We’re well into speculation territory here, but, if the anti stall is pushing down, it is no longer working as intended.

There is a preliminary report on Lion air.

But how the shuddering **** has this been released as a production aircraft without *someone* thinking that perhaps the input from the altimeter might be a useful thing to consider? There’s an instrument right there saying “you’re 100m away from crashing”, and yet the software still continues to push the nose down?!

The GPWS and TAWS systems are there to provide that (altitude + terrain) information to the pilot in terms of a series of audible warnings. These systems can be used to auto land an aircraft, but often only at airports with local GPS correction and only on aircarft so equipped (A320 etc). the systems isn’t automated as it’s usually not required to be automated, the warnings are there for landing which is well planned and has energy/margin to correct.

Automation of the antistall is somewhat more critical. If not automated, it’s surprisingly easy to keep nosing up and to stall the airflow on the wing and starve the engines of air. This essentially reduces energy on the aircraft to zero (ignoring potential) and the aircraft falls from the sky until such time as airspeed increases and the wings again begin to deliver lift. During take-off there isn’t time for this, the plane crashes first.

I think – may be wrong – the anti-stall on the MAX is off when flaps are deployed, i.e. during take off.

We’re well into speculation territory here, but, if the anti stall is pushing down, it is no longer working as intended.

There is a preliminary report on Lion air.

Agreed.

It’s not pushing down per-say, but it’s preventing pulling up as that would reduce the airspeed.

incidentally, preliminary report for lion air

https://spectrum.ieee.org/riskfactor/aerospace/aviation/indonesias-safety-committee-releases-preliminary-report-into-lion-air-crash

I thought MACS was in use in all phases of flight after WOW release due to the inherent tendencies of the larger (more forward mounted) engined 737s to pitch-up after at higher angles of attack? The larger 737s have a limited rotation angle which (i thought) means they had to pitch slightly more aggressively after takeoff.

the inherent tendencies of the larger (more forward mounted) engined 737s to pitch-up after at higher angles of attack?

This part I don’t understand. So they had to move the engines forward and upward to give ground clearance. That would move the center of gravity forward relative to the aerodynamic center of pressure, so the aircraft should tend to nose down. However, the newer models have also been stretched, plus aerodynamics have been revised, so surely all that should have been integrated to keep the aircraft stable when it’s properly loaded. Unless Boeing really screwed the dog, of course.

Edit. Explained here. https://theaircurrent.com/aviation-safety/what-is-the-boeing-737-max-maneuvering-characteristics-augmentation-system-mcas-jt610/

Just announced UK has blocked the aircraft from flying over UK airspace.

Ignore me

It would appear that the vairous aviation authorities are effectively grounding the fleet. Which saves me from having to work out if I’m flying on one in the near future – and demanding a different flight.

Phew, two very similar appearing incidents in the first two years of operation does point to either a serious design flaw, a serious flaw in the conversion training of the air crews, or both.

Which saves me from having to work out if I’m flying on one in the near future – and demanding a different flight.

Yep, quite glad about that, as I’m flying next week…

But how the shuddering **** has this been released as a production aircraft without *someone* thinking that perhaps the input from the altimeter might be a useful thing to consider?

Altimeter not a reliable source for critical situations.

Trump’s knows what the problem is. All this new technology, apparently.

Airplanes are becoming far too complex to fly. Pilots are no longer needed, but rather computer scientists from MIT. I see it all the time in many products. Always seeking to go one unnecessary step further, when often old and simpler is far better. Split second decisions are….

— Donald J. Trump (@realDonaldTrump) March 12, 2019

….needed, and the complexity creates danger. All of this for great cost yet very little gain. I don’t know about you, but I don’t want Albert Einstein to be my pilot. I want great flying professionals that are allowed to easily and quickly take control of a plane!

— Donald J. Trump (@realDonaldTrump) March 12, 2019

Amusingly, given what we currently know of the issues with that plane, he could actually be correct! Although a wiser man would shut up about it until after the investigations have concluded, also, nice job protecting Boeing, a US company, last I checked.

Amusingly, given what we currently know of the issues with that plane, he could actually be correct!

The most amusing thing about those tweets is it took 12 minutes between the first one and the second one being posted which is ironic given the topic of split second decisions…

Wonder if he knows about the autopilot thing on Air Force One…?

I’m reading “Hello World: How to be Human in the Age of the Machine” at the moment, about algorithms/AI stuff.

The Air France crash is discussed in the section on self-driving cars, and the general point is made that the more assistance people have from auto-drive/self-drive, the less capable they’ll be when they have to intervene in an emergency simply through lack of practice. It mentions that the AF junior pilot had clocked 3000 hours or so, but most of them would have been watching the auto-pilot rather than flying the plane.

Old and simple. That’s Trump.

…the general point is made that the more assistance people have from auto-drive/self-drive, the less capable they’ll be when they have to intervene in an emergency simply through lack of practice.

Even if this is true, auto pilot/self drive may still be the correct decision if it is safer overall. If the auto pilot prevents 99% of accidents that would normally result from human limitations or error, you wouldn’t turn it off just so the human has more practice for the remaining 1% of incidents.

From 1970 to 2018 fatalities per trillion revenue passenger kilometres decreased 54 fold from 3,218 to 59. Old and simple was better, eh Donald.

Trump is such a tube.

I was in the Cheviots a couple of weeks ago and in the Manor Valley there is a beautiful memorial to all of the aircrew lost in the area during the second world war. 19 aircraft al lwithin a few miles and (I think I am right in saying) not a single one shot down. All flew into ground. All because they were being flown by humans without technology to back them up.

Humans go into a funk when technology isn’t doing what they expect. Look at all the YouTube videos of runaway automatic cars to see what happens.

From 1970 to 2018 fatalities per trillion revenue passenger kilometres decreased 54 fold from 3,218 to 59. Old and simple was better, eh Donald.

There is probably a balance to be found somewhere in terms of automation vs making sure that humans are capable of and have the tools available on hand to correct automatic systems when they go wrong.

There is probably a balance to be found somewhere in terms of automation vs making sure that humans are capable of and have the tools available on hand to correct automatic systems when they go wrong.

CAA has stopped UK reg aircraft flying and all MAX aircraft from UK airspace.

Check out @UK_CAA’s Tweet: https://twitter.com/UK_CAA/status/1105461217886375937?s=09

From 1970 to 2018 fatalities per trillion revenue passenger kilometres decreased 54 fold from 3,218 to 59. Old and simple was better, eh Donald

It’s not just tech Vs pilot error though.
https://www.popularmechanics.com/flight/g73/12-airplane-crashes-that-changed-aviation/

It mentions that the AF junior pilot had clocked 3000 hours or so, but most of them would have been watching the auto-pilot rather than flying the plane.

I might well be wrong (and not for the first time… ) but I think, if AF447 had been left to autopilot, it wouldn’t have crashed. They were confused by the info conflicts (which put it into alternate law, which turned off the anti-stall, I think?), and they weren’t clear about who was in charge (captain was on a rest break) – the junior pilot pulled the nose up without telling his oppo he was doing it and just kept them stalled to the end. 🙁

There is probably a balance to be found somewhere in terms of automation vs making sure that humans are capable of and have the tools available on hand to correct automatic systems when they go wrong.

The anti stall does have an off switch, pilots need to use it to override, stick pulling won’t work. It may not be to blame in this crash, but it sounds a right crappy system. A third sensor for proper redundancy would be a start…

if AF447 had been left to autopilot, it wouldn’t have crashed. They were confused by the info conflicts (which put it into alternate law

AF447, being a bus, has a proper fly by wire system. It behaves quite differently to the Boeing version. When AF447 got confusing data, it switched to alterate law which switches off the autopilot. Basically if the autopilot gets conflicting inputs it goes “WTF – I’m outta here, you have the plane”. The pilots then reacted improperly, and alternate law does not protect the flight envelope in the way normal law does so they crashed.

Ah – fair enoughski, I stands corrected, ta. 🙂

So pretty much only the US left flying this plane now.
Seems the FAA don’t want to admit that they plane they said was safe may not actually be so.

19 aircraft al lwithin a few miles and (I think I am right in saying) not a single one shot down. All flew into ground. All because they were being flown by humans without technology to back them up.

All because they were very young men, training to become pilots very, very quickly, often in adverse conditions, which, more often than not, resulted in them flying into a cloud stuffed with rocks.
Similar things can happen even with aircraft fitted with modern technology.

But it doesn’t happen very often, I think, is the point.

I just shared that report with a colleague who used to work in the aviation industry. His comment was “MCAS = Make Craft A Shovel.”

So pretty much only the US left flying this plane now.

…and Canada, because it mainly follows its big brother. Even Air Canada’s own crews are saying they don’t want to fly on them.

“and Canada” – Not anymore… they’ve just followed most of the world “following new information”

The pilots then reacted improperly, and alternate law does not protect the flight envelope in the way normal law does so they crashed.

AIUI didn’t one pilot observe the plane was nose diving and tried to pull up, the other observed that it had stalled, causing the dive, and pushed down to gain speed, and because it’s flyby wire the plane just summed the two sticks and flew itself straight into the sea?

AIUI didn’t one pilot observe the plane was nose diving and tried to pull up, the other observed that it had stalled, causing the dive, and pushed down to gain speed, and because it’s flyby wire the plane just summed the two sticks and flew itself straight into the sea?

That was my understanding. The aircraft took the average input and it was only in the last seconds that one of the pilots realised that the other one had been providing an opposite input the whole time….

the plane just summed the two sticks and flew itself straight into the sea?

Not at all. Read what happened here:

https://www.popularmechanics.com/flight/a3115/what-really-happened-aboard-air-france-447-6611877/

Not at all. Read what happened here:

Read from 2:12:15 onwards. It’s not what caused the descent, but is why they didn’t correct it even once they realised what had happened.

The plane may have been averaging inputs for those few seconds, but it didn’t fly itself into the sea.

sweaman2

Member

“and Canada” – Not anymore… they’ve just followed most of the world “following new information”

Phew!