USAF Conducts First GBU-72 Advanced 5K Penetrator Release

The United States Air Force has announced the successful first release of the GBU-72 Advanced 5K Penetrator. In an October 7 test, an F-15E Strike Eagle of the 96th Test Wing successfully released the 5,000-pound bunker buster over the Eglin Air Force Base test range, at an altitude of 35,000 feet.

The October 7 test successfully concluded a test series of three flights planned by the 780th Test Squadron and performed by the 40th Flight Test Squadron, with an earlier test in the series performing the first-ever weapons load, flight and release of the weapon on July 23. The series’ test goals were to demonstrate the safe release of the GBU-72 from the aircraft, as well as validating the ability of a modified Joint Direct Attack Munition tail kit originally designed for a 2,000 pound bomb to control and navigate a 5,000 pound weapon.

The 780th Test Squadron also planned the largest ever arena test conducted at Eglin as part of the ground test series of the GBU-72. According to the Air Force, the open-air test where the warhead detonates, surrounded by blast pressure sensors and fragment counting equipment to help evaluate bomb lethality, was over twice the size of the previous record holder. For its efforts on the program, the 780th Test Squadron recently received the External Team of the Quarter award from the Air Force’s Armament Directorate.

The detonation of a GBU-72 during arena testing, with the blast shockwave visible (US Air Force)

“Test series of this magnitude are never successful, overall, because of just a single person or organization,” said Ronald Forch, 780th Test Squadron Programming Engineer over the GBU-72 flight and ground test efforts. “They are ultimately successful because the test engineer is able to perform a role very similar to that of a symphony conductor guiding the performance of a series of consecutive miracles – none any more important than the other.”

According to James Culliton, GBU-72 Program Manager, the GBU-72 is designed for use on both fighter and bomber aircraft, with “substantially” enhanced lethality compared to previous bunker busters like the GBU-28. Advanced modeling and simulation techniques and processes used in the program mean that early prototypes of the bomb are already “production representative”, with the process repeatable for future direct attack weapon development. This approach allowed for operational test partners to be brought in sooner with “eyes on, hands on participation, validating our design and procedures sooner while including input that improves the weapon”, with Culliton describing the collaboration with the 780th Test Squadron and 40th Flight Test Squadron as “the best I’ve experienced in acquisitions”.

A GBU-72 mounted on the centerline pylon of an F-15E Strike Eagle (US Air Force)

The Air Force has credited the 780th Test Squadron’s planners and the 40th Flight Test Squadron’s aircrews with “making the right choices, creating new procedures and adjusting quickly” to ensure the correct release of the GBU-72 and that the program remained on schedule. Following the successful conclusion of the test series, the GBU-72 program will now conduct further JDAM integration test flights, with development and operational testing planned to start in 2022.