The Japanese Defence Agency (JDA) has extended development of the Mitsubishi F-2A/B support fighter by another three months after the discovery of fresh structural load problems, this time at the base of the aircraft's fin.
Recent XF-2 flight tests revealed excessive loads at the root of the tail while the aircraft was undergoing high subsonic-speed roll intended to generate a negative 1g load. Before the inverted roll could be completed, flight test engineers on the ground detected high loads in a critical area and ordered the trial to be aborted.
The negative 1g manoeuvre was part of a series of load tests that must be completed before certification, targeted for the end of March. According to the JDA, development completion of the F-2, which is based on the Lockheed Martin F-16, has been delayed until June, putting the programme a year behind schedule.
A series of wing cracks, discovered during static testing, resulted in a nine-month slippage (Flight International, 16-22 June, 1999). The composite wing, 25% larger than that of the F-16, has been reinforced. It is unclear whether these changes have led to the excessive loads passing through the fighter's empennage, but industry sources are playing down the significance of the problem.
Source: Flight International