A Second Childhood For The Rocketeers
Honolulu HI (SPX) Oct 27, 2006
Those who forget space history are condemned to repeat it - with better video quality... I've been watching video clips from the Wirefly X-Prize Cup at Las Cruces Airport and my reaction is an overpowering sense of deja vu. We've already seen this in cable TV documentaries. We already saw most of the X-Prize Cup events in grainy, silent black and white newsreel footage from Weimar Germany in the 1920s.
The rocket truck is a less stylish version of Fritz Opel's rocket racecars. The Rocket Racing League's rocket airplane is a plastic version of Max Valier's rocket gliders. The rocket bike is the rocket skater adapted to the warmer climate of New Mexico. (The rocket railcar was missing, possibly due to the absence of abandoned railroad tracks in Las Cruces.)
The common element of all these projects, both the Roaring Twenties originals and the Naughty Oughties copies, is that they are spectacular stunts that look good on the screen but have no role in advancing real rocket or space technology.
None of the rocket autos, rocket gliders, rocket backpacks and rocket railcars of the 1920s contributed anything to the German Army's rocket research at Kummersdorf and Peenemunde, which drew its personnel cadre from the staid and newsreel-shy German Rocket Society. The only result of these publicity stunts was the death of Max Valier in a rocket explosion, which gave the Gestapo a convenient excuse to stamp out all private rocketry research.
Similarly, none of the rockets on display at Las Cruces incorporate anything new that could significantly reduce the cost or difficulty of spaceflight. Most of the participants exhibited a level of engineering more characteristic of hobby rocketeers than serious market-oriented businesses.
Some elements of the event were reminiscent of a later Technicolor era of rocketry. The rocket belt was identical to the one James Bond used to escape from SMERSH. The Armadillo Aerospace "lunar lander" Pixel resembled several early VTOL "flying bedstead" test rigs, and its flight profile was identical to early DC-X flights (right down to the flopovers and fires).
This lunar lander competition was the most senseless event at Las Cruces. The strangest thing about it was its sponsorship by NASA and Northrop Grumman. Neither NASA nor Northrop Grumman need any help in designing lunar landers.
Grumman built the original Apollo Lunar Module.
And NASA has the world's most successful planetary landing team in the JPL/Lockheed-Denver collaboration that has repeatedly soft-landed probes on Mars, which is a far more hostile planet than the Moon. Lunar landings don't have the added complications of heat shields, parachutes, and high winds.
Even the hapless Babakin Bureau in the old Soviet Union achieved several totally automated Moon landings in their Luna and Lunokhod programs, and the Korolev Bureau carried out simulated moon landings and launches in LEO with their manned "Lunar Cabin". We already know how to land on the Moon, despite what the X-Cup promoters claim.
Furthermore, test flights of hovering rocket vehicles on Earth are a bad way to simulate a lunar landing. The stronger gravity means that you need 6x more thrust, 6x more fuel, and 6x stronger landing gear than on the Moon. The rocket exhaust throws up more debris and needs stronger control forces to keep it pointing in the right direction. The engine's performance is reduced by atmospheric back pressure.
To avoid these problems, all the craft used for practicing lunar landings on Earth in the 1960s used either a gimbaled turbojet or an overhead crane to offset 5/6 of terrestrial gravity and make the control dynamics approximate reality.
But the whole point of the X-Prize Cup is spectacle rather than research, so these issues were totally ignored. Since the vehicles had to hover on rocket thrust alone, their empty weight had to be drastically cut.
The Pixel vehicle had a ultra-lightweight landing gear placed so as to transfer the landing loads directly to the huge fuel tanks. The landing legs were so short that there was little room for the rocket exhaust bouncing off the ground to escape, so close together that they gave little resistance to tip-over forces, and lacked any footpad to spread the craft's weight over the ground.
Anyone with a lick of engineering sense in their head could see that this design would suffer exactly the sort of accidents that knocked it out of the competition. When I saw pictures of Pixel on the ground I assumed that it wasn't fully assembled yet, and couldn't believe my eyes when they tried to fly it. Apparently Armadillo even planned to use the same inadequate design for the Level 2 competition, which involved landing on irregular unpaved ground!
Every soft lunar lander has used widely spaced landing legs with ample shock absorption and large footpads, and early cutoff of the engines to minimize exhaust reflection and flying dirt. This classic formula is now universally accepted for Mars landers also, after a short disappointing fling with Luna-9 style airbags.
But it seems to be a basic principle of alt.space firms to totally ignore the hard-won engineering experience of old.space and make every piece of hardware as visibly different as possible from what has actually worked in the past. Their mantra seems to be "different is better".
A mitigating factor in the failure of Pixel (and the three teams that registered but didn't participate) was the small size of the prizes offered by NASA. The basic lesson of the Beagle-2, Hayabusa, and Mars Polar Lander failures is that planetary landings can't be done on the cheap. A million-dollar purse will not inspire anyone to make the multi-million dollar investment needed to properly engineer and test a new design of planetary lander - even one using conventional technology.
So I think the only lasting impact of the X-Prize Cup will be another series of humorous video sequences that future documentary producers can use to show how childish and naive we were back in the 21st century. Bids are probably rolling in to X-Prize headquarters from the History Channel right now.
If I were in their shoes, I'd erase all that footage before it appears on our grandchildren's LED-walls and makes them hoot derisively like I did all last weekend.
Jeffrey F. Bell is a former space scientist and recovering pro-space activist.
Lots of Space For Opinion
The Audacity To Dream And The Audacity To Execute
Los Angeles CA (SPX) Oct 27, 2006
On Friday morning October 20th, with the 6am morning dawn light, space professionals and enthusiasts streamed into the Las Cruces Airport in New Mexico for the X-Prize Cup events. There was a special spirit in the air, partly because of the festival like atmosphere, but also because many people recognized this to be part of a larger and more important historical event.
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