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I think the main problem with aircraft is lack of redundancy. They still count on the ability of letting the pilots control the aircraft (e.g. .1% of the time a

I think the main problem with aircraft is lack of redundancy. They still count on the ability of letting the pilots control the aircraft (e.g. .1% of the time as you mentioned), I think they should just try to go all the way as much as possible. For example, if they had 4 redundant pilot tubes on different places and other redundant methods to measure altitude and airspeed the AP would never have disengaged. For a large plane those sensors are basically free, and it's very easy to tell whether they're working correctly by cross-verification/calibration (i.e. maintenance/reliability is easy) -- they just don't go all the way because they're still on the paradigm that "well if a couple pilot tubes and/or other systems fail we can just hand it to the pilot".

Animats 11y ago
"For example, if they had 4 redundant pilot tubes on different places and other redundant methods to measure altitude and airspeed the AP would never have disengaged." There's a lot to be said for that. The pilots didn't know their altitude and airspeed either. They thought they were overspeeding when they were stalling. Some military aircraft, mostly the stealth ones with terrible aerodynamic stability, need that sensor data to stay in the air at all. If they lose the sensor data or the stability control system, the only option is to eject. So they tend to go in for more sensor redundancy. There's certainly no reason that large transport aircraft can't have more sources of basic attitude/altitude/airspeed info.
noxryan 11y ago
Modern aircraft have excellent redundancy. Commercial aircraft already typically have 3 Pitot* tubes and 3 static ports. They need unobstructed airflow and are placed accordingly. In this kind of aircraft they do cross-verify each other as well, but if they all are reading different values, there's not much to be done. Conditions were such on AF447 that they all experienced some amount of icing until the aircraft descended enough. I don't see how having one more pitot tube is the proper response.
- darkmighty 11y ago
  Well clearly having altitude/velocity readings is critical to autopilot function, so some kind of redundancy should be put in place. Not necessarily specifically more pilot tubes, but some kind of solution, like heating/deicing the tubes inlets, better placing them, etc -- guaranteeing in some way the chances that all measurements are unavailable is astronomically low.
radialbrain 11y ago
Airbus A330s (the type used by AF447) already have 3 pitot tubes, two on one side of the airplane, and one on the other.
w0utert 11y ago
>> I think the main problem with aircraft is lack of redundancy. They still count on the ability of letting the pilots control the aircraft (e.g. .1% of the time as you mentioned), I think they should just try to go all the way as much as possible. I'm not an airliner pilot, but I have the impression almost everyone is always grossly underestimating how often a human pilot is still required to safely fly a commercial airliner. Yes, the autopilot may be able to handle 99% of the flights without intervention, or even 99.9% of the flights, but simple math shows that that means there are still tens if not hundreds of thousands of flights every day where the pilot needs to take action, and that any individual pilot will get into a situation where the autopilot will fail to handle a situation probably once or twice a year. Likely a lot more often. Large parts of the world have weather conditions, diversions, or airports with spotty or unreliable ground systems by the way, in those areas the need for a human pilot will be several times higher than once every hundred flights. There's ample examples of plane crashes that were caused by automated systems, rather than pilot error (I don't remember the exact location and date, but I know that e.g. not very long ago a plane crashed because the ILS beacon at the airport was malfunctioning). In other cases the level of automation enabled lousy pilots with bad training to fly the airplane (case in point: the Air Asiana crash at SFO), which IMO is not 'pilot error' because these people should not have been flying the plane in the first place. All this makes me think the solution to improve airliner safety even further is not more automation, but better pilot training. As for autonomous driving, besides AI assisted highway cruising, I don't believe in the concept at all, and my bet is that in 25 years we've realized that we've been wasting most of the time trying to build fully autonomous vehicles. Limiting the possibilities of driver error seems like a much better investment (e.g. automatic cruise control, automatic emergency braking, etc).

Animats 11y ago

"For example, if they had 4 redundant pilot tubes on different places and other redundant methods to measure altitude and airspeed the AP would never have disengaged." There's a lot to be said for that. The pilots didn't know their altitude and airspeed either. They thought they were overspeeding when they were stalling. Some military aircraft, mostly the stealth ones with terrible aerodynamic stability, need that sensor data to stay in the air at all. If they lose the sensor data or the stability control system, the only option is to eject. So they tend to go in for more sensor redundancy. There's certainly no reason that large transport aircraft can't have more sources of basic attitude/altitude/airspeed info.

noxryan 11y ago

Modern aircraft have excellent redundancy. Commercial aircraft already typically have 3 Pitot* tubes and 3 static ports. They need unobstructed airflow and are placed accordingly. In this kind of aircraft they do cross-verify each other as well, but if they all are reading different values, there's not much to be done. Conditions were such on AF447 that they all experienced some amount of icing until the aircraft descended enough. I don't see how having one more pitot tube is the proper response.

darkmighty 11y ago
Well clearly having altitude/velocity readings is critical to autopilot function, so some kind of redundancy should be put in place. Not necessarily specifically more pilot tubes, but some kind of solution, like heating/deicing the tubes inlets, better placing them, etc -- guaranteeing in some way the chances that all measurements are unavailable is astronomically low.

radialbrain 11y ago

Airbus A330s (the type used by AF447) already have 3 pitot tubes, two on one side of the airplane, and one on the other.

w0utert 11y ago

>> I think the main problem with aircraft is lack of redundancy. They still count on the ability of letting the pilots control the aircraft (e.g. .1% of the time as you mentioned), I think they should just try to go all the way as much as possible. I'm not an airliner pilot, but I have the impression almost everyone is always grossly underestimating how often a human pilot is still required to safely fly a commercial airliner. Yes, the autopilot may be able to handle 99% of the flights without intervention, or even 99.9% of the flights, but simple math shows that that means there are still tens if not hundreds of thousands of flights every day where the pilot needs to take action, and that any individual pilot will get into a situation where the autopilot will fail to handle a situation probably once or twice a year. Likely a lot more often. Large parts of the world have weather conditions, diversions, or airports with spotty or unreliable ground systems by the way, in those areas the need for a human pilot will be several times higher than once every hundred flights. There's ample examples of plane crashes that were caused by automated systems, rather than pilot error (I don't remember the exact location and date, but I know that e.g. not very long ago a plane crashed because the ILS beacon at the airport was malfunctioning). In other cases the level of automation enabled lousy pilots with bad training to fly the airplane (case in point: the Air Asiana crash at SFO), which IMO is not 'pilot error' because these people should not have been flying the plane in the first place. All this makes me think the solution to improve airliner safety even further is not more automation, but better pilot training. As for autonomous driving, besides AI assisted highway cruising, I don't believe in the concept at all, and my bet is that in 25 years we've realized that we've been wasting most of the time trying to build fully autonomous vehicles. Limiting the possibilities of driver error seems like a much better investment (e.g. automatic cruise control, automatic emergency braking, etc).