By Ryan Keith, AMRDEC Public AffairsOctober 16, 2014
REDSTONE ARSENAL, Ala. (Oct. 16, 2014) -- The Aviation and Missile Research Development and Engineering Center, in conjunction with the Redstone Test Center, has completed a historic test program demonstrating the effectiveness of a bio-fuel commonly referred to as Alcohol to Jet in two Army aircraft -- a UH 60A Black Hawk and a CH 47D Chinook.
Tests were conducted as a part of a congressionally-funded program to determine whether jet fuel made from non-food stock corn could safely power rotary wing aircraft and perform to Army requirements. The effort was part of a broader Department of Defense strategy initiated in 2009 to reduce dependency upon fossil fuels. ATJ-blends provide a renewable alternative to current aviation fuels, and address the Army Energy Security Strategy and Plans mandate that the Army certify 100 percent of its air platforms on alternative/renewable fuels by 2016.
Bio-fuels are made from renewable sources, such as algae, sugar, switch grass, plant oils and wood. Isobutanol is an alcohol-based bio-fuel produced from non-food stock corn.
"The corn is distilled much like the old moon shine stills of the past, and the fuel is extracted," said Bill Crawford, AMRDEC ATJ program director. "After undergoing a chemical process, the fuel is then available for possible usage in aircraft. I visited the refinery where it was produced. It was a 1/100 scale of a normal refinery and they could scale this up rapidly to produce bio fuels if there's a demand."
After the refining process, the Alcohol to Jet fuel is blended in a 50 percent solution with Jet Propellant 8. ATJ lacks aromatics, an essential part of fuel needed to ensure that the seals within the fuel system swell to prevent leakage. The tested ATJ, therefore, cannot completely replace fossil fuels but could be used to reduce dependency.
AMRDEC's Aviation Development Directorate managed the program, while the Aviation Engineering Directorate's Propulsion Division developed a certification and testing program that was implemented at test facilities throughout the country. The tests consisted of ground runs of engines, ballistic testing of fuel cells, chemical analysis of fuel, inspection of engines, and lastly the actual flight in the aircraft. After all required ground safety of flight tests were successfully completed in 2013, the first flight of an Army helicopter, a UH 60, using ATJ fuel occurred at Redstone Arsenal last Nov. 5.
"As DoD moves toward using commercial jet fuel in the continental U.S. and these fuels become more prevalent in the commercial pipeline, it will become increasingly important that Army aviation be prepared to ensure there are no operational issues with these fuels in our aircraft," said Dale Cox, an engineer with AMRDEC's Aviation Engineering Directorate and one of the Army's experts on the certification of alternative fuels.
The UH 60 aircraft was flown for more than 180 hours using the ATJ fuel, with flight tests concluding in 2014. According to AED officials, there were no unanticipated drops in engine performance and engine inspections showed no apparent ill-effects caused by the bio-fuel blend.
In the program's second phase, ground and flight tests are being conducted utilizing the ATJ with a CH 47 Chinook. The first flight, called a success by Crawford, occurred Sept. 15. Flight testing will continue through the end of October for a total of 30 hours of flight time. Upon completion, AED will begin the process of evaluation of both Black Hawk and Chinook data prior to allowing an ATJ blend to become certified as a replacement fuel for JP-8.
"From what we have heard to this point, flying with this fuel blend hasn't given us any technical surprises," said George Bobula, AED's Propulsion Division chief engineer. "In all likelihood, this fuel blend will be incorporated into the jet fuel specification for Army use."
The certification of ATJ is a significant event for the Army and the Department of Defense.
"The three services began a collaborative effort in certifying this ATJ blend for use on all DoD aviation platforms," Bobula said. "In the process, we have established a test protocol for certification of other alternative fuels. As significant as certifying the ATJ blend is, having DoD collaboratively establish the path forward for future fuel, and then to collaboratively pursue that path, is a major breakthrough."
The Aviation and Missile Research, Development and Engineering Center is part of the U.S. Army Research, Development and Engineering Command, which has the mission to develop technology and engineering solutions for America's Soldiers.
RDECOM is a major subordinate command of the U.S. Army Materiel Command. AMC is the Army's premier provider of materiel readiness -- technology, acquisition support, materiel development, logistics power projection, and sustainment -- to the total force, across the spectrum of joint military operations. If a Soldier shoots it, drives it, flies it, wears it, eats it or communicates with it, AMC provides it.
Editor's note: Isobutanol is an alcohol which is chemically converted into hydrocarbon molecules that resemble petroleum-based jet fuel molecules. The alcohol "isobutanol" which is made from corn (or sugar) is the precursor/ingredient for producing alcohol-to-jet.