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Solar Powered Helios Plane Destroyed in Test Flight
deglr6328 writes "NASA's solar powered Helios airplane has crashed into the Pacific off the coast of Kauai today during its first test using a regenerative fuel cell power supply. Helios held the record for highest prop propelled plane altitude at 96,863 (set 2 years ago) and was making preparations for a 96 hour continuous flight using its 62,000 solar cells during the day while electrolyzing water into hydrogen and oxygen for use in its fuel cells at night. With the capability to carry 200 lb. to near 100,000 ft. for months on end, Helios was eyed with great anticipation by scientists and RF telecommunications buisnesses alike."
Thus continuing a great tradition of first flights.
If it does not crash and burn it was not a good test.
Ceci n'est pas une signature
...Icarus.
I'm actually rather curious about how it is (er, was) constructed. It looks quite flimsy...
Appropriate name too.
Anyhoo, it's sad to see such a technological marvel crash into the pacific ocean like it did. Maybe NASA will scoop up the wreckage, figure out what went wrong, and then build another one. It would be great to see what we can learn from Helios in general, and not just on an aviation or RF use either. I mean in the field of solar electric generation, and how even in the Aerospace industry it has it's benefits and drawbacks. I personally would love to be using solar electricity instead of having to pay the electric company, but alas, we can't always get what we want...
KevX45
"Now there's a look in your eyes, like black holes in the sky"-Pink Floyd
...because our history is full of science which worked as expected from the start. If it's too complicated to get right the first time, it's not worth doing. Failure depresses people, so only fund guaranteed successes. It's obvious, isn't it?
Yet another example of the dangers of solar power.
If God intended for us to use solar airplanes He would never have given us Jet A.
Eve Fairbanks says I drive a hybrid!LOL
All in the name of science after all. Good thing whatever went wrong happened in the prototype phase, before anything but monetary anticipations were relying on it.
I'm very interested to know exactly what went wrong. From what I briefly read, I'd imagine it was the actual construction which had a problem, not the technology. Unless this was a pre-flight damaged part, this could be valuable information as I'm sure this plane used the latest designs, as other planes will be using.
Man, do I feel bad for that NASA investigation team. Having to spend a large amount of time on the beautiful, garden island of Kaua'i, with its sunny south shore, and lush, tropic north short (with some incredible surfing), not to mention Mt Wai'ale'ale, where it rains 360 days a year and has vegetation that grows no-where else, and the breath-taking Napali cliffs...
I don't envy them.
Wait, yes I do!
In the future, I would want to not be isolated from my friends in the Space Station.
Not trial and success. There's a reason for that.
The odd 747 full of paying commercial passengers has been known to fall out of the sky as well.
You pick up the pieces, figure out what went wrong, start over and hope to do better next time.
Those who refuse to fail will never achieve any measure of success.
KFG
This is why I went into software instead of Engineering. When my program fails, I reboot / recompile / restore the drive ... whatever.
I bet a lot of mechanical engineers wish they had a restart button.
Putting aside the fubar'd aerodynamics of having a hole in the wing (which I think would be significant), I don't think the nitrogen could offset the friction.
liquid n2 is a couple of hundred degrees below zero, but the plasma that it would have to fight is several thousand degrees. I doubt that the shuttle could carry enough n2 to do the job.
Not to mention that you'd have to have a massive amount of pipes, etc... note really feasible.
"Faith: Belief without evidence in what is told by one who speaks without knowledge, of things without parallel." - A.B.
Two thoughts. First, this is unfortunate, but it is what happens when you push the boundaries. It isn't safe on the cutting edge.
Second, if we want more funding for an agency then a strong case for it must be made. We shouldn't fund NASA just because it is NASA. NASA has done a poor job of creating a vision for what can and should do. It isn't clear to me why they should continue at current budget levels. I wonder if part of the reason is that it has become a government agency that is more focused on sustaining itself then offering a service to the people it serves.
The remotely piloted, one-of-a-kind Helios Prototype crashed off Kauai within the testing area of the Navy's Pacific Missile Range Facility
Maybe flying it in a missile test range wasn't such a good idea...
Life is short: void the warranty.
The National Simian Safety Board has permanently suspended travel to the big flat thing under the trees after two terranauts were killed by a lion. A local citizens group protested the allocation of bananas to ground exploration, saying that the bananas would be better spent on grooming and bug removal.
Mea navis aericumbens anguillis abundat
I think it's time to reconsider the validity of spending billions on disaster after disaster when so much needs to be taken care of at home.
Ok, let me get this straight. You list some of NASA's failures and ignore all of its successes, and conclude from that analysis that NASA is a big waste of time and money? Hmm...
NASA's budget is 14 GigaUSD per year. Bush's innefectual, for-the-wealthy tax cut is 35 GigaUSD per year. If your true interest is taking care of problems at home like war and famine, you should be attacking the Bush administration, not NASA.
Liberal (adj.): Free from bigotry; open to progress; tolerant of others.
Apparently, in your hurry to post this profundity, you missed the article.
"We were flying at about the 8,000-foot altitude west of Kauai over the ocean and the aircraft simply broke up," said Alan Brown, a spokesman for NASA's Dryden Flight Research Center in Edwards, Calif.
It is very flimsy.
http://use.perl.org
Apparently it's going to beat that ~96000 record the Helios set, but won't be officially eligable because it's not going to take off under it's own power.
The balloon that launches it is fairly impressive too:
"As tall as the Empire State Building, their manned envelope will be the biggest ever flown."
During the presentation, someone asked about what the commercial applications were for such technology. Apparently, blimp companies are VERY interested in fuel cell technology. Blimps, as they burn off fuel for the steering engines, get lighter. In order to get back down to the ground, they sometimes have to blow out helium which is VERY expensive. But with a fuel cell, the blimp actually gets heavier as flight goes one because they can hang onto the "exhaust" (water) and keep the blimp in equilibrium through the entire flight.
The military is of course interested too because fuel cell powered planes are VERY quiet (electric motor) and the technolgoy will allow for far greater range than batteries.
-S
--- What parts of "shall make no law", "shall not be infringed", and "shall not be violated" don't you understand?
The thing about flexible wings is that they have to be. So what if the wings bent into a shallow U? The U-2 plane wings did the exact same thing, as well as most glider planes. The bowing of the wings actually comes in handy during turbulence, in that it can flex a little in order to absorb some of the shock instead of simply snaping because the impact of the turbulent air momentarily exceeded the wing's structural tolerances.
Next time you fly in a passanger airplane, sit near the wing and watch it in flight. At first, it may be a little disconcerting to watch the wing flex as it plows through the air, but this kind of structural flexibility is what aids in it's strength.
In science, if you demand perfection, don't expect any advancement.
Feel free to mod me "-1 - Angry Jerk".
Posted AC because I do not have a /. account.
IAARS. (I Am A Rocket Scientist.)
One question that has plagued me since the destruction of Columbia: If there wouldn't have been extreme heat going into the wing, would the crew still be alive? I'm no aerodynamics expert, but isn't it possible, at the point of entry into the atmosphere, when temperatures start to rise, that the shuttle release some liquid nitrogen or some other super-coolant in some manner as to keep homeostasis of the vehicle?
Upon reentry, the Orbiter (the white and black plane-lookin' portion of the Shuttle), is carrying no cryofuels. They are stored in the large red-orange External Tank, and used up during launch. The Shuttle uses LOX and LH2, both of which are f'nasty to deal with and are economical only to generate the immense thrust necessary to achieve orbit. While in orbit, the Orbiter maneuvers using (relatively) small hydrazine thrusters. N2H4 is also f'nasty, but somewhat less so than either LOX or LH2. NASA's Shuttle Basics website provides a good nontechnical overview of mission stages.
The Orbiter doesn't maintain homeostasis during reentry. The bottom gets really, really, really hot. Because the Orbiter is essentially falling back to Earth, the crew wants to bleed off as much speed as possible. By taking advantage of friction with the air, the Orbiter can slow down, and not be travelling at Mach 20 or so when it lands. It is a tricky balancing act among speed, attitude, and heat--the tiles can only absorb so much thermal energy, the crew has only aerodynamic control of the Orbiter's attitude, and there is a whole lot of kinetic energy that needs somewhere to go.
From my understanding of the physics of reentry, and the information available about the Columbia breakup, I do not think that the only factor was heat. The speeds at which spacecraft travel during reentry are so far beyond the speed of sound that aerodynamicists classify them not as supersonic, but hypersonic. The hypersonic regime (generally > M5) is somewhat counterintuitive. Friction with air generates enough heat at reentry speeds (M20 and up) to vaporize graphite and cause dissociation in N2 and O2 molecules, creating an ion cloud around the spacecraft.
We would not be able to travel at hypersonic speeds if not for a quirk of geometry. If you look at a supersonic vehicle, such as the X-1, you will notice that the leading edges of the wings and fuselage are pointed and form very sharp angles. This causes the shockwave formed by supersonic speed to break cleanly around the vehicle, which is good for aerodynamics. If you look at a hypersonic vehicle, like the Orbiter, you will notice a blunt, rounded leading edge and nosecone, which causes the shockwave to separate from the craft, forming a cushion of air. This insulates the Orbiter somewhat from the heat of reentry.
If that rounded profile is compromised, in Columbia's case by loss of tiles on the leading edge, the shock will break as in a supersonic craft, allowing both heat to transfer to the wing, and also subjecting the Orbiter to the considerable kinetic forces generated by air resistance. Heat did not tear Columbia apart. Her own speed did.
-Carolyn Lachance
I simply can't understand this line of reasoning. Bush cut income, estate, and dividend taxes, targeting the cuts disproportionately at the wealthy investor class. He did not cut payroll taxes. Certainly people who pay payroll taxes are also "PAY[ing] TAXES", are they not? And isn't it true that payroll taxes generate a huge surplus in the social security trust fund, while income taxes don't pay anywhere near enough into the general account to pay for basic governmental services? Are we not running a deficit?
Now you may argue that payroll taxes are collected strictly to pay out social services and are not collected for general revenue or spent on general services, as such they shouldn't be cut. However, this isn't the case. In fact the HUGE SURPLUS of $200B/yr is siphoned off to reduce our general account deficit. In fact, the currently stated $450B (4.5%GDP) deficit would actually be $650B (6.5%GDP) were it not for the surplus generated from payroll taxes. Note that payroll tax collections are capped at $86K/yr, meaning that any income above $86K/yr is not taxed; this is called a regressive tax because collections don't continue linearly across all income streams. The rich pay much less proportionally for payroll taxes than do you or I.
Realize that general revenues pay for basic government services such as the military, infrastructure (roads, bridges, airports, rail, etc), NASA, and government overhead - NOT social services. So, I wonder how anyone can defend a tax cut that reduces revenue from a general account which is already $650B/yr in deficit? And the gall of claiming that it is done on the grounds that income taxes are somehow 'real' while payroll taxes don't matter, when it is the payroll tax surplus which covers 1/3rd of our current account deficit.
Whatever you may think of the rationality of providing social services (I support them, you may not, either opinion is legitimate political debate), certainly you agree that general services slated for payment through income taxes should collect enough on their own to pay for those services. We should not be running a 6.5% GDP deficit (or even a 4.5% GDP deficit) while at the same time cutting the very taxes slated to pay for those services. That the current administration claims to cut these taxes for the people who "PAY TAXES", while at the same time cutting no taxes for those who pay a regressive tax, is simply disingenuous and offensive.
And I haven't even begun discussing our current foreign trade deficit, which is another +5% of GDP. Frankly, if this continues Bush's administration may well take America over the brink into bankruptcy. We're already printing money to prevent 'deflation', the Treasury Department has signaled it's willingness to let the dollar continue to depreciate in value against other foreign currencies, and our manufacturing base is running 1/4 idle.
IMO, these tax cuts are a policy mess. Bush and the fed are 'pushing on a string' with their policy blunders by flooding the investment streets with money while there's nothing left to invest in. We should be pushing the money down to the individual low income tax payers to stir consumption, not further investment and development with no buyers in sight.
Cheers,
--Maynard
>IAARS. (I Am A Rocket Scientist.) ...
>
>The Shuttle uses LOX and LH2, both of which are f'nasty to deal with and are economical only to
>generate the immense thrust necessary to achieve orbit. While in orbit, the Orbiter maneuvers
>using (relatively) small hydrazine thrusters. N2H4 is also f'nasty, but somewhat less so than
>either LOX or LH2.
???
The OMS uses hydrazine / nitrogen tetroxide, which is way, WAY more nasty than LOX / LH2.
LOX / LH2 are cryogens, and contact with them will give you frostbite. Hydrazine is carcinogenic and toxic, but nitrogen tetroxide is roughly as poisonous as the best war gasses from WWI. Plus, it has very low surface tension, so when it spills, it spreads extremely rapidly, which causes it to vaporize even faster than the already high vapor pressure would indicate. The various oxides of nitrogen are famous for the "BFRC" ( big red cloud ) that results from spills, which you should run away from very fast.
John Carmack