re space manuevering tug was hst servicing mission prb access digex net pat writes i wrote prb access digex net pat writes given that what i described for the hst seemed to be the smt has someone actually verified that mass is the predominant constraint on this mission you seem to be assuming it without giving supporting evidence someone from nasa posted that there were very significant mass margins on the hst re boost mission a while back i had asked why not carry the edo pallet up and the answer was the mass margins were tight enough they weren t even carrying extra suits so how much mass is saved by not burning the oms that s the critical question my data shows that the oms engines hold kg of propellant of that a substantial fraction is going to be used for the first oms burn the reentry burn and the reserve so pat tell us how much fuel the altitude change is going to take and how much the edo pallet bus and extra parts are going mass if you can make the numbers work out then i ll be interested after you show us that it can be done then tell us how much the edo pallet bus and extra equipment is going to cost why not do this quick test goldins philosophjy of faster cheaper better build a real fast space tug to handle the re boost of the hst using clean cryo fuels and get it ready before the hst mission pat this would be slower more expensive and worse where s wingo when you need him come on knock that s t off you forget that during skylab they did overnight mission planning for the repair eva s also during thexd intelsat mission they did overnight wetf simulations i somehow think they could train up a new eva in months first while astronauts certainly have done evas with minimal planning that was because they had to they don t like to do that as a general rule second remember why they had to improvise during intelsat they were trying to attach a motor to a piece of hardware that wasn t designed to do that trying to shortcut the training is only going to make a repeat more likely third they don t have eight months they have however much time is left after someone comes up with a plan shows it can work and gets it approved you may think i have a pessimistic attitude i think it s realistic i m not saying that the engineering task is impossible few engineering tasks are what i m saying is that this is neither cost effective nor feasible under nasa management and as for building hardware anything can be built if you want it bad enough you forget the bus is already built all they d ahve to do is soup it up even test it on a delta mission all they have to do is soup it up just what does that mean don t get into this mode of negativism besides at the rate missions slip the discovery won t launch on this mission until march that s almost a year more expensive your proposal still requires the shuttle to do everything it was going to do execpt fire the oms in addition you ve added significant extra cost for a new piece of complex hardware ah but how much more expensive is the second hst servicing mission the second servicing mission is a contingency you have neither shown that it would be necessary without your plan nor that it would be unnecessary with your plan you forget there is a bum fgs the solar array electronics are getting hinky and there is still months until the servicing mission no pat i haven t forgotten if the smt can avoid a second servicing mission that s million saved no pat that s million minus the cost of the new hardware minus the cost of the extra struff you want to bring along minus development and mangement costs minus extra operating costs tanstaafl according to a gao report on the omv i have before me there are only two currently planned missions that could use such a vehicle hst and axaf since axaf has since been scaled back and hst can rely on the shuttle there doesn t seem to be any need for your vehicle of course there wasn t any need for the saturn v after apollo too i m sure that if you reread this you ll see that your argument is falacious as for the problems with the aperture door i am sure they can work out some way to handle that maybe a plug made from frozen ice it ll keep out any contamination yet sublime away after teh boost pat not only is this messy and less reliable than a device that s made to perform this task it also ignores the point there is a desire to have astronauts available so that if the door fails to open something can be done about it unless you can provide a very reliable way of reopening the door you haven t solved the problem josh hopkins jbh uxa cso uiuc edu find a way or make one attributed to hannibal
