[johnm]

Why did the FAA not do this

and does the US president have the powers to order such a grounding?

It doesn't matter, if the President calls the FAA and “suggests “ grounding the 737 max it’d be a brave staffer who said no

Sadly it looks that the dear old 737 might have finally been overdeveloped......

[Dave W]

Sadly it looks that the dear old 737 might have finally been overdeveloped......

If ever there was a time to say "Should wait for the NTSB report", this might be it.

[Rob L]

Why did the FAA not do this

and does the US president have the powers to order such a grounding?

It doesn't matter, if the President calls the FAA and “suggests “ grounding the 737 max it’d be a brave staffer who said no .....

It may indeed not matter, @johnm, but it doesn't answer my question. Perhaps the US President does have that power, I don't know.

[Dave W]

Is simply disabling this particular & automatic anti-stall process even more dangerous ? Otherwise presumably Boeing would have done that weeks ago.

"We" don't (yet) know if the anti-stall function was/wasn't a factor in the second accident.

[Iceman]

As well as Boeing, I would imagine that there is a few worried people in the FAA tonight. If it transpires that the second accident was caused by the same problem as the first then the FAA will have to answer as to why they didn't ground the type as soon as they knew that a design problem caused the first accident.

Iceman

[GrahamB]

The FAA have fallen in line.

[Josh]

Sadly it looks that the dear old 737 might have finally been overdeveloped......

If ever there was a time to say "Should wait for the NTSB report", this might be it.

Just having flown the NG, and for reasons entirely unrelated to this or the Ethiopian accident I could happily tell you for the price of a beer that the 737 has been overdeveloped for a long time already.

[neilmurg]

"We" don't (yet) know if the anti-stall function was/wasn't a factor in the second accident.

Yes we don't know and shouldn't speculate.
But on a general point, the 737 does look like an airframe which is struggling to compete with the A320, specifically its short legs and therefore difficulty in accommodating an efficient high bypass ratio engine.
The desire to have it rated as an aircraft which does not require differences training adds another complication.
Trying to compete with Airbus fly-by-wire protections adds a further difficulty.

Until we know what caused this second tragedy the above is moot. It does seem sensible to pause Max-8 operation until there is a better understanding of the latest crash and whether it is related to the first one. It sounds like preliminary results may be imminent.

Hopefully aviation will learn from these events and we'll all be safer as a result, it's not Airbus or Boeing, it's a common sky, they learn from each other

[KeithM]

Why did the FAA not do this

and does the US president have the powers to order such a grounding?

It doesn't matter, if the President calls the FAA and “suggests “ grounding the 737 max it’d be a brave staffer who said no .....

It may indeed not matter, @johnm, but it doesn't answer my question. Perhaps the US President does have that power, I don't know.

I suspect that he might well have the power, if not legally, certainly politically.

In view of his “America First” and “Make America Great Again” slogans, I can imagine what the general nature of his conversations might have been with the FAA and/or Boeing.

And It could be that his intervention was also not totally lacking in political motive.

[MichaelP]

In my opinion, any aircraft that is expected to be able to be flown by a human being should have sufficient stability to not require a system such as the one fitted to the Max.

Yes, airliners have stick shakers to warn of a stall. These do not prevent stalls.
The Airbus has (from memory) five computers, and two different softwares. There’s no reliance on a single source computerised system.
Clearly as in the Air France accident an Airbus can be held in a stall (alternate law?).
But the natural stability of older designs meant that such a situation requires the direct input by the pilot.

The instability of the 737 Max series means that the aeroplane itself may depart from controlled flight under certain circumstances and since this is apparently easy, the aeroplane requires electronic means to take over.

I believe that any aeroplane carrying passengers, and able to be flown by a pilot should have a tendency to return to controlled flight when disturbed otherwise rather than having a fallible system to compensate.

So the airframe itself needs modification.
I see a suggestion that a larger tailplane should be fitted... Maybe this is a good idea?
But regardless, passenger planes should have proper stability built into them.
Engines need to be placed in positions that do not lead to a departure from stable flight under any circumstances.
Any change in engine position should have airframe-aerodynamic correction as necessary.

The short legged 737 had to have modifications to take the CFM56, larger engines should not be fitted if their position causes undesirable aerodynamic effects.

[Dave W]

Boeing Statement on 737 MAX Software Enhancement

March 11, 2019 - The Boeing Company is deeply saddened by the loss of Lion Air Flight 610, which has weighed heavily on the entire Boeing team, and we extend our heartfelt condolences and sympathies to the families and loved ones of those onboard.

Safety is a core value for everyone at Boeing and the safety of our airplanes, our customers’ passengers and their crews is always our top priority. The 737 MAX is a safe airplane that was designed, built and supported by our skilled employees who approach their work with the utmost integrity.

For the past several months and in the aftermath of Lion Air Flight 610, Boeing has been developing a flight control software enhancement for the 737 MAX, designed to make an already safe aircraft even safer. This includes updates to the Maneuvering Characteristics Augmentation System (MCAS) flight control law, pilot displays, operation manuals and crew training. The enhanced flight control law incorporates angle of attack (AOA) inputs, limits stabilizer trim commands in response to an erroneous angle of attack reading, and provides a limit to the stabilizer command in order to retain elevator authority.

Boeing has been working closely with the Federal Aviation Administration (FAA) on development, planning and certification of the software enhancement, and it will be deployed across the 737 MAX fleet in the coming weeks. The update also incorporates feedback received from our customers.

The FAA says it anticipates mandating this software enhancement with an Airworthiness Directive (AD) no later than April. We have worked with the FAA in development of this software enhancement.

It is important to note that the FAA is not mandating any further action at this time, and the required actions in AD2018-23.51 continue to be appropriate.

A pitch augmentation control law (MCAS) was implemented on the 737 MAX to improve aircraft handling characteristics and decrease pitch-up tendency at elevated angles of attack. It was put through flight testing as part of the certification process prior to the airplane entering service. MCAS does not control the airplane in normal flight; it improves the behavior of the airplane in a non-normal part of the operating envelope.

Boeing’s 737 MAX Flight Crew Operations Manual (FCOM) already outlines an existing procedure to safely handle the unlikely event of erroneous data coming from an angle of attack (AOA) sensor. The pilot will always be able to override the flight control law using electric trim or manual trim. In addition, it can be controlled through the use of the existing runaway stabilizer procedure as reinforced in the Operations Manual Bulletin (OMB) issued on Nov. 6, 2018.

Additionally, we would like to express our deepest condolences to those who lost loved ones on Ethiopian Airlines Flight 302. A Boeing technical team is at the crash site to provide technical assistance under the direction of the Ethiopia Accident Investigation Bureau and U.S. National Transportation Safety Board. It is still early in the investigation, as we seek to understand the cause of the accident.

[Bill McCarthy]

In my daily rag the other day - a “witness said that flames were seen coming from the back of the aircraft” as it went down. A querk of the mind in such circumstances perhaps.

[stevelup]

It's not impossible - the airflow into the engines may have been disturbed during the upset which could have caused surging.

An effect, not a cause.

[skydriller]

Boeing Statement on 737 MAX Software Enhancement
Boeing’s 737 MAX Flight Crew Operations Manual (FCOM) already outlines an existing procedure to safely handle the unlikely event of erroneous data coming from an angle of attack (AOA) sensor. The pilot will always be able to override the flight control law using electric trim or manual trim. In addition, it can be controlled through the use of the existing runaway stabilizer procedure as reinforced in the Operations Manual Bulletin (OMB) issued on Nov. 6, 2018.

As an aside, reading the above made me remember this:

Interestingly last night on National Geographic, they showed the XL Airlines A320 crash in the South of France on their Air Crash Investigations programme. It was determined that during an acceptance handling test, this accident was caused by the AOA sensors being frozen so that conflicting air data to the computers returned the aeroplane to Manual Mode when the crew expected the aeroplane to Auto-recover (the reason for their handling test). They eventually tried to manually recover by pushing forward, but the stabilizer trim was auto-adjusted fighting them (they were supposed to manually change this too) and they ran out of height.

Regards, SD..

Edit to make the quote thing work

[eltonioni]

Boeing's grounded the MAX .