Boeing B-52 Re-engine News and Discussion Thread

Flighty · Sat Jun 02, 2018 6:43 pm

I was just watching YouTube and there was an ad (not signed by any OEM or anybody) advocating for a new B-52 re-engine program to increase range and orbit time above the battlefield. Had some fairly professional animations.

Who is doing this? Is this some consultant trawling for business? It wasn’t signed by Boeing or anybody.

TheFlyingDisk · Sun Jun 03, 2018 12:52 pm

Is it this video? If it is, then obviously it's Boeing

https://www.youtube.com/watch?v=vHdIRwKtnig

Francoflier · Sun Jun 03, 2018 3:11 pm

To the untrained eye, re-engining the B-52 seems like a no brainer...
Especially if you consider the potential gains to be had with current generation engines vs. the museum pieces currently hanging off these wings.

But there's always more than meet the eyes. I can't remember the specifics, but the last discussion on the topic was quite interesting and shed light on the underlying complexity of what seems a fairly straightforward project.

That said, whatever these complexities might be, the exponentially growing costs of maintaining and feeding these gas guzzling noise and smoke generators will eventually justify the effort. Especially if the air force plans on keeping these birds in the air another few decades...

washingtonflyer · Sat Aug 18, 2018 5:05 am

Whats the news on this? I heard that there was some consensus that it would be very difficult to re-engine these birds through removing the dual engine pods and replacing a pod with a single engine.

I had head that the leading contenders were the CF/TF-34 (found on the A-10 and larger Embraer series jets) and the Rolls Royce BR-725.

trpmb6 · Mon Aug 20, 2018 2:03 pm

washingtonflyer wrote:
Whats the news on this? I heard that there was some consensus that it would be very difficult to re-engine these birds through removing the dual engine pods and replacing a pod with a single engine.

I had head that the leading contenders were the CF/TF-34 (found on the A-10 and larger Embraer series jets) and the Rolls Royce BR-725.

As has been noted in other B52 re-engine threads it is not possible to replace the dual engine pods with a single engine due to not enough rudder control under engine out situations.

BR-725 seems like the most likely choice.

keesje · Mon Aug 27, 2018 10:54 am

It's incredible this is becoming a serious business case again. The youngest B52 are 55 yrs old ? Real first gen structure / wing technology. Apparently nothing feasibly can replace the flying gastank economically apart from a new design. It's like reengining a battle ship..

http://www.minotdailynews.com/news/local-news/2018/08/senate-passes-defense-appropriations-bill/

Slug71 · Mon Aug 27, 2018 3:52 pm

Crazy. The money would be better spent on the B-21 and advanced ICBMs IMO.

bigjku · Mon Aug 27, 2018 4:01 pm

Slug71 wrote:
Crazy. The money would be better spent on the B-21 and advanced ICBMs IMO.

It depends. If you just want something to haul a ton of stand-off weapons and/or MALD decoys of various flavors the B-52 will do it far more cheaply. It really depends on how much one spends on the capability.

It’s a lot like the A-10 to me. I don’t mind having some around as long as you don’t break the bank doing it. Just don’t look at them as replacements for modern planes.

trpmb6 · Mon Aug 27, 2018 4:02 pm

Slug71 wrote:
Crazy. The money would be better spent on the B-21 and advanced ICBMs IMO.

Completely different mission profiles, capabilities and costs.

Same reason we still have B-1's flying when we have the perfectly capable B-2.

Ozair · Tue Feb 26, 2019 12:00 am

I expect we will start to get some more concrete info on the respective bids for the B-52 re-engine in coming months such as the below by RR.

Rolls-Royce touts modernised Indiana factory for B-52 engine bid

Rolls-Royce plans to build its F130 turbine at a modernised factory in Indiana if selected by the US Air Force to replace the engines on the service’s fleet of Boeing B-52 bombers.

The USAF programme calls for 650 new engines to help extend the longevity and performance of its aging B-52s. Rolls-Royce says its Indianapolis, Indiana facility is nearing completion of a $600 million modernisation initiative, which would optimise production of an engine in the size class of the F130.

The F130 engine for the B-52 is a variant of the Rolls-Royce BR725 commercial engine and produces 17,000lb-thrust. The F130 series of engines also power USAF aircraft such as the Bombardier E-11A and Gulfstream C-37 aircraft.

“Our ultra-modern, advanced manufacturing facilities in Indianapolis are the perfect location to produce, assemble, and test the Rolls-Royce F130 engine for the US Air Force B-52 programme,” says Tom Bell, Rolls-Royce Defense president. “Rolls-Royce North America continues to invest heavily in advanced manufacturing and technology at our Indianapolis site, making it one of the most efficient and modern facilities anywhere in the aerospace world.”

Indianapolis is the largest Rolls-Royce engineering, design and manufacturing site in the USA, says the company. The manufacturer produces engines for multiple USAF aircraft at the facility, including the C-Lockheed Martin 130J transport, Bell Boeing CV-22 Osprey and Northrop Grumman RQ-4 Global Hawk.

https://www.flightglobal.com/news/artic ... -5-456087/

texl1649 · Tue Feb 26, 2019 1:40 am

In inventory, reliable, made in USA, and 650 ENGINES! Wow, I realize these beasts can be maintained a long time but that is quite a feat if it is pulled off. I’m a bit skeptical it happens though.

Ozair · Sat Mar 02, 2019 9:54 pm

More info on the expected re-engine RFP. trying to do the radar, communications, engine and integrate hypersonic weapons all over the next few years is a very ambitious effort.

The expectation then is that the B-52 will serve into the 2050s, clocking up 100 years!

Air Force About to Release RFP for B-52 Re-Engining Program

The Air Force plans to release a request for proposals for its highly anticipated B-52H re-engining program in March, a senior service official said Feb. 28.

The Air Force is embarking on an effort to outfit its aging fleet of B-52 Stratofortress heavy bombers with new engines that will keep them flying through the 2050s. Each bomber is currently equipped with eight Pratt & Whitney TF33 engines. It is anticipated that the Air Force will procure a total of 650 new systems for the aircraft.

“Last time I checked in we were on track to release within the next month,” Will Roper, assistant secretary of the Air Force for acquisition, technology and logistics, told reporters during the Air Force Association’s Air Warfare Symposium in Orlando, Florida.

Rolls-Royce, Pratt & Whitney and General Electric are expected to compete for the program. A contract award decision is anticipated in fiscal year 2020.

The Air Force may use other transaction authority agreements to help build prototypes of the engines, Roper said.

“Our goal is to get industry working quickly," he said. An OTA agreement would work "well for this kind of program,” he added.

OTAs have become popular contracting mechanisms that can help the government cut through bureaucratic red tape as it pursues new technology.

The first step toward picking a new B-52 engine will be to create a “virtual power model,” Roper said. That will allow the Air Force to work with industry on integration issues with the engine and the aircraft.

Next, similar to how commercial airlines choose engines, the Air Force will look at issues such as fuel efficiency at different altitudes, he said.

Roper noted that the B-52 program in general is a “worry” of his because of the multiple modernization and upgrades efforts that are occurring simultaneously. The bomber first entered service in the 1950s.

There are five major upgrade programs associated with the platform including those addressing the engine, radar and communications suite as well as two hypersonic weapons-related efforts, he said.

“We are going to have to manage that like one mega-program," he said.

http://www.nationaldefensemagazine.org/ ... ng-program

45272455674 · Sun Mar 03, 2019 11:38 am

Ozair wrote:
More info on the expected re-engine RFP. trying to do the radar, communications, engine and integrate hypersonic weapons all over the next few years is a very ambitious effort.

The expectation then is that the B-52 will serve into the 2050s, clocking up 100 years!

Air Force About to Release RFP for B-52 Re-Engining Program

The Air Force plans to release a request for proposals for its highly anticipated B-52H re-engining program in March, a senior service official said Feb. 28.

The Air Force is embarking on an effort to outfit its aging fleet of B-52 Stratofortress heavy bombers with new engines that will keep them flying through the 2050s. Each bomber is currently equipped with eight Pratt & Whitney TF33 engines. It is anticipated that the Air Force will procure a total of 650 new systems for the aircraft.

“Last time I checked in we were on track to release within the next month,” Will Roper, assistant secretary of the Air Force for acquisition, technology and logistics, told reporters during the Air Force Association’s Air Warfare Symposium in Orlando, Florida.

Rolls-Royce, Pratt & Whitney and General Electric are expected to compete for the program. A contract award decision is anticipated in fiscal year 2020.

The Air Force may use other transaction authority agreements to help build prototypes of the engines, Roper said.

“Our goal is to get industry working quickly," he said. An OTA agreement would work "well for this kind of program,” he added.

OTAs have become popular contracting mechanisms that can help the government cut through bureaucratic red tape as it pursues new technology.

A competition I see? Hmm, it should go to protests, appeals, back and forth for so long the current crop of crews will probably all be retired by the time they eventually decide on choosing an engine that ticks all the right political boxes. I guess I'm only just slightly cynical.

The first step toward picking a new B-52 engine will be to create a “virtual power model,” Roper said. That will allow the Air Force to work with industry on integration issues with the engine and the aircraft.

Next, similar to how commercial airlines choose engines, the Air Force will look at issues such as fuel efficiency at different altitudes, he said.

Roper noted that the B-52 program in general is a “worry” of his because of the multiple modernization and upgrades efforts that are occurring simultaneously. The bomber first entered service in the 1950s.

There are five major upgrade programs associated with the platform including those addressing the engine, radar and communications suite as well as two hypersonic weapons-related efforts, he said.

“We are going to have to manage that like one mega-program," he said.

http://www.nationaldefensemagazine.org/ ... ng-program

Channex757 · Mon Mar 04, 2019 2:00 am

The overall rationale for the project is to point at the C-5M and say "Look how well that has worked".

The project to re-engine the Galaxy and also modernise many parts of the aircraft has yielded a superbly updated freight hauler for the USAF. Taking in the B-52 to be re-engined whilst its guts are already open would be a more efficient and cheaper way of doing the same. Add this longer ranged bomber plus the more flexible KC-46 as support would certainly give the USAF the ability to project force even more powerfully and quickly.

I really hope this comes off this time round.

LiegeSilhouette · Mon Mar 25, 2019 5:50 pm

Personally, after reading about the re-engining requirements set by the USAF regarding the B-52, I have concluded that the best engine replacement options for the B-52 would be a non afterburning, non-variable cycle, higher thrust variant of the GE YF120 (used in the Advanced Tactical Fighter), or a non afterburning variant of the GE F136 (used as a Joint Strike Fighter alternative engine). Here's why,

1. The GE YF120 and F136 are low bypass turbofans that are around the same size (slightly smaller in diameter) and weight as the JT3D engines used in the B-52, making them ideal replacements that can be fitted to the engine pylons with minimal retrofitting.
2. The GE YF120 and F136 are the most advanced and powerful low bypass turbofans that GE has ever manufactured, reducing maintenance costs, aerial refueling frequency, and increasing fuel efficiency compared to the JT3D, since they produce more power for every amount of fuel burnt and produce less smoke and pollution in their exhaust. The GE YF120 uses 40% fewer parts than the F110, which would increase the durability of the engine compared to the F118 (the non afterburning derivative of the F110 used in the B-2 Spirit). Although redundant, the extra power of the YF120 and F136 can be useful during certain combat circumstances, and since the maximum power of the JT3D would only be slightly over half the maximum dry military power of the YF120 and F136, flying the B-52 using the same power as the maximum power as the JT3D on the YF120 and F136 would save fuel and put less stress on the engines, potentially reducing maintenance costs.
3. As turbofan engines, the YF120 and F136 should produce significantly less noise pollution than JT3D engines, making them more suitable for low level flight.

mmo · Mon Mar 25, 2019 9:09 pm

LiegeSilhouette wrote:
Personally, after reading about the re-engining requirements set by the USAF regarding the B-52, I have concluded that the best engine replacement options for the B-52 would be a non afterburning, non-variable cycle, higher thrust variant of the GE YF120 (used in the Advanced Tactical Fighter), or a non afterburning variant of the GE F136 (used as a Joint Strike Fighter alternative engine). Here's why,

How are you going to handle the rudder issue?

Ozair · Mon Mar 25, 2019 9:52 pm

mmo wrote:
LiegeSilhouette wrote:
Personally, after reading about the re-engining requirements set by the USAF regarding the B-52, I have concluded that the best engine replacement options for the B-52 would be a non afterburning, non-variable cycle, higher thrust variant of the GE YF120 (used in the Advanced Tactical Fighter), or a non afterburning variant of the GE F136 (used as a Joint Strike Fighter alternative engine). Here's why,

How are you going to handle the rudder issue?

Why would you use the F136 or YF120 given neither of those engines is in production? If you were going to go down that route then the aircraft, if the engineering issues it would bring as already mentioned above was valid, could use the F135, probably the non-afterburning variant likely being built for the B-21.

LiegeSilhouette · Mon Mar 25, 2019 11:15 pm

Ozair wrote:
mmo wrote:
LiegeSilhouette wrote:
Personally, after reading about the re-engining requirements set by the USAF regarding the B-52, I have concluded that the best engine replacement options for the B-52 would be a non afterburning, non-variable cycle, higher thrust variant of the GE YF120 (used in the Advanced Tactical Fighter), or a non afterburning variant of the GE F136 (used as a Joint Strike Fighter alternative engine). Here's why,

How are you going to handle the rudder issue?

Why would you use the F136 or YF120 given neither of those engines is in production? If you were going to go down that route then the aircraft, if the engineering issues it would bring as already mentioned above was valid, could use the F135, probably the non-afterburning variant likely being built for the B-21.

During the Advanced Tactical Fighter, test pilots who flew the YF120 powered YF-23 reported that the jet supercruised faster than the YF119 powered version, indicating that the YF120 was a lot more powerful than the F119, not to mention that the YF120 was considerably more technologically advanced than the F119. The F135, on the other hand was plagued with problems, such as overheating, cost overruns, turbine failures, and durability issues. These problems with the F135 is what drove the Pentagon to search for an alternate engine for the F-35, which led to the creation of the F-136. Like the YF120, the F-136 was considerably more advanced than its competitor, the F135.

texl1649 · Tue Mar 26, 2019 1:06 am

The appeal to re-engine the remaining B-52’s circles around maintenance and life cycle costs, not performance or anything else. As such, the Rolls engine that is in inventory and is the same size makes the most sense by far. A 25 year old developmental engine that didn’t win or make it to production has zero chance of even being considered in this program.

Ozair · Tue Mar 26, 2019 2:10 am

LiegeSilhouette wrote:
Ozair wrote:
mmo wrote:

How are you going to handle the rudder issue?

Why would you use the F136 or YF120 given neither of those engines is in production? If you were going to go down that route then the aircraft, if the engineering issues it would bring as already mentioned above was valid, could use the F135, probably the non-afterburning variant likely being built for the B-21.

During the Advanced Tactical Fighter, test pilots who flew the YF120 powered YF-23 reported that the jet supercruised faster than the YF119 powered version, indicating that the YF120 was a lot more powerful than the F119, not to mention that the YF120 was considerably more technologically advanced than the F119. The F135, on the other hand was plagued with problems, such as overheating, cost overruns, turbine failures, and durability issues. These problems with the F135 is what drove the Pentagon to search for an alternate engine for the F-35, which led to the creation of the F-136. Like the YF120, the F-136 was considerably more advanced than its competitor, the F135.

A bit of revisionist history? The F136 was not developed as an alternative due to F135 issues, both engines were being developed in tandem to potentially provide an alternative propulsion unit similar to the F100/F110 and generate cost savings or at least leverage on P&W. In opposition to your claims is the intent of the USDOD to cancel the F136 from FY2007 all the way until they finally succeeded in 2011. Yes that was primarily driven by cost reduction but clearly there were not enough major concerns with the F135 to keep a second engine in play.

There is a very good document that outlines the history of the F135 and F136 here, https://fas.org/sgp/crs/weapons/RL33390.pdf from the Congressional Research Service

Sure the F135 has had a couple of issues but nothing so earth chattering that development was stopped. The F136 never flew in an aircraft and given it hasn’t been flown or used since would seem pointless to continue with that engine. GE’s opportunity to get into the F-35 will come out of the AETP (the GE XA100) which will see a new engine competition in the mid 2020s for the F-35 fleet, possibly the B-21 and the PCA. Either way, progressing forward with the F136 to power the B-52 is a pointless exercise as that engine is dead, as would be trying to revive the YF120, an even more buried engine.

Ozair · Mon Sep 16, 2019 1:29 am

The USAF is hoping to issue an RFP for the B-52 replacement engine by the end of this year, contract award a year later and then flight tests in the 2023-24 timeframe.

US Air Force nears battle over next B-52 engine

After several months of delays, the U.S. Air Force is hoping to release a request for proposals for new B-52 bomber engines by the end of 2019, once the service gets the chance to solidify its solicitation and answer congressional concerns.

But at Barksdale Air Force Base in Louisiana, B-52 maintainers are hungry for new motors that will hopefully lessen the time it takes to diagnose and fix engine problems.

“If I was to prioritize the systems from a maintainer’s point of view, in my personal opinion — not the Air Force’s obviously — but [replacing] the engines first and foremost” would have the most positive impact on the maintenance community, said Lt. Col. Tiffany Arnold, 2nd Maintenance Squadron commander. Arnold spoke with journalist and Defense News contributor Jeff Bolton during a visit to Barksdale AFB.

Each B-52 uses eight TF33 engines to fly, which means maintainers spend a lot of time ensuring each engine functions properly. And when more than one engine needs repairs, that entails more work for the personnel that are already performing multiple assessments, Arnold said.

...

https://www.defensenews.com/smr/global- ... 52-engine/

Nomadd · Mon Sep 16, 2019 4:56 am

I use to have WWII class tube radios that cost a fortune to maintain in the USCG. I started hiding $400 commercial UHF vehicle radios in the huge cabinets and called it maintenance.
Point being, spending more to maintain the old engines than new ones would cost wouldn't surprise me at all. Nobody in the chain wants to give up their job by making things more efficient.

Ozair · Tue Sep 24, 2019 2:27 am

RR are certainly keen on winning this contract, should it finally eventuate, and looks to be a significant investment of their own funds into this early testing.

Rolls-Royce F130 engine for B-52 completes early testing

Rolls-Royce has completed early engine tests with the F130, the engine which will be offered for the US Air Force B-52 Commercial Engine Replacement Program.

Full-engine tests were completed recently at Rolls-Royce facilities in Indianapolis, US, confirming the engine design and performance are a perfect fit for the B-52 aircraft say Rolls-Royce.

In addition to full-engine tests, Rolls-Royce has already compiled more than 50,000 hours of digital engineering time to further develop and refine the F130 for the B-52.

...

https://ukdefencejournal.org.uk/rolls-r ... y-testing/

texl1649 · Tue Sep 24, 2019 12:38 pm

It is a remarkable opportunity. I would think due to the quantity (and likely 40 years of follow on support) this is probably the largest military engine contract, outside of perhaps the F-135 one, in 20 years. It’s not the priciest per engine, sure, but 650 engines is still more than any other I can recall. Whilst RR own the program outright now, the present manufacturing is still in Germany (from the BMW joint venture). Has a (partial) German design ever powered a US combat aircraft?

https://www.rolls-royce.com/products-an ... /f130.aspx

BlueJohn75 · Wed Sep 25, 2019 11:35 am

If you think about how recent big USAF engine contracts have gone, it would only seem reasonable that RR get this gig..

GE got to sell a ton of (old tech) CF-6s for the C5-M program, then PW saved their (old tech) PW4000 line with the KC-46 selection.

RR have been in the mix forever for the B-52 with various options, so I hope they get it.

Armadillo1 · Thu Sep 26, 2019 8:16 am

from outside point of view its looks ridiculous.
ok, you want to replace jurassic engines. you talks about from 80 or earlie to replace 8-to-4
now its going to replace to 8 really expensive ones while frames itself to old to some rough action like low altitude rush.

Ozair · Thu Sep 26, 2019 9:42 am

Armadillo1 wrote:
from outside point of view its looks ridiculous.
ok, you want to replace jurassic engines. you talks about from 80 or earlie to replace 8-to-4
now its going to replace to 8 really expensive ones while frames itself to old to some rough action like low altitude rush.

The engine upgrade for the B-52 will likely pay for itself in reduced fuel and maintenance costs while also improving overall capability and availability.

The mission of the B-52 is now medium to high altitude stand off weapon delivery with the occasional JDAM/dump bomb mass drop, it's low altitude days are long behind it.

Armadillo1 · Thu Sep 26, 2019 9:52 am

Ozair wrote:
Armadillo1 wrote:
from outside point of view its looks ridiculous.
ok, you want to replace jurassic engines. you talks about from 80 or earlie to replace 8-to-4
now its going to replace to 8 really expensive ones while frames itself to old to some rough action like low altitude rush.

The engine upgrade for the B-52 will likely pay for itself in reduced fuel and maintenance costs while also improving overall capability and availability.

The mission of the B-52 is now medium to high altitude stand off weapon delivery with the occasional JDAM/dump bomb mass drop, it's low altitude days are long behind it.

thank you cap

pls compare with 4 bigger engines, not with TF-33. and answer why to install twice number of most expensive engines on planet.

texl1649 · Thu Sep 26, 2019 10:32 am

Armadillo1 wrote:
Ozair wrote:
Armadillo1 wrote:
from outside point of view its looks ridiculous.
ok, you want to replace jurassic engines. you talks about from 80 or earlie to replace 8-to-4
now its going to replace to 8 really expensive ones while frames itself to old to some rough action like low altitude rush.

The engine upgrade for the B-52 will likely pay for itself in reduced fuel and maintenance costs while also improving overall capability and availability.

The mission of the B-52 is now medium to high altitude stand off weapon delivery with the occasional JDAM/dump bomb mass drop, it's low altitude days are long behind it.

thank you cap

pls compare with 4 bigger engines, not with TF-33. and answer why to install twice number of most expensive engines on planet.

The rudder would be a big issue going to a quad configuration.

http://www.airpowerstrategy.com/2016/11 ... w-engines/

Armadillo1 · Thu Sep 26, 2019 10:56 am

thank you, interesting.

bikerthai · Thu Sep 26, 2019 5:37 pm

texl1649 wrote:
The rudder would be a big issue going to a quad configuration.

Going to a quad configuration would increase the complexity of the change up through the Engine mounts and to the wings. Limiting the change to 8 smaller engine enable you to limit the change up to the engine mount (aside from wiring changes relating to new control system).

Increasing thrust and could cause other issue as noted by Ozair. Not only do you have to worry about the rudder, but also the trim and flight dynamics as shown by the MAX debacle.

bt

Ozair · Thu Sep 26, 2019 9:25 pm

Armadillo1 wrote:
Ozair wrote:
Armadillo1 wrote:
from outside point of view its looks ridiculous.
ok, you want to replace jurassic engines. you talks about from 80 or earlie to replace 8-to-4
now its going to replace to 8 really expensive ones while frames itself to old to some rough action like low altitude rush.

The engine upgrade for the B-52 will likely pay for itself in reduced fuel and maintenance costs while also improving overall capability and availability.

The mission of the B-52 is now medium to high altitude stand off weapon delivery with the occasional JDAM/dump bomb mass drop, it's low altitude days are long behind it.

thank you cap

pls compare with 4 bigger engines, not with TF-33. and answer why to install twice number of most expensive engines on planet.

Others have stated but the best resource is this earlier thread, viewtopic.php?f=10&t=1370415&hilit=%26quot%3Bb+52%26quot%3B

mmo · Fri Sep 27, 2019 5:09 am

Ozair wrote:

The rudder would be a big issue going to a quad configuration.

Putting 4 engines instead of 8 would be so expensive the B-52 would have to fly at least another 100 years to get any payback. As it is, the H is barely able to handle all engines out on one side due to the rudder. Remember the H was built as a stop gap measure and the G was supposed to be the final version. But due to the change to low level tactics the H was introduced as a "quick fix" as the earlier models were not able to handle the low level mission. So, any change such as that would require a complete redesign of the rudder to handle the worst-case scenario of 4 engines out on one side. That would be a major design task resulting in a completely new rudder design and most likely a completely new 47 section structure.

The frame has plenty of life left on it even though it flew low level for many years. So fatigue is not an issue. The major structural issue facing the H model is the upper wing skin which can only last until 2040. So, I assume if the plan is to fly it until 2050 or beyond then that issue has to be addressed. While I haven't seen anything specific, I assume it will be done given all the other upgrades planned.

If the B-1 is phased out earlier than planned due to the high cost maintaining it, I would expect to see the H model around until at least 2060.

LightningZ71 · Fri Sep 27, 2019 1:06 pm

Long story short, going with 8 engines of similar size, weight, and thrust rating simplifies the whole project as much as possible to keep the R&D costs of it down to the lowest attainable level. No matter what they choose, the project will still require a massive investment in integrating the FADEC systems of the newer engines into the Flight Deck of the B-52. That has been a big part of what has pushed this project off into the future over and over. They finally seem to be getting to the point that they are willing to make that investment.

As for what the improvements bring to the table, the biggest gain is the range without requiring a refueling. The B-52 will gain upwards of 50% more unrefueled range, and, will have to loft less fuel weight for shorter trips than before, reducing wear and tear on the frame as well as saving money that would be spent on fuel in the first place. This isn't just an operational cost savings, its an improvement in operational flexibility. The B-52 will be able to loiter longer (though, that wasn't really a big issue before) without needing to refuel. It will be able to ferry farther without requiring tanker assets. Overall, with the issues that the USAF has been having with tankers with respect to the KC-47, having less of a need for tankers going forward will be a big win for them. This will also allow any tankers used to stay farther away from enemy air space as well, which is more and more important with the advent of very long range SAMs and A2A missiles.

kc135topboom · Thu Oct 03, 2019 11:49 am

The USAF claims the B-52H could fly into the 2050s if it is reengined, at least that is what they are telling Congress. I estimate the cost per bomber with new engines, related hardware, software, avionics, radar upgrades and training for aircrews and ground maintainers will cost in the neighborhood of $100MILLION. Multiply that by 76 airplanes that is $7.6BILLION add in spares and we are talking around $8BILLION.

That is not counting the now required upper wing reskin that mmo reminded us about to fly into the 2050s. This will be another $25MILLION per airplane or $1.9BILLION for the fleet. That is some $9.5BILLION, not counting costs overruns.

Remember the total fly away cost to reengine and upgrade the KC-135A to the KC-135R was $29MILLION per tanker.

The 'new' bomber will most likely be redesignated as the B-52J. That will render all the current B-52Hs and B-52Gs stored at AMARG next to useless as far as parts donors are concerned. Yes, a few structural parts and things like landing gear can still be used, but almost nothing else. Yes, there are about 20 B-52Hs currently stored at AMARG with 2 having been returned to service. But with the "J" model upgrades, no "H" models would be capable to back fill attrition loses. So the fleet of 76 will eventually be reduced to some unknown number.

In my opinion we could better use that money to upgrade the B-2 fleet, fix the KC-46, fix the F-35, or put into the B-21 project..

texl1649 · Thu Oct 03, 2019 2:05 pm

kc135topboom wrote:
The USAF claims the B-52H could fly into the 2050s if it is reengined, at least that is what they are telling Congress. I estimate the cost per bomber with new engines, related hardware, software, avionics, radar upgrades and training for aircrews and ground maintainers will cost in the neighborhood of $100MILLION. Multiply that by 76 airplanes that is $7.6BILLION add in spares and we are talking around $8BILLION.

That is not counting the now required upper wing reskin that mmo reminded us about to fly into the 2050s. This will be another $25MILLION per airplane or $1.9BILLION for the fleet. That is some $9.5BILLION, not counting costs overruns.

Remember the total fly away cost to reengine and upgrade the KC-135A to the KC-135R was $29MILLION per tanker.

The 'new' bomber will most likely be redesignated as the B-52J. That will render all the current B-52Hs and B-52Gs stored at AMARG next to useless as far as parts donors are concerned. Yes, a few structural parts and things like landing gear can still be used, but almost nothing else. Yes, there are about 20 B-52Hs currently stored at AMARG with 2 having been returned to service. But with the "J" model upgrades, no "H" models would be capable to back fill attrition loses. So the fleet of 76 will eventually be reduced to some unknown number.

In my opinion we could better use that money to upgrade the B-2 fleet, fix the KC-46, fix the F-35, or put into the B-21 project..

The USAF selected the CFM56's for the KC-135 during the Carter administration in 1979 for goodness sakes, though; cost isn't particularly analogous. We all know it would cost an utter fortune today for the USAF to truly replace the flying arsenal capability the 75 Buff's provide. The B-21 nor the B-2 are remotely comparable in capability (or cost per hour, likely).

If anything, the agonizing slowness of finally bringing the KC-46 into the fleet in numbers justifies continuing to maintain the B-52 and upgrade as necessary since we realize it takes the USAF something like 30 years to procure a large aircraft fleet now, even if it's just a commercial derivative. The parts will still be largely common with the H model, and the BUFF sorely needs some of the upgrades the stratotanker has been/is being given over the years avionics-wise.

https://www.thedrive.com/the-war-zone/1 ... ss-cockpit

kc135topboom · Sat Oct 05, 2019 8:13 pm

texl1649, the last KC-135 to be modified to a "R" model was a "E" model in 2006. It cost just $29MILLION in 2006 dollars. The RC-135s began being modified with the F-108 engines in 2003 and was completed in 2009. The RC costs were higher because there were some mission equipment changed out and/or upgraded at the same time. I don't recall the costs of the RC-135 reengine program but I think it was around $60MILLION, fly away with the new mission equipment, which varied by the RC model being modified.

So, I think my estimate for the B-52 reengine program of about $100MILLION plus another $25MILLION for the upper skin replacement is fairly accurate.

william · Fri Nov 08, 2019 3:39 pm

I thought for sure there would be performance advantages to re engine the BUFF.

http://www.airpowerstrategy.com/2016/11 ... w-engines/

Others claim a new engine would make the B‑52 more reliable. Again, not true. Hard as it may be to believe, the B‑52 is one of the most reliable aircraft in the USAF inventory. Mission capable rates vary by year, but the B‑52 has not fallen below 70% mission capable for decades, while the B‑1B and B‑2A have never been above 70%. 2016 Mission Capable Rates put the B‑52 at 72%, B‑1B at 46%, and the B‑2A at 55%. Understand, the engines have nothing to do with the mission capable rates of any of these aircraft. The low rates for the B‑1B and B‑2A are not engine related, nor is the high rate for the B‑52. The point is, the B‑52 is already the most reliable bomber the USAF has in its inventory. The limiting factor for all the bombers is electrical and avionics related. There is a case to be made for increasing the reliability of all the bombers, but engines will not increase or decrease that reliability. If there is money to be spent on reliability, that money does not need to be spent on B‑52 engines.

Still others make statements concerning the B‑52’s lifespan and how new engines could let it fly far past 2050. These claims are also false. The limiting factor on the B-52 service life has always been, and remains, the upper wing surface. The B‑52 upper wing surface was designed to give the aircraft a 35,000 hour service life. The reason the H-model B‑52 remains in service today is because it sat alert for decades and did not fly nearly as much as its predecessors. In terms of hours flown, the B‑52 is middle-aged. However, that timeline will have an end state. The current projections of B‑52s flying to 2040 are at current usage rates with current hours on its current wings. If the B‑52 flies past 2050 in bulk, it will need to resurface the wings, new engine or not.

Granted, a new engine can and will increase range and endurance but these performance increases are a by-product of engine efficiency. A program dedicated to increasing these capabilities does not make sense. Some engineering studies have stipulated that better engines could increase the unrefueled range of the B-52 by as much as 45%,[19] however B‑52 range is already the most impressive in the USAF fleet. The B-52 has many problems, however range and endurance are not among them. A program designed to fix non-existent problems does not need to exist.

For these reasons, a B‑52 re-engine program should not strive to increase performance in any way. Performance may increase in some areas, but it should not be the objective of the program. Similarly, fuel savings should not be the objective either. The only objective for a B‑52 re-engine that makes any sense is to reduce overall cost for the USAF.

nycbjr · Fri Nov 08, 2019 3:48 pm

william wrote:
I thought for sure there would be performance advantages to re engine the BUFF.

http://www.airpowerstrategy.com/2016/11 ... w-engines/

Others claim a new engine would make the B‑52 more reliable. Again, not true. Hard as it may be to believe, the B‑52 is one of the most reliable aircraft in the USAF inventory. Mission capable rates vary by year, but the B‑52 has not fallen below 70% mission capable for decades, while the B‑1B and B‑2A have never been above 70%. 2016 Mission Capable Rates put the B‑52 at 72%, B‑1B at 46%, and the B‑2A at 55%. Understand, the engines have nothing to do with the mission capable rates of any of these aircraft. The low rates for the B‑1B and B‑2A are not engine related, nor is the high rate for the B‑52. The point is, the B‑52 is already the most reliable bomber the USAF has in its inventory. The limiting factor for all the bombers is electrical and avionics related. There is a case to be made for increasing the reliability of all the bombers, but engines will not increase or decrease that reliability. If there is money to be spent on reliability, that money does not need to be spent on B‑52 engines.

Still others make statements concerning the B‑52’s lifespan and how new engines could let it fly far past 2050. These claims are also false. The limiting factor on the B-52 service life has always been, and remains, the upper wing surface. The B‑52 upper wing surface was designed to give the aircraft a 35,000 hour service life. The reason the H-model B‑52 remains in service today is because it sat alert for decades and did not fly nearly as much as its predecessors. In terms of hours flown, the B‑52 is middle-aged. However, that timeline will have an end state. The current projections of B‑52s flying to 2040 are at current usage rates with current hours on its current wings. If the B‑52 flies past 2050 in bulk, it will need to resurface the wings, new engine or not.

Granted, a new engine can and will increase range and endurance but these performance increases are a by-product of engine efficiency. A program dedicated to increasing these capabilities does not make sense. Some engineering studies have stipulated that better engines could increase the unrefueled range of the B-52 by as much as 45%,[19] however B‑52 range is already the most impressive in the USAF fleet. The B-52 has many problems, however range and endurance are not among them. A program designed to fix non-existent problems does not need to exist.

For these reasons, a B‑52 re-engine program should not strive to increase performance in any way. Performance may increase in some areas, but it should not be the objective of the program. Similarly, fuel savings should not be the objective either. The only objective for a B‑52 re-engine that makes any sense is to reduce overall cost for the USAF.

Thanks for this, sounds reasonable. So any savings would be in maintenance costs then? How long could they fly the tf33s anyways, are there enough spares?

bikerthai · Fri Nov 08, 2019 5:26 pm

william wrote:
Performance may increase in some areas, but it should not be the objective of the program. Similarly, fuel savings should not be the objective either. The only objective for a B‑52 re-engine that makes any sense is to reduce overall cost for the USAF.

But if fuel savings reduce the over cost for the USAF, shouldn't it be part of the objective? And true, performance should not be the objective, but the ability to carry extra weapons because you have to carry less fuel is . . . Priceless :drunk:

bt

Buckeyetech · Fri Nov 08, 2019 7:18 pm

Personally, I have a hard time believing they could do all these upgrades to the entire fleet in a reasonable amount of time. By the time they would, I feel like they would only be able to fly them another decade or so.

mmo · Sat Nov 09, 2019 8:05 am

william wrote:
I The B‑52 upper wing surface was designed to give the aircraft a 35,000 hour service life. The reason the H-model B‑52 remains in service today is because it sat alert for decades and did not fly nearly as much as its predecessors. In terms of hours flown, the B‑52 is middle-aged. However, that timeline will have an end state. The current projections of B‑52s flying to 2040 are at current usage rates with current hours on its current wings. If the B‑52 flies past 2050 in bulk, it will need to resurface the wings, new engine or not.

For these reasons, a B‑52 re-engine program should not strive to increase performance in any way. Performance may increase in some areas, but it should not be the objective of the program. Similarly, fuel savings should not be the objective either. The only objective for a B‑52 re-engine that makes any sense is to reduce overall cost for the USAF.[/i]

Just a correction and comment.

Your 2040 date for the upper wing structure and skin is incorrect. It is actually 2030, and that was based on a lower annual usage than the aircraft is currently being used. https://www.nap.edu/read/5917/chapter/6#94

There are two factors driving the re-engine program. First, PW has ceased to provide support for the existing engines because of the USAF's unwillingness to commit for support or pay for support. The issue had always been there was a sufficient inventory of TF-33 engines to allow the aircraft to use the stock up and have plenty of engines left when the aircraft was finally retired. Well, that hasn't worked out for various reasons. Engine issues took a large toll on the "excess engine stock" and the decision was made to keep the aircraft around a lot longer than planned. The other issue which comes with the decision to keep the aircraft in service longer than originally planned is the increasing power requirements needed to accommodate the upgrades to ECM/Radar-Nav system and cockpit upgrades. Also, the pneumatic system/and environmental system needs upgrading. There are only 4 generators on the Buff and with the current power requirements with a generator out pt the demand right on the edge of supply. The additional upgrades would outstrip the supply of the 4 gen configuration.

Tanker dependence was also a factor in the decision but merely as a cost and the re-engine program would reduce over operating cost of the Buff.

There are major issues with any re-engine program, for example, the insertion of FADEC/EEC control and the associated wiring, the pylon change and the cockpit change for engine instruments alone are gigantic. The only engine which avoids those problems is the PW upgrade to the TF33, which, I think is DOA. Mainly because it is fairly expensive and really doesn't provide much in terms of maintenance savings. If the decision to re-engine the BUFF is approved and funded the upper wing skin will have to be dealt with. Then the BUFF could be flown way beyond 2050. Since the "airborne arsenal" aircraft is back in the discussion, there may be additional missions for the BUFF to fill.

JayinKitsap · Sat Nov 09, 2019 9:22 pm

I personally feel the CF34-10 is a good choice, not state of the art but current. Lots of them in service so parts will be available 20 years from now. I think it is right to do the radar, upgrade the cockpit like the KC-46, added power, fix the upper wing skins, etc. A full upgrade, not a half way one as so often happens.

We keep limping the B-52 along, which is not good. The decision to pull any existing buffs from the desert can be decided at the tail end of the upgrade. I do like the digital shoot out concept for the engines, it will give us better cost / benefit answers and save years.

mmo · Sat Nov 09, 2019 10:15 pm

JayinKitsap wrote:

We keep limping the B-52 along, which is not good. The decision to pull any existing buffs from the desert can be decided at the tail end of the upgrade. I do like the digital shoot out concept for the engines, it will give us better cost / benefit answers and save years.

Of course, you do realize there are only 7, IIRC, H models left in DM which would be available to be brought out of storage. I think, the plan is to do all the airframes which are available.

kc135topboom · Sun Nov 10, 2019 11:38 pm

If the upper wing reskin is not done, it makes no sense to do any other upgrades, including new engines.

Everything is just a study now. There is no funding, no design work, no production of long-lead items. Nothing just talk by the USAF.

They are running out of time for a decision of what upgrades they want, then to get the funding, design the upgrades, production of long-lead items (engines, pylons, generators, etc.), build and flight test a prototype, then schedule production of the upgrades onto the airplanes, working this all into the depot level maintenance schedule, then aircrew and maintenance training, and finally IOC.

That process will take at least 10 years, and they have yet to make a decision.

If the 2030 date for the reskin limit is good, they need to start TODAY. We are already nearly complete for FY-20Q1. With the impeachment fiasco going on in the House, they are not going to discuss B-52 funding anytime soon. With Congress beginning an election year in 2020, funding for the B-52 may already be dead.

I don't see Congress wanting to fund one upgrade at a time, reskin, then engines, then electrical, then avionics. Congress will want to fund as much as they can in one shot. They will also want to begin real funding for the B-21.

Throw in an unforeseen structural problem and the B-52 may be retiring earlier than any one of us see today.

JayinKitsap · Mon Nov 11, 2019 2:05 am

kc135-
Quite true. Look how long the A-10 rework took to the decision - far too long. Also, there are a lot of good programs clamoring to get the needed funding.

flyingclrs727 · Mon Nov 11, 2019 11:37 pm

kc135topboom wrote:
If the upper wing reskin is not done, it makes no sense to do any other upgrades, including new engines.

Everything is just a study now. There is no funding, no design work, no production of long-lead items. Nothing just talk by the USAF.

They are running out of time for a decision of what upgrades they want, then to get the funding, design the upgrades, production of long-lead items (engines, pylons, generators, etc.), build and flight test a prototype, then schedule production of the upgrades onto the airplanes, working this all into the depot level maintenance schedule, then aircrew and maintenance training, and finally IOC.

That process will take at least 10 years, and they have yet to make a decision.

If the 2030 date for the reskin limit is good, they need to start TODAY. We are already nearly complete for FY-20Q1. With the impeachment fiasco going on in the House, they are not going to discuss B-52 funding anytime soon. With Congress beginning an election year in 2020, funding for the B-52 may already be dead.

I don't see Congress wanting to fund one upgrade at a time, reskin, then engines, then electrical, then avionics. Congress will want to fund as much as they can in one shot. They will also want to begin real funding for the B-21.

Throw in an unforeseen structural problem and the B-52 may be retiring earlier than any one of us see today.

It makes sense to do the upper wing reskin at the same time as the reengine. It would make much of the structure more easily available to make the reengining modifications.

Ozair · Thu Feb 27, 2020 7:59 pm

Not really much new info in this update on the B-52 re-engine program. The vendors are obviously keen to win the work but appear to be making signals that the work will indeed be difficult given the age of the aircraft.

US Air Force faces integration challenges with B-52H re-engining

The US Air Force (USAF) faces a variety of integration issues ranging from connectivity to weight when it eventually attempts to install new engines on its fleet of Boeing B-52H Stratofortress heavy bombers.

The USAF is proceeding with this effort that is formally known as the B-52 Commercial Engine Replacement Program (CERP). CERP promises to be a big procurement opportunity for industry, as the USAF has 76 B-52Hs in service: 58 (four test) in the active service plus 18 in the Air Force Reserves. The USAF would procure at least 608 engines, as there are eight Pratt & Whitney TF33-P-3/103 turbofan engines on each platform.

The current industry offerings for CERP are Pratt & Whitney, with its PW800, and Rolls-Royce, with its VR725 from the company's family of F130 engines. General Electric (GE) is offering its legacy CF34-10 engine and its newer Passport propulsion system.

Replacing engines on an aircraft such as the B-52H, which initially entered service in the 1950s, is not as easy as simply procuring and installing new propulsion systems, even if they are commercial off-the-shelf (COTS) offerings. Christopher Johnson, Pratt & Whitney executive director for mobility and diverse engine programmes, told Jane's on 25 February that integrating new engines was risky as there were weight concerns. The USAF, he said, must ensure that the B-52H wings could handle a heaver engine if the proposed engine was indeed heavier than the TF33.

There could also be potential changes needed to physically and electronically connect the new engines in the aircraft's nacelles. Craig McVay, Rolls-Royce senior vice-president for strategic campaigns, told Jane's on 21 February that it would be very important to ensure that the B-52H, with its new engines, still received the same signals as it would with a TF33.

...

https://www.janes.com/article/94558/afa ... e-engining

mmo · Thu Feb 27, 2020 9:45 pm

Not quite sure what is meant by "same signals" but my understanding of the CREP would also include a new digital engine display, so the signal aspect would become a moot point. Also, there would be a move to replace as many "steam gauge" instruments with "glass" instruments. There are also plans to increase the generators from 4 to 6 or even 8 depending on the future power requirements.

If all the changes are implemented supposedly the H will be redesignated the J because of the substantial changes.

Ozair · Thu Feb 27, 2020 9:56 pm

mmo wrote:
Not quite sure what is meant by "same signals" but my understanding of the CREP would also include a new digital engine display, so the signal aspect would become a moot point. Also, there would be a move to replace as many "steam gauge" instruments with "glass" instruments. There are also plans to increase the generators from 4 to 6 or even 8 depending on the future power requirements.

If all the changes are implemented supposedly the H will be redesignated the J because of the substantial changes.

I wonder if it is a sign of the different integration options that the engine vendors are proposing, perhaps RR is suggesting a change with engine but minimal else to save the USAF money?

Who is online

Popular Searches On Airliners.net