B-52s to be re-engined by Rolls Royce!

[IndyFan]

Does everyone poo-pooing Rolls Royce forget what may be the biggest military aviation collaboration in history? I've already mentioned the many other US Military machines powered by Rolls or Rolls/Allison partnerships over the years, and remember, Rolls now owns ALL of Allison Engine Company's tech and resources.

C-130, A7D/E Corsair, P-3, C-2, E3, V-22, F-35B, a myriad of helicopters, and more. But I'll give you a hint on the big one. And we should all be glad and thankful for it......

 

[ekrampitzjr]

The 90–year lifespan sounds incredible, but there is a precedent of sorts.

After the space shuttle orbiter Endeavour was completed and went into service in the early 1990s, NASA had had vague plans to use the orbiter fleet until about 2030, which would have been 50 years after Columbia was built. Endeavour was the replacement for Challenger, lost in 1986. The loss of Columbia on 1 February 2003 killed those plans, and the shuttle fleet was retired after the last mission in 2011. You might think, so what? But that's 50 years on a manned space vessel, not just an aircraft.

 

[y_p_w]

Absolutely. Rolls Royce is a major defense contractor with significant operations in the US, not to mention its US roots. Take a look at their contribution to the F-35B. There would not be an F-35B without Rolls Royce. The lift fan was designed, developed, and is manufactured in Indianapolis, Indiana. Same with engines for the Osprey and C-130, which are the backbone of theater lift capability. Then there's the E2 Hawkeye, and helicopter engines, as well.

And there is much more to it than just installing commercial engines into a military aircraft. The engines will be "militarized," which involves significant engineering to meet various military criteria, particularly in the area of engine controls, but I'm sure in many other areas, as well.

Would it really need to be "militarized" for anything other than the controls and the design of the nacelles? A B-52 is really more like a cargo plane designed to drop its cargo in anger. I thought the primary goal here was to find something that didn't really need much modification, and where commonality with a commercial engine would reduce acquisition and maintenance costs.

There are "military" aircraft where the engines aren't any different than the civilian equivalent other than the paint job. Like the KC-10 and various VIP transport aircraft.

Didn't RR just buy Allison from GM to start their American operations?

 

[IndyFan]

Would it really need to be "militarized" for anything other than the controls and the design of the nacelles? A B-52 is really more like a cargo plane designed to drop its cargo in anger. I thought the primary goal here was to find something that didn't really need much modification, and where commonality with a commercial engine would reduce acquisition and maintenance costs.

There are "military" aircraft where the engines aren't any different than the civilian equivalent other than the paint job. Like the KC-10 and various VIP transport aircraft.

Didn't RR just buy Allison from GM to start their American operations?

I'm unfamiliar with the details but I believe there is much more to it and some of it may be classified. I'll leave it to @Astro14 or someone else to speak to more detail on what it means. But my friend who is an engineer on this project said there was a great deal of work to do to militarize the engine. I'm sure there is much to which he is not permitted to speak. I'd bet one item to do is to shield it from electromagnetic pulse.

While the B-52's flight profile is somewhat like a cargo plane, it is, in fact, a combat aircraft, and I'm sure some things relate to that, as well.

 

[Danno]

Would it really need to be "militarized" for anything other than the controls and the design of the nacelles? A B-52 is really more like a cargo plane designed to drop its cargo in anger. I thought the primary goal here was to find something that didn't really need much modification, and where commonality with a commercial engine would reduce acquisition and maintenance costs.

There are "military" aircraft where the engines aren't any different than the civilian equivalent other than the paint job. Like the KC-10 and various VIP transport aircraft.

Didn't RR just buy Allison from GM to start their American operations?

Redundancies would be my go to on military spec changes , such as fuel supply lines, engine controls and fire suppression.
All important things if you are 3,000 miles from a friendly airbase.
Airliners should have much less distance to travel in case of an engine issue.

 

[Jetronic]

You'd need redundant pilots and cockpits. The lead built into sam targeting means they will often explode near the cockpit.

 

[Owen Lucas]

The original engines are 17,000 lb thrust per engine thus 34,000 per pair. That can now be realized with a single engine. Previous plans (which never got budget approval) were to use 4 engines.

Awesome, the extra unused pod can be used as a new attachment point for bombs.

 

[javacontour]

Awesome, the extra unused pod can be used as a new attachment point for bombs.

I was thinking laser beams.

 

[y_p_w]

Redundancies would be my go to on military spec changes , such as fuel supply lines, engine controls and fire suppression.
All important things if you are 3,000 miles from a friendly airbase.
Airliners should have much less distance to travel in case of an engine issue.

I'd think the redundancy is that they have 8 engines. Maybe they build it with slightly different materials, but they certainly wouldn't be needed to meet performance requirements.

The range of a 777 on two engines is longer than that of a B-52, although it might not be expected to stay in the air as long. However, these new engines will extend the current range.

 

[y_p_w]

I'm unfamiliar with the details but I believe there is much more to it and some of it may be classified. I'll leave it to @Astro14 or someone else to speak to more detail on what it means. But my friend who is an engineer on this project said there was a great deal of work to do to militarize the engine. I'm sure there is much to which he is not permitted to speak. I'd bet one item to do is to shield it from electromagnetic pulse.

While the B-52's flight profile is somewhat like a cargo plane, it is, in fact, a combat aircraft, and I'm sure some things relate to that, as well.

You'd be surprised what a cargo or passenger plane could do. Not sure if Astro can identify the F-14 at the beginning of the video.

 

[kschachn]

Awesome, the extra unused pod can be used as a new attachment point for bombs.

There is no unused pod.

 

[IndyFan]

The look of the BUFF will change a bit with this upgrade, as well. The IR and camera bulges below the nose will be removed. The Sniper pod has taken over that function, so they are not used now.

 

[Dinoburner]

Gonna share my B52 memories that no one else cares about (old person syndrome). I started my career in the mid 70's in Michigan's eastern upper peninsula, less than 5 miles away from Kincheloe Air Base and 2 hours away from K.I. Sawyer Air Base, both SAC units. I was living the dream, often working in remote forest areas, only to have huge B52's occasionally rumble directly overhead so low that one imagined they could see the pilots! Very magnificent!

Interesting

 

[mark pruett]

So when that article mentioned a 90 year life cycle, they were referring to the program itself, and not individual aircraft.

So the 52Hs from that time, are still flying?

Pretty sure they mean the actual airframes themselves, not the program. All the B-52s in service are from the early 60s or earlier.

That F-130 engine they're re-engining them with is a military variant of the Rolls Royce BR700 commercial turbofan that powers a lot of the Gulfstream business jets and the Boeing version of the MD-80 (the Boeing 717).

They're probably a LOT more efficient than the TF-33 engines it currently has, and keeping the eight-engine configuration likely means that they won't have to totally rework all the flight control systems, cockpit controls, or retrain the pilots nearly so much.

 

[wpod]

Back about '88-'89 when I was at Boeing we proposed a 4-engine refit for the B-52 with GE or P&W engines that used less fuel, but of course provided more thrust, but It was rejected by the AF.

Was that the engine types used on the 747?

 

[tom slick]

RR also supplies all C-130 engines and bought Allison decades ago.

 

[y_p_w]

Was that the engine types used on the 747?

I think that would have been way too much thrust. And it probably wouldn't be a great idea because it was physically designed for those small engines.

Here's a photo of someone working on a TF33 from a B-52 (apologies if it looks pixelated):

And someone working on a General Electric CF6:

 

[mark pruett]

Pretty sure they mean the actual airframes themselves, not the program. All the B-52s in service are from the early 60s or earlier.

That F-130 engine they're re-engining them with is a military variant of the Rolls Royce BR700 commercial turbofan that powers a lot of the Gulfstream business jets and the Boeing version of the MD-80 (the Boeing 717).

They're probably a LOT more efficient than the TF-33 engines it currently has, and keeping the eight-engine configuration likely means that they won't have to totally rework all the flight control systems, cockpit controls, or retrain the pilots nearly so much.

The other advantage of the F-130 engine is that it has VERY similar thrust to the TF-33 engines already on the B-52.

So basically the same thrust, a similar size, similar number, etc... It's probably as close to a drop-in replacement as there is for a 60 year old aircraft. And with a significant advantage in fuel consumption and maintainability as well; the F-130 are already in USAF use for some of the VIP aircraft (C-37 transport/Gulfstream V) and the E-11 BACN, and in wide commercial use as well.

I'm not seeing any real downsides here...

 

[kschachn]

That F-130 engine they're re-engining them with is a military variant of the Rolls Royce BR700 commercial turbofan that powers a lot of the Gulfstream business jets and the Boeing version of the MD-80 (the Boeing 717).

The 717 is not the "Boeing version of the MD-80", it was developed by McDonnell Douglas as the MD-95 and is derived from the DC-9 not the MD-80.

 

[y_p_w]

The 717 is not the "Boeing version of the MD-80", it was developed by McDonnell Douglas as the MD-95 and is derived from the DC-9 not the MD-80.

Those are all part of the DC-9 family. I don't know if there's any way to say they don't all build upon later generations.