re dc x vehicle nears flight test in article c zhkw dn zoo toronto edu henry zoo toronto edu henry spencer writes in article snap paj uk co gec mrc paul johnson writes this bit interests me how much automatic control is there is it purely autonomous or is there some degree of ground control the stick and rudder man is always the onboard computer the computer normally gets its orders from a stored program but they can be overridden from the ground how is the transition from aerodynamic flight if thats what it is to hover accomplished this is the really new part it s also one of the tricky parts there are four different ideas and dc x will probably end up trying all of them this is from talking to mitch burnside clapp who s one of the dc x test pilots at making orbit pop a drogue chute from the nose light the engines once the thing stabilizes base first simple and reliable heavy shock loads on an area of structure that doesn t otherwise carry major loads needs a door in the hot part of the structure a door whose operation is mission critical switch off pitch stability the dc is aerodynamically unstable at subsonic speeds wait for it to flip and catch it at degrees then light engines a bit scary light the engines and use thrust vectoring to push the tail around probably the preferred method in the long run tricky because of the fuel feed plumbing the fuel will start off in the tops of the tanks then slop down to the bottoms during the flip keeping the engines properly fed will be complicated build up speed in a dive then pull up hard losing a lot of speed this thing s l d is not that great until it s headed up and the vertical velocity drops to zero at which point it starts to fall tail first light engines also a bit scary and you probably don t have enough altitude left to try again all work is one man s work henry spencer u of toronto zoology kipling henry zoo toronto edu utzoo henry since the dc x is to take off horizontal why not land that way why do the martian landing thing or am i missing something don t know to much about dc x and such overly obvious why not just fall to earth like the russian crafts parachute in then michael adams nsmca acad alaska edu i m not high just jacked please enlighten me ignorance is easy to correct make a mistake and everyone will let you know you messed up
