In article <1sp513$beo@hsc.usc.edu> khayash@hsc.usc.edu (Ken Hayashida) writes:  >Well, Spenz...what can I say? 8-) >You've attacked my beloved vehicle! ;-)  If I may offer a constructive criticism, perhaps you should decide if you love vehicles or the use they are put to. I, myself, think the F-86 is a beautiful aircraft, but rest assured, I wouldn't even think of flying it in combat today. Most of us want access to space and judge vehicles on how they perform.  >We see "zero-defects operation" in many area|s of life.    Not to this degree.  >Calling shuttle flight characteristics *bizarre* in the same post  >as touting DC-X is interesting.    Why?  >DC-X will also have similar "zero-defects" issues (am I wrong?).    Your wrong. The DC approach is very tollerent of failure. It also has the advantage of far greater reliability do to its reusable nature (Shuttle isn't reusable, it's salvagable).  >I am thinking of how DC-X will deploy a chute or reverse orientation at  >supersonic speeds.    The flip over happens at a very low speed, not supersonic. If the DC-X shows the flip over works, it will work unless the laws of physics change.  >How much in DC-X is redundant?  That's the real question.  The final DC-1 will have fully intact abort throughout the entire flight envelop. Upon re-entry for example, it can loose about 80% of available thrust and still land safely.  >Everything we do in life has zero-defects issues at times (agree?).  Everything can suffer from catastrophic failure but that's not the same thing. Shuttle simply isn't a fault tolerent design, SSTO is.  >As a doctor, I can not error in my diagnosis and treatment recommendations.    You don't put your patients in conditions where there is no way out. You wouldn't for example, give a patient a drug and not monitor them for harmful side effects would you?  >While DC-X's R&D program makes good sense, I am less optimistic about DC-X  >as you (and apparently others) are.    You are very much in the minority. If the DC series fails to make orbit, it will still be a very worthwhile effort. It will show us EXACTLY what we do need to do to build SSTO.  >But, DC-X will still have failures.  It is the nature of aerospace R&D.    Again, refering to the DC-1, it will provide fully intact abort theroughout the flight envelop. Shuttle doesn't. DC is fault tollerent, Shuttle isn't.  >It's successors are not slated to be passenger carrying.    Not true. Build a passenger pallet (a fairly easy thing to do) and it will carry passengers.  >The impression I had >when I visited MacDac Huntington Beach's Open House was that the payload space >was limited and the man-ratable version was decades away.  I would suggest you talk to the DC-X crew themselves. Their original schedule had an operational DC-1 flying in 96.  >Shuttle is the only method in the free world of orbiting large life sciences >and medical related packages.  As for now, it is our only ticket into space  >and has my support.  Your ignoring the dammage it does. Mannes space has a reputation for being unreliable and hugely expensive. Shuttle supporters only make it easy for opponents of manned space to kill it.  >You could change my view on DC-X if you could prove the following:  The only way to prove those things is to build it.    Allen