It's always disappointing to see such uninformed and yet overconfident comments on HN. Replacing the eight small B-52 engines with four larger ones was considered and rejected years ago because it would have forced much more extensive modifications to the airframe and other systems.

https://www.twz.com/6825/engine-falls-off-b-52-during-a-trai...

And it's extremely difficult to convert civilian airliners into bombers. The pressure hulls aren't designed around bomb bays and they lack external hard points. Even though the P-8 is based on the 737 the design had to be extensively modified to accommodate weapons through a major program lasting years. The resulting aircraft are new production, not modifications of airliners.

You're saying that my argument that "8 engines is not simple" is invalid because... it would not be simple to replace them with modern efficient engines... because there are 8 of them.

Yes. We agree: the setup is not standard, not simple, and requires 2x the maintenance that 1/2 the engines would for decades and decades.

Older and established isn't necessarily "simpler" or "cheaper".

The average annual maintenance cost of a B-52 is $70 million.

The maintenance cost of a 747 or a similar sized plane is more like $4 million, and they operate far more hours than the B-52 fleet.

A commercial plane equivalent to a B-52 costs something like $200M to purchase new, which is just three years of maintenance for a B-52!

Sure, sure, the out-of-the-box default for a commercial wide-body airliner is not immediately usable as a strategic bomber, but it's not that hard to add a bomb bay, in-air fuel port, etc...

You are comically off-base on this, man.

We are talking about a nuclear bomber. They put fucking nukes on these things. We have 70 years of operational history showing that the 8 engine arrangement works, and there is no good reason to make anything more than the most minimal changes. Go ahead and do that until you're blue in the face with some inconsequential junk SaaS product or phone app or whatever, but warplanes (and especially this one) are not the place to do it.

I'm just going to hope you're not actually serious about converting a commercial airliner to a bomber.

The bomber isn’t nuclear.

The payload is.

The good reason to make changes is the hard reality that your opponents won’t slow down to accomodate your old, inefficient, maintenance-heavy fleet of bombers.

Even during peacetime the B-52 fleet is burning money, money that DOGE assures the voting public cannot be wasted on frivolous matters such as HIV prevention.

It’s like the Ukraine war. Perfectly good tanks turned out to be useless sitting ducks in the face of $500 drones.

Why change anything?

Because the enemy did.

Because the rest of the world did.

Wow, you're really doubling down on the aggressive ignorance. Do you have any clue about what's involved in certifying a platform for the nuclear strike mission?

Making such a plane, yes, I have a pretty decent clue. It's not that hard. It was done with early 1950s technology!

Certifying, sadly... also yes. I work in government.

Do you think the enemy cares whether you're properly certified or not?

Similarly, do you think hackers care if your CISO has all of your security audit paperwork nicely rubber stamped?

Do viruses care if your unpatched servers have been officially exempt from the update schedule?

In war, only capability matters. Nothing else.

There's quite a bit of extra hardware needed on the aircraft for the nuclear mission. As well as testing for stuff like weapons separation. None of that is easy or cheap on converted civilian designs.

You would know this if you had bothered to do some basic research instead of posting ignorant and irrelevant comments. Like many arrogant engineers who love to pontificate about topics outside your area of expertise, I'm sure you're convinced you're right and everyone else is an idiot. So I'll pass on any further replies and let you believe that you "won".

Go do the research yourself please and link to articles that explain why carrying a cruise missile with nuclear warhead instead of a high explosive warhead adds $60M in annual maintenance costs to each active bomber.

If your assessment of role of armor in Ukraine is that it's useless because of drone developments, you're just not playing with a full deck of cards.

You can think what you want and I can't stop you, I just want to say that you shouldn't bring this up around people that do real engineering (especially in aerospace and defense) unless you want to look like an idiot.

They would be busy ferrying troops and supplies. Amateurs talk about tactics, professionals discuss logistics!

You can't replace them with 4 engines because those will have to be of bigger diameter and they might scratch the ground of some less than perfect airfields. The engines HAVE to fit into the same nacelles. And they have to provide enough thrust while having same diameter -> this is hard because the goal of replacement is efficiency, and you replace a low-bypass engine for a high-bypass to increase efficiency, which means that hot section must be smaller, and thus able to survive more heat and pressure.

Previous programs of B-52 re-engining indeed, tried to replace 8 engines with 4. It never worked because of diameter/ground clearance issue. They had to wait until progress in aircraft engines allowed for the engine of same diameter to provide the necessary efficiency boost.

By the way, re-engining will vastly reduce air refuelling needs, and further extend airframe life because of lighter takeoff weights, as they won't need to take as much fuel on most missions. And in a pinch, almost any mission will be doable without refuelling at all.

In a peer war it's pretty damn dubious whether a B-52 with four modern engines will be more survivable than a B-52 with 8 antiques. Either way the most they'll be able to do is launch standoff munitions from a distance they hope will keep them safe, and if it doesn't then they're dead anyway. In a scenario short of that, we're just quibbling over the degree of waste American voters will put up with (it's the military, so the answer is a lot.)

That's pretty much irrelevant. Engine replacement is about increasing range and/or reducing tanker requirement/airframe wear, and reduction of maintenance costs because existing engines are ancient and their maintenance costs are high. One of the reasons this program has been postponed for so long was retirement of C-141 that left USAF with plenty of still good TF-33s. But now these are starting to run out too.

You're right, I intended to reply to the comment saying "In war, only capability matters. Nothing else". I don't think the engine replacements would/will meaningfully sway the balance of capabilities.