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cmb56
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B-52 Re-engine Proposal Botched

Tue Oct 28, 2014 11:18 pm

Aviation week has an article out concerning how proposals going back many years into the 1980 to re-engine the B-52 were botched.
Big surprise there another government/military project that actually made economic sense is hoses up once again. Perhaps the old BUFF would look good with 4 PW geared turbo fans under the wings.
Fly half way round the world on one fill up.
 
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teme82
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RE: B-52 Re-engine Proposal Botched

Wed Oct 29, 2014 12:03 am

Quoting cmb56 (Thread starter):
Fly half way round the world on one fill up.

Or loiter on operational area ready to drop a deadly load of ammunition.
 
redflyer
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RE: B-52 Re-engine Proposal Botched

Wed Oct 29, 2014 12:09 am

Quoting cmb56 (Thread starter):
Aviation week has an article out concerning how proposals going back many years into the 1980 to re-engine the B-52 were botched.

I didn't grasp what you were saying in your post until I looked up the article.

http://aviationweek.com/defense/opin...bling-caused-b-52-reengining-delay

It makes a lot more sense now as to why this program never panned out. I could never understand why the USAF never moved earlier to re-engine the B-52s. This article, although an opinion piece, lays out the mis-steps along the way. Maybe this program will finally come to fruition. One can only hope...
 
30989
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RE: B-52 Re-engine Proposal Botched

Wed Oct 29, 2014 8:50 am

Quoting redflyer (Reply 2):

Interesting article. In Germany, NATOs Awacs are also very unpopular by local population because of their un-hushkitted engines. The population does not oppose Nato, but wants re-engining.

Personally, I can fully understand this, even though I love the "sound of freedom" those old engines produce. Still, would re-engining of the B-52 still make sense today? Those planes are almost 60 years old by now.
 
mmo
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RE: B-52 Re-engine Proposal Botched

Wed Oct 29, 2014 10:19 am

Quoting TheSonntag (Reply 3):
Still, would re-engining of the B-52 still make sense today? Those planes are almost 60 years old by now.

Given the plan is to keep the BUFF in active service until the 2040s, it makes a lot of sense! The biggest issue is the increasing maintenance on the engines and the cost of fuel delivered via a tanker. There is a very quick payback on the investment if you use the correct cost assumptions.
 
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seahawk
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RE: B-52 Re-engine Proposal Botched

Wed Oct 29, 2014 11:44 am

The biggest issue is the very bad rudder control of the BUFF. So engine out situation could be a problem with asymetric thrust. In fact if one of the otuer engines fails, the 2 inner alone would be need to be able to fly the Buff, as the thrust of the outer one working would need to be reduced by quite a lot.
 
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scbriml
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RE: B-52 Re-engine Proposal Botched

Wed Oct 29, 2014 11:55 am

Quoting seahawk (Reply 5):
So engine out situation could be a problem with asymetric thrust. In fact if one of the otuer engines fails, the 2 inner alone would be need to be able to fly the Buff, as the thrust of the outer one working would need to be reduced by quite a lot.

Ah, the dreaded six and a half engine approach.   
 
dw747400
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RE: B-52 Re-engine Proposal Botched

Wed Oct 29, 2014 4:14 pm

Quoting seahawk (Reply 5):
The biggest issue is the very bad rudder control of the BUFF.

Given that current procedures call for shutting down the entire pod in the event of an engine fire, it seems possible to operate the aircraft on six without too much trouble. Of course, an outboard failure at a critical point during takeoff might be a bigger issue... but the higher thrust available from the engines might even allow the outboards to be derated enough to keep everything within limits.
 
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zeke
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RE: B-52 Re-engine Proposal Botched

Wed Oct 29, 2014 4:26 pm

I have advocated on the other thread about using the new gen A320 engines on b52, and was shot down.
 
mmo
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RE: B-52 Re-engine Proposal Botched

Wed Oct 29, 2014 6:49 pm

Trust me, it's not an issue at all!!!
 
sovietjet
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RE: B-52 Re-engine Proposal Botched

Wed Oct 29, 2014 8:05 pm

As an aviation fan, I hope the B-52 never gets re-engined. Why put a boring high bypass turbofan on that classic??

From an economic standpoint, yes it would burn less fuel but fuel efficiency is hardly the biggest concern for the military. The B-52 fleet is such a small fraction of the USAF, the decreased fuel burn would hardly be noticeable. However, re-engining them would be a large lump sum which will definitely be noticeable.
 
ThePointblank
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RE: B-52 Re-engine Proposal Botched

Thu Oct 30, 2014 4:44 am

Quoting sovietjet (Reply 10):
From an economic standpoint, yes it would burn less fuel but fuel efficiency is hardly the biggest concern for the military. The B-52 fleet is such a small fraction of the USAF, the decreased fuel burn would hardly be noticeable. However, re-engining them would be a large lump sum which will definitely be noticeable.

The maintenance on the B-52's engines is already extremely expensive. Maintenance costs for the TF33 is outrageous and will continue to go up as they age. New engines will last at least four times as long between overhauls and be cheaper to maintain due to commercial engine equivalents in active use.

Reengining the B-52 proposals isn't new, and proposals have been kicking around for a while. Take this one:

http://fas.org/nuke/guide/usa/bomber/b-52.htm

Quote:
An unsolicited proposal for reengining 94 aircraft in the B-52 fleet was submitted to the Air Force by Boeing North American, Inc. in June 1996. Boeing proposed modernizing the B-52 fleet by replacing the current TF-33 engines with a commercial engine through a long-term leasing agreement, and providing fixed-cost, privatized maintenance based on the number of hours flown each year. Boeing's proposal included modernizing the B-52 fleet by replacing the TF-33 engines with the Allison/Rolls commercial RB-211 engine through a long-term leasing agreement and providing a fixed-cost, privatized maintenance concept through a "power-by-the-hour" arrangement. Boeing initially projected reengining cost savings of about $6 billion, but later revised the projected savings to $4.7 billion to reengine 71 B-52s. An Air Force team formed to study Boeing's proposal analyzed the lease and purchase alternatives and concluded that both options are cost prohibitive compared to maintaining the existing TF-33 engines. The General Accounting Office estimated that Boeing's unsolicited proposal to reengine the B-52 fleet would cost the Air Force approximately $1.3 billion rather than save approximately $4.7 billion as Boeing projected.

Note the assumption made by the GAO regarding the price of fuel. How much was fuel in 1996 versus 2014? The biggest flaw in the GAO's numbers was that "The value of fuel savings would accrue at a constant 87 cents per gallon (the Defense Energy Support Center standard price at the time) over the remaining 40 year airframe life." Fuel today is WAY more expensive now; the current contracts are at around $2-2.5 per gallon per the DLA. Considering how long they now want to fly the B-52's, this would have saved money!
 
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seahawk
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RE: B-52 Re-engine Proposal Botched

Thu Oct 30, 2014 8:34 am

Quoting dw747400 (Reply 7):
Given that current procedures call for shutting down the entire pod in the event of an engine fire, it seems possible to operate the aircraft on six without too much trouble. Of course, an outboard failure at a critical point during takeoff might be a bigger issue... but the higher thrust available from the engines might even allow the outboards to be derated enough to keep everything within limits.

Yes it is possible, you just need to reserve thrust for the failure of an outer engine.

http://books.google.de/books?id=8UL7...&q=B-52%20engine%20failure&f=false
 
mmo
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RE: B-52 Re-engine Proposal Botched

Thu Oct 30, 2014 9:34 am

Quoting dw747400 (Reply 7):
Given that current procedures call for shutting down the entire pod in the event of an engine fire,

Just out of curiosity, where did this come from?????
 
30989
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RE: B-52 Re-engine Proposal Botched

Thu Oct 30, 2014 9:58 am

Quoting sovietjet (Reply 10):
As an aviation fan, I hope the B-52 never gets re-engined. Why put a boring high bypass turbofan on that classic??

I agree. Same applies to the Awacs. But I do not live near the airport.
 
cmb56
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RE: B-52 Re-engine Proposal Botched

Fri Oct 31, 2014 9:34 am

The solution is relatively simple.
Lease the engines and pay by the hour.
The AF would have to pay for the new pylons and installation etc but you have a fixed per hour cost for the engines with a massive reduction in fuel burn.
Since the new engines would be FADEC automatic changes in thrust to offset what would likely be an extremely rare event, engine loss on takeoff, should be easy.
Stick with something commercial off the shelf like the same engine current standard on the 737 or A320.
 
dw747400
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RE: B-52 Re-engine Proposal Botched

Sat Nov 01, 2014 2:35 am

Quoting mmo (Reply 13):
Just out of curiosity, where did this come from?????

I have several friends that fly the B-52, one of whom described a recent engine fire to me.
 
mmo
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RE: B-52 Re-engine Proposal Botched

Sat Nov 01, 2014 6:42 am

Quoting dw747400 (Reply 16):
I have several friends that fly the B-52, one of whom described a recent engine fire to me.

Interesting, because the current -1 just calls for the engine to be shut down. If the fire will not extinguish then the other engine is shut down. For a simple engine failure just the applicable engine is secured. The BUFF has plenty of rudder authority for a go around with 4 out on one side. One figure that is computed it VMCA and as long as you stay above that, which is done by a no flap approach, you will have plenty of control authority. However, my guess is with new engines you will have to have a mod to increase the rudder authority.
 
Max Q
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RE: B-52 Re-engine Proposal Botched

Sat Nov 01, 2014 10:22 am

Quoting mmo (Reply 17):
However, my guess is with new engines you will have to have a mod to increase the rudder authority.

Perhaps, but that's not the whole story, you have to consider the overall stress on the airframe.
 
mmo
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RE: B-52 Re-engine Proposal Botched

Sat Nov 01, 2014 11:41 am

Quoting Max Q (Reply 18):
Perhaps, but that's not the whole story, you have to consider the overall stress on the airframe.

No one said that was the only mod. The entire electrical, pneumatic and hydraulic systems will have to be redesigned. The airframe is not the issue. The limiting factor is the upper wing skin.
 
747400sp
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RE: B-52 Re-engine Proposal Botched

Sat Nov 08, 2014 7:05 pm

I think they should look into putting six CFM 56 2, 5 or if they want something more modern, the dash 7.
 
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ptrjong
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RE: B-52 Re-engine Proposal Botched

Sat Nov 08, 2014 7:18 pm

Quoting 747400sp (Reply 20):

Four is plenty for a 220 tonnes aircraft.
 
747400sp
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RE: B-52 Re-engine Proposal Botched

Sun Nov 09, 2014 2:20 am

Quoting ptrjong (Reply 21):
Four is plenty for a 220 tonnes aircraft.

Well if they do go with four engines, I hope it is P&W Pure 1000G, because four CFM 56s has been done by KC-135s, DC-8s and 707s, four PW 2000 has been gone by the C-17, it time for some thing new.


I read that the 80s re-engine proposal, was to have B-52s re-engined with six CFM 56-2s.
 
ThePointblank
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RE: B-52 Re-engine Proposal Botched

Sun Nov 09, 2014 4:08 am

Quoting 747400sp (Reply 22):

I read that the 80s re-engine proposal, was to have B-52s re-engined with six CFM 56-2s.

Replacing the current configuration with high-bypass turbofans was proposed as early as the 1960s, when such powerplants first entered development (THAT would have been the time to do it).

Long story short, the idea kept getting dropped because no one ever expected the B-52's to be around too much longer. There was always some sort of development program that was supposed to replace the B-52, but never did (often fell to the budget axe). Even now, there's some debate as to whether the remaining ~78 aircraft will be in service long enough to make the upgrade worthwhile. With the KC-135E's going offline, there will be a time when the TF-33 engines can no longer be supported, and I believe that would force the issue more than anything.
 
Max Q
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RE: B-52 Re-engine Proposal Botched

Sun Nov 09, 2014 10:55 am

It is an amazing aircraft, does anyone know if there are ANY plans to replace it, or will they just keep rebuilding it
indefinitely ?
 
mmo
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RE: B-52 Re-engine Proposal Botched

Sun Nov 09, 2014 11:47 am

Quoting ThePointblank (Reply 23):
Long story short, the idea kept getting dropped because no one ever expected the B-52's to be around too much longer

That is partially correct. The biggest reason for the lack of interest was the assumptions used did not have an economic payback in a reasonable length of time. Specifically, the cost of overhaul on the TF-33 and the cost of inflight refueling.

The TF-33 maintenance has risen by 300% over what the assumptions were in all the studies. The cost of fuel/gallon from inflight refueling was grossly underestimated. There was no cost increase for fuel received from tankers. In reality, the cost/gallon for tanker fuel is around $15/gallon. Had the correct numbers been used, the payback criteria would have been met. As it is now, even if there are only 10 years left of active service for the BUFF, there is still an economic case to re-engine the fleet.

Quoting Max Q (Reply 24):
It is an amazing aircraft, does anyone know if there are ANY plans to replace it, or will they just keep rebuilding it
indefinitely ?

The only thing on the horizon is the LRS-B (Long Range Strike Bomber) which is underdevelopment to replace the current range of bombers. Initial IOC is expected in the mid 2020's.
 
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ptrjong
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RE: B-52 Re-engine Proposal Botched

Sun Nov 09, 2014 9:36 pm

Quoting 747400sp (Reply 22):
I read that the 80s re-engine proposal, was to have B-52s re-engined with six CFM 56-2s.

I didn't know that, but a six-engine upgrade must be a lot more complicated than a four-engine one?

Also CMF56 thrust has gone up from less than 100 kN to 120 kN in the 737-800/900, whether you like it or not.
 
Max Q
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RE: B-52 Re-engine Proposal Botched

Mon Nov 10, 2014 5:37 am

Quoting mmo (Reply 25):
The only thing on the horizon is the LRS-B (Long Range Strike Bomber) which is underdevelopment to replace the current range of bombers. Initial IOC is expected in the mid 2020's.

I wonder if that will replace the B52 though,


Problem is it could well end up being like the B2 which ended up being so expensive the planned production was cut from
130 down to 20 !


Besides the B52 doesnt really do the kind of missions that the B2 and future LRS-B are planned to do, stealth isn't a requirement.


If they could build enough numbers of the future bomber maybe the B1 could finally replace the B52 (as it was originally intended ! )
 
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kc135topboom
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RE: B-52 Re-engine Proposal Botched

Sun Nov 16, 2014 5:23 pm

The bottom line is the USAF really doesn't have to reengine the B-52H. They have thousands of spare TF-33 and J-57 engines to be used for parts.

No, they cannot put a J-57 from a KC-135A or B-52F/G onto a B-52H, but the J-57 (P&W JT-3C) is the non-fan version of the TF-33 (P&W JT-3D) and many parts (not all) are interchangeable.

The TF-33 engines come from mostly KC-135Es and various RC-135 models. They would all have to be derated to the TF-33-P3/-P103 configuration. The engines that came off of the C-135 series were all TF-33-P5/-P7/-P9/ or -P100 engines.
 
mmo
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RE: B-52 Re-engine Proposal Botched

Sun Nov 16, 2014 7:06 pm

Quoting KC135TopBoom (Reply 28):
The bottom line is the USAF really doesn't have to reengine the B-52H. They have thousands of spare TF-33 and J-57 engines to be used for parts.

That's just the thing, they really don't. In addition the depot costs for TF-33 overhaul has increased by over 300%. There are issues with vendors no longer being in business to replace parts needed for the engines. So, in reality, the TF-33 is probably on it's last legs with the B-52 fleet.
 
30989
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RE: B-52 Re-engine Proposal Botched

Sun Nov 16, 2014 9:37 pm

Maybe the question is naive, but is it impossible with modern tooling to produce new TF-33 spare parts, if needed?
 
ThePointblank
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RE: B-52 Re-engine Proposal Botched

Mon Nov 17, 2014 2:16 am

Quoting TheSonntag (Reply 30):
Maybe the question is naive, but is it impossible with modern tooling to produce new TF-33 spare parts, if needed?

Anything can happen if you have the money, but it isn't going to be very cost effective. We are talking about limited production runs, which will drive up costs immensely.

Quoting mmo (Reply 29):

That's just the thing, they really don't. In addition the depot costs for TF-33 overhaul has increased by over 300%. There are issues with vendors no longer being in business to replace parts needed for the engines. So, in reality, the TF-33 is probably on it's last legs with the B-52 fleet.

  

Yup. In FY 2006, engine overhaul costs for a TF-33 engine was $1.25 million per engine, up 300% from FY 1996, which was $257,000 per engine. The main reason? OEM no longer supporting the engine in commercial applications because commercial users had already retired aircraft using the same engine due to noise regulations and fuel economy.

Parts obsolesce, plus costs of overhauls have shot up dramatically in the last few years. When OEM's no longer support the product, that is trouble for any user, even an important user like the USAF.

Also note that the USAF has devoted a lot of resources to maintain the TF-33 and related engines. As long as there is a significant number of TF-33 engines in USAF service, the USAF must maintain the level of resources needed. Last numbers I heard was that $800,000 dollars a year, plus 188 personnel and 82,000 square feet of workshop space is devoted to TF-33 engine overhauls. With the KC-135E fleet out, the E-8's and RC-135's getting new engines or have new engines, that just leaves the B-52's with the TF-33 engine.
 
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seahawk
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RE: B-52 Re-engine Proposal Botched

Mon Nov 17, 2014 12:25 pm

E-3s also use the TF-33.
 
sovietjet
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RE: B-52 Re-engine Proposal Botched

Mon Nov 17, 2014 5:39 pm

E-8s, E-3s, OC-135s and B-52s use the TF-33. I'm pretty sure they indeed do have a lot of TF-33s in storage. The cost to overhaul has gone up but there should still be plenty of parts. Don't forget all those civil 707s in the desert also got harvested for parts.
 
mmo
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RE: B-52 Re-engine Proposal Botched

Mon Nov 17, 2014 8:47 pm

Quoting sovietjet (Reply 33):
The cost to overhaul has gone up but there should still be plenty of parts.

So, I guess all the recent studies of the costs have the costs just fabricated??? There may be plenty of TF-33s but it would appear they are all worthless.

In addition, it's not only the cost of maintaining the engines that was flawed, but the cost of fuel during air refueling was incorrectly priced. Both studies used the cost of fuel the USAF paid in the ground. No adjustment was made for the cost of the actual air refueling. One recent study had the cost of fuel from a tanker at $15.00/gallon. So, it's not just one issue but many issues that are not correct.

[Edited 2014-11-17 12:51:04]
 
ThePointblank
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RE: B-52 Re-engine Proposal Botched

Tue Nov 18, 2014 1:55 am

Quoting sovietjet (Reply 33):
E-8s,

E-8 is getting a new engine; the Pratt JT8D.

Quoting sovietjet (Reply 33):
E-3s

Proposals exist to re-engine the type with serious consideration being given. The lead candidate is the Pratt JT8D from the E-8 program, and NATO is already planning such an upgrade.

It should be noted, as a side note that French, British and Saudi E-3's are actually more capable than USAF and NATO E-3's. Reason why? French, British and Saudi E-3's are all powered by CFM-56 engines, which allows for higher cruise altitudes, and longer endurance.

Quoting sovietjet (Reply 33):
OC-135s

They don't fly often, but it is more likely that they will either be replaced or re-engined.

Quoting sovietjet (Reply 33):
The cost to overhaul has gone up but there should still be plenty of parts

At 3x the cost as it used to, and it has probably gone up even more since the last study.

Quoting sovietjet (Reply 33):
Don't forget all those civil 707s in the desert also got harvested for parts.

They've already been harvested for parts. In fact, KC-135E's, which have the engines harvested from old 707's, are now all retired.
 
prebennorholm
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RE: B-52 Re-engine Proposal Botched

Tue Nov 18, 2014 3:03 am

Quoting mmo (Reply 34):
One recent study had the cost of fuel from a tanker at $15.00/gallon. So, it's not just one issue but many issues that are not correct.

Of course aerial refueling is immensely expensive. But how relevant is this study?

The vast majority of B-52 refueling hookups are dry training hookups. Whatever engine on the B-52, the crews need to train refueling equally much.

And when they are hooked up, then there is no serious extra cost if they also let a few gallons flow.

It was another thing if they day in and day out were used to deliver bombs half way around the globe.

Hopefully they will, until retirement in 2040 or so, only be used for training flights.
 
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seahawk
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RE: B-52 Re-engine Proposal Botched

Tue Nov 18, 2014 6:59 am

And parts expire over time.

JT8D-219 is the obvious TF33 replacement.
 
mmo
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RE: B-52 Re-engine Proposal Botched

Tue Nov 18, 2014 7:10 am

Quoting prebennorholm (Reply 36):
Of course aerial refueling is immensely expensive. But how relevant is this study?

The vast majority of B-52 refueling hookups are dry training hookups. Whatever engine on the B-52, the crews need to train refueling equally much.

As a minimum, from my own past experience, 10,000 lbs are transferred. If you look at the worldwide operations now in effect, your statement that "most refueling hookups are training hookups" is not quite correct. When I flew them, we usually took on 60,000 lbs on each mission. There were several times where we took on 120,0000 from 2 tankers and there were even more times where we had multiple refueling during the flight.

As far as relevance of the studies, it is extremely relevant since the re-engining proposals all have the range increase by at least 30%, thus reducing the demand on the tanker support. Thus there is even more of an economic payback using the relevant cost figures.

Quoting prebennorholm (Reply 36):
Hopefully they will, until retirement in 2040 or so, only be used for training flights

Have you been reading the news lately? I don't think that's going to happen anytime soon.
 
na
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RE: B-52 Re-engine Proposal Botched

Tue Nov 18, 2014 1:31 pm

I have always thought that the reason why the B-52 was never re-engined was that it for most of the time it was planned to retire them earlier, mainly by the B-1 and B-2 which in the event both proved to be much too expensive. But if they really want to keep the B-52H fleet operational until 2040 they should hurry up now.

Btw, I never understood why the B-52 was called BUFF - Big Ugly Fat Fellow. Its neither ugly nor fat, even the opposite is the case. Its the best looking bomber ever, and its slim.

I recently read that the defense ministry has kicked off a program for a new strategic bomber. Any details about that?
 
cargotanker
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RE: B-52 Re-engine Proposal Botched

Tue Nov 18, 2014 11:33 pm

Quoting mmo (Reply 38):
As a minimum, from my own past experience, 10,000 lbs are transferred. If you look at the worldwide operations now in effect, your statement that "most refueling hookups are training hookups" is not quite correct. When I flew them, we usually took on 60,000 lbs on each mission. There were several times where we took on 120,0000 from 2 tankers and there were even more times where we had multiple refueling during the flight.

The overwhelming majority of training missions I performed with B-52s, B-1s, and B-2s included ZERO fuel offload, just enough to keep the boom wet. I think that the majority of B-52 refueling hookups are training missions now, though that may not have been the case at the peak of OIF/OEF.


Quoting mmo (Reply 34):
No adjustment was made for the cost of the actual air refueling. One recent study had the cost of fuel from a tanker at $15.00/gallon. So, it's not just one issue but many issues that are not correct.

I can't see this being a significant factor. What percent of fuel currently used by the B-52 fleet originally comes from tankers? 10%?
 
prebennorholm
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RE: B-52 Re-engine Proposal Botched

Wed Nov 19, 2014 4:16 am

Quoting cargotanker (Reply 40):
I think that the majority of B-52 refueling hookups are training missions now, though that may not have been the case at the peak of OIF/OEF.

I can't imagine one single non-training B-52 flight since OIF/OEF, which is somewhat over ten years ago. Did I miss something?

Quoting cargotanker (Reply 40):
I can't see this being a significant factor. What percent of fuel currently used by the B-52 fleet originally comes from tankers? 10%?

Right. But even if its may be 20 or 30% instead of 10%, so what?

You need so and so many training hookups. Two planes are needed for a series of training hookups. Whether both planes take off with fuel for the mission making only dry hookups, or some fuel is delivered, it doesn't change the overall cost of that training mission.

Only when the B-52 has to perform a mission, for which refueling is needed to fulfill the mission, does it change the cost. Because then fewer tankers are needed in the air.
 
cargotanker
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RE: B-52 Re-engine Proposal Botched

Wed Nov 19, 2014 4:52 pm

Quoting prebennorholm (Reply 41):
I can't imagine one single non-training B-52 flight since OIF/OEF, which is somewhat over ten years ago. Did I miss something?

Combat (operational) missions are different from training missions. B-52s have been deployed to SWA multiple times since OEF started. Deployments to Guam to counter North Korea/China also count as operational.

Quoting prebennorholm (Reply 41):
Right. But even if its may be 20 or 30% instead of 10%, so what?

So....you agree with me?
 
mmo
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RE: B-52 Re-engine Proposal Botched

Wed Nov 19, 2014 5:03 pm

Quoting cargotanker (Reply 40):
I think that the majority of B-52 refueling hookups are training missions now, though that may not have been the case at the peak of OIF/OEF.

After speaking to a friend of mine who still flies the Stratopig in the AF Reserves, he stated he couldn't remember a time where he had a token offload from a tanker. He stated most of the training sorties he's flown, and there are not that many, have had an offload of around 25-30,000 lbs. Typically the offload was close to the end of the flight and then there was an engine running crew change for pattern work.
 
prebennorholm
Posts: 7295
Joined: Tue Mar 21, 2000 6:25 am

RE: B-52 Re-engine Proposal Botched

Thu Nov 20, 2014 3:40 am

Quoting cargotanker (Reply 42):
So....you agree with me?

Yes, I do.

Quoting cargotanker (Reply 42):
Combat (operational) missions are different from training missions. B-52s have been deployed to SWA multiple times since OEF started. Deployments to Guam to counter North Korea/China also count as operational.

Okay, deployment to Guam isn't pure training flight. But then it easily goes to Guam without refueling. Maybe they do (sometimes) refuel on such flights, but then it counts as a training refueling.

When at Guam, then it sits there telling certain people in North Korea etc: "Don't do anything stupid".

Sure the B-52 could become a more range and fuel efficient plane with more modern engines, but I am very sceptical about some of the economic calculations, which has been given on this thread.

First of all, nobody would remove the refueling capability, if reengined. Therefore the huge extra cost of refueling should be applied to refueling training. Until WWIII break out, which God forbid ever happens.

Some posters indicate that maintenance of the TF33 has risen several hundred percent over a few years. If correct, then there must be some reason for that.

Could it be that the Air Force orders certain spares one by one at P&W? And P&W then produces those spares one by one?

The alternative could be: "We have decided to keep the B-52 flying with TF33 for at least X hours over Y years. Please, dear P&W, make a contract with us for spares for X hours and Y years".

Of course I have no idea if it is that simple. But it isn't like wages of mechanics have risen those hundreds of percent in a few years, so there must be a reason, which can be identified and corrected.

The reason is certainly not that it is an experimental engine for which future maintenance is unpredictable.

Even if it is correct that a TF33 overhaul shall cost well into the seven-digets, then what real money is that? How often is each engine in for an overhaul? Every 10, 15 or 20 years? These engines are not running 12 hours each day like when they were mounted on PanAm 707s.

I assume that the B-52 of today is considered an "ALCM truck". And that it does that job pretty well, while mostly sitting in the hangar waiting for ALCMs to be trucked, which hopefully never happens.

Reengining them is a huge up front cost. Would all that money be better spent on fifty new and modern ALCM trucks? Modified Boeing 767s? Like the 737 (P-8) replaces the P-3.

I don't think that decision is in any hurry.

[Edited 2014-11-19 19:46:32]
 
ThePointblank
Posts: 4426
Joined: Sat Jan 17, 2009 11:39 pm

RE: B-52 Re-engine Proposal Botched

Thu Nov 20, 2014 6:24 am

Quoting prebennorholm (Reply 44):
I assume that the B-52 of today is considered an "ALCM truck". And that it does that job pretty well, while mostly sitting in the hangar waiting for ALCMs to be trucked, which hopefully never happens.

ALCM is expected to expire in the USAF's inventory by 2020. That would leave the B-52 without a nuclear mission capability.
 
mmo
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Joined: Thu Apr 18, 2013 3:04 pm

RE: B-52 Re-engine Proposal Botched

Thu Nov 20, 2014 7:18 am

Quoting prebennorholm (Reply 44):
Some posters indicate that maintenance of the TF33 has risen several hundred percent over a few years. If correct, then there must be some reason for that.

As has been pointed out previously, the main reason is the lack of available parts. While the TF-33 is a first generation, low bypass engine, it's commercial twin is no longer in service. All of the engines that were purchased with the 707s have been cannibalized, so the parts are driving the costs upward.

Quoting prebennorholm (Reply 44):
Okay, deployment to Guam isn't pure training flight. But then it easily goes to Guam without refueling. Maybe they do (sometimes) refuel on such flights, but then it counts as a training refueling.

Actually, it would not be a training sortie. Having flown that deployment several times, it will not make it without at least one refueling westbound. Coming back, you can do it with a small tanker offload, but westbound you need to take on fuel.

Quoting prebennorholm (Reply 44):
Even if it is correct that a TF33 overhaul shall cost well into the seven-digets, then what real money is that? How often is each engine in for an overhaul? Every 10, 15 or 20 years? These engines are not running 12 hours each day like when they were mounted on PanAm 707s.

The performance of the TF-33 is light years behind the engines used on commercial aircraft. Even comparing the TF-33 to the old JT8 is not fair. First of all, there is no ability to do on-wing component repair as there is in current generation engines. So anything other than a minor repair requires the engine be taken off the wing. The engine shops are limited in what they can do, so most repairs are accomplished at the depot level. If I remember correctly, the removal rate is higher by a factor of 10 than commercial engines.


Quoting prebennorholm (Reply 44):
I assume that the B-52 of today is considered an "ALCM truck". And that it does that job pretty well, while mostly sitting in the hangar waiting for ALCMs to be trucked, which hopefully never happens.

I don't know if I would say truck but you forget the SIOP load would also include 4 gravity bombs which would be delivered several hours after the MIRV'ed warheads are delivered. There is a program of BDA (battle damage assessment) which the BUFFs were tasked with performing. While having only 4 special weapons, they might have 8 or 10 targets to assess. So, to portray them as just delivery trucks in not quite accurate.

Quoting ThePointblank (Reply 45):
ALCM is expected to expire in the USAF's inventory by 2020. That would leave the B-52 without a nuclear mission capability.


See AGM-158 JASSM....and there is currently another stealth cruise missile in development. See LRSO.

[Edited 2014-11-19 23:20:04]
 
ThePointblank
Posts: 4426
Joined: Sat Jan 17, 2009 11:39 pm

RE: B-52 Re-engine Proposal Botched

Thu Nov 20, 2014 7:22 am

Quoting mmo (Reply 46):
See AGM-158 JASSM....and there is currently another stealth cruise missile in development.

JASSM is expected to be integrated on B-52, but it will be at least 3 more years before that comes about. The B-1 is already JASSM capable.
 
Buckeyetech
Posts: 229
Joined: Wed Jul 03, 2013 1:11 am

Re: B-52 Re-engine Proposal Botched

Tue Feb 07, 2017 10:49 pm

I thought the issue was dead, but it has popped up again.

http://www.defensenews.com/articles/us- ... ign=buffer
 
LightningZ71
Posts: 688
Joined: Sat Aug 27, 2016 10:59 pm

Re: B-52 Re-engine Proposal Botched

Wed Feb 08, 2017 5:00 am

(in response to the article)

FINALLY! someone wises up and takes a look at the BR-7XX series for the B-52 re-engine program. It is dimensionally appropriate for the existing nacelles, has similar thrust capability to the existing TF33s, is a solid commercial powerplant that is widely supported, and is quite fuel efficient.

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