Quote from: Rocket Science on 06/10/2012 12:27 amLifting Body Air and Spacecraft Q & AWith all the interest generated by Dream Chaser and its direct ancestor the HL-20 and all the other lifting body vehicles, I created this thread to discuss, inform and exchange general questions, ideas and answers as to what exactly a Lifting Body is. This is to keep the Dream Chaser threads clean and without clutter and OT topics as things get busier now. http://forum.nasaspaceflight.com/index.php?topic=29126.msg914401;topicseen#newMay I suggest you change this thread to say the thread linked below? Chris created this thread and at first read it sounded like you were chastising us for posts we have made immediately above. I had figured out what you meant and deleted the post you quoted before you finished your reply.
Lifting Body Air and Spacecraft Q & AWith all the interest generated by Dream Chaser and its direct ancestor the HL-20 and all the other lifting body vehicles, I created this thread to discuss, inform and exchange general questions, ideas and answers as to what exactly a Lifting Body is. This is to keep the Dream Chaser threads clean and without clutter and OT topics as things get busier now. http://forum.nasaspaceflight.com/index.php?topic=29126.msg914401;topicseen#new
Quote from: TomH on 06/10/2012 12:23 amIt is a stretch for me to believe that use of port and starboard brakes to steer caused any problem on STS. Hey, I'm just passing on what that NASA web site I linked to said - take it up with them.Noel
It is a stretch for me to believe that use of port and starboard brakes to steer caused any problem on STS.
Quote from: jnc on 06/10/2012 12:53 amQuote from: TomH on 06/10/2012 12:23 amIt is a stretch for me to believe that use of port and starboard brakes to steer caused any problem on STS. Hey, I'm just passing on what that NASA web site I linked to said - take it up with them.NoelAre you sure you read it all correctly and did you read and understand the entirity of my post above? I am not certain, but I wonder if the changes involved making the nose wheel able to free pivot or making it actively steerable from the stick. There is a huge difference. Taking a non-steerable wheel and making it steerable would involve a lot of hydraulic re-plumbing as well as add excessive weight, an ability and mass that are completely unnecessary. You posted it; I'm not "taking it up with you" so to speak, but rather discussing a concept that you introduced.
I wonder if the changes involved making the nose wheel able to free pivot or making it actively steerable from the stick. There is a huge difference.
I hope the landings are nice and smooth.This is the ace Dream Chaser holds.After long duration Mars simulations on orbit astronauts might need a comfortable touchdown and getting the right medical staff and other support crews to a remote locations / splashdown sites could prove costly in the long run.I like that SNC works with Boeing, don't know exactly how. Something to do with the flight controls and simulator?The stuff with the university students didn't go unnoticed either.I think the good will that's been generated in such a short time really increases the chances of Dream Chaser becoming a reality.Can't wait to see free flight and landing.This is the big intangible draw card DC has. It will be a poster child. Something to put in the presentations and show to the public. Surely we've all heard the "capsules are boring" lines from those less enthused by the space program. Any support that NASA can get is worth going for.
Quote from: TomH on 06/10/2012 01:01 amI wonder if the changes involved making the nose wheel able to free pivot or making it actively steerable from the stick. There is a huge difference.From the NASA page:"because the nose gear had only a single strain control system, shuttle pilots were reluctant to use it at all, preferring differential braking with the main landing gear instead to control the shuttle's rollout down the runway"[Then, after the failure and subsequent investigations...]"The nose wheel was given greater steering authority" (emphasis mine)So, how would you interpret those statements?Noel
Quote from: TomH on 06/10/2012 12:23 amIt is a stretch for me to believe that use of port and starboard brakes to steer caused any problem on STS. It doesn't matter what you believe, differential braking was part of the problems with the brake system, along with orbiter weight growth and axle flexing. Active nose wheel steering was added.
This is the ace Dream Chaser holds.After long duration Mars simulations on orbit astronauts might need a comfortable touchdown and getting the right medical staff and other support crews to a remote locations / splashdown sites could prove costly in the long run.
Active nose wheel steering was added.
Quote from: Jim on 06/10/2012 02:13 amActive nose wheel steering was added.Is that 'nose-wheel steering, previously not present, was added', or 'extra authority was added to that already present'? I ask because the more natural reading of that is the first, but that page I quoted (upthread) said a couple of things (e.g. "nose wheel was given greater steering authority") which imply (to me) that there was some there to start with?Noel
We discussed this before, have a look...
Regarding nose wheel steering, most ground steering (particularly during landing) on any aircraft is done by differential braking to starboard and port wheels.
Quote from: spectre9 on 06/10/2012 01:30 amThis is the ace Dream Chaser holds.After long duration Mars simulations on orbit astronauts might need a comfortable touchdown and getting the right medical staff and other support crews to a remote locations / splashdown sites could prove costly in the long run.Wouldn't an actual Mars return likely hold the possibility of an even more difficult return? Fatigue, possible injuries sustained on the Martian surface. DC would not be available then, only Orion (possibly an advanced Dragon). AFAIK, DC's TPS cannot dissipate any heat greater than that generated by LEO return. I would think it better to practice long duration returns in the same craft that will actually be used on a real Mars return.
Is the mission for Dream Chaser in any way not tied into the ISS?Off topic to discuss it's one and only destination? C'mon mate, leave it to the mods.If the soft landings provided by DC can't be applied to the ISS mission that feature can't be used as an advantage over the competition.This needs to be defined.