RD-180 engines. Credit: ULA
RD-180 engines. Credit: ULA

James M. Knauf, a retired U.S. Air Force colonel,  is the chairman of the American Institute of Aeronautics and Astronautics’ Space Transportation Technical Committee. He served as deputy director of the Air Force’s Expendable Launch Vehicle Program at the Space and Missile Systems Center and deputy director of space acquisition at the Pentagon before going to work for Booz Allen Hamilton and Scitor Corp. 

Daniel Gouré’s op-ed “Why Does The Air Force Want To Destroy The Struggling U.S. Space Launch Business?” is inaccurate and misleading.

While it is true the Air Force “insists it must depend on Russian rocket engines for at least another six years,” this is a conservative estimate of the time required to develop an engine, integrate it into a rocket and certify the rocket to launch national security payloads. Lockheed Martin and Pratt & Whitney began working with NPO Energomash to develop the RD-180 in 1992, but the engine did not fly until 2000, on an Atlas 3, and on Atlas 5 in 2002. RS-68 development took six years, from 1997 to first flight in 2002, after conceptual studies begun in 1988. Even fast-moving SpaceX took a decade to develop and fly the current version of its Merlin 1D engine, first flown in 2013 and developed 2011–2012 based on three previous Merlin 1 versions whose development presumably began shortly after SpaceX was founded in 2002.

Interestingly, Dr. Gouré’s omits the more costly Delta 4, whose RS-68 engine is also built by Aerojet Rocketdyne — a company that funds his employer, the Lexington Institute — or why it is not a near-term alternative to the Atlas 5/RD-180.

Presumably referring to the Falcon Heavy and the BE-4-powered Vulcan launch vehicle, he accuses the Air Force of a “high risk approach of launching important national security payloads aboard either the SpaceX system that has never been tried in such a mode or a new launch vehicle using a novel propulsion system.” No important national security payload will fly aboard ANY new launch system without first being certified to do so. Falcon 9 was certified, as will be the Falcon Heavy, which SpaceX also plans to fly sans paying customer and then with the low risk Air Force STP-2 payload before critical payloads are flown. Note the Delta 4 Heavy Demonstration mission before national security payload flew.

And while the liquified natural gas BE-4 engine can be considered “novel,” RD-180’s oxygen-rich staged combustion was also considered “novel” when first introduced in the U.S., which had no similar capability and still doesn’t.

Finally, Dr. Gouré’s point about complicating the process and destroying the business case for launch service competitors by supporting the use of excess ballistic missile boosters is misleading. He leads the reader to conflate the business of large launch vehicles like Atlas 5, Delta 4 and Falcon with the very different business of smaller vehicles.

James Knauf
Rolling Hills Estates, California

Retired U.S. Air Force Col. James M. Knauf is the chairman of the American Institute of Aeronautics and Astronautics' Space Transportation Technical Committee. He served as deputy director of the Air Force's Expendable Launch Vehicle Program at the Space...