Would you fly on this plane?

[cctaylor]

My point, directed at Cutting42; why clam that only America has refused to ground the aircraft in question when this is not the case. The plane is still flying in Canada and Mexico.

Canada have now caught up with the rest of the world.

 

[Kraus]

So Trump does it!

Well done Pres.

All 737 max grounded world wide.

I hope he told his chums to sell Boeing.

 

[cctaylor]

I feel much better now that they are grounded. Having read a lot of the pprune thread it confirms my concerns.

Boeing have taken to using engineering trickery to try and overcome the aerodynamic problems caused by the new engines and the way they had to mount them. The solution they chose relies on a single sensor which in certain circumstances has total control over the aircraft pitch.

 

[cutting42]

If you look at person miles flown they're safe, if you look at safe take offs vs death they really arent.

I was thinking about this and the fear element of flying vs statistical safety of it. The number of take off's per death is an interesting stat as the miles covered is less relevant generally, it is the number of take off and landing that count. It is I believe how airframes are aged, not by miles but cycles.

 

[Paul R]

Angle of attack sensors are different to pitot tubes though.

Wow.

And even so, being located in different positions doesn't explain why, being heated, two would ice up and a third not.

Why would icing conditions be the same at the nose as at the tail?

It's noise. There is no good reason why having triple redundancy on this particular sensor would necessarily make the system safer. We do not know how the system works. Having redundancy on a critical system rather than single sensor makes more overt sense, but that is way off topic.

A much more obvious question is why a system solely intended to ensure increasing stick movement is required to hold increasing angles of attack during a test flight should operate at all when there is no stick movement, no pitch change and continues to operate at very high (for the height) speeds. I think whatever causes these crashes have, it will be a cascade of conditions followed by pilot incompetency.

 

[sean99]

I was thinking about this and the fear element of flying vs statistical safety of it. The number of take off's per death is an interesting stat as the miles covered is less relevant generally, it is the number of take off and landing that count. It is I believe how airframes are aged, not by miles but cycles.

Old pilot joke:
"Takeoffs are optional. Landings are mandatory. A good landing is one where everyone can walk away".

And another
"There are old pilots and there are bold pilots, but there are no old, bold pilots."

My late father was a navigator back in the 4 crew days then a flight engineer.

 

[stevec67]

I was thinking about this and the fear element of flying vs statistical safety of it. The number of take off's per death is an interesting stat as the miles covered is less relevant generally, it is the number of take off and landing that count. It is I believe how airframes are aged, not by miles but cycles.

That makes a lot of sense. Takeoffs are the most dangerous bit because you are flat out and have no height to play with so fewer choices. Any bloody idiot can fly a working plane once it's in the air, I've done it and I haven't got a clue. I handed the stick back to the man who knew what he was doing for the landing, naturally.

 

[Mullardman]

RE: Aircraft Safety Stats.

As an old Psychology lecturer at Uni stated. " Your chances of dying in an aircrash may be less than 0.0000001%.. but, if you die in an air crash.. you are 100% dead."

 

[cutting42]

That makes a lot of sense. Takeoffs are the most dangerous bit because you are flat out and have no height to play with so fewer choices. Any bloody idiot can fly a working plane once it's in the air, I've done it and I haven't got a clue. I handed the stick back to the man who knew what he was doing for the landing, naturally.

I found this table:

Here

Further thoughts. The comparison of cycles is also flawed as a car journey is just as dangerous throughout the journey as it is at the start or end, the mileage makes a difference as you have longer at risk from other road users, inattention etc.

The risk level is also very different, as Mull states, if a plane crashes you are almost 100% going to die whereas if a car crashes the odds are considerable better. Most of us have been in a car crash and none of us have died yet!

I guess that is why most comparisons use miles per death as it is relatively easy to compare but it is still an incomplete comparison.

 

[wacko]

Boeing have severely damaged their brand. To have Trump make a better decision is some achievement. They will lose $ billions of orders.
Great for Airbus as the UK chooses to turn its back on the EU.

 

[Bob McC]

Airbus have already said they will consider leaving the UK if we leave with no deal and that once we are out they will reconsider the financial viability of continuing to make any parts of new projects in the UK.

 

[stevec67]

I found this table:

Here

Further thoughts. The comparison of cycles is also flawed as a car journey is just as dangerous throughout the journey as it is at the start or end, the mileage makes a difference as you have longer at risk from other road users, inattention etc.

The risk level is also very different, as Mull states, if a plane crashes you are almost 100% going to die whereas if a car crashes the odds are considerable better. Most of us have been in a car crash and none of us have died yet!

I guess that is why most comparisons use miles per death as it is relatively easy to compare but it is still an incomplete comparison.

Agreed. Similar considerations apply when you compare motorised traffic accidents with cycling or pedestrians, do you use per hour or per mile? The difference in speed makes them very different, before you even think about different severity. Risk perception is fascinating, rock climbing is viewed as a very dangerous sport practiced by daredevils who are unlikely to see 30. I'm a lifelong climber, I have 3 prematurely dead climbing friends. One in a car, one a motorcycle, one failed abseil while climbing. My closest approach to death was when my bicycle was in collision with a car. Yet it's climbers who are the crazy risk takers.

 

[Sue Pertwee-Tyr]

Wow.

Well, it was you that seemed to conflate pitot tubes with AoA sensors by talking about pitot tubes, when the subject was AoA sensors.

Why would icing conditions be the same at the nose as at the tail?

Because the sensors have to agree, which means the conditions they have to measure have to agree, otherwise there is no point in having them.

It's noise. There is no good reason why having triple redundancy on this particular sensor would necessarily make the system safer. We do not know how the system works. Having redundancy on a critical system rather than single sensor makes more overt sense, but that is way off topic

A much more obvious question is why a system solely intended to ensure increasing stick movement is required to hold increasing angles of attack during a test flight should operate at all when there is no stick movement, no pitch change and continues to operate at very high (for the height) speeds. I think whatever causes these crashes have, it will be a cascade of conditions followed by pilot incompetency.

Not sure I understand your last point. When you pitch up, you don't keep pulling the stick back increasingly, you make a control input and hold it, the aircraft will continue to pitch up until a new equilibrium is reached based on the control inputs selected. Just like you don't keep turning the steering wheel more and more to get round a corner.

My understanding is that there is a system new to the 737 Max, which is coupled to the autopilot. Most times nowadays, the aircraft is flown through the autopilot, not through the stick. You ask the autopilot to do what you want, and the aircraft responds, you don't make control inputs to the same effect.

This puts a lot of reliance on the autopilot, and some crews are more reluctant to hand fly the aircraft and have got out of the habit of doing so. More, they have got into the habit of doing everything through the autopilot. As I understand it, the scenario for Lion Air, and possibly for Ethiopian, could possibly have been resolved if the crew had just switched off the autopilot and manually flown the aircraft. Instead, they tried to fight the autopilot by wrestling with the controls. Effectively a 737 is stronger than two blokes when it comes down to it.

 

[I.D.C.]

Flew for years abroad with my work at the time was flying back and forth to Brazil with air France at the time their plane fell out the sky that made me think. Have been in two emergency landings one of which a BA captain wished all the passengers good luck. Now I am uncomfortable on any plane had a recent holiday in Bali so will go planes but can't say I enjoy flights anymore.

 

[Derek Wright]

Please tell us more

 

[Mullardman]

This puts a lot of reliance on the autopilot, and some crews are more reluctant to hand fly the aircraft and have got out of the habit of doing so. More, they have got into the habit of doing everything through the autopilot. As I understand it, the scenario for Lion Air, and possibly for Ethiopian, could possibly have been resolved if the crew had just switched off the autopilot and manually flown the aircraft. Instead, they tried to fight the autopilot by wrestling with the controls. Effectively a 737 is stronger than two blokes when it comes down to it.

I recall a report saying that the Lion Air flight was lost because the crew did not switch off an anti stall system which was operating incorrectly. I'm not sure whether they actually knew how to do so and 'forgot' or what, but such an outcome simply shouldn't be possible.
The implication was that this 'system', was outside of the autopilot and could have been switched off separately.

I'd make a small wager that the same, or very similar happened to the Ethiopian flight. vThis because I find it hard to accept that crew would not switch off autopilot in a clearly 'wrong' situation, but it is possible they were unaware of the possibility of switching off the anti stall.

 

[gintonic]

Flew for years abroad with my work at the time was flying back and forth to Brazil with air France at the time their plane fell out the sky that made me think. Have been in two emergency landings one of which a BA captain wished all the passengers good luck. Now I am uncomfortable on any plane had a recent holiday in Bali so will go planes but can't say I enjoy flights anymore.

I am with you all the way. I have been in two emergency landings, one where the front under carriage was damaged, and another where the weather was so poor we were blown off the runway on landing.

I flew so much in about 12 years of my career I learnt to hate flying. Even with my Mrs paying for J class seats, it was still an unenjoyable experience. I recall getting back from Lagos, and my Mrs telling me she'd booked a lovely holiday in Bali, and I didnt want to go, I didnt want to fly or stay in top notch hotels.....

Wind forward nearly a decade since I stopped flying for work, and I still hate long haul, and can tolerate short haul. Later this years we are off to the Isles of Scilly, a 15 minute flight yahooo.

 

[wacko]

There are only two relatively risky parts of a flight: takeoff and landing. I hate short flights as the airport hassle is longer than the flight. Perfect flight time to me is 4-7 hours.

 

[johnhunt]

RE: Aircraft Safety Stats.

As an old Psychology lecturer at Uni stated. " Your chances of dying in an aircrash may be less than 0.0000001%.. but, if you die in an air crash.. you are 100% dead."

Low probability, high impact . Pass the RA

 

[stevec67]

There are only two relatively risky parts of a flight: takeoff and landing. I hate short flights as the airport hassle is longer than the flight. Perfect flight time to me is 4-7 hours.

Hardly. I flew to Ireland and back every week in December and January. No real hassle at the airport. Half an hour queuing and getting my bags x rayed, then half an hour hanging about drinking coffee or having a pint. What hassle? The 45 minute flight was long enough, I was invariably asleep before they had finished the safety announcement and by the time I'd woken up the pilot had taken his foot off and we had started the descent. Compared to a Friday night on the fu**ing M1 it was like a holiday camp.