"Frickin' Fantastic" Launch of NASA's Ares I-X Rocket

coondoggie writes "With a hiss and roar, NASA's Ares I-X rocket blasted into the atmosphere this morning at about 11:33 am EST, taking with it a variety of test equipment and sensors but also high hopes for the future of the US space agency. The short test flight — about 2 minutes — will provide NASA an early opportunity to look at hardware, models, facilities and ground operations associated with the mostly new Ares I launch vehicle. The mission went off without a hitch — 'frickin' fantastic' was how one NASA executive classified it on NASA TV — as the upper stage simulator and first stage separated at approximately 130,000 feet over the Atlantic Ocean. The unpowered simulator splashed down in the ocean."

Comments

Did it really go ok?

[Mordstrom]

I am just glad I was not riding in that simulator. Did anyone else notice the separation, and the flight path of the (in the future to be occupied) simulator? The booster and the simulator appeared to tumble after separation. It could have been the camera angle I suppose, but that front section should have continued on, correct?

Re:Did it really go ok?

[Goldenhawk]

I'm an aerospace engineer - I work on planes, but the concepts are familiar and common.

The upper stage DID tumble immediately. The other three aerospace engineers and test pilots watching with me also immediately said "That didn't look right."

The high-zoom ground tracking camera and onboard cameras showed it much better during the replays, where it's clear the separation wasn't as clean as it should have been. But it did not look like the stages hit each other.

It appeared that not all eight of the retro-rockets fired. They were designed to slow the first stage enough to separate the two stages, before the "tumble rockets" fired. From the footage, the retro-rocket flame is visibly asymmetrical. It appeared that only a few of the retro-rockets fired on one side of the aft skirt fairing. As a result, I suspect that the initial separation was not purely fore-aft, but included a healthy rotational component which nudged the second "dummy" stage in a similar slow tumble.

Some comments on this board say "no worries"; the second stage was just an unpowered dummy mass, and the tumble would have been stopped by the final design's engine. Not completely true. They need a clean, non-rotational separation before the second stage engine fires and can fully stabilize the flight path. So the tumble will DEFINITELY concern the engineers.

Finally, don't worry too much about the onboard cameras cutting in and out. Speaking from personal experience in the flight test industry, telemetry is no trivial matter, and downlinking gigabits/sec of data and video is no small feat. Minor mis-alignments in antenna angle can cause momentary signal dropout. Strong jolts (stage burnout, etc.) can also jostle wiring and cause interruptions.

Despite this tumble, the flight appeared to be overall a great success. As the launch director noted to his crew shortly after the flight, the only real delays on the first launch of a very complicated test vehicle were weather-induced (plus the small matter of a fabric probe cover sock that snagged on something yesterday). All in all, I'm quite impressed.

What happened during stage separation?

[bill_mcgonigle]

I was watching the launch with my kids on NASATV, and just when the stages separated, the leading stage started to tumble, and NASATV went black. When they came back in 20 seconds or so, they were following the larger stage on its descent.

I have to say, the supersonic vapor plume around the rocket during acceleration was awesome. I said to my kids, "look, they just broke the sound barrier," and the announcer came on with "passing Mach 1".

Very cool looking rocket, more narrow exhaust plume than I'm used to seeing, interesting angled ascent (it didn't go up straight vertically like a shuttle). We like to rag on NASA, but if this is really a an under-3-year project, who am I to cast stones?