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Another 737 MAX down.

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Curious four other snags on same tail during a span of seven days in December:


1. Capt. Side altimeter indication erratically showed a descent and a lower level and back to normal indication at FL380.

2. During approach @ 1000' AGL the A/C starts rolling to the right with the autopilot engaged.

3. During approach at 8600 feet, altimeter rapidly descended and returned to normal causing autopilot to revert to CWS "P", L-NAV remained engaged.

4. After take-off, altitude and vertical speed indicator on both PFD's showed an erratic and exaggerated indications (moving up and down very rapidly) for about 2 sec. and then returned back to normal.

The report states that maintenance action was performed and no reoccurance of same faults.  Maintenance action consisted of BITE checks with no faults founds and thereafter ground-tested serviceable. 

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Got to love “Ground Tested Serviceable”. 

I think a thorough review is required of the parts suppliers and overhaul shops who deal with the Boeing Max and these airlines. Apparently both AOA vanes on the Lion Air and Ethiopian aircraft were refurbished by the same Florida company (Xtra Aerospace) with some 85 reports of similar failures from current Max operators on components overhauled by them.

Edited by blues deville

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"That tells me that the software monster called artificial intelligence took control of the plane from its own pilots, and the pilots had to fight this monster again and again as the software pushed the nose of the plane down and they lost the fight,"  - Ralph Nader

Ralph Nader loses grandniece in Ethiopian MAX crash

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Boeing will slow 737 production by one-fifth; no layoffs planned

Seattle Times

April 5, 2019 at 1:06 pm Updated April 5, 2019 at 5:55 pm


Dominic Gates

Seattle Times aerospace reporter

The two recent fatal crashes and subsequent grounding of Boeing’s 737 MAX have prompted the jet maker to sharply and quickly cut production in Renton from the current 52 airplanes per month to 42 per month, signaling that a return to flight isn’t expected soon.

Boeing said it does not plan any layoffs due to the rate reduction, which begins in about 10 days. Managers are informing employees of the Renton 737 factory at meetings on Friday.

“The 737 program will maintain current employment levels,” said Boeing spokesman Paul Bergman. “We’re adjusting the rate to accommodate the pause in deliveries. There’s no employment impact.”

Boeing Chief Executive Dennis Muilenburg said the rate reduction will allow the company “to prioritize additional resources to focus on software certification and returning the MAX to flight.”

The move will hurt Boeing’s cash flow this year, putting more pressure on the share price, which has dropped 9 percent since the second crash, Ethiopian Airlines Flight 302 on March 10. Boeing announced the news of the production-rate drop moments after the stock market closed Friday.

About 12,000 people work at the Renton plant where the 737s are assembled. The plant now mostly produces the MAX model, with a fast-dwindling number of older-model 737s rolling off the line. In February, Boeing delivered 20 MAXs and just 14 older models.

Boeing makes rate-change decisions like this only reluctantly, because the impact on suppliers is severe and the whole production system will be disrupted unless all the suppliers can act in unison.

So Boeing typically changes the rate only when it knows it can maintain the new production pace for at least a year or so. In this case, Boeing is calling the rate reduction “temporary,” its extent dependent on how long the MAXs are grounded — which is unpredictable.

However, the move suggests Boeing anticipates a prolonged grounding lasting months. Obstacles to resumption of flight include both technical fixes and regulatory approvals from a global community of aviation-safety agencies that have grown more skeptical of both Boeing and the U.S. Federal Aviation Administration (FAA).

The 737 production system is such a well-oiled, efficient machine — it has gradually accelerated production from 27 jets per month 20 years ago to 52 per month today — that it can accelerate or slow down only in very carefully choreographed phases.


FAA official tells senator that Boeing 737 MAX inspectors were ‘fully qualified’

Every rate increase requires a synchronized step up by the entire supply chain, whether it’s a company supplying tens of thousands of small fasteners or one delivering dozens of whole fuselages.

It has to be meticulously planned so that raw materials and labor are in place to handle the extra work. Each step up means more money coming in, which is part of each supplier’s business plan many months ahead.

This rate decrease will require suppliers to correspondingly step down, meaning a hit to their business as well as potential layoffs.

Muilenburg said Boeing will “work directly with our suppliers on their production plans to minimize operational disruption and financial impact of the production rate change.”

Hardest hit will be Spirit AeroSystems in Wichita, Kansas, which makes the complete fuselages for all 737s and sends them by train to Renton. Spirit must quickly adjust its own pace to build 10 fewer fuselages per month.

Likewise, CFM International, which provides the new LEAP engine on the MAX, will have to deliver 20 fewer engines per month. But since CFM was struggling with the steep production ramp up of these engines, which are delivered to both Boeing and Airbus, the slowing of its pace may actually be a welcome chance to get back on track.

Bergman, the Boeing spokesman, said that because of the complexity of the 737 supply chain, once the grounding is lifted, production in Renton will have to ramp back up “in a phased approach.” That could mean some months.

It’s likely that once Boeing does get the go-ahead from the FAA and foreign regulators to begin flying the planes again, it will first ramp up to 47 jets a month and get that pace running smoothly before moving back up to 52 per month.

And when it does resume deliveries of the MAX, it will take Boeing many months to catch up on the delayed deliveries to airlines. It may shuffle the delivery schedule to try to accommodate airlines that need their planes sooner, asking others to wait longer.

Moving around the delivery schedule should be made easier because some airlines are now wavering on whether to defer or even keep their orders for the MAX. Some will want to hold off taking their airplanes until a successful re-entry into service has overcome anxiety among the flying public about the plane’s safety.

A resumption of higher production will depend on how long it takes to get approval from the FAA and foreign regulators for Boeing’s proposed software fix to the MAX’s flight-control system and accompanying pilot training.

 “We’ll have to monitor as we go,” Bergman said.

Other issues will also need addressed before the grounding can be lifted.

The preliminary investigation into the Ethiopian Airlines crash last month revealed that it had essentially the same cause as the Lion Air crash in October: a failed angle-of-attack sensor that measures the angle between the wing and the oncoming airflow fooled the flight computer into thinking the plane was pitched too high and triggered a new automatic flight-control system that pushed the nose of the jet down repeatedly.

But the sensors in the two accidents apparently failed in different ways. So in addition to the software update for its new Maneuvering Characteristics Augmentation System, or MCAS, Boeing will also have to find out how those sensors failed.

Airlines must also be satisfied before the MAX can fly again.

In an interview Thursday on NPR’s “All Things Considered,” Ethiopian Airlines Chief Executive Tewolde GebreMariam said he’s undecided on whether the carrier will stick with its Boeing order for 29 MAX airplanes.

“Boeing and the FAA will have to convince us all, not only Ethiopian Airlines, but all the regulators, all the operators that have grounded the airplanes,” Tewolde said. “We will have to be convinced beyond reasonable doubt that the airplane is safe to be back on the air and then we will decide what to do with our orders.”

CEO Muilenburg said Boeing is “coordinating closely with our customers as we work through plans to mitigate the impact” of the production cut.

In a note to clients last month, Ron Epstein, an aerospace-industry analyst with Bank of America, estimated a three- to six-month grounding is likely.

The 737s that continue to be built will still have to be parked all around the Puget Sound region until the grounding is lifted and deliveries resume.

The news of the sharp rate reduction seems to place out of reach Boeing’s publicly stated goal of increasing 737 production later this year to 57 jets per month.

That will have a competitive impact because Airbus is ramping up to build 60 single-aisle jets per month by mid year, including its rival A320 family of jets and its new A220 models. It has ambitions to hike that to 63 per month in subsequent years.

The higher rate allows Airbus to offer airlines earlier delivery slots. The main barrier to increasing its production has been the availability of LEAP engines, so the slowdown in supplying those engines to Boeing may even help Airbus ramp up more quickly.

On Friday, Bergman said he has “no information” about any change to the plan to ramp up to 57 per month. But Boeing cannot really plan for that without more clarity on when the grounding might be lifted.

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On 4/6/2019 at 8:45 PM, Rich Pulman said:

We’ve often kicked the can around this forum about what it means to be an “experienced” pilot and many have offered an opinion. In my opinion, experience is about more than knowing which buttons to push and where to point the nose. It’s more about instinctively knowing whether the information  your brain is receiving is correct or incorrect and then how to respond, or not. A non-experienced pilot might respond to a 74.5° AOA by lowering the nose, while an experienced pilot would instinctively reject that AOA as an impossibility and seek an alternative source of information.

What angers me most about what I’ve read so far is not that the MCAS system takes it data from a single source (although that’s bad enough), but that the smarty pants engineers at Boeing designed a system that would respond to what was clearly erroneous data. Seriously, can anyone here think of any possible scenario whereby a commercial airliner could physically achieve a 74.5° AOA while still being intact?

Designing a system such as the MCAS with a single data source is inexcusable. Designing it to respond to parameters that are physically impossible to achieve is criminal.


I believe they call that the Cobra Maneuver.  Pretty much limited to F22s and the like.


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3 hours ago, boestar said:

I believe they call that the Cobra Maneuver.  Pretty much limited to F22s and the like.


Did one in a T-33, but inadvertently, and ended up in a low level tumble...4310.gif.. (Student was doing a vertical roll and got confused..I think I already posted the story a long time ago)

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From AW&ST;

 April 12, 2019

LOS ANGELES—As the investigation continues into the causes of the Mar. 10 Ethiopian Airlines Boeing 737 MAX accident, sources close to the probe say flight data recorder (FDR) data firmly supports the supposition that the aircraft’s left angle-of-attack (AOA) sensor vane detached seconds after take-off and that, contrary to statements from the airline, suggests the crew did not follow all the steps for the correct procedure for a runaway stabilizer.

Detailed analysis of the FDR trace data shows that approximately six seconds after liftoff was signaled by the weight-on-wheels switch data, the data indicate the divergence in angle-of-attack (AOA) and the onset of the captain’s stick-shaker, or stall warning. Almost simultaneously, data shows the AOA sensor vane pivoted to an extreme nose-high position.

This, says one source, is a clear indication that the AOA’s external vane was sheared off—most likely by a bird impact. The vane is counter-balanced by a weight located inside the AOA sensor mounting unit, and without aerodynamic forces acting on the vane, the counterweight drops down. The AOA sensor, however, interpreted the position of the alpha vane balance as being at an extreme nose-high angle-of-attack.

With the stick shaker active, the trace indicates the crew pushed forward on the column to counteract what they believed were indications of potential approach to stall. The aircraft, now in level flight, also accelerated rapidly as its power setting remained at 94% N1 thrust used for take-off. This was followed by some manual trim inputs using the thumb switches on the control column.

Seconds after speed advisories were heard, the crew raised the flaps. With the autopilot turned off, flaps up and erroneous AOA data being fed to the flight control computer (FCC), the stage was set for the MAX’s maneuvering characteristics augmentation system (MCAS) to activate. This is indicated by approximately 8-sec of nose-down stabilizer movement, which was followed by the use of manual trim on the control column. However, with the MCAS having moved the stabilizer trim by 2.5 units, the amount of manual nose-up trim using the control column switches applied to counteract the movement was around 0.5 units, or roughly only 20% of the amount required to correctly re-trim the aircraft.

Because of the way the aircraft’s flight control computer P11.1 software worked, the use of manual trim using the control column switches also reset the MCAS timer, and 5 sec. later, its logic having not sensed any correction to an appropriate AOA, the MCAS activated again. The second input was enough to put in the full nose-down trim amount. The crew again manually counteracted with nose-up trim using the control column switches, this time offsetting the full amount of mis-trim applied by the latest MCAS activation.

By then, some 80% of the initial MCAS-applied nose down trim was still in place, leaving the aircraft incorrectly trimmed. The crew then activated the stabilizer trim cutoff switches, a fact the flight data recorder indicates by showing that, despite the MCAS issuing a further command, there was no corresponding stabilizer motion. The aircraft was flying at about 2,000 ft. above ground level, and climbing.

The crew apparently attempted to manually trim the aircraft, using the center-console mounted control trim wheels, but could not. The cut-out switches were then turned back on, and manual trim using the control column switches briefly applied twice in quick succession. This reset the MCAS and resulted in the triggering of a third nose-down trim activation lasting around 6 sec.

The source says the residual forces from the mis-trim would be locked into the control system when the stabilizer cut-off switches were thrown. This would have resulted in column forces of up to around 50 lb. when the system was switched back on.

Although this could have been reduced by manually trimming the aircraft using the center-console mounted control trim wheels, this did not occur, and the third MCAS activation placed the aircraft in a steep nose-down attitude. This occurred with the aircraft near its peak altitude on the flight—about 6,000 ft. The engines remained at full take-off power throughout the flight, imposing high aerodynamic loads on the elevators as the crew attempted to pull back on the columns.   

Vertical acceleration data also indicates momentary negative g during which the AOA sensor on the left side unwinds. This is seen as further validation of the theory that the external part of the alpha vane was detached as the apparent change in angle indication could only be explained by the effect of negative g on the counterbalance weight, forcing it to float up inside the sensor housing. In addition, the captain’s stick shaker also comes off twice in this final phase, further reinforcing the severed vane notion.

The source indicates the crew appeared to be overwhelmed and, in a high workload environment, may not have followed the recommended procedures for re-trimming. Boeing’s stabilizer runaway checklist’s second step directs pilots to “control aircraft pitch attitude manually with control column and main electric trim as needed,” according to one U.S. airline’s manual reviewed by Aviation Week. If the runaway condition persists, the cut-out switches should be toggled, the checklist says.

Edited by Don Hudson

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23 minutes ago, Don Hudson said:

The crew apparently attempted to manually trim the aircraft, using the center-console mounted control trim wheels, but could not.


25 minutes ago, Don Hudson said:

Although this could have been reduced by manually trimming the aircraft, this did not occur,

These two statements have me confused.  

Could they, or couldn’t they, re trim the aircraft manually?  

Or is the problem that they needed to unload the elevator first and did not know that?

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The terms “manual trim” have been sources of confusion and Boeing’s FCOM hasn’t made it clearer. For the AW&ST article, when referring to trim, the author accompanies the term, "manual" with a description of which manual trim is being used, the control column switches or the center console trim wheels.

Take a look at the AW&ST article, re-posted with descriptions of which "manual" trim is in use, (red font).

The term "manual trim" is used in five places in which "switches" or "wheel" are not specified, and one place in which the Boeing’ runaway stabilizer checklist is referenced as, “control aircraft pitch attitude manually with control column and main electric trim as needed,”. “Main electric” would of course be the control column switches. I used red font in the original article below, clarifying what “manual trim” is being referenced. Apologies if it seems a bit pedantic. It was the only way I could get it clear in my own mind... ?

So, yes, they could trim the aircraft manually using the control column switches until they used the cut-off switches.

Why they couldn't use the manual trim wheels on the center console has not been determined, but one reason may be the rate at which these wheels change the revolution is about 0.07deg of HS trim, or, 1deg change using the wheels takes almost 15 turns.*

Also, from what I have read, it's easier to rapidly turn the wheel, (handle extended), from the left seat than the right. This may have to do with simply being right or left handed.

And yes, they could have used the manual (switches) trim right up to the end. This is verified by the albeit-tiny change, that the two manual-switch inputs by the crew changed the HS position.

Full HS range using manual trim wheel = 17deg

It takes 250 turns to go from stop to stop.


Edited by Don Hudson

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@Don Hudson,

It's the bits that are not said, that lead to confusion.

Boeing's FCOM Bulletin states that "Electric stabilizer trim can be used to neutralize control column pitch forces before moving the STAB TRIM CUTOUT switches to CUTOUT".

Missing; is it failed to WARN that the electric trim MUST be used BEFORE using the CUTOUT switches, in order to NEUTRALIZE the back force on the control column. This effectively means that if the aircraft is not properly trimmed before activating the CUTOUT switches, manual trimming may be impossible.

My feeling is that the throttles were set for the projected climb, and the trim problem, UAS, stick shaker, warnings etc.. overwhelmed the crew, and eventually the increasing airspeed  resulted in HS 'blow-back' -  or HS stall.  That's when the final AND occurred.


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Hi Woody;

Minor point, the Boeing FCOM wording is from the FAA Emergency AD's issued November 07, 2018 and December 21, 2018 as a revision to the AFM, (Airplane Flight Manual).

It is obviously impossible to trim if the cut-off switches have been moved to CUT-OFF without trimming first, but the wording in the AD is to ensure neutral trim prior to doing so*. If I understand what you meant by, " manual trimming may be impossible ", I don't think trimming to neutral using the manual trim switches on the control column would be impossible purely due to high loads on the HS. Stabilizer 'blow-back' can occur with a "ball-screw" arrangement, (vice a screw-jack) but there are two brakes on the HS mechanism that are released whenever the electric trim or the manual-wheel trim is used. I believe that electric trim was available because there is slight HS movement concurrent with the last two blips of ANU electric trim, (resetting the MCAS which dutifully re-trims AND for ~6" resulting in the final dive).




* There is no statement in the AD or the FCOM requiring that the procedures (in Fig.2 & the Runaway Stabilizer NNC) set out/referenced in the FAA AD are to be executed by memory. The FAA and Boeing leave it to individual airlines and crews to decide how to handle these procedures.

Runaway stabilizer NNC:



FAA AD revision:

* i-2F8Dppn-M.jpg



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3 hours ago, Don Hudson said:

I don't think trimming to neutral using the manual trim switches on the control column would be impossible purely due to high loads on the HS.

Don, The trim switches on the CC are electric. The only way to trim manually is with the cut-out switches OFF and moving the stab trim wheel manually.

I think WOODY was referring to the idea that if the Cut-OUT switches are  turned off in a High Speed ND attitude (Not electrically trimming to a  neutral attitude first), the manual effort of moving the manual trim wheel may be exceedingly difficult to achieve.

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Hi Kip;

Yep, got that, thanks.

As I expressed in my previous post to Turbofan, “Main electric” would of course be the control column switches."

But that illustrates why I wrote the full descriptions in red font in the original post of the article from AW&ST - the article uses the term "manual" when referring to the trim wheels but conflates the term "manual" when applied to the trim switches on the control column because they're manipulated by hand even as they are controlling an electrically-driven, (primary) trim system.

edited to add: There is further confusion regarding manual & electric trim - it is claimed, (but without verifiable evidence yet) that the manual trim wheels could not be moved. One theory is, "HS stall due high loads on the trim mechanism due high airspeed". But the trim moved ANU when the crew used the CC trim switches, (indicating, along with MCAS input, that the cut-off switches had been moved back to their normal position). Manual trim using the wheels doesn't work but electric does? Why?

On Woody's comment, yes, got that too but probably didn't express it very well.

It makes complete/logical sense that if the trim has run away due MCAS and nothing was done until time had passed, then when the trim is cut off by the CUTOFF switches, it freezes the system with whatever trim was in prior to using the switches. That's why the NNC states to trim neutral then cut-off the trim, (but, and Woody makes this point), the FAA AD doesn't emphasize the highly-critical importance of trimming the pitch to neutral right away and then cutting off the trim system. That's the key of course, and I agree with Woody that the wording is weak and buried, but it isn't confusing - it's just obscured in all the blather of the FAA's original and subsequent ADs.

This goes back to the absence of any information and therefore training for a system that controls the most powerful flight control on the aircraft which has the potential for loss of the aircraft under certain, previously-latent conditions.

Edited by Don Hudson

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I can't recall the exact number of full rotations one has to do manually for the full range of trim available but for my  training experience I did fly an approach from 10000 feet to touchdown using just manual trim. The point here is that the max speed I had was 250 kts, backing off to final approach speed but I do recall that when gear and flaps were dumped it was rather awkward to get the correct trim on.

I would assume if these fellows went to manual trim, ND, with the speed increasing and in that case it would be difficult to trim out to neutral due to the increasing air load on the HS.and if they felt that manual trim was not working, perhaps that is the reason for selecting STAB TRIM back on.

Bear in mind, I was flying the T-Rex, (200), when the earth was cooling and best I can get out of the mental file cabinet was  40-45 turns to go from full ND to full NU.

Edited after Internet search....?Well there is certainly a load full of opinions out there as to how many revolutions the manual trim wheel has from max ND to max NU and upon reflection of a fading memory, perhaps my "40 revolutions" was what I used during my flight. The exact number , according to numerous sources is somewhere between  65 -235 revolutions....If you are associated with the 800 MAX, have strong arms, and wrists, how about going into one of the non flying machines and spinning the wheel from max NU to max  ND and report back here...Perhaps your name/avatar will be go viral in all aviation related forums....PS...Make sure you put the trim back where you found it before you leave the aircraft  ?

Edited by Kip Powick
additional info

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4 hours ago, Kip Powick said:

and if they felt that manual trim was not working, perhaps that is the reason for selecting STAB TRIM back on.

Yes, I think that's a reasonable notion.

On turns of the wheel, I've read that it takes 250 turns to go from full NU to full ND, (17°), or 14.7 turns for one degree or 0.068° per turn. That is not verified in any manual to which I have access, but if it's that, one can understanding giving the method up and turning the system back on again.

If it's 40-45 turns for 17°, then its just over a third-of-a-degree per turn. I suspect the mechanical advantage, (ratio of 1 turn to how much the stab moves) would be small and the wheel would be very difficult to move.

As shown in the traces with the last two blips of trim, the Pitch Trim parameter moves so the CC trim switches worked, which I believe is evidence that the manual method would have worked but not fast and probably not easily. - they had a long way to wind the trim ANU at ~15 turns per degree.

I don't know how units and degrees relate - and I could be using "degrees" when it might be "units". Again, there is no information in the AMM, the AOM or the FCTM.

Edited by Don Hudson

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2 hours ago, Don Hudson said:

Again, there is no information in the AMM, the AOM or the FCTM.

And that’s not really acceptable, IMO.  Why isn’t that information in those manuals?

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9 hours ago, conehead said:

And that’s not really acceptable, IMO.  Why isn’t that information in those manuals?

Gosh, I don't know what's acceptable anymore conehead. We are in a period of great flux. As my brother, an electrical engineer, says with a smile, "That's the wonderful thing about standards: there are so many to choose from."

To me anyway, the Boeing manuals I have experience with are thin on information. The details of what a control or indicator actually does and how it works are absent. I think there is less than even pilot-NTK information but that's just my view. I know the reasons, one of which Boeing itself stated recently with regard to MCAS.

So, for the 250 turns, I have two was a PPRuNe post on the Ethiopian thread, and the other was a site where someone was building their own flight-simulator and made the statement regarding "250 turns". Kip's mental filing cabinet may very well be functioning perfectly!

One way or another, people will find things out, fill stuff in or, these days it seems to me, with increasing legitimacy, just make up the information they want or need.

It's always best that original, formal sources, (the manufacturers, the regulator, etc.), share as much as they can when working in high-risk enterprises. Otherwise, trust in information, (and resulting behaviours) become an issue as we "choose" our standard then claim we've met it.

Not a good way to do aviation, in my opinion.

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Seattle Times

With close industry ties, FAA safety chief pushed more delegation of oversight to Boeing

April 14, 2019 at 6:00 am
Dominic Gates

By Dominic Gates

Seattle Times aerospace reporter

In 2012 the Department of Transportation’s Inspector General sent investigators to interview Federal Aviation Administration (FAA) technical staff in Renton, where engineers working under manager Ali Bahrami were responsible for certifying new planes developed by Boeing.

The investigation substantiated employee allegations that FAA managers did not always support efforts by their technical experts to ensure Boeing complied with safety rules. It found “a negative work environment” where safety engineers feared retaliation “for attempting to hold Boeing accountable.”

Now, two fatal crashes of Boeing’s 737 MAX have brought new scrutiny to the close-knit relations between the regulatory agency and the industry, to the FAA’s practice of delegating most safety analysis for new Boeing airliners to Boeing itself, and to shortfalls in the FAA’s final oversight role.

With the MAX crisis jolting public faith in both Boeing and the FAA, Bahrami, now the executive at FAA headquarters in Washington D.C. specifically tasked with ensuring aviation safety, faces the daunting task of restoring confidence in his agency and in the process of certifying aircraft as safe.

Hank Krakowski, former chief operating officer at the FAA, says, “Ali, coming from the certification branch in Seattle, is uniquely qualified to manage through this current situation.”

But Michael Collins, a just-retired aerospace safety engineer who worked under Bahrami here, sees him as representing what’s gone wrong at the FAA.

“He helped foster a culture among management in Seattle of delegating more than the FAA technical specialists were comfortable with,” said Collins. “When the FAA’s safety engineers had an opinion different from Boeing’s, he tended to side with Boeing.”


Personifying tight FAA/industry relations

Bahrami, 64, was born in Iran and came to the U.S for his education not long before Ayatollah Khomeini’s 1979 revolution.

That year, having already earned a B.S. degree in engineering, he completed his M.S. at the University of Michigan and like many educated Iranian exiles decided not to return to his newly theocratic homeland. Instead, he took a job as an engineer with Douglas Aircraft in southern California, where he spent 10  years.

Bahrami joined the FAA as an engineer in 1989, then rose to become in 2004 manager of the Transport Airplane Directorate in Renton, which oversees the safety of the operating fleet of U.S. commercial aircraft as well as the certification of new airplane models.

During his tenure in Renton, Bahrami spearheaded efforts to delegate more inspection and certification work to industry, and specifically to outsource much of the safety analysis of new Boeing jets to Boeing itself.

In 2013, Bahrami made a move reflecting the tightly intertwined relationship between regulator and industry.

Just months after overheated batteries in flight caused the worldwide grounding of Boeing’s recently introduced 787 Dreamliner — a jet that Bahrami had shepherded through certification — he left the FAA for a lucrative lobbying job as a vice president of the Aerospace Industries Association,representing the big U.S. aerospace companies.

That fall, testifying for the trade group before the House Subcommittee on Aviation, he painted the regulatory process as too slow and asked for changes to make it “more responsive to industry.”

“We urge the FAA to allow maximum use of delegation,” Bahrami told Congress, now wearing an industry hat. “It would be detrimental to our competitiveness if foreign manufacturers are able to move improved products into the marketplace more quickly.”

Then in 2017, he returned to the FAA executive ranks at just one level below the top job: Based at FAA headquarters, he’s now associate administrator for aviation safety, overseeing 7,200 employees and a budget of $1.3 billion.

Former National Transportation Safety Board (NTSB) chairman Jim Hall succinctly summed up his view of Bahrami: “He’s been the agent for Boeing’s self-certification.”

Bahrami, in emailed responses to questions, defended the delegation of safety analyses to Boeing and other private companies, and disputed Hall’s characterization.

“Delegation is not self certification,” he said. “Our staff remains engaged throughout the certification process.”

The U.S. aviation system, he insisted, “has never been safer.”

Boeing controls certification

Today’s reality is that when Boeing designs a new airplane, almost all the hands-on safety evaluations and tests are done by employees of Boeing or Boeing’s suppliers who are authorized to represent the FAA.

These Authorized Representatives (ARs) file written documents that are then evaluated for compliance and signed off by FAA technical specialists.

A Seattle Times investigation published last month showed that the safety analysis of a new flight control system on the 737 MAX that played a major role in the fatal crashes of a Lion Air jet last October and an Ethiopian Airlines jet last month was done entirely by Boeing.

In addition, FAA engineers complained of being asked to delegate even more of the work to Boeing than originally agreed and of a constant schedule pressure during MAX certification.

They said they were often given insufficient time to finish the evaluations — which in that case were sometimes signed off not by the technical staff but by managers or even just delegated back to Boeing for a final decision.

In the case of the MAX’s suspect flight control system — called Maneuvering Characteristics Augmentation System, or MCAS — as a result of flight testing in the final year of certification, Boeing made significant changes to how it worked, including in certain circumstances increasing by a factor of four the system’s authority to move the horizontal tail so as to push down the nose of the plane.

Those changes were never communicated back to the FAA technical staff, who had seen only a system safety analysis prepared before the changes.

Drawing on Boeing’s expertise

As the 2012 Inspector General (IG) investigation indicates, there was constant tension throughout Bahrami’s tenure as FAA boss in Renton between the agency’s technical staff, who wanted stringent application of the safety regulations, and managers who pressed for more speed and ever more delegation to Boeing.

Mike McRae, a former senior aerospace engineer at the local FAA office, retired in 2013, a month before Bahrami left for his four-year stint working for industry. McRae said he retired unhappy with the direction of the safety agency and management’s lack of support for technical staff.

He described Bahrami as a very capable bureaucrat who merely implemented the policy of increased delegation that was pushed from FAA headquarters. When Bahrami came in as boss, the policy was already firmly in place, mandated by Congress under heavy lobbying from Boeing and other giant aerospace companies.

“He was a product of that culture,” said McRae. “He was inclined to delegate more. He thought we had to get the companies to take more responsibility for safety.”

“That’s not irrational,” he said. “Delegation is an unfortunate necessity. You can’t fund an old-school regulatory FAA.”

But McRae added, “I personally think they took it too far.”

Bahrami himself argued, both from inside the FAA and when he spoke for industry, that there’s no alternative to delegation. The FAA has only about 1,300 personnel in its certification offices around the country, compared to the 56,000 engineers at Boeing.

At a 2013 NTSB hearing after the 787 was grounded due to overheating lithium-ion batteries, Bahrami testified that he had only 20 to 25 staff working on the jet’s certification, so the FAA had to rely on 950 Boeing ARs to oversee and approve the detailed work.

FAA personnel who certified the 787 never visited the battery manufacturer in Japan nor the company in France that designed the surrounding battery system. Boeing ARs handled all of that.

And two IG audits have turned up shortcomings in the broader delegation process.

An audit in 2011 found 45 instances between 2005 and 2008 where the agency had not carefully reviewed certification plans in advance, including one plan that didn’t comply with the regulations governing aircraft flight controls.

A 2015 audit revealed that the previous year the agency had performed direct oversight of only 4 percent of the ARs conducting certification work on behalf of the FAA at aerospace suppliers.

Bahrami co-chaired an extensive review of the airplane certification process in 2012. Tellingly, he was the only FAA representative on the review committee along with eight representatives of industry. The co-chair was Christine Thompson, a senior manager of Boeing’s airplane certification organization.

That review recommended that because “the FAA has limited capacity,” it should “maximize delegation to the greatest extent.”

A year later, now testifying for the industry, Bahrami told the House committee that due to lack of resources and budget the FAA simply cannot perform all the technical audits required to certify planes as safe.

“Expecting FAA to keep pace with industry … is not in the realm of possibilities,” he said.

Answering questions this month via email Bahrami said that this delegation of work to industry “enables regulators to leverage expertise at manufacturers’ facilities.”

He added that the shortage of engineers throughout the aviation industry means the public sector must compete with the private sector in attracting talent.

“Given the complex nature of today’s aviation products, it is virtually impossible for regulators to have all necessary expertise in every FAA office throughout the country, especially when global manufacturing models continue to evolve and grow,” Bahrami wrote.

Mo Yahyavi, a former top executive at Boeing who ran the 747-8 program while that big jet was being certified in 2010, said Bahrami came with his team and toured the Everett production line as the test planes were being built, to verify and validate Boeing’s work on the design and testing.

“I really was impressed with the guy as a hands-on person and trustful,” said Yahyavi.

Earlier in his career, Yahyavi was himself designated an FAA representative at Boeing specializing in propulsion systems, and was given extra training for that role in how to interpret and define how the jet’s software worked with its mechanical systems.

He said ARs at Boeing all have such specialized expertise. “There’s no way a certification organization like the FAA can understand and verify and validate everything by itself. They depend on the manufacturer’s engineers.”

“The system was working,” Yahyavi concluded. “I wouldn’t change anything.”

The gold standard of air safety

Until the MAX crashes, regulation of aviation safety in the U.S., where 2.6 million passengers fly every day, has been the model for every other country. The last commercial passenger airplane lost in a crash in U.S. airspace was 10 years ago.

In the decade since, airlines have flown 7.4 billion passengers safely to their destinations on 90 million U.S.-regulated flights with exactly one passenger death: on a Southwest Airlines 737 last year when an engine disintegration in flight blew out a window.

That’s a remarkable record, not even closely approached by any other form of transportation.

Former NTSB chair Hall believes the historically high level of air safety is based on years of experience and care, that’s now at risk from excessive delegation to industry.

He points to the Volkswagen emissions scandal as evidence that “greed drives industry to do things that do not benefit society.”

And he’s not impressed by Bahrami’s argument that the FAA doesn’t have the resources.

“I have a hard time understanding anyone who sells increased industry participation by essentially saying that the agency he represents is incapable of doing its job,” said Hall.

“Safety depends on checks and balances,” he added. “When you don’t have the checks in place, things get out of balance.”

In the wake of the two MAX crashes, Congress has been scrambling to hold hearings and demand accountability. The House Committee on Transportation and Infrastructure has requested records from Boeing and the FAA as part of its investigation into the 737 MAX certification process.

And yet Congress itself has backed that process, with prodding from the industry. The latest legislation, the FAA Reauthorization Act of 2018, passed into law just weeks before the Lion Air crash last October, requires the FAA to “delegate fully” unless the head of the agency determines there is specific public safety reason to limit the delegation.

In such a case, the FAA is instructed to work with the industry partner to return it to full authority. Furthermore, if any certification glitch occurs to slow down an airplane program, the FAA must automatically elevate the issue to management and resolve it within a time period agreed with the manufacturer.

Hall says the reason for such provisions is straightforward: The heavy lobbying of Congress by Boeing and other aerospace companies.

U.S. Transportation Secretary Elaine Chao, the ultimate boss of the FAA, is the wife of Republican Senate Majority Leader Mitch McConnell. But the influence is bipartisan. In the late 1990s, the deputy FAA administrator and for a time acting administrator was Linda Hall Daschle, wife of U.S. Senator Tom Daschle, then Democratic Senate Minority Leader. Linda Daschle left the FAA to work as an aerospace lobbyist.

Former FAA chief operating officer Krakowski defends the role of manufacturers in ensuring the safety of their own products. While there is always commercial pressure to meet schedules, he said, jet manufacturers face a more existential pressure to make their airplanes safe.

“If you don’t, the ramifications for Boeing and the airlines are evident right now” with the MAX crisis, he said. “I think there is a moral driver (to protect passengers) that Boeing does understand, but also, from a business point of view, the consequences they are living with right now are an additional driver.”

Yet somehow, this complex safety ecosystem failed on the MAX.

Krakowski said that the missed flaws in the MCAS flight control system that seem to have caused both recent crashes mean something went wrong not only at Boeing and the FAA, but also at the major airlines, where the flight technical departments “typically know every nut and bolt on the airplane and how it should operate.”

“All three own a piece of this. Nobody raised a hand and said, wait a minute, let’s talk more about this system,” he said. “I’m thunderstruck nobody caught this.”

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I just  manually  manipulated the trim (on the ground) from 0-15 units, min to max 250 turns. With no air load I ran out of steam less than halfway.

They had their hands full, literally.

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2 hours ago, thinair said:

I just  manually  manipulated the trim (on the ground) from 0-15 units, min to max 250 turns. With no air load I ran out of steam less than halfway.

They had their hands full, literally.

Sounds like a work out.

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