Boeing CST-100 One Step Closer
Boeing Completes New Spacecraft, Rocket Milestones, NASA
“The Boeing Company of Houston, a NASA Commercial Crew Program (CCP) partner, recently performed wind tunnel testing of its CST-100 spacecraft and integrated launch vehicle, the United Launch Alliance (ULA) Atlas V rocket.”
“… Boeing now has completed two of eight performance milestones under CCiCap and is on track to complete all 19 of its milestones around mid-2014.”
At first glance, just for a brief moment, this photo of the CST-100 and Atlas V sitting horizontally (which I’ve never seen before) reminded me of the Discovery One spacecraft from the movie 2001: A Space Odyssey. It was a silly gestalt, but it was a cool moment. What would have really made it cool (or rather real hot) is if it had included large cooling radiators, indicating a nuclear-powered spacecraft.
A question for the pros out there: given the dynamic pressures involved and the density of our atmosphere, how useful are scale-model wind tunnel tests like this. Theoretically (within my very limited experience in this field) turbulence, vibration, laminar flow, etc. characteristics could be very different at full scale from what this testing will show. And I would expect the interdependencies and trade-offs between issues to be different at full scale as well. Is this a possibility or am I worried about nothing?
> “how useful are scale-model wind tunnel tests like this.”
Very useful as random turbulence and flow separation are still very difficult to model with CFD. Not that a wind tunnel test will model exactly match full scale flow but can help determine where shockwaves will occur and what magnitude. And will provide experimental data on aero loads. Rocket development is expensive and afters years of work, at least spend a little on wind tunnel test to evaluate design and be sure of no surprises.
Nice to see that the different diameters are not a problem. The 60 day report says that Spacex will use mock ups for the pad abort, not a finished, ready to launch system. What ever NASA wants to do is fine. As long as it heads for ocean and deploys the parachutes, that is the test. Since the thruster failure of the last Dragon,caused by parts supplier change, would it be better to re-use a Dragon? Why does NASA use a new one each time? Because that is the way Apollo was done? Will there be a new spacecraft each time for crew? All say they are reusable.
Steve:There is a lot history of models to full scale. I don’t think you have to worry.
Tinker said once that the idea is to have NASA/tax payer money help commercial space bt building up a fleet dragons. Sure helps Spacex. SPACEX owns the dragons AFTER each flight right??? In return we get spacex with more to spend on R and D like grasshipper right????
Thanks S13. What actually got me thinking about this was the wind tunnel tests for the MSL (Curiosity) landing. They had intermittent parachute tangling that they couldn’t explain and couldn’t reproduce on demand. The problem turned out to be caused by the fact that they were wind tunnel testing a horizontal package to investigate a situation which actually pertained to a vertical package in the real world (gravity effects were rotated 90 degrees in the tests). Earlier on, some engineers were also questioning whether along-skin air flows were the same as reality for scale model test articles.
I always assumed NASA’s new-only rule was simply because they didn’t want to bother with flight testing, reviewing, and certifying that a reused Dragon is reliable. Which is fine, it just means SpaceX can use them for non-NASA purposes.
My thinking on that is that all the Dragon’s that have flown did not have any of the new thruster package installed — not just the thrusters but all the associated plumbing and tanks. I would imagine that they are not retro-fittable.
Its great to see that the US has the capability to develop a new manned spacecraft and do it on a reasonable and challenging schedule, despite NASA’s shortcomings.
“Why does NASA use a new one each time? Because that is the way Apollo was done? Will there be a new spacecraft each time for crew?”
NASA has not used a new ‘spacecraft’ for every test-at least not to date and not for the foreseeable future. All NASA has done is a series of partial mock-ups. Next year’s orbital flight is also not a complete and real spacecraft; it is only a real crew compartment and a kluged together series of parts that make up the remainder of the vehicle. They are waiting on ESA to supply a service module, maybe in 5-10 years. As long as saltwater penetrates into the spacecraft and they give up 80% of the spacecraft prior to landing, yes, most of every vehicle will be a new one. That is a large part of the mistake that is Orion/MPCV. Its a step backwards. But look at the positive aspect-we are only $ 8 to 10 billion into a tens of billion dollar development effort.
They were going to reuse the 2014 one for an abort test,but I think that has been cancelled. I consider NASA the one that decides if to reuse Dragon. Although SpaceX may have had it in their proposal. They said they were talking to NASA about reuse. The new ones come down on land so no worries about salt water. It seems strange that the one that talks most about reuse did not do it when they had the chance. Russia has a new capsule that is reusable. Maybe the Almaz capsule.
IIRC SpaceX owns the Dragon capsules, and presumably they will reuse them on commercial flights.