Guy Norris/LOS ANGELES

THE OPERATIONAL TEST and evaluation of three Lockheed Martin F-16A/B mid-life update (MLU) aircraft has been put back by around three months while the manufacturer reworks wire harnesses which are "below specification."

The wiring problem, which is related to uneven solder used in some harness joints, has affected all five trial-verification-installation (TVI) F-16s involved in the multi-national programme (Flight International, 10-16 March).

The three aircraft undergoing re-wiring were due to have been flown from Texas to Leeurwarden AB in the Netherlands in early May. "The ferry flight date has been moved to the end of July because of the rework of the wiring," says the US Air Force.

The USAF F-16A TVI aircraft, with a Royal Danish AF F-16B, are scheduled to continue flying at Edwards AFB, California. "As it's not a safety of flight consideration, we've elected to delay inspections of the wiring until all four tapes [covering the full upgrade], are tested. We think it is more important to keep on with the programme," says the USAF.

Testing of the three European-based TVI aircraft, a Belgian F-16A, a Netherlands B and a Norwegian A, is expected to be accelerated in the third quarter of this year in a bid to make up some of the lost time.

Four lead-the-fleet (LTF) MLU aircraft are apparently not affected by the quality issue as the problem was caught before it was too late, says the USAF. These aircraft will enter the test phase in August, concurrently with the TVI fleet.

Testing of the MLU aircraft at Edwards, is now at roughly the half-way point, with flight tests of Tape 3 due to begin in October. Tapes 1 and 2 covered radar, communication, navigation and other upgrades related to the Texas Instruments modular mission computer at the heart of the upgrade.

Tape 2 particularly focused on the improved weapons delivery capability of the MLU, including simulated firings of the AIM-9 Sidewinder, Hughes AIM-120 AMRAAM, air-to-air gunnery, bombs drops, and firing of rockets and Hughes AGM-65 Maverick missiles.

Tape 3 will cover newer capabilities of the MLU including the improved data modem, advanced Haseltine APX-113 identification friend-or-foe along with the digital terrain system.

This phase, due to last until April 1997, also includes captive carriage trials of the Penguin anti-ship missile for the Royal Norwegian Air Force. The F-16 MLU development contract was awarded in July 1991, with the follow-on kit production contract awarded in 1993. In total, the contracts are worth £1.1 billion ($1.65 billion).

Source: Flight International