Boeing whistleblower shoots himself dead

[buzby]

I've just been for an MRI and googled what all of the sounds the machine makes are, which reminded me that I always mean to google what the loud squeaking sounds planes make before takeoff and after landing are.

Turns out it's only Airbuses that do it, and it tests our or initiates some hydraulic backup system they use - the Power Transfer Unit. I first assumed it was FLAPS, but I've looked for movement during the sounds in the past and seen nothing, like in this video:

The A319/A320/A321 family has 3 hydraulic systems for redundancy. The Green system pump is pressurised by a mechanical pump on engine no.1, the Yellow system has a mechanical pump on engine no.2 and a backup electrically-powered pump, and the Blue system has an electrical pump and a Ram Air Turbine that provides pressure if both engines shut down. The Power Transfer Unit is a bi-directional pump that mechanically links (it uses hydraulic pressure from one system to drive a pump to pressurise the other) the Green and Yellow systems and comes into action automatically if there is a significant pressure differential (500psi) between them:


In the case of that video, the PTU will have been operating to pressurise the Yellow hydraulic system in order to lower the flaps, which due to the number of actuators involved requires a large volume of pressurised fluid (and requires both the Green and Yellow systems). It looks like it is parked on a stand away from the terminal, so it will be the first movement of the day and it's usual to have only have one engine running (usually engine no.1) while on the ground to save fuel.

The hydraulic pressure in the systems will have drained down while it was parked and with only one engine running only the Green system will be pressurised, hence why the PTU runs for so long until the Yellow system and it's accumulator comes up to operating pressure so the flaps can be operated. It could have been avoided by turning on the electrically-driven pump for the Yellow hydraulic system (which is in some airline's procedures to save wear on the PTU and stop the racket it sends into the cabin).

As the PPRuNe threads state, the PTU shouldn't be heard running actually in flight unless the PTU's pressure sensors have a fault, one of the hydraulic pumps has an issue where it can't fully pressurise it's system or one system develops a leak.

[Glebe]

@touchingcloth Hope all good TC, vis-a-vis the MRI.

[touchingcloth]

@touchingcloth Hope all good TC, vis-a-vis the MRI.

Thanks, was just a routine one to keep tabs on my MS, and there's nothing like a visit to a neurology ward to reinforce how massively fortunate I am relative to some. I'm fine!

[MojoJojo]

They definitely did because the initial designs were so similar in dimension and specification, right down to the articulated cockpit.

However, the spying was uncovered and stopped before Concorde had perfected their wing and engine intake design. Delta wing designs are not good at relatively low speed take off and landing, you need to create vortices above the wing to generate enough lift. Concorde eventually found the perfect design, but the TU-144 instead had additional mini-wings above the cockpit that folded out during take off/landing to disturb the air, and folded away during cruise. The engine intake also helped Concorde burn fuel much more efficiently, whereas the TU-144 could only achieve supersonic flight for about an hour before running out.

The general proportions and droop nose are determined by aerodynamics though - the Boeing 2707 was the same*. And it's not as if they could just take the Concorde wings and slap them on - the Tu-144 was bigger and had very different engines, you couldn't just scale the wings up.

They did have the design of Concorde, and it makes a good story, but we'll never know how much it directly influenced the Tu-144. Probably the biggest argument against it being a direct copy is that the Soviets didn't need to copy -  the Tu-144 wasn't particularly innovative, and didn't feature anything Russia hadn't built before.

(*early on they planned swing wing design, but later on realised that wasn't feasible and switched to a delta configuration like everyone else).

[Blumf]

Wonder how much of the US's XB-70, rather than Concord, was in the Tu-144

[buzby]

Probably the biggest argument against it being a direct copy is that the Soviets didn't need to copy -  the Tu-144 wasn't particularly innovative, and didn't feature anything Russia hadn't built before.

The Soviets hadn't built any large supersonic aircraft prior to the Tu-144 (and Sukhoi T-4 - see below). The closest they had come was the Tupolev Tu-22 medium bomber (developed in response to the US B-58 Hustler), the prototype of which first flew in 1959 and it entered service in 1962. It was unreliable, dangerous to fly, underpowered and a massive disappointment as a bomber. It's poor aerodynamics meant could only just go supersonic and with the penalty of much-reduced combat range.

Tupolev completely redesigned the aircraft in the mid-60s (after starting the Tu-144 project) in order to keep their hand in with bombers (having lost out to Sukhoi on the XB-70 clone project) andit emerged in 1969 as the much more successful Tu-22M, now featuring swing wings (as was the fashion at the time).

Wonder how much of the US's XB-70, rather than Concord, was in the Tu-144

When the US were trying to develop an SST, North American developed the XB-70 into the NAC-60, but they lost out to Boeing and Lockheed in the contract for further development, which seems bizarre given they already had built something of a similar scale with the required performance (Boeing had no supersonic experience - Lockheed had the F-104 and A-12/SR-71 under it's belt)

The Soviet 'mirror' project to the XB-70 was the Sukhoi T-4, though development of it was started 3 years after the US programme started (and also after the development of Concorde had started), but it didn't fly until 3 years after the XB-70 programme was cancelled and Concorde's first flight.

Tupolev also had a competing design for XB-70-alike programme, and it's highly likely this is what was branched off into the Tu-144. The project for a Soviet SST was announced in 1962, 3 years after BAC had settled Concorde's design (based on the Bristol Type 198/Type 233 proposals) and started casting round for partners to share in the costs to develop and build it. The Tupolev design was selected in July 1963, around the same time as the design bureaux were entering their proposals for the XB-70 clone programme.

The Tupolev design for the XB-70 clone project would continue to be worked on after it was rejected/morphed into the Tu-144, and when the US later announced the B-1 project in 1970 (as a result of killing off the XB-70 in favour of strategic bombers capable of supersonic low-level penetration attacks) the Soviets responded with their own supersonic strategic bomber programme in 1972, which was won by Tupolev with the Tu-160 (developed from the Tu-144 by changing the double-delta wing to a blended-wing fuselage and variable sweep outer wings, both copied from the B-1A). It first flew in 1981 and entered service in 1987.

When NASA financed the reactivation of a Tu-144 for research purposes in the late 90s, it was re-engined with the Kuznetsov NK-32 engines developed for the Tu-160.

The concept of the drooping nose used on Concorde (and copied on the Tu-144) was first developed for the Fairey Delta 2 supersonic delta-wing research aircraft, which first flew in 1954 (and held the world airspeed record for a year in 1956), long before the XB-70. Previous experience with delta wing aircraft showed that high angles of attack were required on landing to maintain lift at speeds slow enough for a safe landing on normal-length runways, so the nose was designed to droop to allow the pilot better visibility in that situation.

The data from the FD2 programme contributed a lot to the design of the Bristol Types 188 and 233, and in 1961 it was rebuilt at Bristol's factory in Filton as the BAC221 to prove the high-speed performance of the  'Ogee' wing design that had been developed for Concorde.

[Glebe]

Thanks, was just a routine one to keep tabs on my MS, and there's nothing like a visit to a neurology ward to reinforce how massively fortunate I am relative to some. I'm fine!

👍👍👍👍

[lauraxsynthesis]

The new episode of True Anon is about this and as usual they're being very entertaining as well as informative. I'm about halfway through and Brace has asked who should be hung. Lots of responsibility being laid at the feet of McKinsey asset-stripping strategies.
https://soundcloud.com/trueanonpod/boeing-boeing-bong

[Senior Baiano]

Hope they provide the usual helpline numbers for stories about suicide lol

[bgmnts]

Unsure if this has been brought up in the thread, but this recent scrutiny of Boeing's lethal shoddiness has made me wonder about the disappearance of the MH370 and the hypoxia theory.

If there was a gradual decompression - like with the Helios 522 flight - it would be a fault with Boeing no? I'm sure they'll never ever know what happened but I reckon a lot of people are due a LOT of compo from Boeing at this point.

[buzby]

If there was a gradual decompression - like with the Helios 522 flight - it would be a fault with Boeing no? I'm sure they'll never ever know what happened but I reckon a lot of people are due a LOT of compo from Boeing at this point.

Not necessarily - the gradual decompression on the Helios flight was the crew's fault for not following the standard procedure and checking that the Cabin Pressure Controller was set to AUTO (it had been set to MANUAL after the previous flight following a pressurisatino check on the ground as part of a leak ckeck for one of the rear door seals), and the nnot recognising the cabin altitude warning, and stopping their climb. There have been a non-negligible number of CPC failures on the 737 leading to rapid decompressions, but the Helios incident wasn't one of them.

They would at least need the FDR and CVR of MH370 to find out what happened to it before the victims' families get lawyered uo.

[Dex Sawash]

I always have known that airbus noise was the cabin pressure gubbins sealing us all in and/or pumping us up. 
Mark your calendars with a quite rare dexwrong

[touchingcloth]

I always have known that airbus noise was the cabin pressure gubbins sealing us all in and/or pumping us up. 
Mark your calendars with a quite rare dexwrong

It doesn't feel right that it's the hydraulics pressurising, does it? First that that system would make a weird squeaky sound (hydraulic fluid leaking out?!), and second that it's needed at all - my car has hydraulic arms that keep the boot* open, but they don't need to be pumped up every time I take the car out. I can see why it makes sense to check that the pressure hasn't dropped before taking off, but the fact that every time I've ever been on an Airbus I've heard that sound for an extended period before taxiing seems odd.

*In the US of States you call this the "back bonnet", I think.

[buzby]

It doesn't feel right that it's the hydraulics pressurising, does it? First that that system would make a weird squeaky sound (hydraulic fluid leaking out?!), and second that it's needed at all - my car has hydraulic arms that keep the boot* open, but they don't need to be pumped up every time I take the car out. I can see why it makes sense to check that the pressure hasn't dropped before taking off, but the fact that every time I've ever been on an Airbus I've heard that sound for an extended period before taxiing seems odd.

The struts on your boot use pressurised gas, not oil. The gas does leak out over time (as Dex can no doubt attest).

Hydraulic systems operate at pressures of thousands of psi (the Airbus systems run at 3000psi). The systems have accumulators/reservoirs (tanks where excess fluid volume is kept). The reservoirs are kept pressurised by high pressure bleed air from the engines (to stop any gases dissolved in the fluid from precipitating out which could then lead to cavitation which would the pumps), so when the engines are turned off the pressure in the reservoirs will drop and the pressure in the rest of the system will then drop as it drains back to the reservoirs.

When the engines are restarted, the reservoirs will get pressurised by bleed air, but the system will still be at nowhere near the 3000psi pressure required to operate, so the engine-driven pump on the Green system is engaged run to pressurise that, and once that comes up to pressure the PTU then cuts they Yellow system to pressurise the Yellow system.

The noise the PTU makes is basically the same as the screeching noise the hydraulic rams on a digger or skip wagon make when they move, except it's contained inside a confined space.

[Ambient Sheep]

The gradual decompression on the Helios flight was the crew's fault for not following the standard procedure and checking that the Cabin Pressure Controller was set to AUTO (it had been set to MANUAL after the previous flight following a pressurisation check on the ground as part of a leak check for one of the rear door seals), and then not recognising the cabin altitude warning...

It didn't help that, if I remember correctly, the same horn noise was used for both the highly important cabin altitude warning and something rather more commonplace (flaps config?).

They just assumed it was the latter.

[Dex Sawash]

*In the US of States you call this the "back bonnet", I think.

Aux gun storage

[touchingcloth]

I met an American called Buck Bonét III once.

[buzby]

It didn't help that, if I remember correctly, the same horn noise was used for both the highly important cabin altitude warning and something rather more commonplace (flaps config?).

They just assumed it was the latter.

Yes, the Captain mis-identified the cabin altitude warning horn for the takeoff configuration warning. However, they had 3 opportunities to confirm the the CPC was to AUTO before then - the Preflight checklist, the Before Start checklist and the After Takeoff checklist. In the investigation it was found that the co-pilot had a history of rushing checklists and skipping items in his sim and line checks, and the Captain was an old-school German who wasn't a fan of CRM and 'commanded' his co-pilots (some of whom, including the one on the flight, had complained about him to the management).

The co-pilot also had an undiagnosed cardiac artery obstruction, which would have made him more susceptible to early-onset hypoxia. After the horn sounded as the aircraft passed 12000ft, the Captain contacted the company maintenance base on the radio to ask why the equipment cooling fan indicators were off (which is their normal state) and wanting to know where the circuit breakers were, which devolved into a rambling one-sided argument.

The engineer recognised what might be going on (as he had performed the pressurisation test the night before) and asked the Captain to confirm that the CPCs were both set to AUTO, but he kept rambling on about the circuit breakers until radio contact was lost.

During the conversation, the passenger oxygen masks deployed (which happens at 14000ft cabin altitude, which on the flight was as it reached 17000ft) with the accompanying indication and the Master Caution, but both the flight deck crew were too far gone to do recognise the situation or do anything about it by then.

[touchingcloth]

Helios

both the flight deck crew were too far gone to do recognise the situation or do anything about it by then.

I just yesterday watched an episode where a character was off his tits on opioids, couldn't understand what was going on on the radio, and so switched the power to the device off before a colleague got back to the station and took a while to identify that the switch was set to OFF.

https://for-all-mankind.fandom.com/wiki/Helios_Aerospace

[Captain Z]

I thought Helios was in charge of EasyJet, not Boeing.

[touchingcloth]

Fucking hell.
























(Laughed, tho.)

[Blumf]

Take the money and run!

https://boeing.mediaroom.com/2024-03-25-Boeing-Announces-Board-and-Management-Changes

ARLINGTON, Va., March 25, 2024  /PRNewswire/ -- Boeing [NYSE: BA] President and CEO Dave Calhoun today announced his decision to step down as CEO at the end of 2024, and he will continue to lead Boeing through the year to complete the critical work underway to stabilize and position the company for the future.

Board Chair Larry Kellner has informed the board that he does not intend to stand for re-election at the upcoming Annual Shareholder meeting. The board has elected Steve Mollenkopf to succeed Kellner as independent board chair.  In this role, Mollenkopf will lead the board's process of selecting Boeing's next CEO.

In addition to these changes, Stan Deal, Boeing Commercial Airplanes President and CEO, will retire from the company and Stephanie Pope has been appointed to lead BCA, effective today.

[buzby]

Edit: Blumf beat me to it.
I think Stan Deal's immediate 'retirement' was more an offer to fall on his sword. Making him carry the can for Boeing Commercial Aircraft's current predicament isn't going to change anything though without the whole corporate culture of the company changing dramatically.

Stephanie Pope is widely tipped to become the next CEO, so if correct she won't be in the BCA role long.

I wonder if there have been any more stock buybacks recently...

[Theoretical Dentist]

A second plane has had a part drop off.

[C_Larence]

[BlodwynPig]

"Passengers were transported to another aircraft"

Nawww, no way, how much is a taxi to New York?

[buzby]

A second plane has had a part drop off.

The aircraft was an older 737-800NG, built in 2015 (SouthWest was basically the model for RyanAir, with a fleet consisting entirely of 737NG and 737MAX variants). There have been a number of 737NG fan cowl door loss events over the years, but it's usually attributable to prior maintenance not latching and locking the doors properly prior to the aircraft going back into service (and the pilots then not noticing during their walkaround).

The A320 family did have a design flaw with the latches on it's fan cowl doors that made it hard to identify if they were fully locked, which led to a relatively large number of incidents of them opening in flight after maintenance had been performed. Airbus eventually changed the design in 2012, but it still happens occasionally.

The SouthWest incident in Denver is remarkable because of the landing speed. The crew could not use the flaps and slats in case they had been damaged by the departing cowling, so had to perform a high speed flapless landing. This was exacerbated further by the aircraft being at maximum weight just after takeoff and the 5500ft altitude at Denver (thinner air offers less resistance), all of which combined put the touchdown speed at approximately 210 knots, which is 20 knots over the maximum speed rating of the tyres and will have required all the runway (and all of the brakes) to slow down (if the flaps were available, the touchdown speed with max flaps would have been 130-140 knots). They did use the thrust reversers to help slow it down on the rollout, which is what caused the cowl doors to disintegrate after touchdown.

[BlodwynPig]

Its a hellish airport, Denver.

[Blumf]

Its a hellish airport, Denver.

[touchingcloth]

Haha.



Flaps.