Engines that won't have to be pulled for maintenance...
Sounds "Pie in the Sky" to me.
What will probably happen, is they will get their engines that don't get pulled, but they will just make it harder to fix, and more costly.
O ye of little faith!
This is probably not quite as outlandish is it first appears.
understand that they are talking about maintenance, not Repair. If you fly a bird down the intake of the engine, that’s a repair. If the engine simply runs and runs and runs, eventually it needs to be taken off and overhauled from end to end. That’s maintenance. (Also periodic maintenance that can be done on the engine while it is still hanging on the aircraft).
The B-52 airframe has a finite lifespan measured in number of flying hours. I think the majority of B-52 still flying have about 18000–20,000 flight hours (FH),And that’s over a span of about 50 years.
I believe the upper limit on the B-52 affects the wings first, at about 32,000 hours, give or take. So there’s about 12 to 14,000 flight hours left in the current fleet of B-52s (Average per aircraft). I don’t know what planning factor the Air Force is using, but when they look at the number of planned flying hours per year (important!: not including a war), then the B-52 will run out of life around 2040, plus/minus.
Rolls-Royce proposes using the F130 engine, used in some other USAF aircraft, which is based on a commercial engine called the BR 725. The BR 725 has a time between overhaul approximately 10,000 hours. This is the engine used in the Gulfstream 650, and part of the 700 series of engines used in previous Gulfstreams, so it has a maintenance history.
Assuming the changes to the engine the Rolls-Royce will make for the F130 to hang on the B 52 improve, rather than degrade, the endurance of it, then it is a good bet that the engine will not have to be pulled off the aircraft for overhaul during the remaining life of the aircraft.
These factors will be spelled out in the contract. The contractor is not going to sign up for an open ended promise that you’ll never have to pull an engine off a B52, But it will guarantee a certain Time between Overhaul (TBO), perhaps an average per engine, That effectively means the engine will never have to be overhauled during the remaining life of the aircraft.
I think Kelly in Avon was a maintainer, he might have more insight into this, but I was an acquisition guy for a while and this is kind of how these things play out in a contract.
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