> >Quantity, yeah :) Just yesterday we consolidated five alcohol drums >that each had a few gallons remaining, so I guess it's time to order >more to get the drum deposits back. I look at the row of drums and get >a warm fuzzy feeling from the experience we've accumulated on the 400 >lbf engines- over 450 runs, almost 90 minutes of run time, about 4 tons >of propellants burned. We have almost as much time on the 400 lb >engines as on the 15 lb teacart engine- those twin 2-1/2 minute firings >add up!
You are running ahead of us, but not too much. We are on our fifth drum of peroxide now. >Incidentally, the EZ-Rocket with both engines going is a high S-1400 >system; modest thrust but long duration. The propellant cost are about >equal to the labor cost of maintaining and operating the aircraft. Shouldn't dual 400 lbf engines be a total of 3500 N thrust? Our heaviest lander flights use 100 pounds of peroxide at an Isp of around 100, giving 45,000 NS of thrust. Maximum thrust is 700 lbf / 3100 N, but average is less when hovering. John Carmack _______________________________________________ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/mailman/listinfo/erps-list
