An ongoing subcontracting program which has proved quite a headache since its inception...

SOFIA has retained much of its United Airlines color scheme.

Artist's painting and scale model of the SOFIA aircraft.

Type: composite aperture airborne observatory



Significant date: circa 1999

NASA selected Universities Space Research Association (USRA) in 1996 to develop and operate the SOFIA Airborne Astronomical Laboratory to replace the .91-meter Kuiper Airborne Observatory, a C-141 that flew successfully for over 20 years, named for Gerard P. Kuiper, a University of Arizona astronomer who conceived the idea of a flying astronomical observatory in the mid-1960s. The KAO was a converted C-141 military cargo plane equipped with a 36-inch reflecting infrared telescope. It began operations in 1974, and for nearly 22 years conducted scientific missions, making some of the most important discoveries in infrared astronomical science. Notable among the KAO's accomplishments were the first sightings of the rings of Uranus, the identification of Pluto's atmosphere, the discovery of water vapor in the thick atmospheres of Jupiter and Saturn, and the development of clues to the early chemical composition of the solar system.

The winning proposal by USRA was selected over others submitted by Hughes STX, Lanham, MD; Lockheed Martin Missiles and Space, Sunnyvale, CA; and the University of Texas at Austin. SOFIA's telescope will be more than 2-1/2 times larger than the KAO's affording even greater opportunity for scientific discovery. The contract calls for the selected company to acquire an existing Boeing 747 SP aircraft, design and implement a modification program to accommodate installation of a large infrared telescope, test and deliver the flying astronomical observatory to NASA, and provide mission and operations support in five-year increments. USRA's proposal calls for operating the aircraft out of Moffett Federal Airfield, Mountain View, CA.

All of the offerors submitted very good proposals, said Dr. Wesley T. Huntress Jr., NASA Associate Administrator for Space Science. The USRA proposal stood out amongst these on the basis of mission suitability and cost. SOFIA will fly in the Earth's stratosphere, between 41,000 and 45,000 feet, carrying a 98-inch (2.5 meter) telescope to view objects in the Universe in the infrared region of the electromagnetic spectrum. At this altitude, in the clear, dry environment on the very edge of space, SOFIA will enable scientists to study radiant heat patterns from stars, planets and other celestial sources.

The SOFIA telescope will be provided by the German space agency, DARA, pending completion of a formal Memorandum of Understanding with NASA. DARA also will participate in the operation of SOFIA. In addition, as many as 15 state-of-the-art science instruments will be developed by SOFIA researchers and integrated within the flying laboratory on an annual basis by the selected contract awardee. The contractor also will manage an extensive SOFIA educational outreach program for teachers and students in kindergarten through college.

It is anticipated that the 747 SP aircraft will be purchased in early 1997 and modifications to the vehicle will begin in mid-1998. The telescope will be integrated and tested by late in the year 2000, with science flights scheduled to begin in 2001. Radiation data from astronomical sources cannot typically be collected at terrestrial sites because it is absorbed by atmospheric water vapor before it reaches the Earth's surface. This applies to most infrared light, gamma rays, X-rays and ultraviolet light. SOFIA will overcome this limitation by operating above more than 85 percent of the Earth's atmosphere and 99 percent of its radiation-absorbing water vapor. SOFIA will also have the advantage of being able to switch science instruments, to be upgraded, and to be deployed rapidly to diverse geographic locations throughout the northern or southern hemisphere to observe astronomical areas of emerging interest.

The primary science objectives of SOFIA are to study the composition of planetary atmospheres and surfaces; to investigate the structure, evolution and composition of comets; to determine the physics and chemistry of the interstellar medium; and to explore the formation of stars and other stellar objects. With up to 160 flights annually, SOFIA will be able to conduct a wide array of scientific investigations and provide hands-on, real-world educational opportunities for an anticipated 500 teachers and students. The innovative SOFIA contract calls for development and operation of the flying observatory in a totally privatized manner. The SOFIA science program is modeled on the highly successful operation of the Hubble Space Telescope by the Space Telescope Science Institute.

NASA selected a team led by the Universities Space Research Association (USRA), Columbia, MD, for the award of what was initially an estimated $484.2 million contract to acquire, develop and operate the new Stratospheric Observatory For Infrared Astronomy (SOFIA). The Cost-Plus-Incentive and Award Fee-type contract had a base period for development plus one five-year operations cycle. The contract also contained an option period for one additional five-year operations cycle. SOFIA was expected to be operated for at least 20 years. The total contract value included the base period plus all priced options. The contract was managed by NASAs Ames Research Center, Mountain View, CA.

Other team members included Central Texas Airborne Systems (CTAS), Waco, TX, a division of Raytheon; United Airlines, San Francisco; an alliance of the Astronomical Society of the Pacific and The SETI Institute, both of Mountain View, CA; Sterling Software, Redwood City, CA; and, the University of California at Berkeley and Los Angeles. The SOFIA program was a stellar example of NASA's new ways of doing business. The agency took the parts of a space science program that the private sector could do better and more cost effectively than the government, and had a competitive selection for the privilege of performing those duties, said NASA Administrator Daniel S. Goldin. In addition, they combined the development and operations phases of the program into one seamless transition, ensuring that this flexible, international airborne observatory would serve the scientific community efficiently for two decades or more.

Until its demise in 2003, Scaled Composites' sister company, Scaled Technology Works (STW) of Montrose, Colorado, designed, certified, produced, and delivered fully integrated composite structural components, major assemblies, and complete general aviation aircraft. The company was selected by Raytheon to provide the composite aperture for NASA's Stratospheric Observatory for Infrared Astronomy (SOFIA), an international cooperative NASA program. The contract value was approximately $1.4 million of advanced composite assemblies for the 747SP aircraft used for the SOFIA program.

STW successfully competed for and won a contract to produce tooling, composite components fabrication and assembly of the SOFIA aperture. The aperture is a critical structural component of the telescope mounting system inside the observatory of the 747SP, which was to be the flying platform for SOFIA. STW's customer, Raytheon, was also under contract to the Universities Space Research Association for design, integration, and certification of the SOFIA aircraft. Work was done at Raytheon's Aircraft Integration Systems Waco (Texas) facility.

Soon after STW became STW Composites, the company was selected by L-3 Communications Integrated Systems as the Supplier of the Month for March 2002, for the SOFIA program. In a statement issued by L-3 Comm, Jerry Rasmussen said “STW has supported the Integrated Systems SOFIA Program by providing initiative in facilitating both Integrated Systems and NASA's design completion. In addition, STW has stepped up with excellent engineering support throughout the program. All the while, a predominant STW goal has been maintaining excellent customer communications and coordination. STW's relationship with Integrated Systems is one that strives for customer satisfaction by ensuring best value for the services provided. STW also puts a high priority on rapid response to the customer's schedule requirements and action items. STW continues to view Integrated Systems as a highly valued customer and strives to insure the future mutual success of our customer/supplier relationship."

SOFIA progressed steadily through key milestones: delivery of the German-built telescope in 2002; installation of the telescope into the aircraft in 2003; structural testing of the aircraft and initial ground-based testing of the telescope in 2004; and completion of the first-flight configuration of the NASA telescope cavity door in 2005.

The USRA then announced on February 6, 2006 that its teammate L-3 Communications Integrated Systems had completed all major physical modifications required for initial flight-testing of NASA’s Stratospheric Observatory For Infrared Astronomy (SOFIA). The announcement moved SOFIA into the final phase of the Heavy Maintenance Visit, final ground testing and FAA verifications. Initial flight tests are scheduled for the latter part of 2006, depending on funding. After flight testing and functional testing of the telescope and cavity door, SOFIA will be operated at the NASA Ames Research Center in Mountain View, CA.

SOFIA is a Boeing 747 extensively modified to carry a 50,000-pound, 2.5-meter infrared telescope provided by Germany. SOFIA will fly at altitudes up to 45,000 feet – above 99% of the Earth’s water vapor – to capture infrared images not possible by even the largest ground-based telescopes.


Germany has been substantially involved in the SOFIA program for over 20 years. The German Aerospace Center – or DLR – funded and oversaw design and development of the SOFIA telescope by a team of German companies. In 2004, the DLR funded the University of Stuttgart to establish the German SOFIA Institute, which coordinates German participation in the program. SOFIA’s science staff already includes German researchers helping to move the program to its first science observations. In return for Germany’s considerable investment in SOFIA, 20% of SOFIA’s observing time will be for German astronomers.

SOFIA will provide an excellent platform for the study of black hole environments, galactic evolution, the chemical composition of interstellar gas clouds, complex organic molecules in space, and the formation of stars and solar systems. SOFIA will also provide a unique opportunity for educators to partner with scientists on research missions.

“The development phase of SOFIA is virtually complete,” said USRA President David Black. “We plan to start flight testing this year and once that is complete we can start flying science missions. That is when the program will begin to reap tangible benefits from this significant investment by NASA and the German government.”


SOFIA's cabin in front of the science instrument mounting flange. The flange extends into the cabin from the pressure bulkhead behind which lies the telescope cavity and telescope.

The SOFIA observatory aircraft, a Boeing 747SP, with all external modifications completed as of February 3, 2006, in a hangar at L-3 Communications Integrated Systems in Waco, TX. The light-colored band is the door over the cavity containing the telescope.

Population: 1 [N145UA]


Main sources:
- Flug Revue
- STW Composites website (now extinct)
- NASA Ames Research Center

The cavity door was subcontracted by L3 to STW Composites.

Detailed drawing of the aperture.