Armed to the teeth: B-70 with underwing Skybolts and SRAM internally

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As said in the thread title. There were talks about combining the (equally doomed) Skybolt and Valkyrie. Except it ran into a very stupid issue: Skybolt had been build for subsonic release.
Ok then, the B-70 would fly subsonically, launch the Skybolts and get ride of the pylons. And then it could go to Mach 3. Note that Skybolt had a range of 1000 miles.
I would say, a flight profile not unlike the SR-71 border penetration flights. Launch the Skybolts outside Soviet airspace, and then proceed to SRAM release before turning back (or not).

In 1960-62 obviously SRAM didn't existed, so the B-70 would have had gravity nuclear bombs in the internal bay. But how about SRAMs ?

Would have made a terrific weapon system...

Note that a Skybolt was smaller and lighter than the MA-1 pod carried by the B-58. A Skybolt / Hustler combination would have been something...
 
The B70 was designed to be a high atltitude bomber to dodge fighters. Once you have effective SAMs it loses that role. The B52H answers the problem. It can carry 4 Skybolts plus Quail/SRAM/bombs/kitchen sink etc. More.B52H models rather than B58s or B70s would have been a much better idea.
However, the B70 in its metal SAC scheme is one of my favourite planes and there were some ideas for weapons for it cooler than SRAM or Skybolt..My copy of Tony Landis is buried in a box but I am sure there are people here with ideas.
 
This one only replaced Quail but its still pretty cool
 
This one only replaced Quail but its still pretty cool

Er, no, actually as Pye Wacket was an air-to-air ATTACK missile not a decoy of any stripe :)

The actual problem of the B-70 and Skybolt was that the B-70 wasn't very good at subsonic speeds which was a major problem for a platform that would in effect be subsonic for a large part of the mission. Part of the reason the XB-70 was canceled in the first place was it was going to be a nightmare on airborne alert due to that little problem of being very in-efficient at subsonic cruising flight. Secondly Skybolt actually accrued little advantage on a supersonic platform in part because it had to be launched at subsonic speed, (there was some work on getting around that issues done but not a lot) and partly because Skybolt would not have benefited much from a supersonic launch compared to the need to redesign and rebuild the missile to utilize supersonic launch speeds. It would have cost quite a bit and delayed development even more which was already a problem.

Randy
 
Both system had issues

B-70 was expensive monster, if they had put in service it would have serve some years and like B-58
put out service because extrem high cost to fly a mach 3 Bomber Fleet.
Form that standpoint the ICBM are cheaper

Skybolt was more political victim
Testing of Skybolt had series of failures, in mean time the SLBM were more successful.
on wrong assumption ALBM are more vulnerable compare to Submerge Launch Missile, what let to cancelation by McNanara

Except the Skybolt would have given the B-52 and Vulcans or Victors chance to approach save to there launch points and Skybolt does final 1800km to target.
irony, the cruise missile that follow up Skybolt and SLAM was cheaper and had more range as Skybolt but slower

note on SLAM
the final concept was more kind doomsday weapon with 26 warheads
But Convair proposed the Big Stick a simpler smaller single Warhead version of SLAM
next launch with solid booster, they proposed B-58 as carrier aircraft for one Big Stick
this need supersonic speed to start the Nuclear Ramjet engine...
 
The B70 was designed to be a high atltitude bomber to dodge fighters. Once you have effective SAMs it loses that role.

How many SAMs are going to shoot down a Mach 3 bomber from 1000 miles away?
 
Once you have effective SAMs it loses that role.
SAMs would have a very hard time with the B-70 - not impossible, just very hard. The B-70 would have had a greater performance edge over the S-300 than the B-52 had over the S-75. The S-200 against the B-70 is more like an S-25 against the B-52 - enough to influence tactics, but not enough to seriously imperil operations.

The S-75 missile system inflicted something like a 7.5% overall loss rate on B-52s over Vietnam, with 7% the best single-raid performance. That's likely at the high end of what the B-70 would see. That's not to say that's a trivial loss rate. It certainly isn't. But it's plenty low enough to complete a strategic war plan, if you can only afford to put the things into service.
 
Woops my bad on Pye Wacket and the stand off missile. Its a while since I read my copy of Landis.
 
I would say
- standard B-70 delivering gravity bombs would
a) die to SAMs at high-level
b) fall short of fuel at low-level (or become a colossal target, perhaps worse than a lumbering B-52)

Now a B-70 with standoff SRAMs is a little better, although that missile range was unconfortably short.

Skybolt by contrast, with its 1000 miles range, indeed put the B-70 outside most SAMs envelope.

Alas, a B-52H with Hound Dog or AGM-109 (later) can achieve that, too. At far less cost and complexity.

Basically XB-70 + Skybolt would have been completely awesome but also somewhat overkill.
 
SAMs would have a very hard time with the B-70 - not impossible, just very hard. The B-70 would have had a greater performance edge over the S-300 than the B-52 had over the S-75. The S-200 against the B-70 is more like an S-25 against the B-52 - enough to influence tactics, but not enough to seriously imperil operations.

The S-75 missile system inflicted something like a 7.5% overall loss rate on B-52s over Vietnam, with 7% the best single-raid performance. That's likely at the high end of what the B-70 would see. That's not to say that's a trivial loss rate. It certainly isn't. But it's plenty low enough to complete a strategic war plan, if you can only afford to put the things into service.

Thats an interesting perspective. Had the B-70 entered service with SAC the primary defensive systems with which it would have had to have contend were the S-200 system and the Mig-25/R-40 combination. I won't make a judgement of their effectiveness against a B-70 at Mach 3 but neither was a slouch.
 
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I won't make a judgement of their effectiveness against a B-70 at Mach 3 but neither was a slouch.
The crucial consideration is that in a single-sortie nuclear operations plan, you can accept losses that would be totally unacceptable in a prolonged conventional bombing campaign.
 
How many SAMs are going to shoot down a Mach 3 bomber from 1000 miles away?
The Soviet answer to high speed US aircraft like A-12 & B-58 (and B-70) is MiG-25

Interesting is that SR-71 became main goal for MiG-25
So far is know no SR-71 was shut down by MiG-25 or SAM, thank to it's ECM system.
The B-70 would feature similar ECM systems, but i say before the B-70 would have extreme high operating cost.

For SAM
The S-200 (NATO SA-5) would able to intercept a B-70 flying near 300 km range, but ECM would protect the B-70.
The ABM-1 Galosh (NATO SH-01) would destroy certain a B-70, thanks it's nuclear warhead of 3 mega ton TNT
 
How many SAMs are going to shoot down a Mach 3 bomber from 1000 miles away?
The Soviet answer to high speed US aircraft like A-12 & B-58 (and B-70) is MiG-25

Interesting is that SR-71 became main goal for MiG-25
So far is know no SR-71 was shut down by MiG-25 or SAM, thank to it's ECM system.
The B-70 would feature similar ECM systems, but i say before the B-70 would have extreme high operating cost.

For SAM
The S-200 (NATO SA-5) would able to intercept a B-70 flying near 300 km range, but ECM would protect the B-70.
The ABM-1 Galosh (NATO SH-01) would destroy certain a B-70, thanks it's nuclear warhead of 3 mega ton TNT

Heck, even the original ISINGLASS (Mach 4.5 with ramjets, the son of Convair Fish / Kingfish) wouldn't survive a Galosh. In fact nothing below Mach 9 would survive it. That's what the NRO / CIA told Schriever back in 1965.

Hence RHEINBERRY - more or less a X-15-size rocketplane also dropped from a B-52, except with a big difference: XLR-129, a "proto SSME" with plenty of thrust and specific impulse, a good 445 seconds (instead of XLR-99 shitty 275 seconds). Push the propellant mass fraction as far as state-of-the-art, 1966, allows: around 0.80.

End result ? Mach 22, close enough from orbital speed (Mach 27, give or take) for the suborbital arc to extend nearly around the world (halfway at least).

B-52 drops RHEINBERRY near the coast of Spain (hopefully not above Palomares...) and the thing rockets like a meteor above USSR, PRC and Pacific ocean to land at Edwards.

I often wondered if A-135 (the ABM missile system around Moscow and Leningrad) could have shot RHEINBERRY. Its trajectory was far "flatter" and lower (200 000 ft) than the standard ICBM.
 
How many SAMs are going to shoot down a Mach 3 bomber from 1000 miles away?
The Soviet answer to high speed US aircraft like A-12 & B-58 (and B-70) is MiG-25

Interesting is that SR-71 became main goal for MiG-25
So far is know no SR-71 was shut down by MiG-25 or SAM, thank to it's ECM system.
The B-70 would feature similar ECM systems, but i say before the B-70 would have extreme high operating cost.

For SAM
The S-200 (NATO SA-5) would able to intercept a B-70 flying near 300 km range, but ECM would protect the B-70.
The ABM-1 Galosh (NATO SH-01) would destroy certain a B-70, thanks it's nuclear warhead of 3 mega ton TNT

So none.
 
I would say
- standard B-70 delivering gravity bombs would
a) die to SAMs at high-level
b) fall short of fuel at low-level (or become a colossal target, perhaps worse than a lumbering B-52)

Now a B-70 with standoff SRAMs is a little better, although that missile range was unconfortably short.

Not from Mach 3 and 80,000 feet.

Supercruise Pg 16.JPG
 
D'oh, I had forgotten than.

Would Skybolt get any similar boost ?
 
B-70 with Skybolt invulnerable to SAMs at 1000 miles away from its target - same goes for the much cheaper B-52 with Skybolt.
 
A B-70 flying at Mach 3 at 70,000ft and carrying 16 SRAM like missiles internally would be a very tricky thing to defend against.

The proposed 1958 production number of 250 aircraft probably would have yielded 4 wings of B-70s at a 45UE for each wing for a total active force of 180 aircraft, the later 200 number was based on 3 wings that would have generated an active force of 135. Arriving shortly after the Polaris and Minuteman barrage but before the B-52s penetrating at low altitude such a force would have been a significant additional complication for the Soviets.
 
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B-70 with Skybolt invulnerable to SAMs at 1000 miles away from its target - same goes for the much cheaper B-52 with Skybolt.

Except the B-70 is more useful after the Skybolts have been launched.
 
On a tangent, did the USSR ever deploy an equivalent to the AIR-2 Genie, be that unguided or guided? In an all out war such a weapon might prove effective against platforms such as the B-70.
 
A B-70 flying at Mach 3 at 70,000ft and carrying 16 SRAM like missiles internally would be a very tricky thing to defend against.

The proposed 1958 production number of 250 aircraft probably would have yielded 4 wings of B-70s at a 45UE for each wing for a total active force of 180 aircraft, the later 200 number was based on 3 wings that would have generated an active force of 135. Arriving shortly after the Polaris and Minuteman barrage but before the B-52s penetrating at low altitude such a force would have been a significant additional complication for the Soviets.

I'm not completely sure the B-70 weapon bay could carry so much SRAMs - 29 ft long (more exactly, 2*14 ft) and I can't-remember-the-width.
Still, interesting idea.
 
B-70 with Skybolt invulnerable to SAMs at 1000 miles away from its target - same goes for the much cheaper B-52 with Skybolt.

Except the B-70 is more useful after the Skybolts have been launched.

Which goes right back to the original issue: Skybolt/XB-70 ... Choose one as they don't compliment or augment each other at all and certainly don't improve either platform.

Skybolt's entire purpose was to put the US ICBM threat right outside the borders of the USSR on constant airborne alert. It didn't take very long to realize that was a very "offensive" (as in First Strike) posture that left a lot less room for error and mistakes. Plus, as usual the 'enemy' has to respond and frankly the probable responses were clearly only going to be more provocative and escalate the entire situation.

The XB-70 on the other hand was going to be expensive to build, expensive to maintain and expensive to use on a regular basis. (The B-58 was showing that issue and the B-70 was going to cost vastly more) There was also the question of vulnerability because even at Mach the B-70 was going to have to fly high the entire flight profile which made it visible and easy to track. (Even if we assume Blackbird paint to help hide it at altitude it's NOT going to be stealthy) And there's a similar note that if the attacker can accept losses in a total war so can the defender and likely they can accept MORE losses since they can plan ahead where best to take those losses. One of the main reasons that the SAM is listed as a reason that killed the XB-70 is because US research was showing that anything flying high, no matter how fast was vulnerable to the combination of responsive SAMs and nuclear warheads. (There was a pretty good 'reason' both the US and USSR had on-alert nuclear armed "satellite" killers through most of the Cold War and it wasn't for killing anything mundane like a spy satellite)

In context the XB-70 lost its mission to the ICBM because it was vulnerable and to point specific of a design to be repurposed. The Skybolt lost its mission both due to the ICBM and the to aggressive operational stance that airborne ICBMs represented once more practical and less vulnerable ICBM basing was developed. Worse the SLBM was far more effective and far harder to counter than the airborne ICBM and it didn't escalate the core standoff of the Cold War. Moving the whole idea of Nuclear Escalation back into the civilian rather than military hands.

Randy
 
D'oh, I had forgotten than.

Would Skybolt get any similar boost ?
It would certainly get some advantage - when thinking of ballistic missiles, it's useful to think in terms of delta-V, and air launch at Mach 3 and over 70,000 feet is probably worth about 1,000 metres/second.

As far as B-70 effectiveness goes, the USAF looked at it in 1961 for additions to the strategic force:

Their finding was that of the low-budget scenarios, twelve squadrons of B-70s were about as effective as thirty-seven squadrons of Minutemen, and would cost about the same. Buying B-52Hs or a combination of B-52Hs and Minutemen were a little behind. Anything involving more Titans was just a bad idea, and the Dromedary not much better.

The high budget scenarios found that 180 B-70s and 1850 Minutemen gave better results than just B-70s, though curiously they didn't study an all-Minuteman force.
 
the Dromedary not much better.

What... does this mean CAMAL, the subsonic nuclear aircraft ? o_O
Talk about a "codename" not to say "NAP" or "WS-125A" or "direct cycle - and radionucleides for everyone" ?

That website "alternatewars" is kind of treasure trove. As far as rocketry and missile goes.
 
What... does this mean CAMAL, the subsonic nuclear aircraft ?
I believe it was the conventional-power version of CAMAL. Not the most brilliant codename on either security or humour grounds.

...scratching my head trying to wrap my mind around that insane NAP thing...

What's the point in building a subsonic lumbering nuclear-bomber without the nuclear-engine that made it subsonic in the first place WHEN B-52 and B-70 are already there ? (bangs my head against a wall)

I mean,
WS-125A was to be "nuclear WS-110 / B-70"
and then...
CAMAL was subsonic after WS-125A failure - yet the nuclear engine still made sense at it (supposedly) made it superior to the B-52 for the Chrome Dome continuous airborne missions
(hint: no need for kerosene nor KC-135s, and there goes Palomares disaster... oh well forget it)
and then...
But a non-nuclear CAMAL is, well, a freakkin' B-52. So what's the point ?
 
In the 1961 report, the armament for the bombers is interesting - crediting the B-52 with four and the B-70 with eight gravity bombs, of 3 megatons each. To carry that many weapons they'd have to be MK-28 or equivalent Class D weapons, which are normally only credited with 1 to 1.5 megaton yield. And this isn't the only place I've seen that kind of yield attributed to a Class D weapon. Very curious....
What's the point in building a subsonic lumbering nuclear-bomber without the nuclear-engine that made it subsonic in the first place WHEN B-52 and B-70 are already there ? (bangs my head against a wall)
The USAF seems to have been attracted by the notion of a very long endurance conventional aircraft carrying standoff weapons even after ANP proved infeasible. In the 1961 study linked above, six Skybolts were carried. In a 1966 study, still using the name 'Dromedary', a 70,000lb manned low-altitude penetrator (!) was carried.

The 1966 version was designed around unrefuelled 100-hour missions with 74% of the fleet airborne at a time, compared to the 30% airborne on 24-hour missions that a B-52 could achieve. Exactly how this was achieved isn't clear from the report, it's not really the core subject matter. If it could be achieved, clearly that's a major improvement for airborne alert missions. And I strongly suspect the main target wasn't the Soviet Union but the United States Navy - Dromedary ALBM carriers would fulfil similar missions to Polaris submarines.
 
In the 1961 report, the armament for the bombers is interesting - crediting the B-52 with four and the B-70 with eight gravity bombs, of 3 megatons each. To carry that many weapons they'd have to be MK-28 or equivalent Class D weapons, which are normally only credited with 1 to 1.5 megaton yield. And this isn't the only place I've seen that kind of yield attributed to a Class D weapon. Very curious....
What's the point in building a subsonic lumbering nuclear-bomber without the nuclear-engine that made it subsonic in the first place WHEN B-52 and B-70 are already there ? (bangs my head against a wall)
The USAF seems to have been attracted by the notion of a very long endurance conventional aircraft carrying standoff weapons even after ANP proved infeasible. In the 1961 study linked above, six Skybolts were carried. In a 1966 study, still using the name 'Dromedary', a 70,000lb manned low-altitude penetrator (!) was carried.

The 1966 version was designed around unrefuelled 100-hour missions with 74% of the fleet airborne at a time, compared to the 30% airborne on 24-hour missions that a B-52 could achieve. Exactly how this was achieved isn't clear from the report, it's not really the core subject matter. If it could be achieved, clearly that's a major improvement for airborne alert missions. And I strongly suspect the main target wasn't the Soviet Union but the United States Navy - Dromedary ALBM carriers would fulfil similar missions to Polaris submarines.

I knew it. I knew the Air Force would not budge, never, ever give up to
- ANP cancellation, CAMAL mission
- Skybolt cancellation
- USN having the "ultimate nuclear deterrent" - Polaris
(that is: miniature ICBMs hidden in nuclear subs that can hide in the ocean depths and are so hard to search and destroy)
- Fact is that both French and British nuclear deterrents presently are only SLBM
(Rafale + ASMP-A is secondary, British airborne deterrent died in 1998 with the last WE.177) )
- Fact is that "nuclear-subs + Polaris" somewhat made obsolete - all by itself:
a ) B-52 Chrome Dome
b) B-52 with Skybolt
c) CAMAL ANP (with or without Skybolts)
d) B-70
e) Titan I & Atlas-F kerolox 1st generation ICBM
f) Titan II 2nd generation ICBM, storable props
g) and even solid-fuel but ground-based Minuteman silos (the basing issue)

There were so many variations on nuclear deterrent vectors, and it was the USN that got the definite one. I can imagine Curtiss Le May and Thomas Power anger and disgust. :)

-------------------------

Sorry, couldn't resist...

View: https://www.youtube.com/watch?v=VOmD-xqK2Es
 
Then there was "Strategic Earth Orbital Base" or more correctly "Cis-Lunar Deterrence System" more commonly, (these days) known as the Orion Battleship :)

I'll note I like how they article/author blames McNamara for following Kennedy and Congress' orders but as I keep pointing out what is fun to consider is the oh-so-close timing that could have been...

A year earlier Kennedy was casting around for suggestions on ways to show up the USSR in technology but was hesitant about choosing to go to the Moon due to the cost and complexity the program would require. McNamara was adamant that even going to the Moon was probably at to much risk of loosing to the Russians, he was pushing at a minimum an interplanetary mission but had to admit of the proposals from NASA and other experts the technology was not likely there. Now imagine that Orion comes across his desk at this point... Specifically with the Air Force more than willing to put up a major chunk of change towards development...

Randy
 
In the 1961 report, the armament for the bombers is interesting - crediting the B-52 with four and the B-70 with eight gravity bombs, of 3 megatons each. To carry that many weapons they'd have to be MK-28 or equivalent Class D weapons, which are normally only credited with 1 to 1.5 megaton yield. And this isn't the only place I've seen that kind of yield attributed to a Class D weapon. Very curious....

The numbers of bombs make sense. At this time the B-52 was flying with, or about to fly with, four Mk.28s in the forward part of the bomb bay and four ADM-20 Quails in the aft part of the bay. The B-70 effectively had two bays so the authors were probably assuming four weapons per bay for a total of eight. I agree that the 3 MT yield seems high though.

More curious is the assumption that a 200 bomber buy would generate twelve squadrons for four wings. Thats highly unlikely, based on procurement to Unit Establishment ratios for other SAC bomber types and public statements at the time 200 aircraft would only get nine squadrons making three wings.
 
In the 1961 report, the armament for the bombers is interesting - crediting the B-52 with four and the B-70 with eight gravity bombs, of 3 megatons each. To carry that many weapons they'd have to be MK-28 or equivalent Class D weapons, which are normally only credited with 1 to 1.5 megaton yield. And this isn't the only place I've seen that kind of yield attributed to a Class D weapon. Very curious....

The numbers of bombs make sense. At this time the B-52 was flying with, or about to fly with, four Mk.28s in the forward part of the bomb bay and four ADM-20 Quails in the aft part of the bay. The B-70 effectively had two bays so the authors were probably assuming four weapons per bay for a total of eight. I agree that the 3 MT yield seems high though.
Yup, definitely the thinking in terms of number of weapons. 3 megatons isn't out of the realm of possibility for a 2,000-pound Class D weapon. In fact, it's bang on the nose for a third-generation thermonuclear weapon comparable to the Mk-41 and Mk-56, if configured as a gravity bomb with full fusing options.

I'm increasingly convinced that there was a requirement for such a weapon in the time period in question, alongside the well publicised 60-megaton 25,000-pound Class A thermonuclear weapon. There are enough shadows of thinking on US thermonuclear weapons to outline a couple of capability gaps that don't correspond to any known or projected weapon, and this is one of them.
 
alongside the well publicised 60-megaton 25,000-pound Class A thermonuclear weapon

:eek: :eek: :eek: Edward Teller wet dream, I presume ?
Nope, a definite SAC requirement in 1956 which was being listed as armament for the B-70 as late as 1960. The yield/weight ratio is pretty comparable to the Mk-41, and the AEC was confident it could produce such a weapon.


It was intended for the counter-air role to reliably crater runways. I've realised that this isn't put a crater on the runway, in the way that we've become used to thinking about the task since the 1970s and conventional counter-air weapons. It's put the runway in a crater - the cratering radius for a 60 megaton ground burst is such that if it's delivered to the midpoint of a 10,000-foot runway, the crater will reach both ends.

I must put something up about the US thermonuclear weapons, though I'm not sure where it would best fit.
 
I really, really like the way you put it. I would have laughed like an idiot if not, well, huge nuclear weapons with colossal mass-killing power.

Far more "efficient" in a way, that the Port Stanley cratering by Black Buck Vulcan(s).
 
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alongside the well publicised 60-megaton 25,000-pound Class A thermonuclear weapon

:eek: :eek: :eek: Edward Teller wet dream, I presume ?

Heh, no in context, (since his idea that huge bombs were 'unthinkable" to use) that would have been the proposed Air Force "Strategic Deployment" Orion "ICBM" with a 4,000 TON (mass) warhead. The 'single' warhead version was actually pretty inefficient and there were a lot of questions about if such a large single device would even function.. So they looked at another version which carried 4,000 tons of warheads likely of 50 to 100 megaton yield with "enhanced" characteristics. Which one wonders why they decided to mount on an Orion as setting that thing off anywhere on Earth was going to be 'overkill' for the planet...

The eventually decided to just propose the Orion Battleship :)

BTW, "Atomic Rockets" has a new entry under the Orion category with an excerpt from a book called "Star Destroyers" (https://www.amazon.com/Star-Destroyers-Christopher-Ruocchio/dp/1481483099) specifically a story called "Boomers" by J.R, Dunn which is set in a universe where both the US and USSR deployed Orion "Deterrent" ships into space and takes place during a rather 'exciting' period in 1989 :)

Highly recommend!

Randy
 

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