 |
| MarineCorpsAviationAssociation (flickr) |
Flaw With Lockheed’s $31 Billion Marine Copter Solved, U.S. Says - BNN Bloomberg:
(Bloomberg) -- Lockheed Martin Corp. has solved a major flaw with the U.S. Marine Corps’ new King Stallion helicopter that threatened to undercut congressional support for the $31 billion program.
The Lockheed-led project “has successfully tested a modification to the aircraft’s exhaust system” to solve the problem of hot engine exhaust being sucked back into one of the aircraft’s three engines, Megan Wasel, a spokeswoman for the Naval Air Systems Command, said in an email on Monday.
The Democratic chairman and top Republican on the House Armed Services Committee, Representatives Adam Smith, a Washington State Democrat, and Mac Thornberry, a Texas Republican, wrote the Defense Department earlier this year citing the exhaust problem as a key reason to resist the Defense Department’s request to shift $79 million in fiscal 2019 funds to the copter program from elsewhere in the budget.
The lawmakers agreed in July to shift the money based on assurances of progress.
The problem has been dealt with early in the program. The Marines want to buy 200 King Stallions. Only 20, including six test aircraft, are currently on contract.
Steve Schmidt, chief engineer on the King Stallion for Lockheed’s Sikorsky unit, said in a statement that the project’s “all-digital design” helped speed development of a solution to the exhaust problem and “test results show that all issues were successfully addressed.”
To contact the reporter on this story: Tony Capaccio in Washington at acapaccio@bloomberg.net
To contact the editors responsible for this story: Bill Faries at wfaries@bloomberg.net, Larry Liebert, John Harney
©2019 Bloomberg L.P.
 |
| flightglobal.com |
“[Exhaust gas re-ingestion] occurs when the hot engine gasses are ingested back into the system,” says Debbie Cleavenger, the H-53 helicopter programme office’s chief engineer. “It can cause anything from increased life-cycle costs, poor engine performance and degradation, time-on-wing decreases, engine overheating and even engine stalls.”
To solve the problem, NAVAIR put together a “tiger team” of government and Sikorsky engineers starting in April 2019 that had expertise in a wide variety of fields including engine performance, computational fluid dynamics, modeling and simulation, materials, structures, logistics, systems safety, reliability and maintainability, flight test, and fire protection and survivability, says NAVAIR. The team ran more than 30 tests and evaluated 135 potential different design changes.
“The systems constraints were significant,” says Cleavenger. “One change impacted multiple systems.”
After a design change was shown to redirect exhaust in simulations and to solve the re-ingestion issue, a retrofit was manufactured and a series of test flights were done to collect data to validate the model. NAVAIR concluded in December 2019 that the proposed fix would solve the problem. Source: flightglobal.com
No comments:
Post a Comment