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The Air Force is having to reverse engineer parts of its own stealth bomber

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Re: The Air Force is having to reverse engineer parts of its own stealth bomber

#111
One of my aerospace professors in college used to be the secretary of the Air Force and B2 development started during his time in office there (back when Carter was president). I remember him saying that one of the missed opportunities in his opinion for the U.S. was not buying more B2 bombers. They can reach anywhere on earth and we only have 20 of them. But Congress didn’t want to keep making them after the Cold War.

Re: The Air Force is having to reverse engineer parts of its own stealth bomber

#112

The B-2 is ancient, doesn't seem very surprising.

It is by no mean ancient. The introduction of the B-2 in service was ~24 years ago, this is one of the most recent jet in the US air force. By military standard it's definitely young. There are only 2 planes in service in the US more recent than that, the F-22 and F-35 (not counting transport aircrafts). Those planes are designed for lifespans of 50-100 years.

> Those planes are designed for lifespans of 50-100 years.

No, they weren't "designed" for a century. Think about it for a minute - would a military contractor even admit it if they did? There would be no new programs. :)

The reason the B-52, F-16 (and T-38 for training, F-5 for aggressor training, etc.) are still around is because they were made in quantity.

By contrast, the F-22 had a run of about 190 airframes, and the B-1/B-2's dozens each, with only a handful (like 3 - 5) of each model operational at any given time - it's really that bad.

All they had to do for the B-52 was to update the avionics and add a cruise missile rotary launcher in the bomb hold. (Believe it or not, that is the main thing that keeps the B-52 in operations.)

B-52 Rotary Launcher Video https://www.youtube.com/watch?v=-hCjO43k-1Y

Re: The Air Force is having to reverse engineer parts of its own stealth bomber

#115

This brings up an important principle: the higher the tech, the shorter its lifespan. A cellphone from the 1980s won't function anywhere but in a Faraday-caged lab equipped with a suitable cell site, while 2G and 3G systems are fast disappearing. Only recently have landline telephone exchanges begun to drop support for pulse dialing, but otherwise, a rotary-dial desk phone from 100 years ago would still work today, a…

> a rotary-dial desk phone from 100 years ago would still work today

This still amazes me, even though every time a call comes in on the landline, the 50-year-old rotary-dial phone in my living room rings alongside the cordless phone. It doesn't get used much, except for the loud ringer and during extended power outages.

Re: The Air Force is having to reverse engineer parts of its own stealth bomber

#116
I can't be certain, but I suspect the real problem was that the original contract was signed without requiring the technical data rights and/or delivery of the technical data. This is a common mistake made by the DoD, and can lead to extraordinarily high costs later.

Just look at the notice: "The deliverables will include all technical data related to the heat exchanger disassembly, all technical data related to the cores, all technical data related to the stack up, vacuum brazing, and installation of the cores on existing units. The deliverables will also include all technical data related to the tooling needed..." It's clear they don't have the technical data.

Here's how this can happen: the government asks for proposals, and the prospective contractors say "we'll create it for you for cheaper if you don't require the technical data & its related rights". The government program manager (PM) is under a lot of pressure to "get it cheaper", and this is cheaper in the short term, so the government PM agrees. The PM will be around for a few years, then leave. Later on, the contractor is the only one who can make the parts (because they're the only ones with the technical data & the technical data rights to do it). The government procurement system is all about competition, but now there is no possibility for real competition. Thus, the parts will cost 10x or more, and the government PM who approved this is long gone (probably with a promotion), and the contractor is happy with incredibly large profit margins.

I don't know if that's what happened in this case. But it's very very possible.

Re: The Air Force is having to reverse engineer parts of its own stealth bomber

#117
post #3

Reverse engineering seems like a good skillset for the DoD to nurture, anyway. Yes, the US is going to be at the cutting edge of weapons design at least through the medium term, but the leadership isn't arrogant enough to think that all engineering innovations will come domestically. If the US acquired a next-generation Chinese fighter, wouldn't it be handy if someone had the expertise to tell you exactly how its par…

I don't think this kind of thing is all that uncommon for military airplanes that have been long out of production. I recall reading a decade or two ago that our local air guard wing had to fabricate some of its own replacement parts for its F-16s (IIRC, then some of oldest that were still in service). I also recall that Lockheed had to take special effort to preserve production know-how and tooling for the F-22 when…

A friend of mine looked into building a P-51 from scratch, as buying a real one was too expensive. He ordered the blueprints, which are readily available. But then he talked to some P-51 owners, who told him the blueprints wouldn't be much use. The airplane was defined by the jigs used to build it, and the blueprints were just drawn up later as documentation and never checked. The jigs were scrapped when the airplane went out of production.

Re: The Air Force is having to reverse engineer parts of its own stealth bomber

#118

I can't be certain, but I suspect the real problem was that the original contract was signed without requiring the technical data rights and/or delivery of the technical data. This is a common mistake made by the DoD, and can lead to extraordinarily high costs later. Just look at the notice: "The deliverables will include all technical data related to the heat exchanger disassembly, all technical data related to the…

I wouldn't be surprised. It has happened with a lot of different acquisition programs. That was actually one of my first thoughts on reading the article, as I know people who've had to do this kind of reverse engineering for other aircraft due to a lack of tech data in the initial contract and refusal of USAF to purchase it later.

Re: The Air Force is having to reverse engineer parts of its own stealth bomber

#119

Earlier quoted context omitted.

My dad was talking to an engineer at one of the major airlines manufactures apparently some critical part was foam injection or some such. Anyway the process as such did not work as documented. You had to add strings to the inside of the mold to get it to set correctly. This was not written down anywhere. Part of it may have been job protection. The union was bad about that. New hires would not be able to complete th…

It's also possible it was "Hey! The foam injection machine isn't working, I've tried everything", "There's this string trick I used once, try that", "Great, that fixed it, we should document that", "Sure, once we get all parts made that have backed up" Or, maybe I'm reading bad practices in my industry to everywhere else.

I've seen that way too many times. "Why doesn't this link in the internal console work?" "Oh, after you click it and get the error, you have to remove the trailing dash character and refresh." "Weird, I wonder how this slipped by Jared in QA when he tested it. We better let him know." "Don't bother, Jared is the one who showed me how to remove the dash...."
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