SpaceX Grasshopper Launch Filmed From Drone Helicopter

garymortimer writes "SpaceX's Grasshopper flew 325 m (1066 feet) – higher than Manhattan's Chrysler Building – before smoothly landing back on the pad. For the first time in this test, Grasshopper made use of its full navigation sensor suite with the F9-R closed loop control flight algorithms to accomplish a precision landing. Most rockets are equipped with sensors to determine position, but these sensors are generally not accurate enough to accomplish the type of precision landing necessary with Grasshopper."

Comments

a few VTOVL predecessors

[Trepidity]

If you're interested in this kind of thing, there are a few videos of tests of similar vehicles from the 1990s, in both the U.S. and Japan. But they never got funding to produce production versions.

Links:

McDonnell Douglas DC-X

Japan Space Agency RVT

The DC-X still holds the record for the highest flight by a VTOVL rocket, though Space-X plans to challenge that record in a future test.

Re: a few VTOVL predecessors

[FatLittleMonkey]

Don't forget about the landing fuel you have to tote with you along your whole trip. That is not trivial weight.

Actually it is trivial. The rocket is landing almost empty, the extra fuel to get down is vastly less than the amount to go up.

There were industry studies in the '90s and early 2000s that showed fairly conclusively that the added mass of fuel (especially as rockets are never burned dry) is about the same as all the added mass and complexity from a soft-landing parachute system. (Hard landing parachutes are lighter, but not suitable for a reusable system.) Remember, most of your mass is engines and their controllers, pumps, tanks, etc, which you have to carry anyway. And with first stages (which is what Grasshopper is), you can add more fuel without affecting your payload mass. (Reusable upper stages will eat into payload mass.)

[The extra mass required for a horizontal landing, otoh, massively outweighs the small amount extra fuel required for VTOL. They aren't even in the same universe.]

Elon does it again

[wjcofkc]

Elon Musk, with his money, and business genius, in combination with overall nerdiness, is bent on dragging us kicking and screaming into the long overdue sci-fi future we have all been been impatiently waiting for and desperately dreaming of. The rapid progress his technology companies are achieving is nothing short of breathtaking. He pushes limits so far, and so hard, that those nearly impossible limits have been powerless to push back. I for one have no problem with this. I believe Elon Musk will take his place among the most important and well recognized figures in history. We should all feel very lucky to have him.

Re:Reusable lauching craft

[bill_mcgonigle]

My biggest concern here is that the complexity may be the downfall. Historically, the cost of the increase in complexity of reusable rocket designs outpaced the value of returning the hardware.

But then they tried the Shuttle to reduce costs below that of rockets (hey, it looked good on papers with politically dictated calculations). Consider the complexity of *that* solution, especially the make-work landings at Edwards!

SpaceX has no motivation other than to deliver rocketry services to its internal and external customers at the most cost-effective price. It would be extraordinary if they hadn't considered the lifecycle costs.