FAA: Wrestling with Appropriate Pilot Rating for EVTOLs

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Dana

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So many failure modes that can make it fall from the sky. Except... a well designed evtol could well have equal or better reliability and safety than a conventional helicopter, which people find acceptable. It doesn't have to be perfectly safe, just safe enough... whatever that is.
 

undean

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Note how long it is taking to get 2D autonomy working fully in cars. Flight is a much more complex regime, and all the things a pilot does are difficult to replicate in computer software (and hardware).

We're only at level 3 in cars. Sadly most don't understand what that even means or even care.


I dunno, I think autonomous flight is probably easier than driving. We already have it, pretty much, with autopilots in airliners including autoland. Airplanes don't have to worry about other cars shooting out from side streets, pedestrians, etc., or other unpredictable things.

The disturbing part is wondering what part of the sky will be left for us in our unpredictable manually controlled aircraft...

From the pilots view it's easier. From the designers it's so much more complicated. It's so complicated that the FAA and other governing bodies are having to relax safety standards to even allow it. Non-determinant computing, software that's all machine coded and bloated and glitchy, not properly or even close to fully regression tested, systems that aren't remotely integrated properly, etc.

As is often overlooked with auto pilots or even computer controlled flight systems: they are ok for standard flight parameters so long as everything is working properly. Once something happens they try to fix it. Once they have gotten into an unrecoverable situation it is dumped into the PIC hands. It then gets blamed on the PIC.

It's bad.
 

Dusan

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So many failure modes that can make it fall from the sky. Except... a well designed evtol could well have equal or better reliability and safety than a conventional helicopter, which people find acceptable. It doesn't have to be perfectly safe, just safe enough... whatever that is.
Err.. No - A multicopter does not auto-rotate, and cannot glide. It cannot "have equal or better reliability and safety than a conventional helicopter" since is lacking an inherent safety mechanism. A parachute is not an inherent safety mechanism. It needs to be deployed, it takes time and can malfunction since it's used in emergencies only. What do you do in case of a lightning strike and all the electronics gets fried? A small Cessna is not relying on electrical system to keep the engine running, it has magneto's. It happened more than once - the engine still running after a lighting strikes frying all electrical system onboard.
 

Pops

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If it will break, it will.
Went to work on a 200 ton capacity large bridge crane. ( monthly safety check list of 6 pages of items). Got up in the cab, started to move it to the end of the mile long building for the work. Contacts welded together on high speed. Got the main power off and got on the brakes and got it stopped at the end of the building right against the large stop blocks on the rails.
 

bmcj

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The problem with autonomous flight is that it will almost certainly will need some ground based Network connection to work within the system. This network connection will make it vulnerable to hacking, and you know that someone is going to try to hack them.
 

Dana

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Err.. No - A multicopter does not auto-rotate, and cannot glide. It cannot "have equal or better reliability and safety than a conventional helicopter" since is lacking an inherent safety mechanism. A parachute is not an inherent safety mechanism. It needs to be deployed, it takes time and can malfunction since it's used in emergencies only. What do you do in case of a lightning strike and all the electronics gets fried? A small Cessna is not relying on electrical system to keep the engine running, it has magneto's. It happened more than once - the engine still running after a lighting strikes frying all electrical system onboard.
Operational reliability is not the same thing as the ability to survive a failure. With fewer moving parts, a multicopter should be more reliable; whether it will be as safe overall depends on the reliability of the secondary safety mechanisms (BRS or whatever).
 
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