Defense

April 22, 2012

AEDC sets new testing record on F-22 Raptor engine

Tags:
by Philip Lornenz III
Arnold AFB, Tenn.
Air Force photograph by Rick Goodfriend
Dave Fischer, a Pratt & Whitney test engineer, inspects an F119 engine during a break in sea level Accelerated Mission Testing in AEDC's SL-2 facility.

The Arnold Engineering Development Center at Arnold Air Force Base, Tenn., recently completed a Continuous Improvement Program Life Extension Accelerated Mission Test on an F119 engine for the F-22 Raptor in the Sea Level 2 facility.

“The purpose of this particular test, a life extension Accelerated Mission Test, was to add another 2,165 TACs to it, which is equivalent to approximately another five years of life in the field,” said Rich Walker, AEDC F119 engine test project manager.

This established a new record of ground testing on the engine, a record which had been previously set at AEDC in May 2010.

However, Walker said more importantly, it’s what the test has accomplished for the war fighter.

“We’re taking an engine that’s already gone as far as it’s supposed to go by specifications and now we’re going to fly it the equivalent of five more years to see what happens, where the wear accumulates on parts, where things stop working the way they’re supposed to work,” he said. “The full life of an F119 is 8,660 TACs, which is equivalent to approximately 20 years of regular service in the field.

“This engine had already accumulated that many TACs and that equivalent time on it when it arrived here in June of 2011.”

Walker said the benefits of an AMT approach to ground testing the F-22 Raptor’s power plant are indisputable.

Scott Slabaugh, ATA project engineer on the test, inspects the F119 in AEDC’s SL-2 after an AMT test run.

“We’re trying to expand the tech order limits,” he said. “In other words, if there’s a tech order in the field that says you have to replace this part after so much time, because that’s a calculation, but if we can prove that no, you don’t need to replace it at this interval, you can wait until a longer interval. That saves the taxpayer a lot of money, because you’re not replacing parts before they need to be replaced.”

2nd Lt. Carl Tegtmeier, AEDC’s other Air Force project manager on the test, said, “This engine is still tested within its operational vibration limits, but it’s purposefully put out of balance so you see what the worst type of allowable vibrations will do to the wear of the engine.”

Walker said the most important reason for “testing before flight” can’t be measured in dollars.

“It’s a whole lot better to find out issues here on the ground than when it’s on an F-22 and there’s a pilot involved,” he said. “You don’t want to put the pilot in harm’s way.”

During an AMT test program, the engine undergoes a sequence of mission profiles designed to generate a specific number of Total Accumulated Cycles to simulate the operational wear it would experience in the field. An AMT mission profile is a sequence of throttle, horsepower and nozzle vector movements and specific amounts of operating time at idle, cruise, intermediate and maximum power settings.

The engine is pictured undergoing AMT testing in SL-2 with the augmenter activated.

The F119 AMT program includes AMT mission profiles which are conducted at three types of test conditions: ambient, heated and RAM. To minimize cost, the majority of the AMT missions are conducted at ambient conditions.

The Sea Level SL-2 and SL-3 test cells were designed to provide all three types of AMT test conditions, having an operating mode for each. In atmosphere-intake mode, the air supplied to the engine is drawn directly from outside via the atmospheric intake.

In heated-intake mode, the air supplied to the engine is first drawn over a set of steam coils, via the Sea Level facilities’ corrosion-air blowers, to set the desired inlet temperature. In RAM mode, pressurized, heated air is supplied to the engine from the C-Plant air-supply compressors. This simulates conditions that the engine would experience as the pilot flies the aircraft low and fast.

Now that the test has concluded, the engine will go back to the manufacturer, Pratt & Whitney, for a complete tear down, inspection and rebuild. The engine will return to AEDC later this year as a brand-new build for another cycle of AMT work.

 




All of this week's top headlines to your email every Friday.


 
 

 

Headlines September 17, 2014

News: Pentagon open to U.S. ground troops in fight against Islamic State - The Pentagon’s top general opened the door Sept. 16 to the possibility that U.S. combat troops would be needed in Iraq, as he publicly laid out President Obama’s still-developing plans to combat Islamic State insurgents through U.S. air power and relying on an...
 
 

News Briefs September 17, 2014

U.S. to assign 3,000 troops to fight Ebola The Obama administration is preparing to assign 3,000 U.S. military personnel to West Africa to combat the Ebola outbreak that has overwhelmed local health care systems and drawn appeals for help from the region and aid organizations. The troops will supply medical and logistical support and boost...
 
 
Navy photograph

Future USNS Fall River delivered

Navy photograph The joint high speed vessel USNS Fall River (JHSV 4) completes acceptance trials testing and evaluations in the Gulf of Mexico. The ship’s trials included dockside testing to clear the ship for sea and at-...
 

 
University of Alaska-Fairbanks photograph by Chris Larsen

NASA airborne campaigns focus on climate impacts in Arctic

University of Alaska-Fairbanks photograph by Chris Larsen Changes in more than 130 Alaskan glaciers are being surveyed by scientists at the University of Alaska-Fairbanks in a DHC-3 Otter as part of NASA’s multi-year Oper...
 
 
Air Force photograph by Michael J. Pausic

Future of NATO: Adapting to a new security environment

Air Force photograph by Michael J. Pausic Gen. Phillip Breedlove informs the assembled crowd about the results of the recent NATO Summit and the areas of instability that affect Europe that have regional implications. Seated in...
 
 
Image courtesy of NASA/CXC/M. Weiss

NASA’s Chandra X-ray Observatory finds planet that makes star act deceptively old

Image courtesy of NASA/CXC/M. Weiss A new study from NASA’s Chandra X-ray Observatory shows that a giant exoplanet, WASP-18b, is making the star that it orbits very closely act much older than it actually is. This artist&...
 




0 Comments


Be the first to comment!


Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>