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The XB-70 (2019)

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Re: The XB-70 (2019)

#61

Post by mrguyorama »

aerostable_slug wrote: post #55
rmnwski wrote: post #37

Earlier quoted context omitted.

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:

https://en.wikipedia.org/wiki/Rapid_Dragon_(missile_system)

Re: The XB-70 (2019)

#62

Post by nradov »

jiggawatts wrote: post #56
runjake wrote: post #4

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 o…

> 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…

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.

Re: The XB-70 (2019)

#63

Post by CoastalCoder »

runjake wrote: post #4

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 o…

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!

Re: The XB-70 (2019)

#64

Post by psunavy03 »

loloquwowndueo wrote: post #29
gedy wrote: post #17

Earlier quoted context omitted.

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..

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.

Re: The XB-70 (2019)

#65

Post by FpUser »

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.

Re: The XB-70 (2019)

#66

Post by 6stringmerc »

CoastalCoder wrote: post #63
runjake wrote: post #4

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 o…

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!

When I saw it, an SR-71 was parked under one of its wings. Talk about a stellar presentation of aviation engineering magnificence.

Re: The XB-70 (2019)

#67

Post by FpUser »

nradov wrote: post #58
rqtwteye wrote: post #12

Earlier quoted context omitted.

"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 th…

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…

>"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.

Re: The XB-70 (2019)

#68

Post by geoffeg »

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.

Re: The XB-70 (2019)

#69

Post by ianburrell »

mrguyorama wrote: post #61
aerostable_slug wrote: post #55

Earlier quoted context omitted.

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: https://en.wikipedia.org/wiki/Rapid_Dragon_(missile_system)

Rapid Dragon is using cargo aircraft for cruise missiles.

Re: The XB-70 (2019)

#70

Post by technothrasher »

CoastalCoder wrote: post #63
runjake wrote: post #4

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 o…

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.
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