allowed any spare parts or other product support.
MechEngr is offline  
Old 1st Dec 2019, 22:06
  #4204 (permalink)  
Thread Starter
 
Join Date: Apr 2015
Location: Under the radar, over the rainbow
Posts: 625
Originally Posted by MechEngr View Post
That requirement should be per each country of registration Civil Aeronautics organization to determine as well as the carrier's insurance. I expect that any plane that Boeing is not allowed to modify to the FAA and EASA re-certification requirements will also not be allowed in most air spaces and the carrier will not be allowed any spare parts or other product support.
Yup. Given the messages we've been seeing from other CAAs, it's probably a pretty safe bet that those airplanes grounded outside the US will receive (at least) the same level of vigorous regulatory scrutiny as the ones stashed here.
OldnGrounded is offline  
Old 1st Dec 2019, 23:29
  #4205 (permalink)  
 
Join Date: Jan 2008
Location: Reading, UK
Posts: 11,038
Originally Posted by Fly Aiprt View Post
Yes but there are grounded MAX.
Why would planes having flown a few hundreds hours escape the recertification undelivered planes with a few flight hours would undergo ?
Two different things.

The aircraft already delivered will, by definition, have been issued with C of As, albeit they can't currently fly because there's an AD grounding the type.

Undelivered aircraft, on the other hand, won't be able to fly even after the grounding of the type is lifted, until they get a C of A.

Obviously both groups will be subject to any AD issued to require implementation of post-MCAS mods, but that's a different issue.
DaveReidUK is offline  
Old 1st Dec 2019, 23:44
  #4206 (permalink)  
 
Join Date: Mar 2019
Location: French Alps
Posts: 325
Originally Posted by DaveReidUK View Post
Two different things.

The aircraft already delivered will, by definition, have been issued with C of As, albeit they can't currently fly because there's an AD grounding the type.

Undelivered aircraft, on the other hand, won't be able to fly even after the grounding of the type is lifted, until they get a C of A.

Obviously both groups will be subject to any AD issued to require implementation of post-MCAS mods, but that's a different issue.
I beg to differ : both category of aircraft have been built and flown under the same C of A. The fact that some were to be delivered - as opposed as had already been delivered - doesn't change the issue.
Where do you draw the line ?
Some of the 'undelivered' aircraft are already owned by client airlines.
Or do you make a difference because some have already flown passengers ?
Fly Aiprt is offline  
Old 1st Dec 2019, 23:55
  #4207 (permalink)  
 
Join Date: Nov 2007
Location: dublin
Posts: 1
Originally Posted by Dave Therhino View Post
At MCT at low altitude in a 737 you have maybe 7-10 seconds of fuel in the lines before the engines flame out if you were to attempt sustained inverted flight.
Hi Dave
in the sim you can fly a 737 compete circuit inverted and roll out on final to a safe landing. Was taught this by one of our Red Bull pilots. But of course the engines would flame out so it wouldn’t work in reality
barell roll or Chantelle easy on sim
loop we managed by getting weight down to APS plus two tones, diving to vmo and going for it. Worked a treat.
All of this of course depended on the modeling that was programmed but out Red Bull guy thought it pretty realistic
cheers
Jan
yanrair is offline  
Old 2nd Dec 2019, 02:36
  #4208 (permalink)  
Psychophysiological entity
 
Join Date: Jun 2001
Location: Tweet Rob_Benham Famous author. Well, slightly famous.
Age: 80
Posts: 4,761
During the course of these threads, I've often wondered if mobilizing the passengers would have worked - given available time. It would of course have meant a lot of loose passengers, their lives being put into immediate jeopardy, but the thought of bellowing over the PA to get as many hefty people to the rear teases at my more serious thought processes.

I've planned it with jammed elevator, but everything was calm and there were only 20 sob.

Aerobatic jet transport aircraft? Well, I'm not very proud of this, but in a BAC 1-11, having had a finger thrust across my face with 'MIND THAT!!!' I rolled to the right with I suppose the energy derived from surprise/shock. We'd taken with a pinch of salt BAC's trainer's 'It'll roll as fast as a Lightning' but the thing was passing 95 degrees in not much more than a second. (cruising at FL 80) The spoiler would actuate on the Up aileron side. There were engineers on board but no passengers. There is no doubt the aircraft would have been on its back in less than 3 seconds. During training, I'd been strongly encouraged to try the rate of roll. Several times. It seems that without the fear factor, it was good, but comparatively staid. For a couple of years, I'd had no idea what it was really capable of.

Given the speed of the ET, the g force would have been horrible -2g change before the geometric force was added. But when it was getting to a last-ditch battle, I think there was just a chance it would have worked.

On the first crash, the aircraft took that sudden excursion into a steep climb anyway. I'm still not certain how that came about, though there was a large increase in fuel flow just prior. We do know it wasn't rolled . . . don't we?
Loose rivets is offline  
Old 2nd Dec 2019, 02:48
  #4209 (permalink)  
 
Join Date: Jul 2013
Location: Everett, WA
Age: 64
Posts: 2,558
Originally Posted by Fly Aiprt View Post
I beg to differ : both category of aircraft have been built and flown under the same C of A. The fact that some were to be delivered - as opposed as had already been delivered - doesn't change the issue.
Where do you draw the line ?
Some of the 'undelivered' aircraft are already owned by client airlines.
Or do you make a difference because some have already flown passengers ?
In short, you're wrong. Every new aircraft gets approved - "ticketed" - by the FAA before it can be delivered - and it's done on an aircraft by aircraft basis. An aircraft can't be ticketed if there is an outstanding AD that hasn't been complied with, so by definition the hundreds of aircraft Boeing has sitting around Boeing Field, Moses Lake, etc. have not been ticketed (note, there may be a handful of aircraft that were ticketed but not delivered when the grounding took effect, but only a few). It's this pre-delivery approval ('ticket') that the FAA will be withholding pending further inspection - which is their prerogative.
However, any aircraft that has been delivered has - again by definition - been ticketed. Once ticketed (even if it's later determined to have been ticketed in error), an aircraft can't be 'un-ticketed'. However it can be grounded by an AD. Ticketing a new aircraft 'in error' has pretty serious repercussions for the manufacturer (I had the rather unpleasant experience of being involved in one of those).
tdracer is offline  
Old 2nd Dec 2019, 03:44
  #4210 (permalink)  
 
Join Date: Jan 2013
Location: Seattle Area
Posts: 154
TD - I think he's confusing type certification with issuance of a new airworthiness.

Some of your details weren't correct:

Every aircraft delivered out of the Boeing production system receives either a new standard airworthiness certificate or an export certificate of airworthiness. All flying done prior to the issuance of one of those types of certificates is done under an experimental certificate issued for one or more stated purposes (R&D, show compliance, crew training, etc.) or under a special flight permit for production acceptance testing. Both an experimental certificate and a special flight permit are forms of special airworthiness certificate. An aircraft can receive a standard C of A if the inspector judges the airplane is "in condition for safe operation," so for the most part any AD for which a notice of public rule making (NPRM) was issued and a long compliance time is set does not necessarily need to be complied with prior to the AD's compliance deadline. It's decided case by case and is up to the inspector in consultation with the ODA and FAA. Export can be more problematic if the receiving country insists on full AD compliance. Of course, the customer prefers the AD work be completed before delivery and Boeing usually does it if they can. An airworthiness certificate can be surrendered, suspended, revoked, or terminated via an expiration date if one is set in the certificate.

Last edited by Dave Therhino; 2nd Dec 2019 at 05:34. Reason: correction to include special flight permits
Dave Therhino is offline  
Old 2nd Dec 2019, 04:26
  #4211 (permalink)  
 
Join Date: Jul 2013
Location: Everett, WA
Age: 64
Posts: 2,558
Dave, we're probably debating minutia here, although I agree Fly is confusing type cert with the aircraft specific airworthiness certificate - what we always referred to as being 'ticketed'. An airworthiness certificate can not be issued if the aircraft is out of compliance with an existing AD (agreed, if the required compliance date is in the future, then the certificate can be granted based on a plan to comply by the compliance date). However since the corrective action for the MAX is (so far) undefined, compliance can not be shown hence no new production aircraft can be ticketed.
Unless something has changed since I retired, I do disagree about production flight testing normally being done on an experimental ticket - so long as the aircraft complied with the approved type design, they did normal production flight test under the production certificate. I ran into this because when we wanted to flight test something new - it wasn't per the type design so it needed an experimental ticket (and production always complained about the paperwork they needed to do to get the EX ticket) - at which time it became an experimental flight test, not production flight test (although we often did some production flight testing on our experimental flight tests). That being said, I suspect all the current MAX production flight testing is being done via experimental tickets since they can't be shown to be compliant with the existing AD.
tdracer is offline  
Old 2nd Dec 2019, 05:06
  #4212 (permalink)  
568
 
Join Date: Aug 2002
Location: Castletown
Posts: 128
Originally Posted by tdracer View Post
Dave, we're probably debating minutia here, although I agree Fly is confusing type cert with the aircraft specific airworthiness certificate - what we always referred to as being 'ticketed'. An airworthiness certificate can not be issued if the aircraft is out of compliance with an existing AD (agreed, if the required compliance date is in the future, then the certificate can be granted based on a plan to comply by the compliance date). However since the corrective action for the MAX is (so far) undefined, compliance can not be shown hence no new production aircraft can be ticketed.
Unless something has changed since I retired, I do disagree about production flight testing normally being done on an experimental ticket - so long as the aircraft complied with the approved type design, they did normal production flight test under the production certificate. I ran into this because when we wanted to flight test something new - it wasn't per the type design so it needed an experimental ticket (and production always complained about the paperwork they needed to do to get the EX ticket) - at which time it became an experimental flight test, not production flight test (although we often did some production flight testing on our experimental flight tests). That being said, I suspect all the current MAX production flight testing is being done via experimental tickets since they can't be shown to be compliant with the existing AD.
Could it also be a special flight permit for certain flights?
Thought B1 flights out of Renton were on the exp cert anyway?
568 is offline  
Old 2nd Dec 2019, 05:31
  #4213 (permalink)  
 
Join Date: Jan 2013
Location: Seattle Area
Posts: 154
I double checked the requirements and I had used "experimental certificate" for one case where I should have used "special flight permit." Both are forms of special airworthiness certificate. I'll change my response above so I don't leave bad information in place.

If Boeing was doing only normal production flight tests on the airplane in the situation you (TD) mentioned, they would have been under a special airworthiness certificate known as a special flight permit. When you proposed experimental flying, they would have had to apply for an experimental certificate. If they were doing compliance showing or other activities that already required an experimental certificate, but the special purposes stated on the certificate did not include R&D, again they would have had to re-apply to have the experimental certificate reissued. Part of the process in either case is yelling at the engineer who brings the bad news about the paperwork involved ;-).

See 14 CFR 91.203(a) for the regulatory requirement that calls for these certificates. Paraphrasing, no person may operate a civil aircraft unless it has within it an appropriate C of A and a registration certificate. That regulation applies to Boeing's production flight testing activity. See 14 CFR 21.197 for the authorization to use a special flight permit (again, a form of special airworthiness certificate) for manufacturer production acceptance testing.

Last edited by Dave Therhino; 2nd Dec 2019 at 07:58. Reason: clarified "you" meant tdracer because another response was posted in the interim
Dave Therhino is offline  
Old 2nd Dec 2019, 06:53
  #4214 (permalink)  

Keeping Danny in Sandwiches
 
Join Date: May 1999
Location: UK
Age: 71
Posts: 1,279
I was going through the Boeing update on the MAX and came across their definitions page
https://www.boeing.com/commercial/73...e-updates.page
Their definition is interesting:
Angle of Attack (AOA) – the difference between the pitch angle (nose direction) of the airplane and the angle of the oncoming wind.

I was never aware that the AOA measured wind; I always thought in 35 years of flying that it measured the angle of the oncoming airflow. To think I spent my whole aviation career with a misapprehension.
sky9 is offline  
Old 2nd Dec 2019, 08:59
  #4215 (permalink)  
 
Join Date: Mar 2002
Location: EU
Posts: 586
Originally Posted by sky9 View Post
I was going through the Boeing update on the MAX and came across their definitions page
https://www.boeing.com/commercial/73...e-updates.page
Their definition is interesting:
Angle of Attack (AOA) – the difference between the pitch angle (nose direction) of the airplane and the angle of the oncoming wind.

I was never aware that the AOA measured wind; I always thought in 35 years of flying that it measured the angle of the oncoming airflow. To think I spent my whole aviation career with a misapprehension.
and it isn’t referenced to pitch angle either
golfyankeesierra is offline  
Old 2nd Dec 2019, 09:16
  #4216 (permalink)  

Keeping Danny in Sandwiches
 
Join Date: May 1999
Location: UK
Age: 71
Posts: 1,279
and it isn’t referenced to pitch angle either
Wonder what else these experts got wrong?
Collins Dictionary refer to it as
the acute angle between the chord line of an aerofoil and the undisturbed relative airflow which would seem about right to me.
In their Aero Magazine they get it right as well other than the use of the word wind.
http://www.boeing.com/commercial/aer.../whatisaoa.pdf
Angle of attack (AOA) is the angle between the oncoming air or relative wind and a reference line on the airplane or wing. Sometimes, the reference line is a line connecting the leading edge and trailing edge at some average point on the wing. Most commercial jet airplanes use the fuselage centerline or longitudinal axis as the reference line. It makes no difference what the reference line is, as long as it is used consistently. AOA is sometimes confused with pitch angle or flight path angle. Pitch angle (attitude) is the angle between the longitudinal axis (where the airplane is pointed) and the horizon. This angle is displayed on the attitude indicator or artificial horizon.

Last edited by sky9; 2nd Dec 2019 at 09:54. Reason: Added information
sky9 is offline  
Old 2nd Dec 2019, 12:53
  #4217 (permalink)  
 
Join Date: Mar 2014
Location: Dallas
Age: 62
Posts: 8
Tex Johnson, in a demonstration flight for Boeing, flew a barrel roll. in a 707. It's probably mentioned in his autobiography "Tex Johnston: Jet Test Pilot". There are a couple of youtube video's of it.

The ET302 pilots were eventually at high speed. MCAS firing for 10 seconds, using the high speed setting of the trim motor, must have been quite a pitch down force. I don't think 737 pilots would have been used to correcting so much of a trim change. They were used to speed trim changing things gradually. One of the Lion Air flights, I think fought with MCAS for 20 times or so? Then he gave the plane to the FO, who not focused on the Capt.'s yoke switch as he had other things he was busy with, didn't use as much trim response to MCAS, as he probably thought it was speed trim he was correcting for, not knowing MCAS was there. Both of the Lion Air FO's did the same thing initially when given the controls. They under corrected for MCAS changes. Who puts in 10 seconds of trim change, all at once, going at high speed in a 737?
GroundedDinosaur is offline  
Old 2nd Dec 2019, 13:05
  #4218 (permalink)  
 
Join Date: Mar 2019
Location: French Alps
Posts: 325
Originally Posted by tdracer View Post
Dave, we're probably debating minutia here, although I agree Fly is confusing type cert with the aircraft specific airworthiness certificate - what we always referred to as being 'ticketed'. An airworthiness certificate can not be issued if the aircraft is out of compliance with an existing AD (agreed, if the required compliance date is in the future, then the certificate can be granted based on a plan to comply by the compliance date).
Td and all,
Thanks for your responses. I'll agree we're discussing minutiae, and it doesn't change much to the situation.
Like - I suppose - some others I was under the impression that the type certificate was questioned, Cf Leeham talking about "recertifying the MAX", and this was the question in debate.

Fly Aiprt is offline  
Old 2nd Dec 2019, 13:25
  #4219 (permalink)  
 
Join Date: Mar 2019
Location: On the Ground
Posts: 152
Originally Posted by GroundedDinosaur View Post
Who puts in 10 seconds of trim change, all at once, going at high speed in a 737?
Boeing does.

Takwis is offline  
Old 2nd Dec 2019, 14:12
  #4220 (permalink)  
Thread Starter
 
Join Date: Apr 2015
Location: Under the radar, over the rainbow
Posts: 625
Originally Posted by Takwis View Post
Boeing does.
In secret.
OldnGrounded is offline  

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information

Copyright © 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.