<i>".... Prop, any likelihood, do you think, of densified LH2/LOX on either the Delta IV or SDHLV? I've read that they tested an RS-68 with densified propellants and it worked OK...."</i><br /><br />Hi Red, I am not aware of any RS-68 testing with densified propellant. Can you provide links?<br /><br />There have been <i>studies</i> on using densified LH2/LO2 propellant, as well as "cross-feed" (in the case of Heavy configuration), with RS-68 but no actual testing was conducted that I am aware of.<br /><br />NASA has studied the used of densified propellant on the STS but it remained a study. There has not been talks on propellant densification on the SDHLV, but that does not mean it is not an option. <br /><br /> <div class="Discussion_UserSignature"> </div>