Perlan II Project Aims To Fly a Glider To the Edge of Space 44
Zothecula writes: In an ambitious attempt to break every wing-borne sustained flight height record for a manned aircraft, the Perlan ll project intends to construct and fly a glider higher than any sailplane has gone before. Riding on the colossal stratospheric air waves generated over mountains, the team plans to fly their craft to more than 90,000 ft (27,000 m), which will shatter their own existing glider altitude record of 50,671 ft (15,400 m) set by Perlan l in 2008.
100km (Score:5, Insightful)
At 27km up, you're closer to ground than to the edge of space. Stop sensationalizing.
Re:100km (Score:4, Insightful)
That was my first thought as well. Don't get me wrong, it will be an impressive feat, but it's nowhere near 'the edge of space'. I haven't done the math or looked it up but one would probably see the curvature of the Earth more noticeably than at sea level, but still, the title of this entry is complete sensationalism.
Re:Why manned? (Score:1, Insightful)
maybe they want controllable to the point of a safely retrievable and significant (by mass, not necessarily nature) payload?
Sure, maybe they do? I read their goals though, that's not in there anywhere. They want to set an altitude record, prove the aerodynamics work, and the meteorology simulations. Their third goal goal of inspiring young people might somehow justify putting a person in it. Anyway, if as you said they want to prove it can carry some weight, throw in a fancy video camera or something, of heck, even a rock accomplishes that as well as a person does. If your first choice of example significant mass is a human, it makes me wonder...
Also, human reflexes can adapt to unexpected aerodynamic situations much more intuitively than a computer can (I personally don't know of any system which can make an autonomous recovery from a flat spin), which ironically makes the mission more survivable.
Bullshit. They are going to have extensive practice flights to learn to control this monster, its not intuitive human reflex. They could just as easily train a computer to fly it. With one simple google search I found this paper [nt.ntnu.no] that covers research for spin recovery algorithms for autonomous planes, specifically mentioning
"In flying manned aircraft, recovery from
spins (and flat spins) requires moving control surfaces in
non-intuitive directions, generally speeding up the descent
in order to increase airflow over the control surfaces,
reinstate control, and subsequently pull up into level flight."
Then goes on to cover their work deriving and optimizing spin recovery algorithms for autonomous planes. This is not the first work in the area, and its not new. A computer can do a near optimal exit from a flat spin these days, while humans often screw it up and require special training to not do exactly the wrong thing (since the correct thing is counter intuitive!). I don't get why people thing they are magically better than a computer at physics simulation with a fixed set of sensor inputs... For cars the hard problem is recognizing all the objects and traffic: flying planes is just basic physics. I'm a computer engineer: I'm confident over the time of a flight-school I could code a better pilot then I could become especially for that kind of plane.
Any if you want a person controlling it (seems silly to me), they can do that from the ground: wanting a human in control does not all all provide a reason to put on onboard. The latency is small, and they already have a radio link. And how is sitting in a office flying via radio less survivable than being in the plane...
As to cabin safety, it's as simple as a pressure suit and a parachute. Remember we're dealing with an experimental aircraft here, not the First Class cabin on a Delta flight.
Chairs, physical steering controls, redundant re breathers, oxygen, physical instrument displays, windows etc. Then theres things like doors, labels, handles etc. The cockpit adds a lot of drag and wright too. You could remove all these if you ditched the people (and save a ton of weight and shape constraints). Also having people onboard limits flight duration (there is no bathroom, room for food, water or sleep). A plane like this could easily fly for days if they left the people off: Its riding wind patterns that are permanent.