As someone who once worked on B-52s, I find it amusing how many "successors" it has outlasted. And I know why, because I worked on many of those, too.
It has taught me to be skeptical of unproven claims and promises, especially when someone is particularly passionate about them. Also that simplicity is king. Complexity is the enemy.
I have great respect for the XB-70. It's the only strategic bomber I haven't worked on or even seen in person, and it holds a certain "alternate reality" mystique for me.
> Also that simplicity is king. Complexity is the enemy.
As someone that has managed engineering teams for large projects, I 100% agree. One of the issues with computers IMO is that it has made bad engineering easier. Back when you had to check everything with a slide-rule, you had a real appreciation for the skill and engineering prowess and experience to make things absolutely dead simple.
One of my favorite things is in the watch world, every mechanism besides showing time is called complication. When one talks about a feature, or an item as a complication, just the act of doing that forces one to be more deliberate.
True, but also modeling and iteration does lead you to unexpected solutions that can in turn solve complex problems that you couldn't have imagined could be solved. Landing rockets being an easy one, but that kind of iterative approach has been put to work in all kinds of fields.
One of the sources of this, which is now over, was the exponential increase in computing power. You could add complexity and your code would always run faster anyway, one of the popular benchmarks saw worse results on average than last year which never happened before. There are a lot of reasons for it some more speculative than others, and clearly computers will get faster in the future. But still.
No longer can software engineers arbitrarily add bloat and just get away with it.
https://www.tomsguide.com/computing/cpus/new-benchmark-shows...
"Also that simplicity is king. Complexity is the enemy."
That's what worries me about a lot of the shiny, super high tech, super expensive weapons systems of the US. These are fine against an overmatched enemy when you can fly back to a safe place for doing the necessary maintenance. This may change when there is a war against a capable enemy that can strike closer to home. The US has always had the advantage that the homeland was safe but that may change in the future. And once you lose a B-2 bomber it's very hard to replace.
It's literally impossible to replace a B-2 bomber: the production line was shut down years ago and much of the supply chain no longer exists. Existing B-2's (there are only 19 still in service) will be gradually replaced by new B-21 Raiders.
One of the long standing problems with US defense procurement is that they build a batch of something, then cut off all orders and dismantle the production line in order to free up funds to develop a successor model. This is tremendously risky because it leaves a gap of many years when it's impossible to replace attrition losses. If the US is going to maintain a credible deterrent against China then something has to change. Either defense spending has to go up or we have to drastically scale back activities in other areas. And no, cheap AI drone swarms won't replace the capabilities of something like a B-21.
>"If the US is going to maintain a credible deterrent against China then something has to change. Either defense spending has to go up or we have to drastically scale back activities in other areas. And no, cheap AI drone swarms won't replace the capabilities of something like a B-21."
Assuming the US would actually need B21 capability in a war with China. Those will be probably blown up from the sky very fast. Besides I doubt wars with China and / or Russia will be limited to conventional means. Will probably escalate to nuclear very fast and then everybody is royally fucked.
> Those will be probably blown up from the sky very fast.
Why do you say that? I'd think B21 is better (stealthier) than B2. I think there is a story about a B2 dropping a dud on NK undetected granted NK vs. China
I think any war with China would be predominantly economic and cyber. I don’t think it’s viable for either party to perform a mainland strikes and I don’t think it would become nuclear, but who knows. If things escalate during the current POTUS’s term, I think it will come down to meetings and deal-makings, because that is POTUS’s passion and preferred way.
I think any war with Russia would be, well is, economic and cyber and proxy wars.
They have one at the Air Force museum in Dayton.
I highly recommend visiting it for anyone interested in this stuff. It's an amazing museum, and it's totally free!
They don't have "one". They have the only one. The other one built crashed in 1966. The one in Dayton is all there is.
> Also that simplicity is king. Complexity is the enemy.
I don't know anything about B-52s, but I work on a project where we are essentially replacing a 40 year old weapon system with a new one. The new one should of course do the same things, preferably better, and do additional new things. The old system started out simple, but has since had most of its internals swapped both hardware and software wise a number of times. We have full access to all the documentation of the old system, but let's say there has been periods throughout these 40 years where this aspect hasn't exactly been top priority.
It doesn't come as a surprise to me that projects like JSF end up a complete clusterfuck. Everyone tends to underestimate the complexity of the system they operate/produce after a while because most of it is always there and just works.
> ...especially when someone is particularly passionate about them.
The engineer-type brain is very much prone to "... in order to prove we can," as opposed to "Because we should. Or because this is useful. Or because this even does the job claimed."
Across a range of fields. A/B testing "engagement hacks" falls into this category, as far as I'm concerned. It was certainly successful at the stated goals.
I am in awe of anyone who worked on bringing forth such projects into the world. In the mean time, in my little corner of the world, a team of people are struggling to conjure up a relatively "simple" website.
I was watching a documentary about 20 years ago and they said "It may not be your father's air force but it may be your father's air plane."
I agree with you, but the issue afaik is that B-52 was more flexible whereas the B-70 was basically single purpose and basically obsoleted by ICBMs.
B-52s were able to pivot to new roles so have stayed around.
I'm humbled for us laughing at the one guy assigned to B-52 maintenance role when was in USAF training over 30 years ago "That old thing? Ha!". Who would have guessed..
> I'm humbled for us laughing at the one guy assigned to B-52 maintenance role when was in USAF training over 30 years ago "That old thing? Ha!".
That guy may have been me. I was pretty bummed, but quickly learned about its awesomeness (avionics-wise, anyway).
You may find this amusing then. I was at Travis for a day (from McClellan) and I had time to stop by their museum. They had a G model on display and there was an older gentleman with a child looking at it. "What kind of plane is this, grandpa?" "I'm not sure - I think it's a cargo plane"
I had a really tough time resisting the urge to tell them the "cargo" came out the bottom.
Ha, at Lowry in 1993?
Yep, up until January 1993 or so.
"SRAM Howell" ring a bell?
Ah I got there 1/93 so may have missed. I remember going to "fundies", getting called "pinger", etc. Good times.
Nobody can understand our fear of washing out and moving to the other side of the dorm to become a food handler and serving your former avionics classmates breakfast. This happened a lot while I was there.
Lol, I forgot all about that - though there were some cute chicks over there. I remember chatting with one about her upcoming French Toast test :-)
What killed the xb-70 was the advent of better air to air missiles that nullified its high-altitude high-speed flight advantage.
ICBMs also render other kinds of bombers obsolete and yet b52 and tu-95 are still around.
> ICBMs also render other kinds of bombers obsolete and yet b52 and tu-95 are still around.
This has been proven utterly false since the 1960s, because a) you can't recall an ICBM after firing it, b) you can't retarget an ICBM after firing it, and c) there's no reliable way to tell nuke warheads from conventional ones, meaning every one you launch has to be assumed to have a nuclear payload, with all the world-ending consequences that entails.
The Air Force resurrected this zombie idea (conventional ICBMs) in the 2000s and called it Prompt Global Strike, only to can it for the obvious reasons.
From what I know, what actually killed the XB-70 was ICBM advancements.
The B-52 survived by becoming a low altitude bomber and an excellent, cheap nuclear-capable cruise missile delivery platform that was comparatively cheap to operate at the same level of effectiveness as the B1-B and B-2A for similar roles.
Russia more or less mirrored this with the Tu-95.
The B52 was never a low altitude bomber, you're thinking of the B1A, which was to be a high altitude, super sonic bomber but SAM missile tech advanced faster than the development of the bomber could happen, and it was canned, before being resurrected as a subsonic, low altitude bomber (the B1B). The XB-70 couldn't make that switch because it was a ridiculous design (for starters).
The B52 role was to have wings (and nuclear bombs) in the air constantly over the arctic to act as a deterrent. The only way that idea could attempt to survive out of the 50's is if they (or one of them) were < hour from a target at all times. They're huge, they flew slow, and their flight path didn't change much. The whole multi-decade mission was a huge waste of money; a stage drama.
The B52 also became a heavy bomber in Vietnam, with incredibly heavy loses. The Air Force in general in Vietnam was a shit show -- observe the F4.
It's only when you have air superiority can you dredge up a B52 to deliver a payload.
These are not winning strategies in a war that would start today by an adversary like China. We're going to be caught with our pants down with B52s as the stains on our underwear.
> Also that simplicity is king. Complexity is the enemy.
Which sounds good, but the B-52 planes used eight very old jet engines each that are complex to maintain.
Rolls Royce offered to replace these with four modern turbofan engines but were turned down.
They finally relented and there’s a new program that will run to the end of the 2030s(!) to replace the eight engines with… eight engines.
This doesn’t sound simple, or cheap.
I keep pointing out to people that if a real world war broke out, every country with a commercial wide body fleet will immediately convert them to bombers. Far cheaper, far simpler to maintain, and with much faster turnaround times / lower maintenance hours per flight hour.
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.
Not to make this thread about the B-52, the thing has been operational long enough for 3 generations from one family to fly it: https://www.dailymail.co.uk/news/article-2430802/David-Welsh...
I always wondered why the B-52 didn’t get replaced by converted airliners (787 has quite similar dimensions I believe). Would be much cheaper to run and could do practically the same thing, no?
There was thought given to using 747s as cruise missile carrier aircraft.
Each 747 CMCA would have carried dozens of AGM-86 nuclear-armed cruise missiles on rotary launchers that shuffled around the plane's cargo bay on rails (the missiles would be ejected one at a time from a small door near the rear of the fuselage).
Which was an interesting idea, but it eventually evolved into a much much better one:
Rapid Dragon is using cargo aircraft for cruise missiles.
They look the same to a layman, but they are very different airframes, with a different wing sweep and different load capabilities, among many, many other differences.
not really.
That era of aviation was nuts. I wish I was around for it. Men with slide rules working out the limits of material science, aerodynamics, and everything else, all at once. Because it wasn't enough to just push one limit, you had to push half a dozen others to get things to that first limit. And the rate of advance was just staggering.
The XB70 flew in late 1964. Concorde was doing revenue flights in 1976, cruising at Mach 2, with passengers being served luxury food.
> The Air Force learned that pushing the technological envelope resulted in plane that was difficult to build, difficult to maintain, difficult to fly, and perhaps even more importantly, was incredibly expensive; the program cost nearly 1.5 billion dollars, or around 11 million dollars per flight.
And nothing has changed. Pushing the limits is expensive. Always has been, always will be.
My favorite bit of design from this era went something like this: "ooohhh, we need something that can handle high heat. How about if we made it radioactive?" and so Mag-Thor was born (https://en.wikipedia.org/wiki/Mag-Thor): Magnesium plus Thorium. It's creep resistant up to 350C! And it's only mildly radioactive! That's not a problem, right?
Actually used on the BOMARC and D-21's ramjet engines- which is why you don't originals of their engines on display anywhere.
Mag-Thor is interesting it actually has rather poor overall thermal characteristic compared to most metals since its melting point is only circa 650c pretty much the same as magnesium but it basically shrugs any heat upto 350-400c depending on the alloy so it doesn’t changes its dimensions or becomes susceptible to mechanical deformation (it’s basically as hard at 350c at it is at room temp). So it’s useful but only for very specific applications unlike say titanium. And today we have super alloys like inconel which can hold back heat creep up to 650c and it’s annealing starts at almost 900c.
They tell the most pernicious lies about radiation.
The sheer amount of gas this plane must have carried in order to fulfil its mission…
Per Wikipedia, the XB70 carried: 300,000 pounds (140,000 kg) / 46,745 US gal (38,923 imp gal; 176,950 L), on a maximum takeoff weight of 542,000 lb - so about 55% of takeoff weight was fuel.
A 747-8I carries up to 63,034 gallons, or about 400k pounds, on a max takeoff weight of 987,000 pounds, or about 42% of takeoff weight.
Interestingly, the ranges are about the same. The XB70's combat radius (there and back) is 3,725 nm, for a straight line range of 7450 nm, the 747-8I's range is 7730 nm.
High altitude supersonic flight is actually fairly efficient... if you can handle it.
Was the XB-70 capable of inflight refueling? On a quick look, I can’t tell if that was the plan, or if it was going to be a one-way trip (optimistically landing in Turkey or something to refuel, but realistically…).
I don't believe it was capable of it, which is why it was so massive. The SR-71, which required inflight refueling repeatedly, only held 80k pounds of fuel (about 12k gallons). I don't have any good sense of fuel burn vs speed either, but in general, jets like to run high and fast. The old Lear 23s burned about as much fuel (pounds per hour) idling on the ground as they did at cruise, and I think the SR-71 (which mostly used the turbojets to keep the afterburners lit, at cruise...) fuel economy up high was quite good. Apparently the major problem with performance was keeping it from overspeeding - left to their own devices, the engine (... entire engine assembly, however long it was) was running so efficiently that they just wanted to go.
I have a love/hate relationship with this plane.
In 2014 I got to visit the AF Museum in Dayton, OH. With all the exceptional exhibits there it is completely obvious the XB-70 is THE crown jewel in that museum.
And it snowed while we were visiting and they shut down the hangar with the XB-70 because it required a shuttle ride.
So now I still have on my bucket list to see it.
I went in 2010. Took the bus onto the air base to the experimental plane hangar. We only had 1 hour. I could have easily spent 3 hours there.
I mainly wanted to see the YF-23 but here's a pic I took with a fisheye lens of the back of the YF-23 with the XB-70 above. I think they have since moved the planes to a different hangar.
I have a love/hate relationship as well, mostly because I grew up within bicycling distance and spent way too much time at the museum.
The XB-70 used to be parked outside right in front of the main entrance. The cool thing is they also have the X-3, which seems like the same design family so you can see the test article then the attempt at a usable aircraft.
It was also the location of one of the most bonkers thing I've ever seen which was when they relocated an SR-71 to the museum and landed it on this very short old runway at the site. That thing was so big and so fast and that runway even at the time seemed so short. Here's a vid. I saw it from the road off the end of the threshold and it looked like it was going to hit the fence on the landing pass.
we lived in rona hills for about 4 years. not biking distance, but close enough to visit frequently. and as a youngster they let me conduct the AF orchestra there at the AF 25th anniversary. Very good memories.
Go back, it's so worth it. I stood under those six massive turbojets and looked up in absolute awe. It's a miracle that they didn't cut it up for scrap and left a really fabulous museum piece when the project ended.
Because we're not the British or Canadians who felt they had to make their military R&D decisions irreversible by destroying all the evidence (e.g. TSR2, Avro Arrow, etc).
In fact there is a TSR-2 at the Imperial War Museum Duxford.
It was a violation of orders as all airframes were explicitly ordered to be destroyed and burned.
The AF Museum is probably the best air museum in the world. Of course, you have the Smithsonian in DC, but the size limits and general audience they expect really tones it down. You end up with a couple insane exhibits (Command Module, X-15, Wright flyer) but they all feel out of context. I actually preferred the annex with the Shuttle more.
The AF museum is our modern history and society shown through the lens of the air and is insane in size.
Always good to have a reason to return.
(I tell my family that on every stop on our road trips & vacations.)
The only time I went to the AF Museum was in the early 80s while in grade school. I still remember that thing. It was the coolest thing I'd ever seen. I was completely floored.
The ejection capsule design for the XB-70 is some next level engineering. Your seat would move backward into a capsule before ejection to survive the cruising altitudes of 70k feet / Mach 3.
https://www.generalstaff.org/CDA/Air/B-70/XB-70_Escape_Syste...
"got a job with the Flight Propulsion Division of General Electric in Evendale (just outside of Cincinnati), initially working night shift in the Controls and Accessories department... the engine required the efforts of hundreds of engineers to design everything from a new turbofan and compressor, to new fire-suppression systems, to a special high-temperature fuel. Exactly what part my dad worked on is unclear; I always thought it was an oil pan, but my older brother was sure it was an oil pump."
This small detail peaked my curiosity - did GE have white collar workers on the night shift? If so, that is super interesting to me.
Yes, there is often manufacturing engineers on duty 24/7 and of course, line management.
I've seen the XB-70 at the Dayton Air Force Museum and each time it seems both massive and relatively svelte. Like some kind of shape that I can't quite fully understand. Really cool plane to see, especially among all the other aircraft from that era of aviation.
The Cold War era was the dream of engineers of all participant countries, I figured. Are we close to another one? Just wanna make sure it doesn't turn into a hot one.
yup, there was just so much money flowing around. it was like the dot com era for aeronautical engineers and machinists.
“…Eisenhower, the newly-elected president, was working on something a little bigger: a national security policy to counter the growing Soviet military threat in Europe.”
The good old days.
Does anyone know why they went for six engines rather than four bigger ones? Was there a specific reason for that config?
A beautiful plane, shame those 6 engines in line is unreal to see.
Similar vibe would be the B1-lancer for engine although in 2s
The Wings Over the Rockies museum on the east side of Denver CO has a B-1A (!!!) on display. Landing gear is really tall, you can walk under the wings to see the engines.
I watched a really cool walk around video of it on YT
It's crazy it can carry as much payload as a B-52 if I recall right
I remember seeing this beast at the Air Force 25th anniversary in '72 at wright pat. Pretty sure the one I saw didn't ever fly again.
The one you saw was the only one left after the insane accident that destroyed the other. It is still on display in Dayton.
I normally do not read blogs. Yours is different. I loved your stories. Salut to your dad. Life well lived. Also thanks for pointing to Vivian Della Chiesa. Listened few songs on Youtube - great artist.