Filipino aviation enthusiasts and avgeeks have been buzzing with excitement over the arrival of the NASA DC-8 in the Philippines to conduct research on air quality. The highly modified Douglas DC-8, registered as N817NA, is currently in Clark and has been performing low passes in various areas, including a few over Ninoy Aquino International Airport (NAIA). The NASA DC-8 is one of the few remaining DC-8s still in operation today.
Therefore, it was a real treat for planespotters and avgeeks to see a Douglas DC-8 still flying, an aircraft that is mostly seen in museums and pictures. Even more so, this particular DC-8 is the only one in the world operated by NASA. Unfortunately, the plane may soon be retired and replaced by a Boeing 777-200ER.
The NASA DC-8 initially served Alitalia in May 1969 as I-DIWK. Originally powered by Pratt & Whitney JT3D low-bypass turbofan engines, the plane was re-engined in 1984 with its current CFMI CFM56-2 turbofan engines, the same family of engines used by the Airbus A320, Boeing 737NG, and Airbus A340-300. NASA acquired the aircraft in 1985.
A Flying Science Laboratory
In 1985, NASA introduced its DC-8-72 Airborne Science Laboratory. The aircraft spans 157 feet in length with a 148-foot wingspan and boasts a range of 5,400 nautical miles. Capable of flying at altitudes from 1,000 to 42,000 feet for up to 12 hours, it primarily serves science missions averaging 6 to 10 hours. The aircraft’s design allows it to carry 30,000 pounds of scientific instruments and equipment, accommodating up to 45 researchers and flight crew members.
Stationed at NASA’s Armstrong Flight Research Center in Palmdale, California, the DC-8 serves as a flying science laboratory. It’s equipped with a suite of sensors and data systems, including Iridium and Inmarsat satellite communications, to support a wide range of scientific endeavors. Researchers from federal, state, academic, and foreign institutions utilize the DC-8 to collect valuable data for experiments that contribute to our understanding of Earth’s surface and atmosphere. The aircraft’s versatility allows it to engage in sensor development, satellite sensor verification, space vehicle launch or re-entry telemetry data retrieval, and optical tracking, among other research studies.
Innovations and Contributions
The DC-8 has been instrumental in advancing sensor technology and verifying satellite instruments. It provides a cost-effective platform for testing prototype satellite instruments, ensuring that potential problems are addressed before their launch into space. For instance, the Active Sensing of CO2 Emissions over Nights, Days, and Seasons (AS-CENDS) campaign utilized the DC-8 to demonstrate improved airborne lidar instrument performance for atmospheric carbon dioxide measurements. Similarly, the Convective Processes Experiment – Aerosols and Winds (CPEX-AW) campaign, in collaboration with the European Space Agency, aimed to calibrate and validate the Atmospheric Dynamics Mission-Aeolus wind lidar satellite.
Beyond technological advancements, the DC-8 has played a crucial role in environmental research. It has supported missions like Operation IceBridge, the largest airborne survey of Earth’s polar ice, and the Fire Influence on Regional to Global Environments – Air Quality (FIREX-AQ) mission, which investigated the impact of fires on air quality. These missions underscore the DC-8’s ability to facilitate comprehensive studies on Earth’s environmental systems, contributing invaluable data to NASA’s Science Mission Directorate.
About the DC-8-72
The DC-8-72 is part of a unique set of aircraft, the result of an innovative conversion program that breathed new life into the classic Douglas DC-8 series. This transformation involved the DC-8-71, DC-8-72, and DC-8-73 models, which were originally the -61, -62, and -63 variants of the DC-8. The core of this upgrade was the replacement of the original JT3D engines with the CFM International CFM56-2 engines. These new engines were a significant advancement, being high bypass turbofans capable of producing 22,000 lbf (98.5 kN) of thrust, which offered improved fuel efficiency.
In addition to the engine upgrade, the aircraft saw the installation of new nacelles and pylons, crafted by Grumman Aerospace. This was a crucial part of the conversion, ensuring that the new engines were properly integrated into the aircraft’s design. Despite these enhancements, the maximum takeoff weights of the aircraft remained unchanged. However, there was a slight reduction in payload capacity due to the increased weight of the new engines.
The conversion process for the DC-8-71 was notably more complex than for the other two models. This complexity arose because the -61 variant did not feature the improved wings and repositioned engines found on the -62 and -63 models, necessitating more extensive modifications.
These conversions were officially recognized in 1982 when all three models received certification. By the end of the program in 1988, a total of 110 aircraft from the 60-series Super DC-8s had been converted. The entire conversion program was managed by Cammacorp, in collaboration with CFMI, McDonnell Douglas, and Grumman Aerospace. Following the completion of the last aircraft conversion, Cammacorp was disbanded, marking the end of this significant chapter in aviation history.
First love never dies. I fell in love with airplanes and aviation when I was a kid. My dream was to become a pilot, but destiny led me to another path: to be an aviation digital media content creator and a small business owner. My passion for aviation inspires me to bring you quality content through my website and social accounts. Aviation is indeed in my blood and blog!
