GE/Rolls-Royce F136 엔진 개발 소식, F-35 JSF alternate engine...

 

AW&ST 3. 22.字에 보도된 GE/Rolls-Royce 의 F-35 JSF 에 장착되는 F136 엔진 개발 소식입니다. 작년 미 정부는 의회의 반대에도

불구하고 F136 엔진 개발지원 예산을 삭감한 바 있습니다. 또한 작년 10월, F136 엔진 시험과정에서 떨어져 나온 nut 에 의해 blade

가 파손되는 사고가 발생, 계획된 일정 보다 약 1년여 이상 지연될 거라는 보도가 있었습니다.

 

다행히 이러한 문제점을 해결하고, 개발을 순조롭게 진행하고 있다는 내용입니다. GE/RR 측은 Pratt & Whitney F135 엔진 대비 약

5% 향상된 내구성을 지니고 있으며, 2013년까지 개발을 완료하고 F-35 JSF Lot 7 생산분 부터 경쟁에 참여하겠다고 밝혔습니다.

 

 

  ⓒ Flickr

 

Maximum Thrust

Production-standard JSF alternate engine completes first full-power run

Aviation Week & Space Technology, 03/22/2010

Author : Guy Norris

 

Away from the funding furor in Washington over the F136 alternate engine for the Joint Strike Fighter, the General Electric/Rolls-Royce development team is pushing ahead with full performance tests after running the production-configuration engine in maximum afterburner for the first time.

 

The milestone was achieved on Engine 006, the first of six system development and demonstration (SDD) production-standard F136s due to be run by the end of 2010, and it clears the engine for unrestricted afterburner operation, says the team. Performance, durability, operability and control data from the tests provide the basis for initial flight release in 2011 of the F-35 conventional-takeoff-and-landing (CTOL) version.

 

“The plan is to have more than 1,000 hr. on the latest SDD configuration,” says GE/Rolls-Royce Fighter Engine Team President Al DiLibero. “This will be a tri-variant configuration, and we’re confident we’re in a good position to meet the aircraft specification.” Although the focus is on tests for the F-35A conventional variant engine, GE/Rolls-Royce says the work also lays the foundation for trials later this year that will support tests of the short-takeoff-and-vertical-landing (Stovl) version.

 

“Make no mistake about it, 2010 is the year of execution. What we are doing on Engine 006 will pave the way for the rest of the program,” says DiLibero. Tests also proved changes to the instrumentation, which failed in its original configuration and twice interrupted initial ground runs of the first SDD engine last year.

 

The configuration also includes revisions to clearances in the No. 4 bearing and strengthened attachments on the diffuser splitter between the combustion chamber and turbine inlet, both due to findings of the initial SDD tests. The beefed-up bolts in the combustor/diffuser/nozzle assembly were added after borescope inspections revealed that a loose unit caused turbine blade impact damage during runs of Engine 005 last October.

 

With all the improvements in place, DiLibero says Engine 006 test results so far indicate performance and durability is exceeding design expectations and turbine inlet temperatures are cooler than planned. “So that’s more margin for durability, or power,” he adds. GE/Rolls-Royce declines to comment on the top thrust levels achieved in maximum afterburner, but the team previously said it anticipated an estimated 5% margin over the F-35’s baseline Pratt & Whitney F135 powerplant.

 

“Both engine developers are working to the same specifications, and our customer has made it clear it is not in anybody’s interests to be over. However, we’re on firm ground by saying we have margin,” says F136 marketing manager Tim Morison. GE/Rolls-Royce says the additional thrust may be particularly valuable for increasing weapons bring-back capability and hover performance for the F-35B Stovl version. “We think the three-stage low-pressure turbine is what drives the margin in Stovl,” Morison says.

 

Tests of Engine 006 are being run in GE’s altitude test facility in Evendale, Ohio, which simulates inlet conditions at both high altitude and high Mach numbers. For full afterburner tests, the engine was connected to the common exhaust system designed to accommodate both the F135 and the F136. one test of the engine, which incorporates a radial augmenter design derived from the F414 and F110-129-132, included running at maximum afterburner for more than 60 sec., the team says.

 

Preparations are also underway to add the next two test engines that together will help qualify several key technologies, including the F136’s counter-rotating vaneless turbine configuration and lightweight ceramic matrix composite vanes. Next in line is Engine 005, which will be used for both performance and operability tests at ArnoldEngineeringDevelopmentCenter (AEDC) in Tullahoma, Tenn., this summer. The engine is currently being built up and will be checked out at GE’s Evendale site before shipping to AEDC in the second quarter. Aeromechanical testing will be undertaken in mid-year using the second build of Engine 004.

 

“Engines 005 and 007 will be piggybacking off each other for operability and performance software tests,” says ­DiLibero. Engine 008 will be used throughout the second half of 2010 for CTOL accelerated mission testing in the Evendale altitude test facility, while Engine 009 is expected to run in the fourth quarter as part of a series of ingestion and vibration tests.A second build of Engine 006 will be used for the start of Stovl tests late in the year, DiLibero says.

 

“We have funding in fiscal year 2010, and we’ve had to work with the funding available,” says DiLibero, noting that the current test plan “supports the whole CTOL initial flight release in 2011.” The target for first flight of a F136-powered F-35 is December 2011, while the first flight of the Stovl version is planned for about a year later, with initial service release anticipated at the end of 2013.

 

DiLibero, the architect of last year’s surprise fixed-price contract offer for engines in low-rate initial production (LRIP) Lot 5, says that despite the continuing funding uncertainty, “we feel confident in what we can do, and what we can deliver. We’re willing to take on that risk.”

 

The proposal, which effectively brings forward by two years the date by which the F136 could be competed on the F-35, covers a fixed-price proposal for the initial 21 engines in LRIP Lot 5 instead of the original cost-plus contract of the directed buy plan for Lots 5 and 6. As currently envisioned, the aircraft in Lot 7 are the first F-35s that would be competed with both engines.

 

“With the restructuring of the program, we’ve got to look at how that comes out. However, we still feel confident in what we offered up last year,” says DiLibero. “All we want to do is have an opportunity to compete, and we’re so close to completing development of this program.”

 

GE/Rolls-Royce estimates $1.3 billion will be needed to finish the effort in the next five years, including all tooling and associated infrastructure. Of this, it says less than $1 billion is needed to complete development, versus almost $3 billion spent to date. “The bottom line is we’re still focused on what we need to deliver and on engine testing,” DiLibero says.

 

  ⓒ General Electric Co.

 

  ⓒ General Electric Co.

 

  ⓒ General Electric Co.

 

  ⓒ General Electric Co.