The 1970s and the Rise of Synthetic Fuels

NASAs interest in alternative fuels did not end with liquid hydrogen; syn­thetic fuel research, joined with research on new, more aerodynamically effi­cient aircraft configurations, took off in the 1970s and 1980s, as rising oil prices and a growing concern about mankind’s (and aviation’s) impact on the environment pushed researchers to seek alternatives to oil-based fuel.[1482]

In 1979, NASA Langley released an aircraft fuel study that compared liquid hydrogen, liquid methane, and synthetic aviation kerosene derived from coal or oil shale.[1483] The study took into account factors including cost, capital requirements, and energy resources required to make the fuel. These factors were considered in light of the practicality of using the fuel in terms of the fuel production processes, transportation, stor­age, and its suitability for use on aircraft. Environmental emissions and safety aspects of the fuel also were considered. The study concluded that all three fuels met the criteria, but that synthetic aviation kerosene was the most attractive because it was the least expensive.[1484]

Despite the promising findings of NASA’s study, however, synthetic fuel never made it into mainstream production. The fuel’s capital costs are still relatively high when compared with oil-based jet fuel, because new synthetic fuel production plants have to be built to produce the fuel.[1485] Private industry has been hesitant to get into this business, fearing it would not make a return on its investment. If oil prices were to drop—as they did in the mid-1980s— companies that invested in synthetic aircraft fuel production would find it difficult to compete with cheap oil-based jet fuel.

Regardless of industry’s hesitation, Government efforts to develop and test alternative fuels are springing to life again as a result of a return to high oil prices and a growing concern about the impact of emissions on air quality and climate change. The U. S. Air Force has engaged in a systematic process to certify all of its aircraft to fly on a 50/50 blend of oil-based jet fuel and synthetic fuel. Air Force officials hoped that testing and flying their own aircraft on synthetic fuels would encourage com­mercial airlines to do the same, believing that if the service and airline industry could create a buyer’s market for synthetic fuel, then the energy industry might be more amenable to investing the money required to build synthetic fuel plants for mass production.[1486]

NASA has also begun testing the performance and emissions of two synthetic fuels derived from coal and natural gas. While the Air Force’s interest in alternative fuels is largely related to concerns about oil price volatility and the national security risks of relying on foreign oil suppli­ers, NASA has embarked on alternative fuels research largely to study the potential for reducing emissions. NASA’s research effort, which is being conducted at NASA Dryden, seeks to closely measure particulate levels. "Even though there are no current regulations for particulates, we see particulates as being very important,” said Bulzan, who is lead­ing the alternative fuels effort. "They are very important to local air qual­ity when the aircraft is taking off and landing at the airport, and they can also generate cloud formation that can affect global warming.”[1487]

Both the USAF and NASA are using synthetic fuel derived from a process developed by the Germans in World War II known as Fischer – Tropsch. In this process, a mixture of carbon monoxide and hydrogen is used to create liquid hydrocarbons for fuel. NASA Dryden’s latest alter­native fuels testing, which took place in early 2009, involved fueling a grounded DC-8 with both 100-percent synthetic fuel and a 50/50 blend. The test results are being compared with baseline tests of hydrocarbon fuel emissions tests performed in the DC-8 in 2004. Air Force research­ers were on hand to help measure the emissions.[1488]

NASA and the Air Force are also working with Boeing to explore the possibility of using biofuel, which may prove to be cleaner than fuel derived from the Fischer-Tropsch process. The main obstacle to biofuel use at this time is the fact that it is difficult to procure in large quantities. For example, algae are attractive feedstock for biofuel, but the problem lies in being able to grow enough. NASA has begun to take on the feed­stock problem by setting up a Greenlab Research Facility at NASA Glenn, where NASA researchers are seeking to optimize the growing conditions for algae and halophytes, which are plants tolerant of salt water.[1489]

In conclusion, the oil crisis and growing environmental awareness of the 1970s presented a critical opportunity for NASA to reclaim its mantle at the forefront of aeronautics research. NASA-led programs in fuel-efficient engines, aircraft structures, and composites—as well as the Agency’s contribution to computational fluid dynamics—planted the seeds that gave private industry the confidence and technological know­how to pursue bold aircraft fuel-efficiency initiatives on its own. Without NASA’s E Cubed program, U. S. engine companies may not have had the financial resources to develop their fuel-saving, emissions-reducing TAPS and TALON combustors. E Cubed also spawned the open-rotor engine concept, which is still informing engine fuel-efficiency efforts today. The turbulent 1970s also created the opening for NASA Langley’s Richard Whitcomb to proceed full throttle with efforts to develop supercritical wings and winglets that have revolutionized fuel-efficient airframe design. And NASA’s research on alternative fuels during the 1970s, if stillborn, nevertheless set the stage for the Agency to play a significant role in the Government’s revitalized alternative fuels research that came with the dawning of the 21st century.

Addressing the Nation’s scientific leadership in 2009, President Barack Obama compared the energy challenge facing America to the shock of Sputnik in 1957, declaring it the Nation’s new "great project.”[1490] Reflecting the increasing emphasis and rising priorities of Federal envi­ronmental research, NASA had received funding to support global climate studies, while NASA’s aeronautics research received additional funding to "improve aircraft performance while reducing noise, emissions, and fuel consumption.”[1491] Clearly, NASA’s experience in energy and aeronautics positioned the Agency well to continue playing a major role in these areas.

As the Agency enters the second decade of the 21st century, much remains to be done to increase aircraft fuel efficiency, but much, like­wise, has already been accomplished. To NASA’s aeronautics research­ers, inheritors of a legacy of accomplishment in flight, the energy and environmental challenges of the new century constitute an exciting stim­ulus, one as profoundly intriguing as any of the other challenges—super­sonic flight and landing on the Moon among them—that the NACA and NASA have faced before. Those challenges, too, had appeared daunting. But just as creative NACA-NASA research overcame them, those in the Agency charged with responsibility for pursuing the energy and envi­ronmental challenges of the new century were confident that they, and the Agency, would once again see their efforts crowned with success.