Ethiopian plane crash

[PRTVR]

George Smiley said:

PRTVR said:

but don't modern aircraft have systems to limit the action's of the pilot to maintain the flight envelope? Are we not talking about an addition to to the specifications,
My point about the likes of the B2 was what at the extreme end of the spectrum what was possible not that civilian aircraft are the same.

Not the same.

They have laws which protect from the pilot doing something that would put the flight in danger.

Mcas is about using software to control the pitch of the aircraft to overcome lift due to the engines being too big, too low and too far forward.

Is not each aircraft different in regards what action would put the aircraft in danger ? Take concorde compared to a Jumbo jet,
could the max be flown without the Mcas with training , the answer is yes, Boeing were trying to get away without expensive training by utilising Mcas, in my view that was the major problem, not that the aircraft is inherently unsafe.
Where the engines are placed is not fixed, a Fokker aircraft had its engines on top of the wings, were the engines are placed is not relevant unless you are trying to tell everyone that its just like the previous 737 which it obviously isn't.

[George Smiley]

Except the engines are the problem

They didn’t want to engineer larger landing gear so you now end up with engines that want to make the plane loopdeloop when on full power such as take off.

It’s what happens when you try to make a nearly 60 year old plane used today

[Munter]

George Smiley said:

They didn’t want to engineer larger landing gear so you now end up with engines that want to make the plane loopdeloop when on full power such as take off.

I could swear the problem was related to angle of attack, and the "lift" then generated by the new location and size of the engine cowling beyond a certain angle, and not as such the power applied. Thus a system introduced to stop the thing going beyond that "safe" angle, without automatically putting in correction.

[George Smiley]

Munter said:

I could swear the problem was related to angle of attack, and the "lift" then generated by the new location and size of the engine cowling beyond a certain angle, and not as such the power applied. Thus a system introduced to stop the thing going beyond that "safe" angle, without automatically putting in correction.

Which is what I said

[Munter]

George Smiley said:

Munter said:

I could swear the problem was related to angle of attack, and the "lift" then generated by the new location and size of the engine cowling beyond a certain angle, and not as such the power applied. Thus a system introduced to stop the thing going beyond that "safe" angle, without automatically putting in correction.

Which is what I said

Good stuff.

So you agree it's about limiting the flight envelope like other systems on passenger jets, not some form of primary control without which the thing cannot fly.

[M4cruiser]

coanda said:

George Smiley said:

I can’t recalll airbus shovibg engines on a near 70 year old airframe and using software to counteract the situation

I didn't say that was the sensitive issue.

Both Airbus and Boeing have had issues related to the physical disconnect between the input controls and the results.
Not the same issue I agree, but similar enough to create life-threatening situations.

The Max does things the pilots didn't tell it to do. An Airbus can fail to do things the pilots tell it to do. Whether it's all caused by software covering up, misunderstandings, poor training, doesn't matter if the result is the same.

Cars do the same, but the results are not usually so catastrophic. Mostly with brakes at the moment, but maybe with steering soon.

[frisbee]

M4cruiser said:

Both Airbus and Boeing have had issues related to the physical disconnect between the input controls and the results.
Not the same issue I agree, but similar enough to create life-threatening situations.

The Max does things the pilots didn't tell it to do. An Airbus can fail to do things the pilots tell it to do. Whether it's all caused by software covering up, misunderstandings, poor training, doesn't matter if the result is the same.

Cars do the same, but the results are not usually so catastrophic. Mostly with brakes at the moment, but maybe with steering soon.

Nissan made a drive by wire steering system, IIRC triplex computers and a backup mechanical linkage. So nice and simple!

Some of the brake by wire systems are interesting as well, self servoing so they can operate on 12 volts. I'm surprised manufacturers haven't put more effort into brake by wire, ditch all the hydraulics, the servo, the ABS valves and pumps and replace it all with a few electric actuators.

Having had an RS Turbo, anything has to be better than mechanical ABS.

[captain_cynic]

PRTVR said:

But surely we are past the stage that software can limit problems ? Military aircraft are now running that would not fly without computer control, to utilise systems to protect the aircraft in a small part of the flight envelope doesn't appear unreasonable,

the problem arises when the system fails, as in the B2 bomber where reportedly three sensors fail,

for me the main problem has always been the single sensor, two sensors and an input from another source should have been a minimum, along with training if it fails.

Said military aircraft have ejection seats for that very reason.

Sure an F35 could never fly without software assistance.. but that assistance can go very wrong so the meat based pilot has an escape route.

Don't get me wrong, software assistance isn't automatically a bad thing. Airbus has done it successfully for nearly 30 years now. So has Boeing up until recently. With the Airbus system the default is always to throw control back to the pilot. An A320 contains 4 flight control computers, 3 in a quorum and 1 hot spare (in case one of the others fails), if the three in the quorum cant agree, they relinquish control and say "Sorry pilot, your plane now".

The fact that such systems have been designed to be so fantastically fault tolerant is why flying is so incredibly safe these days but ultimately the pilot should have final say in the control of the aircraft. Even if it is 1 in 1,000,000,000 events, that kind of backup is invaluable.

[hutchst]

M4cruiser said:

Both Airbus and Boeing have had issues related to the physical disconnect between the input controls and the results.
Not the same issue I agree, but similar enough to create life-threatening situations.

The Max does things the pilots didn't tell it to do. An Airbus can fail to do things the pilots tell it to do. Whether it's all caused by software covering up, misunderstandings, poor training, doesn't matter if the result is the same.

Cars do the same, but the results are not usually so catastrophic. Mostly with brakes at the moment, but maybe with steering soon.

The problem with the Max is that it carries on doing things the pilots didn't tell it to do, even after the pilots tell it not to do them any more, right up until it kills everybody on board.

[PRTVR]

hutchst said:

M4cruiser said:

Both Airbus and Boeing have had issues related to the physical disconnect between the input controls and the results.
Not the same issue I agree, but similar enough to create life-threatening situations.

The Max does things the pilots didn't tell it to do. An Airbus can fail to do things the pilots tell it to do. Whether it's all caused by software covering up, misunderstandings, poor training, doesn't matter if the result is the same.

Cars do the same, but the results are not usually so catastrophic. Mostly with brakes at the moment, but maybe with steering soon.

The problem with the Max is that it carries on doing things the pilots didn't tell it to do, even after the pilots tell it not to do them any more, right up until it kills everybody on board.

It's quite a dilemma, when do you allow the pilot control ? As the aircraft is hurtling to the ground with no chance of recovery, a voice in the cockpit says autopilot disengaged you have control, or do you allow safety systems to be easily overridden with possible disastrous consequences.
At present the pilot is in control but going forward I can envisage more automated control , if you look at cars and how that has come on with the likes of Tesla there is no reason to think that all means of transport will become more automated going forward .

[eccles]

PRTVR said:

hutchst said:

M4cruiser said:

Both Airbus and Boeing have had issues related to the physical disconnect between the input controls and the results.
Not the same issue I agree, but similar enough to create life-threatening situations.

The Max does things the pilots didn't tell it to do. An Airbus can fail to do things the pilots tell it to do. Whether it's all caused by software covering up, misunderstandings, poor training, doesn't matter if the result is the same.

Cars do the same, but the results are not usually so catastrophic. Mostly with brakes at the moment, but maybe with steering soon.

The problem with the Max is that it carries on doing things the pilots didn't tell it to do, even after the pilots tell it not to do them any more, right up until it kills everybody on board.

It's quite a dilemma, when do you allow the pilot control ? As the aircraft is hurtling to the ground with no chance of recovery, a voice in the cockpit says autopilot disengaged you have control, or do you allow safety systems to be easily overridden with possible disastrous consequences.
At present the pilot is in control but going forward I can envisage more automated control , if you look at cars and how that has come on with the likes of Tesla there is no reason to think that all means of transport will become more automated going forward .

I'm not sure we'll ever see it in Airliners.
A minute googling shows how many accidents have happened with Tesla vehicles, some fatal, some not. Pretty much any accident with an airliner is going to have fatalities involved, but you may well end up with hundreds of deaths, not just a couple here and there.

[PRTVR]

eccles said:

PRTVR said:

hutchst said:

M4cruiser said:

Both Airbus and Boeing have had issues related to the physical disconnect between the input controls and the results.
Not the same issue I agree, but similar enough to create life-threatening situations.

The Max does things the pilots didn't tell it to do. An Airbus can fail to do things the pilots tell it to do. Whether it's all caused by software covering up, misunderstandings, poor training, doesn't matter if the result is the same.

Cars do the same, but the results are not usually so catastrophic. Mostly with brakes at the moment, but maybe with steering soon.

The problem with the Max is that it carries on doing things the pilots didn't tell it to do, even after the pilots tell it not to do them any more, right up until it kills everybody on board.

It's quite a dilemma, when do you allow the pilot control ? As the aircraft is hurtling to the ground with no chance of recovery, a voice in the cockpit says autopilot disengaged you have control, or do you allow safety systems to be easily overridden with possible disastrous consequences.
At present the pilot is in control but going forward I can envisage more automated control , if you look at cars and how that has come on with the likes of Tesla there is no reason to think that all means of transport will become more automated going forward .

I'm not sure we'll ever see it in Airliners.
A minute googling shows how many accidents have happened with Tesla vehicles, some fatal, some not. Pretty much any accident with an airliner is going to have fatalities involved, but you may well end up with hundreds of deaths, not just a couple here and there.

I agree but what is often missed out when talking about Tesla is you can't quantify the number of lives saved due to the automation, everything is a trade off more automation will come to aircraft, but in small steps, rightly, that's the way the industry works.

[M4cruiser]

PRTVR said:

It's quite a dilemma, when do you allow the pilot control ? As the aircraft is hurtling to the ground with no chance of recovery, a voice in the cockpit says autopilot disengaged you have control, or do you allow safety systems to be easily overridden with possible disastrous consequences.
At present the pilot is in control but going forward I can envisage more automated control , if you look at cars and how that has come on with the likes of Tesla there is no reason to think that all means of transport will become more automated going forward .

Dilemma also is when do you allow the aircraft to override the pilot's control?
Two examples (I'm sure there have been more): AF447, the aircraft knew it was going to crash, yet it allowed the pilots to crash.
German Wings: likewise.

[anonymous-user]

M4cruiser said:

PRTVR said:

It's quite a dilemma, when do you allow the pilot control ? As the aircraft is hurtling to the ground with no chance of recovery, a voice in the cockpit says autopilot disengaged you have control, or do you allow safety systems to be easily overridden with possible disastrous consequences.
At present the pilot is in control but going forward I can envisage more automated control , if you look at cars and how that has come on with the likes of Tesla there is no reason to think that all means of transport will become more automated going forward .

Dilemma also is when do you allow the aircraft to override the pilot's control?
Two examples (I'm sure there have been more): AF447, the aircraft knew it was going to crash, yet it allowed the pilots to crash.
German Wings: likewise.

The MCAS was originally a high speed system to avoid high speed pitch up and protect from stalling, then in flight testing the issue with the engines showed the low speed pitch up characteristics so it got altered to cover that.

With MCAS the recovery was pretty straight forwards. Disengage the stab trim (to stop the aircraft electrical forwards trimming) and fly the aircraft.

Boeing max training was woeful initially, the CBT (computer based training) just said the max had a stall protection system, nothing about how it worked or what it did but certainly by the time of the second crash there was plenty of circulars about what to do if it went wrong.

Obviously there’s a debate about whether pilots should be having to recover the situation in the first place though.

I fly a pretty state of the art aircraft and the automatics are frequently doing weird things that might lead to undesirable outcomes. We’re constantly getting information from Boeing about software problems and what potential issues have resulted from them with other airlines etc. A fully automated passenger aircraft is a long way away.

Most of it doesn’t make the media as it hasn’t lead to crashes but most aircraft have been made with all kinds of issues that usually get ironed out over their long in service life.

Automation in civil aviation isn’t like in the military where it saves pilots from capture or allows higher g loads or more efficient designs and weight savings etc

Plus it’s not wanted by anyone (passengers, airlines, manufacturers) yet.

[Digga]

Starfighter said:

Military aircraft have higher acceptable risk levels, higher levels of pilot training and additional safety systems in the event of failure.

Crucially, both pIlot and co-pilot have means of escape - ejector - and there are no passengers.

[eldar]

El stovey said:

I fly a pretty state of the art aircraft and the automatics are frequently doing weird things that might lead to undesirable outcomes. We’re constantly getting information from Boeing about software problems and what potential issues have resulted from them with other airlines etc. A fully automated passenger aircraft is a long way away.

Most of it doesn’t make the media as it hasn’t lead to crashes but most aircraft have been made with all kinds of issues that usually get ironed out over their long in service life.

That sounds quite concerning. Leave it to the users to debug?

[anonymous-user]

eldar said:

El stovey said:

I fly a pretty state of the art aircraft and the automatics are frequently doing weird things that might lead to undesirable outcomes. We’re constantly getting information from Boeing about software problems and what potential issues have resulted from them with other airlines etc. A fully automated passenger aircraft is a long way away.

Most of it doesn’t make the media as it hasn’t lead to crashes but most aircraft have been made with all kinds of issues that usually get ironed out over their long in service life.

That sounds quite concerning. Leave it to the users to debug?

Something goes ‘wrong’ we sort it out and write a report that goes to Boeing if it happens enough then Boeing publish a circular with some advice (full of euphemisms in case it goes public) and a future update to fix it.

The point is that pilots are still needed to tell the manufacturers what’s happening and stop these faults leading to something else unexpected and maybe even worse happening.

Edited by anonymous-user on Tuesday 18th August 12:47

[Speed 3]

Design and testing is pretty digital/theoretically modelled these days. The actual flight test part of certification is much less than it used to be and can only test a finite number of scenarios within the normal operating envelope (and just on the limits of it) in an industry acceptable certification timeframe. Inevitably there will be things in the "real world" that don't crop up in the same way in testing, if at all over a protracted operating period. Add in humans (non test-pilot standard) and you can enter a whole new unforeseen ball game. Mostly that will be mitigated in some way (eg system redundancy, overrides, training etc) but it can't cover absolutely everything. Max happened to be a very public and tragic outcome where those mitigations were inadequate.

[hutchst]

El stovey said:

The MCAS was originally a high speed system to avoid high speed pitch up and protect from stalling, then in flight testing the issue with the engines showed the low speed pitch up characteristics so it got altered to cover that.

With MCAS the recovery was pretty straight forwards. Disengage the stab trim (to stop the aircraft electrical forwards trimming) and fly the aircraft.

Boeing max training was woeful initially, the CBT (computer based training) just said the max had a stall protection system, nothing about how it worked or what it did but certainly by the time of the second crash there was plenty of circulars about what to do if it went wrong.

Obviously there’s a debate about whether pilots should be having to recover the situation in the first place though.

I fly a pretty state of the art aircraft and the automatics are frequently doing weird things that might lead to undesirable outcomes. We’re constantly getting information from Boeing about software problems and what potential issues have resulted from them with other airlines etc. A fully automated passenger aircraft is a long way away.

Most of it doesn’t make the media as it hasn’t lead to crashes but most aircraft have been made with all kinds of issues that usually get ironed out over their long in service life.

Automation in civil aviation isn’t like in the military where it saves pilots from capture or allows higher g loads or more efficient designs and weight savings etc

Plus it’s not wanted by anyone (passengers, airlines, manufacturers) yet.

Aah, I see we're back to the old "third world pilots don't know how to fly these highly technical new aeroplanes" line of argument. It makes sense, obviously, because the manufacturers always ground the entire worldwide fleet for eighteen months because a couple of blokes in Ethiopia and Indonesia didn't read their emails.

Alternatively, these aeroplanes were flying death traps when they were released into service.

[anonymous-user]

hutchst said:

Aah, I see we're back to the old "third world pilots don't know how to fly these highly technical new aeroplanes" line of argument. It makes sense, obviously, because the manufacturers always ground the entire worldwide fleet for eighteen months because a couple of blokes in Ethiopia and Indonesia didn't read their emails.

Alternatively, these aeroplanes were flying death traps when they were released into service.

If you say so but I’m not sure where i mentioned third world pilots in my post.

Boeing for all their failings had released a lot of information about the MCAS problem before the second crash. It’s handled like a stab trim runaway situation by moving the stab trim to cut off.

Not sure which Boeings you’ve flown or where you work but there was a lot of information about the issue available at the time.

I agree it needs to be sorted but it’s not an unrecoverable situation if it happens, obviously you think differently.