Rolls Royce win B52 re-engine contract

[Trevatanus]

I am sure there will be some infighting and appeals etc, and obviously RR North America is a US Co, but they have won the B52 Re-engine contract
https://www.airforcemag.com/rolls-royce-wins-b-52-...

[Leon R]

Genuinely surprised the CF34-10E didn't get chosen for this.

Seemed like the best option.

[Eric Mc]

I'm sure the relevant Senators will fight their respective corners.

[aeropilot]

Trevatanus said:

I am sure there will be some infighting and appeals etc, and obviously RR North America is a US Co, but they have won the B52 Re-engine contract
https://www.airforcemag.com/rolls-royce-wins-b-52-...

What is now RR N/A is actually the old Allison Engine Company......which for most of its life was owned by General Motors, before being sold by them and acquired by RR 25 years ago.......so apart from the name it's about as American as apple pie.

[LotusOmega375D]

I’ve just done the math (sic) and that works out at US$ 4 million per engine, fitted. Isn’t that extremely cheap?

[Eric Mc]

aeropilot said:

What is now RR N/A is actually the old Allison Engine Company......which for most of its life was owned by General Motors, before being sold by them and acquired by RR 25 years ago.......so apart from the name it's about as American as apple pie.

Wasn't the Allison engine fitted to the A7 Corsair II essentially a Rolls Royce Spey?

[AlexS]

Eric Mc said:

aeropilot said:

What is now RR N/A is actually the old Allison Engine Company......which for most of its life was owned by General Motors, before being sold by them and acquired by RR 25 years ago.......so apart from the name it's about as American as apple pie.

Wasn't the Allison engine fitted to the A7 Corsair II essentially a Rolls Royce Spey?

And the F130 that is going into the B52 is a militarised BR725.

[nikaiyo2]

LotusOmega375D said:

I’ve just done the math (sic) and that works out at US$ 4 million per engine, fitted. Isn’t that extremely cheap?

Not when you buy 650 at a time :P

[andy97]

nikaiyo2 said:

LotusOmega375D said:

I’ve just done the math (sic) and that works out at US$ 4 million per engine, fitted. Isn’t that extremely cheap?

Not when you buy 650 at a time :P

And probably spares are extra.

[aeropilot]

andy97 said:

nikaiyo2 said:

LotusOmega375D said:

I’ve just done the math (sic) and that works out at US$ 4 million per engine, fitted. Isn’t that extremely cheap?

Not when you buy 650 at a time :P

And probably spares are extra.

The 650 includes the spare engines.

[AlexS]

Leon R said:

Genuinely surprised the CF34-10E didn't get chosen for this.

Seemed like the best option.

Out of the competitor engines the F130 was the closest match to the originals in terms of diameter, CofG and thrust, making the airframe integration easier.

[eldar]

AlexS said:

Out of the competitor engines the F130 was the closest match to the originals in terms of diameter, CofG and thrust, making the airframe integration easier.

Don't repeat the 737 Max problem?

[AlexIT]

So they'll keep the 4 twin nacelles?

Are these high-bypass fans, if so any idea what's their front section compared to current ones?

[aeropilot]

AlexIT said:

So they'll keep the 4 twin nacelles?

Are these high-bypass fans, if so any idea what's their front section compared to current ones?

Very similar.

The engine are going to be a mil version of the engines used in current Gulfstream G650 and Boeing 717's etc.

[Eric Mc]

eldar said:

Don't repeat the 737 Max problem?

Shouldn't be an issue. The underlying problem with the Max was that there was insufficient ground clearance between the bottom of the engine nacelles and the ground. This required the engines to be mounted further forward of the wing and placed higher than on the earlier 300 to 900 families.
The 737 has quite short undercarriage legs which places the fuselage and wings close to the ground.

That is not the case with the B-52.

Edited by Eric Mc on Monday 27th September 16:20

[AlexIT]

aeropilot said:

Very similar.

The engine are going to be a mil version of the engines used in current Gulfstream G650 and Boeing 717's etc.

Thanks

[Leon R]

AlexS said:

Leon R said:

Genuinely surprised the CF34-10E didn't get chosen for this.

Seemed like the best option.

Out of the competitor engines the F130 was the closest match to the originals in terms of diameter, CofG and thrust, making the airframe integration easier.

Was it? I thought the Passport 20 was the most similar.

[eldar]

Eric Mc said:

eldar said:

Don't repeat the 737 Max problem?

Shouldn't be an issue. The underlying problem with the Max was that there was insufficient ground clearance between the bottom of the engine nacelles and the ground. This required the engines to be mounted further forward of the wing and placed higher than on the earlier 300 to 900 families.
The 737 has quite short undercarriage legs which places the fuselage and wings close to the ground.

That is not the case with the B-52.

Edited by Eric Mc on Monday 27th September 16:20

Thanks

[AlexS]

aeropilot said:

AlexIT said:

So they'll keep the 4 twin nacelles?

Are these high-bypass fans, if so any idea what's their front section compared to current ones?

Very similar.

The engine are going to be a mil version of the engines used in current Gulfstream G650 and Boeing 717's etc.

The Boeing 717 (MD95) is the BR715, this is the BR725.

[GliderRider]

The USAF looked at re-engining B-52s in 1982 and 1996. In the latter, the plan was to use leased RB211-535 engines, as used on Boeing 757s. The failure to go ahead at that time was due firstly to a resistance to leased combat assets, and secondly due to a miscalculation which failed to take into account the vastly increased cost of fuel from an air-to-air tanker ($17.50 vs $1.25/gallon).

Had this scenario gone ahead, each pair of TF33s would have been replaced by one RB211-535. In the current plan, each pod will still have two engines, as it avoids further fin/rudder modifications to account from the increased offset drag from a non-functioning single high bypass fan.

This is a link to the text of Bill Sweetman's 2014 Aviation Week article, which is otherwise behind a paywall. B-52 Re-engine Resurfaces As USAF Reviews Studies - Bill Sweetman