SpaceX Falcon 9 Reusable Flies with Fins
Video: SpaceX Falcon F9R 1000m Flight, SpaceRef Business
“SpaceX has released this video of Falcon 9 Reusable (F9R) during a 1000m test flight at their rocket development facility in McGregor, TX and was their first test that included a set of steerable fins that provide control of the rocket during the fly back portion of return.”
Interesting how we chose to portray things. Your headline: positive. If this had been a NASA flight national headline: NASA puts heard of cattle in peril to test risky space system. <g> An aside, the cows seemed pretty OK. Wonder what they were thinking.
The headline is neutral IMHO.
With all those cattle, they had to attach fly swatters to the F9R. 😉
Well played!
They needed four of those big suckers, and they were put to good use on the descent (must have hit a swarm)
Elon is clearly working on the Herd Shot ‘Round The World. 😉
NASA would never risk momentarily frightening cattle.
NASA hasn’t done anything positive in years. It’s not that NASAWatch is anti-NASA, the fact is NASA deserves nothing but criticism. And not so much because of Congress (or even NASA HQ) as others imply here, but because NASA itself is rotten from within at the field center level and is no longer capable of accomplishing things worth praise. Even our big event this year, the EFT-1 flight of Orion, is 8 months behind schedule. It won’t accomplish anything that can’t be done by analysis. The thing has been in development for 10 years and it will be nothing but a shell of the capsule with minimal systems. It’s a pathetic joke that 10 years and $12 billion into developing a capsule that this is all we can do.
I’m more excited by SpaceX CRS missions and its first stage recovery attempts than NASA’s Orion mock-up test flight. Sad reflection of how American HSF is at an all-time nadir.
Me too, and I work for NASA. It is sad to witness the decline and be helpless to reverse it. Technical competence is not just under-valued, it is despised because it is contrary to the political ambitions of “leadership.”
I guess I had imagined the steering fins would be more traditional, as opposed to the eggcrate-like paddles. Is that how they’re done now, or is that a SpaceX thing??
grid fins aren’t new, but they are uncommon. the most well known use of them is as part of the Soyuz LAS.
they were also used on Soviet missiles and ICBMs, though most recently some US bombs have used them.
they provide superior control in supersonic flight, act as drag fins in transsonic flight (this will actually be beneficial to the rocket stage since it needs to slow down) and provide just as good control as traditional fins in subsonic flight.
see this page for an excellent overview of what grid fins are and how they work.
http://www.aerospaceweb.org…
Well here’s a thought…if they “lost it” Elon could have always retorted…
“Let them eat steak!”
🙂
I find your ability to equate American New Space entrepreneurship, with 18th Century French political history, udderly moooving.
(pass the A-1)
There they go again stealing ideas from real rocket Scientists. This time from THE rocket man . Didn’t Robert first use a system of small turning vanes before he invented the gimbaling rocket motor??? I wish Spacex would be more original!
“You’re so vane, you probably think this launch is about you, you’re so vane….” 😉
Von Braun’s Redstone missile, in addition to fins at its base, had 4 small, wedge shaped steerable fins at the bottom of the large warhead section, for final guidance of the re-entering warhead.
the more i think about it, the more these grid fins make sense. the first stage will still need the RCS thrusters for maneuvering at high altitudes after stage separation, but the fins can be deployed shortly after the burn back to the launch site. grid fins are great for maneuvering at supersonic speeds and subsonic speeds, but are essentially drag flaps in the transsonic regime – so they will be useful for decelerating the stage through transsonic speeds while maintaining the orientation of the stage.
see this page for an excellent overview of what grid fins are and how they work.
http://www.aerospaceweb.org…
they save RCS fuel during unpowered flight, solve the roll control problem encountered in the first post-launch testing, and provide additional maneuvering capability for a controlled return to the launch site. While SpaceX has demonstrated they can do these things without the fins, they do provide additional capabilities that simplify the return to the launch site process.
I figured this addition was probably the result of a trade study that found the fins provide more control authority during more of the flyback trajectory than would an equal or greater mass of RCS fuel. There’s also the belt-and-suspenders aspect of having two ways to accomplish a job – vehicle stability and attitude control – that can back each other up.
If NASA did a test this successful, this publicly, the subtitle would be: “Congress outraged at brazen success: Plans emergency session to cancel program.”
When I first saw those fins, they reminded me of the larger speed brake version on the Soyuz manned rocket. I wonder if these are large enough the use in a similar manner, on the manned Falcon 9 / Dragon, to slow the stack a little, so the Dragon has a little more margin to get away from a mishap?
grid fins are great for maneuvering at supersonic speeds and subsonic speeds, but are essentially drag flaps in the transsonic regime – so they will be useful for decelerating the stage through transsonic speeds while maintaining the orientation of the stage.
see this page for an excellent overview of what grid fins are and how they work.
http://www.aerospaceweb.org…