Boeing in yet another technical pickle!

Message
Author
User avatar
Rwy in Sight
Chief Pilot
Chief Pilot
Posts: 6740
Joined: Wed Aug 26, 2015 8:04 pm
Location: Lost in an FIR somewhere
Gender:

Re: Boeing in yet another technical pickle!

#61 Post by Rwy in Sight » Tue Oct 29, 2019 8:50 pm

It might have been mentioned beforehand but I failed to spot it so I am pleading any kind soul to explain it to me: what was the reasoning behind the installation of a single sensor vs a more reliable structure?

Pontius Navigator
Chief Pilot
Chief Pilot
Posts: 14669
Joined: Fri Jul 07, 2017 8:17 am
Location: Gravity be the clue
Gender:
Age: 80

Re: Boeing in yet another technical pickle!

#62 Post by Pontius Navigator » Tue Oct 29, 2019 9:22 pm

Probably in TGGs link. I would guess economy.

User avatar
Undried Plum
Chief Pilot
Chief Pilot
Posts: 7308
Joined: Sun Jul 22, 2018 8:45 pm
Location: 56°N 4°W

Re: Boeing in yet another technical pickle!

#63 Post by Undried Plum » Tue Oct 29, 2019 10:33 pm

Image

User avatar
boing
Chief Pilot
Chief Pilot
Posts: 2714
Joined: Thu Aug 27, 2015 6:32 am
Location: Beautful Oregon USA
Gender:
Age: 77

Re: Boeing in yet another technical pickle!

#64 Post by boing » Wed Oct 30, 2019 1:54 am

As reported in another article, linked by TGG I think, adding a second AoA vane could have then meant that a third vane would be needed as a tie-breaker - so over triple the expense. The clutz solution was to simply use a light to tell the pilots there was an AoA discrepancy, it still did not tell them which one had failed and this system did not activate until 400 feet after take-off because AoA vanes commonly flop all over the place until they feel some airflow. So you get airborne then when you are busy shortly after take-off the damn light comes on. Thanks.


.
the dreamers of the day are dangerous men, for they may act on their dreams with open eyes, to make them possible.

User avatar
Rwy in Sight
Chief Pilot
Chief Pilot
Posts: 6740
Joined: Wed Aug 26, 2015 8:04 pm
Location: Lost in an FIR somewhere
Gender:

Re: Boeing in yet another technical pickle!

#65 Post by Rwy in Sight » Wed Oct 30, 2019 6:41 am

boing wrote:
Wed Oct 30, 2019 1:54 am
As reported in another article, linked by TGG I think, adding a second AoA vane could have then meant that a third vane would be needed as a tie-breaker - so over triple the expense. The clutz solution was to simply use a light to tell the pilots there was an AoA discrepancy, it still did not tell them which one had failed and this system did not activate until 400 feet after take-off because AoA vanes commonly flop all over the place until they feel some airflow. So you get airborne then when you are busy shortly after take-off the damn light comes on. Thanks.
I am not sure I understand the economy, in hindsight I must add. A Max is around what 80 mil? Even if the additional equipment (two more vanes) cost a 5 figure sum it wouldn't make a difference on the final price tag and maintenance cost. Obviously currently Boeing wish they offered the full set for free.

User avatar
TheGreenGoblin
Chief Pilot
Chief Pilot
Posts: 17596
Joined: Thu Aug 08, 2019 11:02 pm
Location: With the Water People near Trappist-1

Re: Boeing in yet another technical pickle!

#66 Post by TheGreenGoblin » Wed Oct 30, 2019 9:16 am

boing wrote:
Wed Oct 30, 2019 1:54 am
As reported in another article, linked by TGG I think, adding a second AoA vane could have then meant that a third vane would be needed as a tie-breaker - so over triple the expense. The clutz solution was to simply use a light to tell the pilots there was an AoA discrepancy, it still did not tell them which one had failed and this system did not activate until 400 feet after take-off because AoA vanes commonly flop all over the place until they feel some airflow. So you get airborne then when you are busy shortly after take-off the damn light comes on. Thanks.
The whole AoA vane solution, even triply redundant with electronic discrepancy and tie -break voting, due to an intrinsic design problem with the aircraft, smacks of being an unholy kludge!

Yep I know that many aircraft have had analogue or electronic fixes to help "iron out" unpleasant or potentially deadly handling issues (think stick shaker on the BAC One-Eleven for example) but this AoA vane remediation seems so totally crass. How any engineer could have felt comfortable with it just boggles the mind.

https://en.wikipedia.org/wiki/1963_BAC_ ... test_crash
Though you remain
Convinced
"To be alive
You must have somewhere
To go
Your destination remains
Elusive."

Boac
Chief Pilot
Chief Pilot
Posts: 17209
Joined: Fri Aug 28, 2015 5:12 pm
Location: Here

Re: Boeing in yet another technical pickle!

#67 Post by Boac » Wed Oct 30, 2019 12:18 pm

I don't know how many of you follow Juan Browne's series of youtube videos on the max problems, but his latest on the Max hearing is well worth watching.

User avatar
TheGreenGoblin
Chief Pilot
Chief Pilot
Posts: 17596
Joined: Thu Aug 08, 2019 11:02 pm
Location: With the Water People near Trappist-1

Re: Boeing in yet another technical pickle!

#68 Post by TheGreenGoblin » Wed Oct 30, 2019 12:23 pm

Boac wrote:
Wed Oct 30, 2019 12:18 pm
I don't know how many of you follow Juan Browne's series of youtube videos on the max problems, but his latest on the Max hearing is well worth watching.
+1
Though you remain
Convinced
"To be alive
You must have somewhere
To go
Your destination remains
Elusive."

User avatar
boing
Chief Pilot
Chief Pilot
Posts: 2714
Joined: Thu Aug 27, 2015 6:32 am
Location: Beautful Oregon USA
Gender:
Age: 77

Re: Boeing in yet another technical pickle!

#69 Post by boing » Wed Oct 30, 2019 4:30 pm

I have flown two "antique" aircraft that had stability augmentation so the concept is not new, in fact the systems I am thinking of would now be considered crude but they were "safe".

This disaster boils down to the interpretation of what constitutes a new aircraft type as far as certification is concerned because a new aircraft type involves increased manufacturing costs and increased operating costs. In my experience the "similar type" philosophy first appeared with the 767 where two similar variants of the aircraft were covered by one type rating even though the aircraft had different engines, originally a different number of crew members and many different check-list procedures. There may have been earlier examples. Since then the concept of "new model but same type" has been a prime approach in the industry to reduce costs and the interpretation of "similar" has been stretched considerably. The result has been pushing the boundary between "similar type" and "new type".

And herein lies the 737MAX problem. If the 737MAX certification had crossed the line into requiring full certification it would have been a more expensive aircraft for the airlines to buy and operate. So Boeing simply hid the triggers that MAY have required re-certification and MCAS was apparently, based on Boeing's obfuscation, a sensitive item.

Boeing made a business decision. Whoops, we have a problem, the new design either needs longer gear legs to fit the engines in the optimum place under the wings or we will have to go with some sort of stability augmentation to make it behave like the older 737s. A new design was out of the question because structural changes would certainly need re-certification so lets go with the stab. system. The result was that they went with a cheap and nasty stab. system and tried to hide it in case it led to extra crew training requirements that may have led to the aircraft being considered as a separate type.

Now, much has been done in the area of pilot training to reduce it to a matter of sitting down in front of a computer, listening to the course material and then taking the multiple choice test but Boeing could not guarantee to themselves that even the FAA would buy into this training when immediate check-list actions and flying procedures were involved so they simply hid the problem. They hid the problem since the extra training would remove the 737MAX from the "similar" aircraft provision and require that it only be flown by suitably trained pilots which meant that an airline would have to train ALL of its 737 pilots on the MAX or create a special group of MAX only pilots. This would lead to increased crewing and training costs.

The rest is history still in the making.


.
the dreamers of the day are dangerous men, for they may act on their dreams with open eyes, to make them possible.

User avatar
TheGreenGoblin
Chief Pilot
Chief Pilot
Posts: 17596
Joined: Thu Aug 08, 2019 11:02 pm
Location: With the Water People near Trappist-1

Ryanair grounds three 737's due to cracks...

#70 Post by TheGreenGoblin » Wed Nov 06, 2019 6:08 am

Cracks between the wing the fuselage
At least three Ryanair Boeing 737s have been grounded due to cracks between the wing and fuselage but this was not disclosed to the public, the Guardian can reveal.
The budget Irish airline is the latest to be affected by faults in the “pickle fork” structure, which has sparked an urgent grounding of 50 planes globally since 3 October.
Though you remain
Convinced
"To be alive
You must have somewhere
To go
Your destination remains
Elusive."

Boac
Chief Pilot
Chief Pilot
Posts: 17209
Joined: Fri Aug 28, 2015 5:12 pm
Location: Here

Re: Boeing in yet another technical pickle!

#71 Post by Boac » Wed Nov 20, 2019 9:45 am

..and the woeing for Boeing goes on https://samchui.com/2019/11/20/ntsb-sug ... dUKUdXgqcQ

User avatar
ian16th
Chief Pilot
Chief Pilot
Posts: 10029
Joined: Fri Aug 28, 2015 9:35 am
Location: KZN South Coast with the bananas
Gender:
Age: 87

Re: Boeing in yet another technical pickle!

#72 Post by ian16th » Wed Nov 20, 2019 10:24 am

Boac wrote:
Wed Nov 20, 2019 9:45 am
..and the woeing for Boeing goes on https://samchui.com/2019/11/20/ntsb-sug ... dUKUdXgqcQ
That'll cost a few bob!
Cynicism improves with age


User avatar
TheGreenGoblin
Chief Pilot
Chief Pilot
Posts: 17596
Joined: Thu Aug 08, 2019 11:02 pm
Location: With the Water People near Trappist-1

Re: Boeing in yet another technical pickle!

#74 Post by TheGreenGoblin » Wed Nov 20, 2019 7:20 pm

An excellent article. Many thanks for posting that.
Though you remain
Convinced
"To be alive
You must have somewhere
To go
Your destination remains
Elusive."

User avatar
Fox3WheresMyBanana
Chief Pilot
Chief Pilot
Posts: 12987
Joined: Thu Sep 03, 2015 9:51 pm
Location: Great White North
Gender:
Age: 61

Re: Boeing in yet another technical pickle!

#75 Post by Fox3WheresMyBanana » Wed Nov 20, 2019 8:15 pm

Staggering really, that a bunch of financiers thought they could run a major aerospace company from a thousand miles away. In the simplest terms, it is rocket science.

The history of business is that you can turn engineers into financiers. Indeed, one third of my fellow engineering graduates went straight off to do finance, as usual.

You cannot turn accountants into anything, not even bankers.
And certainly not lion tamers :D


User avatar
llondel
Chief Pilot
Chief Pilot
Posts: 5913
Joined: Wed Oct 03, 2018 3:17 am
Location: San Jose

Re: Boeing in yet another technical pickle!

#76 Post by llondel » Wed Nov 20, 2019 8:47 pm

Fox3WheresMyBanana wrote:
Wed Nov 20, 2019 8:15 pm
You cannot turn accountants into anything, not even bankers.
And certainly not lion tamers :D
But one should encourage them to try...

User avatar
Fox3WheresMyBanana
Chief Pilot
Chief Pilot
Posts: 12987
Joined: Thu Sep 03, 2015 9:51 pm
Location: Great White North
Gender:
Age: 61

Re: Boeing in yet another technical pickle!

#77 Post by Fox3WheresMyBanana » Wed Nov 20, 2019 9:24 pm

Bit unfair on the lions, nasty taste ;)))

larsssnowpharter
Capt
Capt
Posts: 830
Joined: Thu Aug 23, 2018 3:31 pm
Location: United Kingdom
Gender:

Re: Boeing in yet another technical pickle!

#78 Post by larsssnowpharter » Wed Nov 20, 2019 9:26 pm

Thanks for posting that article from the Atlantic, Capt Slasher.

In the article and in others I have read, there is mention of acolytes of Jack Welch who came over or were recruited by Boeing.

I worked for GE in the late 90s during a period of rapid expansion. Not a nice outfit to work for in so many ways. Back then it was a ruthless business with what seemed to be just the one objective: to drive up the share price.
'Tis a great shame what has happened.
The only Boeing product I've flown was the Stearman and my memory is that Boeing had sold off production to Stearman. Still, a great fun aircrafts.

Boac
Chief Pilot
Chief Pilot
Posts: 17209
Joined: Fri Aug 28, 2015 5:12 pm
Location: Here

Update on the 737 NG flap track saga

#79 Post by Boac » Sat Dec 07, 2019 9:05 am


User avatar
barkingmad
Chief Pilot
Chief Pilot
Posts: 5497
Joined: Mon Nov 02, 2015 9:13 pm
Location: Another Planet
Gender:
Age: 75

Re: Boeing in yet another technical pickle!

#80 Post by barkingmad » Wed Dec 11, 2019 10:11 pm

777X FOLDING WINGTIPS! !

The military had many interesting experiences with these devices, mostly fatal.

Is this yet another tech pickle in gestation?

Post Reply