Gallery: How Lufthansa Technik Maintains a Flying Observatory

Credit: Lufthansa Technik

NASA and the German Aerospace Center’s (DLR) flying observatory, SOFIA (Stratospheric Observatory for Infrared Astronomy), is back at Lufthansa Technik Hamburg for a C check. Read on to find out more about what makes this aircraft unique and what maintenance and overhaul work it will undergo.

Credit: Lufthansa Technik

SOFIA is a modified Boeing 747SP that serves as a flying laboratory. It is uniquely equipped with an on-board telescope that operates at altitudes of up to 14 km. (8.7 mi.) to perform astronomical observations in the infrared and submillimeter wavelengths high above the interference of the Earth’s atmosphere, where water vapor can hinder observations in infrared. In addition to the telescope, SOFIA has special electronics systems and a 4 x 6 m (13 x 19 ft.) door in the fuselage that opens for observations.

Credit: Lufthansa Technik

SOFIA’s scientific objective is to understand the development of galaxies and the formation and evolution of stars and planetary systems from interstellar clouds of gas and dust. It conducts around 160 astronomy flights a year.

Credit: Lufthansa Technik

The aircraft undergoes a C check approximately every three years and will be repaired in accordance with NASA regulations. SOFIA landed at Hamburg Airport on Sept. 30 and NASA defined the exact work packages for this layover.

Credit: Lufthansa Technik

The aircraft structure will undergo extensive inspections before necessary repairs are carried out. Its engines and the cabin, including paneling and floors, will be removed to carry out the test and maintenance work to check all cabling and ducts. Final checks, such as those on its engines and the cabin’s internal pressurization, are scheduled for mid-December.

Credit: Lufthansa Technik

SOFIA’s air conditioning system will also be given an upgrade. “This will enable us to adjust the temperature in the cabin very finely in the future,” says Heinz Hammes, SOFIA project manager at DLR’s Space Administration branch. “This is particularly important in the instrument zone, because every research instrument requires a precisely fitting ambient temperature.”

Credit: Lufthansa Technik

SOFIA’s on-board equipment will also receive a thorough overhaul during the C check. Its telescope will be overhauled at LHT by staff from the German SOFIA Institute at the University of Stuttgart and its scientific instrument, GREAT (German REceiver for Astronomy at Terahertz Frequencies)—which is mounted on the telescope—will be disassembled after landing and brought to the Max Planck Institute for Radio Astronomy in Bonn for maintenance and optimization.

Credit: Lufthansa Technik

To ensure safety in light of the COVID-19 pandemic, LHT and NASA have developed and coordinated comprehensive safety procedures for working in and on the aircraft. These include a rule that no more than 15 people may be on board at the same time and that technicians must wear mouth and nose protection. Only necessary personnel will have access to the aircraft.

Credit: Lufthansa Technik

More than 10,000 working hr. are earmarked for the scheduled work alone and LHT expects maintenance work to be completed by the beginning of February 2021, when SOFIA should be able to resume its scientific operations.