F135 testing to remain on track

During a recent qualification test on an F135 CTOL engine, an incident occurred resulting in damage to the forward section of the engine. The damage is limited to the fan and high compressor sections of the engine. A redesigned turbine section of the F135 engine installed on this engine was unaffected and not involved.

Reuters reports on the story here.

Pratt & Whitney is currently conducting a thorough review and inspection of the engine to determine the root cause of the damage and minimize impact to ongoing engine testing.. According to Graham Warwick of Aviation Week, primary contractor Lockheed Martin has confirmed that the incident will cause no delay to flight testing.

Second generation hardware designs were being evaluated in this test and are not installed in the F135 engines currently powering the flight test program. As Reuters reports, at the time of the incident, the engine had run through 2455 cycles, an amount equal to eight years of operation. The first generation hardware installed on existing flight test engines has already completed this testing and continues to perform well. The affected engine was a system, design and demonstration engine, and identifying issues is not unusual and is part of the process of retiring risk before the engine becomes operational.

These types of incidents occur on all engine programs at this stage of development. Because the F135 is derived from the proven F119, we have had relatively few incidents. In more than 12,000 hours of ground and flight testing we have already retired more than 90 percent of the risk associated with the F135.

Even for a high quality engine manufacturer like GE, an entirely new engine like the alternate engine is likely to experience similar challenges. This has already occurred with at least a couple of incidents on the GE alternate engine. As Reuters notes, Secretary Gates has said there is “there's no reason to believe that that prototype engine, or that that new engine would not encounter the same kinds of challenges and issues that other developmental engines on this aircraft as well as others have encountered in the past.”

Our focus remains on continuing to support a successful flight test program, continuing to work aggressively towards our cost goals, and continuing to retire the remaining risk in our system, design and demonstration engines.