Thanks, Mike, for posting the link to Ray Dausman’s story. Although Ray’s book, “Reluctant Rocketman”, is filled with inaccuracies, mostly inconsequential, there are a few that challenge the credibility of The Blue Flame’s achievement and of its sponsor, America’s natural gas industry. In fairness to our generous sponsor, that begs for correction.
Since Ray wasn’t around for the last year of the project, he apparently wasn’t aware of the maximum speed restriction imposed by the Goodyear Tire Company racing department for our first year’s (and only) attempt, 700 miles per hour. The Blue Flame was, however, originally designed with the intent of ultimately comfortably achieving Mach 1 plus, up to 850 miles per hour, with full thrust [22,000 pounds] and a larger LNG fuel tank. That larger LNG tank was never installed in 1970, to ensure compliance with the Goodyear 700 miles per hour mandate. So, we set the record with (figuratively) one arm tied behind our back, and less than 16,000 pounds thrust.
Ray’s first big “revelation” concerned the missing flow control orifice that proportioned the LNG flow between the 2nd and 3rd stage LNG injectors. He claimed we erred by not installing the restrictor orifice. However, since we never intended to operate at full thrust (700 miles per hour speed restriction, remember), we only planned to use the 2nd stage injectors and, therefore, no need to proportionally control the LNG flow. The flow control orifice was not a necessary function in the reduced thrust 1970 rocket configuration, and thus not installed.
Ray’s other “revelation”, that the LNG was never burned in the rocket combustion chamber, and did not provide additional thrust, is also not correct. A frame snapshot from my 16mm film of one of the early tune-up runs confirms, with the diamond exhaust shock waves, that we were efficiently burning the LNG with the oxygen-rich H2O2 decomposition gasses in the rocket combustion chamber. This was also borne out by the performance difference without and with LNG in test runs. When the 2nd stage injector assembly explosively failed on the first run, I later reconfigured the rocket to use the 3rd stage injectors instead. We ran several tests to optimize the LNG flow, going from an LNG-rich to a lean mixture, modifying the 3rd stage LNG injectors (to improve combustion) as well.
Our fastest H2O2-only run netted a mile average speed of 484 miles per hour (run #10). After LNG-tuning we achieved 557 from a standing start (run # 12), and later, 650 peak with a push start during the record runs. That standing start 15% performance boost, along with the visual evidence, certainly indicates effective combustion of the purposely reduced LNG fuel capacity.