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Weightless: Parabolic flight on an A310

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Re: Weightless: Parabolic flight on an A310

#51

Post by segfaultbuserr »

I didn't know it's possible using an unmodified airplane. My first thought was: wouldn't this maneuver simultaneously set off all the alarms bells in the cockpit, as if the plane is crashing to the ground? After a quick search on YouTube, it indeed does, but not really a big deal...

> 2:43 - This parabolic manoeuvre isn't the normal kind of thing that you do in an Airbus, and the software in this plane hasn't been modified because to do so would be a huge effort to re-qualify it. With the normal software, you have the normal alarm saying, "This doesn't seem like a very good idea, guys," and one of the pilots that isn't too busy on the other two axes is turning off the alarms that we don't need to worry about and keeping track of the ones we might need to worry about.

https://www.youtube.com/watch?v=FO_Ox_dH0M8

Re: Weightless: Parabolic flight on an A310

#52

Post by jaywalk »

rbanffy wrote: post #46
groby_b wrote: post #31

Earlier quoted context omitted.

All the autopilots in the world aren't keeping a plane to within an inch in all three dimensions. It'd be nice, but turbulence is a thing :) More importantly, actual position isn't that important - you care about relative acceleration being as close to 0g as you can. And with the 3-pilot setup the A310 zero g flights have, they maintain +/- 0.02g. Now you add to that the fact that developing an autopilot you can trus…

The “easy” way to do it is to mandate autopilots to have the capability for precise ballistic trajectories. This would need better positioning, accelerometers, and meteorological radars and would also enable fully autonomous landings (if the plane can be aware of air densities and speeds around it, it can nail the landing even with wind gusts).

Most passenger airliners flying today can land automatically, but are only allowed to do so when visibility is so bad that it's the only option. It's called CAT III Autoland.

Re: Weightless: Parabolic flight on an A310

#53

Post by qwertox »

smackay wrote: post #34

The Portuguese Space Agency (yes, there is one, Go Portugal) recently ran a competition for teens to fly with Air Zero G. Thirty kids, including my son (majority were girls), shipped out today for the Air Force base at Beja. They fly on Friday.

Congratulations for him and his peers for having the opportunity to experience this. I can imagine that this will have a long lasting effect on their minds. It would be great to know what it did with him and the others in 10 years.

Re: Weightless: Parabolic flight on an A310

#56

Post by rbanffy »

groby_b wrote: post #49
rbanffy wrote: post #46

Earlier quoted context omitted.

The “easy” way to do it is to mandate autopilots to have the capability for precise ballistic trajectories. This would need better positioning, accelerometers, and meteorological radars and would also enable fully autonomous landings (if the plane can be aware of air densities and speeds around it, it can nail the landing even with wind gusts).

Wait what? If your landings are a ballistic trajectory, kindly step away from that stick ;) And that's kind of the point - nobody except the few planes that fly parabolic trajectories needs this. So good luck mandating something affecting all of aviation with no practical use except for a handful of flights. Autoland already exists. And can handle crosswinds up to 25kts. It's just that using them is an incredibly int…

I didn’t say parabolic landings. I said the same capabilities required to fully automate parabolic flights would allow safer landings because precise trajectory control even when there is turbulence around the plane is a very desirable feature.

On second thought, it could pay for itself in preventing aborted landings.

Re: Weightless: Parabolic flight on an A310

#58

Post by majou »

wil421 wrote: post #16
helsinkiandrew wrote: post #13

There's some scary videos from the cockpit in an A300 and (I think an) A310 doing parabolas: https://www.youtube.com/watch?v=Ty5B-7CinB8 https://www.youtube.com/watch?v=f-pMLZP6HL8

Wow that last one was pretty crazy to see. I guess they had some camera rig that would keep the camera level with the horizon.

> Both shots are from the GoPro Fusion camera.

> The cockpit footage is stabilised in post using Adobe After Effects and the telemetry from the plane's sensors.

Re: Weightless: Parabolic flight on an A310

#59

Post by ncmncm »

chasd00 wrote: post #23
laverya wrote: post #8

Earlier quoted context omitted.

The real question is "does it cost more to certify the autopilot to do this than it does to pay for an extra two pilots", and with my understanding of aerospace costs that answer would be "very, very much yes".

a pixhawk, ardupilot, some Lua, and a handful of servos and you're there. ;)

On an A310 you don't even need the servos.

But you probably want better than 8 bits resolution on sensors and output.

Re: Weightless: Parabolic flight on an A310

#60

Post by Napsty »

smackay wrote: post #34

The Portuguese Space Agency (yes, there is one, Go Portugal) recently ran a competition for teens to fly with Air Zero G. Thirty kids, including my son (majority were girls), shipped out today for the Air Force base at Beja. They fly on Friday.

That's awesome!
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