5 ms·
This thing is a small fin on a swivel. It's a wind vane about 6 inches long, sticking out into a 500 mph airstream. It's a heavy-duty piece of metal, but that s
by dreamcompiler 8y ago
This thing is a small fin on a swivel. It's a wind vane about 6 inches long, sticking out into a 500 mph airstream. It's a heavy-duty piece of metal, but that swivel joint makes it vulnerable to bird strikes, freezing, etc.
- dboreham 8y agoHmm...if it works that way it seems quite easy to determine if it is working -- if it isn't swiveling then it is probably broken. Perhaps also you could make an active version of this sensor where there's a stepper that pushes it a bit either side of the current neutral position, then measure resistance to that push with a strain gauge. It might be possible to thereby know that you're pushing against flowing air, not bird guts jammed in the mechanism, for example.
- dreamcompiler 8y agoProbably could be done but it would require significant reengineering because it introduces new failure modes. Best approach is what everybody else does: Assume the AoA sensor can fail and design the software accordingly. Boeing didn't do that and the results were fatal.
- noir_lord 8y agoUse an odd number > 1 and sound an alert if they can't reach a quorum. Triple redundancy is pretty common in safety critical systems.
- cesarb 8y ago> if it isn't swiveling then it is probably broken According to https://www.satcom.guru/2019/04/what-happened-on-et302.html https://www.satcom.guru/2019/04/what-happened-on-et302.html it was swiveling freely because it was broken.