no worries.. Actually, I appreciate the second opinion on my math. Thanks too for the additional details. If you don’t mind me asking... to confirm regarding Norman's observation are your fuel/ox jets deliberately not impinging directly upon each other in the chamber? If so is the GOX line slightly further upstream of the fuel (or vice versa)? I think I had missed that point when I originally read the description of your design. On Sunday, September 21, 2014 10:49 PM, Robert Watzlavick <rocket@xxxxxxxxxxxxxx> wrote: Oops - I made a mistake. I thought your last run was 0.01 lbm/s but it is 0.01 kg/s (0.022 lbm/s) which is right in the ballpark. So forget the last paragraph. -Bob