B737 Max 800 Certified in the US

[Pilotman]

Well good luck to anyone who gets suckered into flying on this piece of  badly designed xxxx. They haven't solved the primary problem of this aircraft, in that , contrary to all civilian aircraft that I know of, or have ever heard of, it was designed knowing it to be  inherently unstable. All civilian passenger aircraft should be able to glide, engine and primary electrics unavailable, not well, but they can still do it.  The Max 800 cannot.  I will never fly on this aircraft, ever. I would rather walk. 

[CharlieH]

For those who wish to see the subject....courtesy of Google

 

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[dbrenn]

19 hours ago, Pilotman said:

Well good luck to anyone who gets suckered into flying on this piece of  badly designed xxxx. They haven't solved the primary problem of this aircraft, in that , contrary to all civilian aircraft that I know of, or have ever heard of, it was designed knowing it to be  inherently unstable. All civilian passenger aircraft should be able to glide, engine and primary electrics unavailable, not well, but they can still do it.  The Max 800 cannot.  I will never fly on this aircraft, ever. I would rather walk. 

It can't glide? Why not? 

[Pilotman]

2 hours ago, dbrenn said:

It can't glide? Why not? 

the centre of gravity is in front of the centre of pressure even when the speed increases and the CoP moves forward.  This is due almost entirely  to the weight of the new engines and the configuration of the new aerofoil shaping. Boeing fitted soft ware to over come this inherent design  fault. obviously not well enough.  

[Maybole]

This aircraft has been repeatedly developed to keep up with its Airbus rival which is 20 years younger. I remember Britannia Airways using them at Abbotsinch in 1968. A selling point was that it was low to the ground thus making maintainance and loading possible without special equipment. This has made installation of larger engines increasingly difficult resulting in centre of gravity problems. Also the airflow patterns over the wing have been altered making for problems in the effect of the control surfaces. In order to avoid an extensive (and expensive) redesign, which may make problems in airworthiness certification, Boeing have resorted to advanced electronics to prevent pilots from getting near the limits of the flight envelope.

 The design has gone beyond its development capabilities and should have been abandoned in favour of a competently new aircraft.

 

[NanLaew]

I understand that the EU's equivalent of the FAA have also given this aircraft the nod. This despite the software change they requested that were in addition to the FAA's requests not being fulfilled for maybe two more years.

[dbrenn]

On 12/12/2020 at 7:38 PM, Pilotman said:

the centre of gravity is in front of the centre of pressure even when the speed increases and the CoP moves forward.  This is due almost entirely  to the weight of the new engines and the configuration of the new aerofoil shaping. Boeing fitted soft ware to over come this inherent design  fault. obviously not well enough.  

The software was intended to make trim corrections under power, to compensate for the forward position of the engines raising the nose and causing a stall. With no power on, such as in a glide, why would the software be relevant? Surely during a descent, with engines at idle, it's gliding anyway?

[Pilotman]

6 hours ago, dbrenn said:

The software was intended to make trim corrections under power, to compensate for the forward position of the engines raising the nose and causing a stall. With no power on, such as in a glide, why would the software be relevant? Surely during a descent, with engines at idle, it's gliding anyway?

At idle in normal operations, say in landing. the new software is still required to keep the aircraft flying in stable configuration.  I have explained this earlier, with the CoG forward of the CoP it will not glide to the required degree, it would quickly become uncontrollable.  One report asked why the crashed aircraft could not be controlled even with the engines at idle and producing  minimum thrust; that is the reason. The aircraft is dangerously unstable unless corrected by software.  That is all very well for military aircraft, that need to be agile and highly manoeuvrable, but it is insanely irresponsible in a civil airliner.  Ask yourself why Boeing had to upgrade and change the software system, rather than remove it altogether ? The reason is obvious, the aircraft will not fly, cannot fly without it. Boeing need to be charged with culpable manslaughter for the deaths and someone, maybe quite a few of their people need to be in  jail. I like Boeings.  I have flown them and appreciated their engineering excellence,.  In this case, they made a grave error and they need to pay for it. But of course they will not. 

Edited December 14, 2020 by Pilotman

[dbrenn]

4 hours ago, Pilotman said:

At idle in normal operations, say in landing. the new software is still required to keep the aircraft flying in stable configuration.  I have explained this earlier, with the CoG forward of the CoP it will not glide to the required degree, it would quickly become uncontrollable.  One report asked why the crashed aircraft could not be controlled even with the engines at idle and producing  minimum thrust; that is the reason. The aircraft is dangerously unstable unless corrected by software.  That is all very well for military aircraft, that need to be agile and highly manoeuvrable, but it is insanely irresponsible in a civil airliner.  Ask yourself why Boeing had to upgrade and change the software system, rather than remove it altogether ? The reason is obvious, the aircraft will not fly, cannot fly without it. Boeing need to be charged with culpable manslaughter for the deaths and someone, maybe quite a few of their people need to be in  jail. I like Boeings.  I have flown them and appreciated their engineering excellence,.  In this case, they made a grave error and they need to pay for it. But of course they will not. 

That's terrible. There was also a documentary on TV that went undercover in the Dreamliner factory - itinerant labour has replaced skilled engineers with years of service. Staff joking around and cutting corners, leaving tools and trash behind inside aircraft sections.

 

If it's Boeing, I won't be going.