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NASA Tests Heaviest Chute Drop Ever
Iddo Genuth writes "NASA and the US Air Force have successfully tested a new super-chute system aimed at reclaiming reusable Ares booster rockets. On February 28, 2009 a 50,000-pound dummy rocket booster was dropped in the Arizona desert and slowed by a system of five parachutes before it crashed to the ground. The booster landed softly without any damage. This was possibly the heaviest parachute drop ever, and NASA is planning to perform even heavier drops of up to 90,000 pounds in the next few months."
Afraid not. Parachutes work by increasing air drag. An incoming asteroid would be moving at something like 30 miles per second. The parachute would only have at most a couple of seconds to work. Having said that, if you had a boundary case of an asteroid that would lose a considerable portion of its energy to the atmosphere, but still have enough to cause significant property damage, then you could attach an inflatable balloon (I believe they call it a "ballute") to the front to increase the cross-sectional area of the asteroid, so it would lose more energy to the upper atmosphere. Those asteroids are probably too infrequent to bother planning for.
But then we wouldn't have known how to build a reusable shuttle, which I'm sure left some residual science in other fields as well.
Some things are worth doing just for the sake of it.
The ones who care already do. In some cases, it is easier to use the empirical system, for example, I can't imagine having to do construction with millimeters, but 1/8 and 1/16 inch are the perfect tolerances of precision when framing a house. The millimeters are just too hard to see because they're so close together. Try it sometime. I guess in Europe they must use them, so it must be doable (or maybe that's why they use bricks so much in construction instead of wood!)
In other cases it's easier to use the SI units, like if you are a scientist trying to calculate the velocity of things falling. People who need to do this already DO use SI units.
Finally, there are times when it doesn't really matter which one you use, like when you are weighing yourself, does it really matter if you use kilograms or pounds? Not really. The effort to change there just isn't worth it for most people. If we talked to Europeans more often, it might be, but.......
Incidentally, it isn't just Americans. Other countries use a mix of measurements as well. For example, in El Salvador, they use centimeters to measure their height, kilograms to measure their weight, and liters to measure their water, and gallons to measure their gas. I believe Taiwan uses some traditional measurements as well.
Qxe4
The shuttle concept in an of itself is not a terrible idea, however it got horribly warped by the Air Force's unrelenting requirements (i.e. payload bay size, etc.) and morphed into something horrendously inefficient.
There are certain parts of rockets that lend themselves much more to re-use than others. In this case, I believe the intent for Ares rockets is to replace the nozzle each flight -- they decided it was cheaper to build consumable thruster nozzles for each flight than to re-process the expensive, intricate cooling designs for keeping a nozzle in good enough shape to use again.
Aikon-
I want to see flyback boosters! There was a design they had for the shuttle boosters that would replace them with liquid-fueled models and they would also come equipped with jet engines. Launches as a liquid-fueled rocket, separates from the shuttle stack, deploys swing wings (which were flush with the airframe at launch) and fire up the conventional jets to make a powered return flight, landing at the Cape pretty as you please.
I think they scrapped this plan because it would be too much development for a program near the end of its life but you'd think it would be viable for the boost stages of newer vehicles. The first stage has got to be the heaviest, most expensive part of the stack. The refurb cost on the shuttle makes you think it might just be cheaper to throw it away but maybe we could actually save some money with better engineering on something like this?
Kwisatz Haderach
Sell the spice to CHOAM
This Mahdi took Shaddam's Throne