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Perlan II Project Aims To Fly a Glider To the Edge of Space

Soulskill posted about 2 months ago | from the bring-a-jacket,-it'll-be-chilly dept.

Transportation 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.

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100km (5, Insightful)

Anonymous Coward | about 2 months ago | (#47590395)

At 27km up, you're closer to ground than to the edge of space. Stop sensationalizing.

Re:100km (3, Insightful)

dreamchaser (49529) | about 2 months ago | (#47590453)

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:100km (2)

pushing-robot (1037830) | about 2 months ago | (#47590491)

I'll give them this one, considering one of the purposes of this project is to prove the feasability of extraterrrestrial flight in atmospheres as thin as that of Mars.

Re:100km (1)

pushing-robot (1037830) | about 2 months ago | (#47590507)

(...and I apparently have Tony the Tiger's spellchecker, since it completely missed that typo.)

Re:100km (0)

Anonymous Coward | about 2 months ago | (#47590523)

spellcheckerrrrrrrrrrrrrrrrrrrr

Re:100km (1)

Pikoro (844299) | about 2 months ago | (#47592841)

You're spell checker is Grrrrrrrrrrrrrrrrrrrrrrrrrrrrrreat!

Re:100km (1)

Pikoro (844299) | about 2 months ago | (#47592845)

Ouch. s/you're/your/ My spell czecher sucks.

Re:100km (1)

Concerned Onlooker (473481) | about 2 months ago | (#47592329)

If you do actually Google "where does space start" you'll get a popular definition of 100km, so yes, quite a bit short.

I'm also not sure yet about the claim that they had the previous record. If you visit http://www.fai.org/record-glid... [fai.org] you'll see that in 2006 the late great Steve Fossett has a claim to a little higher than the Perlan claim. The Perlan claim doesn't even show up on the site.

Re:100km (1)

matfud (464184) | about 2 months ago | (#47592515)

Steve Fosset was one of the pilots of Perlan 1

Re:100km (2)

Concerned Onlooker (473481) | about 2 months ago | (#47593897)

Self-penalty: no posting to Slashdot for at least two weeks.

Re:100km (1)

Mister Liberty (769145) | about 2 months ago | (#47590641)

I agree.
These are exercises in Semantics and Sophistry rather than Spaceflight or Physis.

Lunatics --I choose that word with purpose-- without any sense of proportion have taken over 'Space'.
They prob. even think the moon is one small glide further out.

Re: 100km (1)

Anonymous Coward | about 2 months ago | (#47590689)

Isn't something like 90+% of the atmosphere below you at that altitude? Only 10% more to go to reach vacuum. That seems to be the edge.

Re: 100km (4, Informative)

calidoscope (312571) | about 2 months ago | (#47591221)

Something on the order of 97% of the atmosphere's mass is below 90,000'. 100km is an arbitrary value for the start of space, as the air at 100km is too thick to orbit and too thin to fly in (except dynamic soaring?). In imperial units, 100,000' seems to be the upper limit for flying and 100 miles is about the lower limit for orbiting.

The Perlan II sounds like it will handle like an unpowered U2 - where the planes ceiling will be defined by the "coffin corner" were the low speed stall (classic stall) approaches the high speed stall (Mach tuck from transonic airflow). Perhaps they will be using a more refined airfoil than the U2 to increase the Mach number for high speed stall.

IIRC, the pre-Perlan I sailplane altitude record of approx 47,000 feet was set sometime in the 1960's, surprising it took that long for someone to break that.

Re: 100km (1)

iggymanz (596061) | about 2 months ago | (#47591449)

The "lower limit" is lower than that, the Zenit sattelites had a perigree of 135km, or 84 miles.

Re: 100km (0)

Anonymous Coward | about 2 months ago | (#47591551)

100,000' seems to be the upper limit for flying

Balloons and jet powered aircraft have made it over 120k ft, but 100k is probably within a factor of two of the limit any time soon for things that depend on air.

Re: 100km (0)

Anonymous Coward | about 2 months ago | (#47591589)

Balloons and jet powered aircraft have made it over 120k ft,

Manned balloons make it over 120k, unmanned have made it up to about 170k

Re: 100km (1)

Noah Haders (3621429) | about 2 months ago | (#47591989)

100k is probably within a factor of two of the limit any time soon for things that depend on air.

So the "limit for things that depend on air" will fall between 1,000 feet and 10,000,000 feet?

Re: 100km (0)

Anonymous Coward | about 2 months ago | (#47592937)

Umm, "within a factor of two" means somewhere between somewhere between 0.5x and 2x... or in a case where one direction is heavily implied, 2x. Factor of two doesn't mean two orders of magnitude. So ftfy:

So the "limit for things that depend on air" will fall between 50,000 feet and 200,000 feet?

Re: 100km (1, Interesting)

Anonymous Coward | about 2 months ago | (#47592047)

Isn't something like 90+% of the atmosphere below you at that altitude? Only 10% more to go to reach vacuum. That seems to be the edge.

When you stand at sea level, 99.99999% of the earth's mass is below you. So we are all at the edge of space.

Re:100km (2)

w0mprat (1317953) | about 2 months ago | (#47591503)

At 27km up, you're closer to ground than to the edge of space. Stop sensationalizing.

At 27km up your above 98% of the atmosphere if you go by density. It's not sensationalizing at all.

Re:100km (3, Informative)

jklovanc (1603149) | about 2 months ago | (#47592103)

The Kármán line [wikipedia.org] , or Karman line, lies at an altitude of 100 kilometres (62 mi) above the Earth's sea level, and commonly represents the boundary between the Earth's atmosphere and outer space. This definition is accepted by the Fédération Aéronautique Internationale (FAI), which is an international standard setting and record-keeping body for aeronautics and astronautics. By saing "edge of space" and then "90,000ft" (27.4km) they are making a mockery of the "Edge of space". When has 27.4% towards a goal ever been "close" to a goal? They further exagerate using this [gizmag.com] artist's rendering. The curvature of the earth would be much less. Here is an actual photo taken at 90,000ft.

In the end 27.4kM is not close to 100km and therefore not close to the edge of space. Sorry but you can't re-define something that has been internationally agreed upon to make your aircraft look better.

Stop this nonsense. (0, Interesting)

Anonymous Coward | about 2 months ago | (#47590407)

This is against the will of God.

Re:Stop this nonsense. (2)

aix tom (902140) | about 2 months ago | (#47593017)

Yeah!!! If God had wanted us to fly, he would have given us first class tickets!!

Re:Stop this nonsense. (0)

Anonymous Coward | about 2 months ago | (#47598787)

I'm afraid Concorde doesn't fly any more. Besides, it was only 60,000ft.

(Damn that was expensive, but I don't regret a penny of it)

glide into the edge (0, Informative)

Anonymous Coward | about 2 months ago | (#47590455)

of his anus

Re:glide into the edge (1)

PopeRatzo (965947) | about 2 months ago | (#47590533)

No, Uranus.

Re:glide into the edge (2)

ihtoit (3393327) | about 2 months ago | (#47590551)

sorry, didn't you get the memo? They changed the name to put that tired old joke to rest once and for all.

It's now "Urectum".

Re:glide into the edge (1)

PopeRatzo (965947) | about 2 months ago | (#47593307)

"Rectum"? Heck, I hardly knew him.

Or something like that.

Why manned? (0)

Anonymous Coward | about 2 months ago | (#47590515)

It seems safer, cheaper and easier to do this with an unmanned plane. It would also be able to be much lighter (no people, no pressurized cabin, no oxygen supply, no extra windows, steering wheel etc), which means either better performance or more instruments. If unmanned they could even scrap a lot of the redundant and safety systems, since the cost of failure isn't as large. It just seems stupid to put people in it.

They seem to be claiming its a research project, and they are a non profit (501(c)(3)). They could do more with less money if it was unmanned, so I'm pretty sure they mostly just want an awesome tax free toy to play with. I don't blame them though: it sounds like a really fun project.

Re:Why manned? (0)

Anonymous Coward | about 2 months ago | (#47590561)

Mankind goes into space to explore, to be part of something greater. You just want to drag the stars down and stick them underground, underneath tons of sand and dirt, and label them. You're about as far from the stars as you can get.

Re:Why manned? (0)

Anonymous Coward | about 2 months ago | (#47591693)

What can you explore in person in space? Given that the Galaxy is 100,000 light years across, what can you achieve by going 0.1 planetary radii up? You're not any closer, and our ground telescopes can see more, and our unmanned space telescopes see even more.

So what are you exploring?

Re:Why manned? (0)

Anonymous Coward | about 2 months ago | (#47593203)

So what are you exploring?/quote The feasibility of flying in a really thin atmosphere.

Re:Why manned? (1)

Anonymous Coward | about 2 months ago | (#47593247)

But that isn't space, you're still in the Earth's atmosphere. Why not just call it "Aeronautics" and stop invoking all the emotional space bullshit? And you don't need a person in there either.

Re:Why manned? (1)

ihtoit (3393327) | about 2 months ago | (#47590573)

maybe they want controllable to the point of a safely retrievable and significant (by mass, not necessarily nature) payload? 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. 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.

Re:Why manned? (1, Insightful)

Anonymous Coward | about 2 months ago | (#47590701)

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.

Re:Why manned? (1)

plover (150551) | about 2 months ago | (#47591501)

Why manned? Because the record they are planning to break is for manned wing-borne flight. Atmospheric flights capable of carrying people and food have been limited by the need to carry fuel. Unmanned aircraft can already run indefinitely on solar power, but don't have the lift capacity to carry passengers and all the supplies they need.

Higher Construct (0)

Anonymous Coward | about 2 months ago | (#47591913)

To heck with flying higher than ever before, they are going to _construct_ a plane higher than ever before.

"and designed to fly near transonic speed" (1)

Viol8 (599362) | about 2 months ago | (#47592631)

Err , how exactly do they plan on getting to those speeds? Sure , you could get to those speeds in a dive but to do a dive you've got to get up that high in the first place which requires already going at those speeds. Catch 22. And the air currents sure as hell won't be strong enough to do it so unless they plan on having an SR-71 tow them up there I don't see this happening.

Re:"and designed to fly near transonic speed" (1)

drerwk (695572) | about 2 months ago | (#47593219)

The lift produced by a wing is partly a function of the rate of air mass that passes over the wing. Keeping density constant an increase in velocity will increase lift. If the density of the air decreases, as it does with altitude, then one must increase velocity to get the same air mass to pass over the wing and generate the same lift. At the altitude they will be flying, they may well have to fly near the speed of sound to get enough air over the wing to provide sufficient lift. The higher they go, the higher their stall speed so they end up flying in a decreasing envelope between speed of sound and stall. The typical airspeed indicator is a static ram pressure transducer, which is also dependent on the mass of air impinging on it, so it will indicate 'normal' stall and flying speed even though the plane is going much faster.

Re:"and designed to fly near transonic speed" (0)

Anonymous Coward | about 2 months ago | (#47593965)

And the air currents sure as hell won't be strong enough to do it so unless they plan on having an SR-71 tow them up there I don't see this happening.

Glider flight instructor here. Also this glider pilot has been up to 23,000 feet in wave lift over West Virginia. Do yourself a favor and read the wikipedia article on wave, http://en.wikipedia.org/wiki/Lee_Wave . SR-71 aerotow is not necessary for high altitude wave flying. Only the right type of meteorological conditions. Argentina is ideal for this type of soaring.

Re:"and designed to fly near transonic speed" (0)

Anonymous Coward | about 2 months ago | (#47633157)

Another expert asshole that doesn't know the basics of the topic but feels equipped to criticize. FFS. I've seen a quoted gliding speed of 0.5 Mach and a 36:1 glide ratio. So the rate of decent at that speed is 800 fpm. If the vertical speed of the rising air is higher than that, they can climb.

Ambiguity (0)

Anonymous Coward | about 2 months ago | (#47592863)

90000 foot is not 27000 meter
50671 foot is not 15400 meter
This record has an ambiguity to its winning condition.

WHAT ABOUT THE EXCELSIOR III ? (0)

Anonymous Coward | about 2 months ago | (#47594149)

The Excelsior III was a small craft suspended by a high altitude balloon that took one man up to 75 + miles above the Earth before he did his record setting free fall . He wouldve gone higher had there not been a hole in the glove of his pressure suit. Maybe we should use balloons AND rockets to get our guys into space.

Re:WHAT ABOUT THE EXCELSIOR III ? (1)

Anonymous Coward | about 2 months ago | (#47594877)

Excelsior III didn't go above 75 miles, it didn't even reach 20 miles, and stopped at just under 121000 ft. The highest records for unmanned balloons don't even reach half of 75 miles.
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