re proton centaur in article apr lmpsbbs comm mot com dennisn ecs comm mot com dennis newkirk writes in article apr zeus calpoly edu jgreen trumpet calpoly edu james thomas green writes has anyone looked into the possiblity of a proton centaur combo what would be the benefits and problems with such a combo other than the obvious instability in the xssr now the centaur for the altas is about meters dia and the proton is so that s a good fit for their existing upper stage the block d which sets inside a shround just under meters dia i don t know about launch loads etc but since the centaur survives titan launches which are probably worse than the proton those titan srb s probably shake things up pretty good it seems feasible except the centaur is a very fragile thing and may require integration on the pad which is not available now protons are assembled and transported horizontially does anyone know how much stress in the way of a payload a centaur could support while bolted to a proton horizontally and then taken down the rail road track and erected on the pad the centaur that is being built for t would be a better bet to integrate onto the proton as the t centaur is designed for the extremely harsh envorinment of the t launch it is also closer to m in diameter you ve hit on the real kicker however the centaur is pressure stabilized it cannot hold up its own weight without pressure in the tanks additionally the pressure difference between the two tanks must be maintained to psi that is rather tight to be rocking and rolling on the train the pressure stabilization is how centaur achieves the performance on numerous occasions when i was there the af wanted to see what it would take to make a non pressure stabilized centaur the answer a centaur not worth launching the atlas centaur does not require on pad integration however the t centaur does i believe the on pad integration is to a great extent due to the cleanliness requirements and pfl configuration so maybe something can be done there they would also need lox and lh facilities added to the proton pads unless the new proton second stage is actually built and of course any centaur support systems and facilities no doubt imported from the us at great cost these systems may viloate us law so there are political problems to solve in addition to the instabilities in the cis you mention the addition of lox lh facilities is critical as the centaur tops off as it lifts off a lhe facility is also needed i don t know what the proton uses for fuel but since they are derived from icbm s i would suspect that they use storable propellants which don t have the ullage problem that cryo s do if there is no cryo at the sight at all the addition of these systems could be big not to mention the real tech transfer issues involved with providing centaur gse to russia that issue alone might be enough to kill this idea h d stevens stanford university email hdsteven sun valley stanford edu aerospace robotics laboratory phone lab durand building bullpen stanford ca fax
