Boeing B-52J / B-52 Re-Engining

[mkellytx]

Are you talking about the earlier J-57 powered models?

Yes, some of those guys flew on D's and G's back in the day and were trained by the guys who flew other earlier models.

 

[Josh_TN]

Is there any open source schedule for the B-52Js entering service? I think I read somewhere the first conversion would be 2028 or so, but I was interested in how many will be converted per year. I assume the numbers are low given that the aircraft will have to be taken out of service, creating a shortage of platforms.

Alternatively, is there a completion date suggested for the program?

 

[Orionblamblam]

 

[NMaude]

IMO if Boeing is going to be doing this massive refit then the B-52's ejection seats should be replaced with Martin-Baker seats.

 

[FighterJock]

I wonder how many years do Ejection Seats have on them before they are due to be replaced? I agree with NMaude that getting more modern Martin-Baker seats would be more beneficial to the B-52J crew than sticking with the old seats.

 

[Scott Kenny]

I wonder how many years do Ejection Seats have on them before they are due to be replaced? I agree with NMaude that getting more modern Martin-Baker seats would be more beneficial to the B-52J crew than sticking with the old seats.

Who does the seats for F-35 and B-21? M-B?

The other option would be reusing F-15 seats.

 

[aim9xray]

Don't forget the two downward ejecting seats in the basement. Or will those be removed for the new EMP-rated Espresso station? (Shades of "The Big Bus".)

 

[Josh_TN]

I suspect the seats to be removed are topside. I think TXKelly remarked on this previously. In which case changing seats could only happen for half the crew anyway (crew reduction to 4 in the J version).

 

[Scott Kenny]

Don't forget the two downward ejecting seats in the basement. Or will those be removed for the new EMP-rated Espresso station? (Shades of "The Big Bus".)

Isn't crew going to 4 upstairs?

 

[Josh_TN]

Isn't crew going to 4 upstairs?

I don’t think it has been explicitly stated, but TXKelly who has flown the type before I believe said that it would be very hard to move the stations from the forward lower deck position. I don’t want to put words in his mouth but I *think* he mentioned that in this thread, and I tend to take anything he posts at high value if that was the case.

The USAF itself I do not think has released any information on the subject.

 

[Scott Kenny]

I don’t think it has been explicitly stated, but TXKelly who has flown the type before I believe said that it would be very hard to move the stations from the forward lower deck position. I don’t want to put words in his mouth but I *think* he mentioned that in this thread, and I tend to take anything he posts at high value if that was the case.

The USAF itself I do not think has released any information on the subject.

Hrm, right. The lower deck is bombardier and navigator. Probably would be a pain to move those guys up to the main deck where the systems folks were.

They may not change out any of the seats, then.

 

[NMaude]

Who does the seats for F-35 and B-21? M-B?

I don't know who's supplying the seats for the B-21 but the F-35 uses the Martin-Baker US16E seat.

Don't forget the two downward ejecting seats in the basement.

It wouldn't be hard for MB to modify one of its' seat designs for downward ejection.

 

[aim9xray]

It wouldn't be hard for MB to modify one of its' seat designs for downward ejection.

Quite easily done, no inconvenience at all. (I could be wrong, but I think that there is more to be done than just turning the rocket motor(s) 180 degrees.) And how long to qualify it versus the B-52J schedule? (Looking at you, T-7A.)

 

[NMaude]

but I think that there is more to be done than just turning the rocket motor(s) 180 degrees.)

A downward ejection-seat for obvious reasons won't be fitted with a rocket-motor.

 

[aim9xray]

...nor will it be rated as "zero-zero".

 

[NMaude]

...nor will it be rated as "zero-zero".

There's a reason why the downward ejection-seats were referred to as "Automatic self-burial".

 

[Scott Kenny]

...nor will it be rated as "zero-zero".

Which is why I'd much rather move the radar nav and bombardier to the upper deck and give them F-35 seats.

 

[NMaude]

Which is why I'd much rather move the radar nav and bombardier to the upper deck and give them F-35 seats.

While possible I strongly suspect that moving those two crew members from the lower deck to the upper deck would be a lot easier said than done (No doubt such a rearrangement of the cockpit could be done but I suspect it would be time consuming and cost a lot of money).

 

[Foo Fighter]

Might be contrteversial but, more sense moving crew to one deck with seat replacement and all 0/0. It's worth doing so do it properly imho.

 

[FighterJock]

I agree with Foo Fighter, get all the crew up to the top deck and give them all new upward ejecting seats for added safety. Having downward ejecting seats were not safe for the crew and should be taken out.

 

[Sundog]

Moving the lower deck seats to the upper deck would amount to a massive structural rework of the nose of the aircraft for all kinds of reasons and that isn’t going to happen. Unless they reduce crew size, due to AI / automation / systems redesign such that they combine what the four crewman did into just requiring two crewman. Then I could see them eliminating the two seats in the lower deck.

 

[Anduriel]

Moving the lower deck seats to the upper deck would amount to a massive structural rework of the nose of the aircraft for all kinds of reasons and that isn’t going to happen. Unless they reduce crew size, due to AI / automation / systems redesign such that they combine what the four crewman did into just requiring two crewman. Then I could see them eliminating the two seats in the lower deck.

Question: why should you move anything?
As I understand, crew is reduced to 4, so stations on lower deck are unnecessary, and their crew tasks are taken by upper deck crew with new stations, with modern screens and whatnot. So all you have to do is just remove seats on lower deck/dismantle old stations, add some weights to balance things out (or just leave them intact), and replace seats for crews on upper deck. B-2 crew somehow is enough to operate plane that much more demanding to pilot, so why 4 people for B-52 with modern systems are not enough? Tu-160, being much less upgraded (excluding M2 verison ofc), has 4. Tu-22M3 also has 4.

 

[aim9xray]

As I understand it, it's not the aircraft structure per se. It's the wiring. For reliability, you don't cut the harness and then splice in a new extension cord going to the attic. (And despite what you hear, wire stretchers are apocryphal, along with five gallon buckets of jet wash.)

Instead, the old harnesses are stripped out of the airplane and new one are laboriously constructed on wire boards and then installed. After installation, the bundle is trimmed to fit and then pin-terminated with new connectors (Amphenol, thy name is ...). Then the whole system is hooked up to a DITMCO or equivalent tester for acceptance or repair. (Oh, I forgot the EMP test and certification cycle.)

Can you see the cost in this? It's the manual labor. (And those damn connectors that had to be put back into production.)

This sort of thing (major reconfiguration and replacement) is usually done only in a major system SLEP or system upgrade (F-4B to F-4N), or "tired wire" (declining physical reliability with advanced flight hours), or flight safety (early F-16A/B Kapton-insulated wire replacement).

Otherwise, the cost is very difficult to justify to the bean counters and congress critters.

 

[Josh_TN]

Quite easily done, no inconvenience at all. (I could be wrong, but I think that there is more to be done than just turning the rocket motor(s) 180 degrees.) And how long to qualify it versus the B-52J schedule? (Looking at you, T-7A.)

I suspect it would have to be designed from scratch and would be very expensive. And also unique to the B-52.

 

[Hanz2k]

As I understand it, it's not the aircraft structure per se. It's the wiring. For reliability, you don't cut the harness and then splice in a new extension cord going to the attic. (And despite what you hear, wire stretchers are apocryphal, along with five gallon buckets of jet wash.)

Instead, the old harnesses are stripped out of the airplane and new one are laboriously constructed on wire boards and then installed. After installation, the bundle is trimmed to fit and then pin-terminated with new connectors (Amphenol, thy name is ...). Then the whole system is hooked up to a DITMCO or equivalent tester for acceptance or repair. (Oh, I forgot the EMP test and certification cycle.)

Can you see the cost in this? It's the manual labor. (And those damn connectors that had to be put back into production.)

This sort of thing (major reconfiguration and replacement) is usually done only in a major system SLEP or system upgrade (F-4B to F-4N), or "tired wire" (declining physical reliability with advanced flight hours), or flight safety (early F-16A/B Kapton-insulated wire replacement).

Otherwise, the cost is very difficult to justify to the bean counters and congress critters.

I can imagine you could build some kind of analogue to digital router / switch board and then use fiber optics to replicate consoles to the upper deck - like a remote control panel. Still a lot of work but shouldn’t weight that much.

 

[Byeman]

I can imagine you could build some kind of analogue to digital router / switch board and then use fiber optics to replicate consoles to the upper deck - like a remote control panel. Still a lot of work but shouldn’t weight that much.

not really. What was saved in wiring has been negated by all the analog to digital and digital to analog boxes. And reliability is less.

 

[Anduriel]

This sort of thing (major reconfiguration and replacement) is usually done only in a major system SLEP or system upgrade (F-4B to F-4N), or "tired wire" (declining physical reliability with advanced flight hours), or flight safety (early F-16A/B Kapton-insulated wire replacement).

Considering that a lot of systems are being removed, new engines are installed (that have different controls compared to old ones, requiring a change in wiring), and other upgrades, might as well tackle this problem.

 

[mkellytx]

I wonder how many years do Ejection Seats have on them before they are due to be replaced? I agree with NMaude that getting more modern Martin-Baker seats would be more beneficial to the B-52J crew than sticking with the old seats.

Seats are always on an overhaul cycle, memory fades on the exact cycle. None of those catapults are original, those get replaced every so many years.

 

[mkellytx]

Don't forget the two downward ejecting seats in the basement. Or will those be removed for the new EMP-rated Espresso station? (Shades of "The Big Bus".)

The offenders will stay downstairs

 

[mkellytx]

I don’t think it has been explicitly stated, but TXKelly who has flown the type before I believe said that it would be very hard to move the stations from the forward lower deck position. I don’t want to put words in his mouth but I *think* he mentioned that in this thread, and I tend to take anything he posts at high value if that was the case.

The USAF itself I do not think has released any information on the subject.

Yes @Josh_TN, unless they want to relocate a ton of stuff the offender will stay downstairs. Even if you can get by with a 4-man crew, there's still a case to be made for maintaining 6 ejection seats for training or augmented crews. Min crew BTW is 3, you can ferry the jets with AC, CP and the RN.

 

[mkellytx]

Hrm, right. The lower deck is bombardier and navigator. Probably would be a pain to move those guys up to the main deck where the systems folks were.

They may not change out any of the seats, then.

The only systems guy up there is the EWO. The guys with radiator wings are bus drivers

 

[mkellytx]

...nor will it be rated as "zero-zero".

The downward seats are good down to 200 feet and have been successfully used that low.

 

[mkellytx]

Might be contrteversial but, more sense moving crew to one deck with seat replacement and all 0/0. It's worth doing so do it properly imho.

The seat may be able to do 0/0 if they put new hatches upstairs. Otherwise, they'll stay the 0/90 of the current seats. The upstairs hatches need 90 knots to blow off, the bus driver hatches have killed a defender in an uncontrolled ejection. Ejection has a very specific sequence that is a weekly knowledge question along with your boldface.

 

[NMaude]

The seat may be able to do 0/0 if they put new hatches upstairs. Otherwise, they'll stay the 0/90 of the current seats.

That's why they should replace the current hatches AND ejection seats with the US16E seat (Used in the F-35) also replacing the hatch with frangible panels like those in the B-2A would help.

 

[mkellytx]

That's why they should replace the current hatches AND ejection seats with the US16E seat (Used in the F-35) also replacing the hatch with frangible panels like those in the B-2A would help.

That would definitely be an improvement for the upstairs. The two defender seats are rear facing and would need different software nothing insurmountable.

 

[Ordovician]

"B-52 Re-engine Resurfaces As USAF Reviews Studies"
Oct 10, 2014 Bill Sweetman | Aerospace Daily & Defense Report

Source:

B-52 Re-engine Resurfaces As USAF Reviews Studies | Aviation Week Network

The U.S. Air Force is reviewing industry studies of fitting its 50-year-old Boeing B-52 bombers with new commercial-derivative engines, according to Lt. Gen. Stephen Wilson, commander of the service’s Global Strike Command. So far, Wilson said Oct. 9 at a Washington meeting, the Air Force...

aviationweek.com

This plane must be turns twin jet...maybe, I'm looking for an article from aviationweek & space technology that shows a sketch of a B-52 converted to a double deck for passengers plus a lower cargo deck. The drawing showed it with two very large engines.

 

[Byeman]

Considering that a lot of systems are being removed, new engines are installed (that have different controls compared to old ones, requiring a change in wiring), and other upgrades, might as well tackle this problem.

not in the same areas as the lower cockpit

 

[Scott Kenny]

As I understand it, it's not the aircraft structure per se. It's the wiring. For reliability, you don't cut the harness and then splice in a new extension cord going to the attic. (And despite what you hear, wire stretchers are apocryphal, along with five gallon buckets of jet wash.)

Instead, the old harnesses are stripped out of the airplane and new one are laboriously constructed on wire boards and then installed. After installation, the bundle is trimmed to fit and then pin-terminated with new connectors (Amphenol, thy name is ...). Then the whole system is hooked up to a DITMCO or equivalent tester for acceptance or repair. (Oh, I forgot the EMP test and certification cycle.)

Can you see the cost in this? It's the manual labor. (And those damn connectors that had to be put back into production.)

This sort of thing (major reconfiguration and replacement) is usually done only in a major system SLEP or system upgrade (F-4B to F-4N), or "tired wire" (declining physical reliability with advanced flight hours), or flight safety (early F-16A/B Kapton-insulated wire replacement).

Otherwise, the cost is very difficult to justify to the bean counters and congress critters.

Yeah, it's a major pain in the ass.

But with as much of an avionics change as is happening, I'd be surprised if there isn't a full forward wiring harness replacement going on.

The downward seats are good down to 200 feet and have been successfully used that low.

You will understand why reading that makes my butthole pucker...

 

[Foo Fighter]

The seat may be able to do 0/0 if they put new hatches upstairs. Otherwise, they'll stay the 0/90 of the current seats. The upstairs hatches need 90 knots to blow off, the bus driver hatches have killed a defender in an uncontrolled ejection. Ejection has a very specific sequence that is a weekly knowledge question along with your boldface.

Sorry, no idea what this (bold type) is on about.

 

[TomS]

Sorry, no idea what this (bold type) is on about.

Boldface refers to emergency procedures that are written in bold in emergency checklists and which flight crew are expected to have memorized and be able to perform without looking at the checklist. Weekly knowledge means it's quizzed regularly, so it should be absolutely engrained in the crew.