British Stand Off weapons


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From BSP.4

Developed to OR.1182 - 1,000nm range, Mach 3 performance at high altitude, and high-speed (mach 2) terrain following for the last 100nm to be in service by 1966.

Bristol X.12 (also known as Pandora) – This low-level stand off bomb had a slim 50ft (15.2m) long fuselage of just 3ft 2” (98cm) in diameter together with small delta wings 15ft (4.6m) long and 6ft (1.8m) span. The latter, and a semi-integrated BS.10-13 ramjet optimised for Mach 2.5, were mounted around the rear fuselage; a 28ft (8.5m) mid-fuselage section housed the fuel and the nose contained the warhead and guidance (Forward Looking radar from TSR.2). At 20,000lb (9,072kg) weight, X-12’s range would have been at least 1,000nm (1,852km); maximum ceiling was expected to be 70,000ft to 76,000ft (21,336m to 23,165m) and initially, a cruising speed of mach 4 had been planned. Projected in-service date was 1966.

Avro W.140 – This had a slim body 37ft 3in (11.35m) long with a 6ft 6in (1.98m) span delta wing, a Rolls Royce RB.153-17 jet and all-moving elevons for control aft of the wing. Launch weight would be 8,550lb (3,878kg). If the weapon was launched at mach 0.84 and 45,000ft (13,716m), a range of 1,550nm (2,871km) was possible but this fell to 950nm (1,759km) if the missile flew the last 100nm (185km) at Mach 1.5 at sea level; W.140 would cruise at Mach 3 at 70,000ft (21,336m).

Later on the Grand Slam and Grand Slam II were proposed to a different requirement

BAC at Filton also looked at larger weapons. Two were proposed: Grand Slam and Grand Slam II for the longer-range mission. The former was a 100nm (185km) range rocket-propelled toss bomb to be launched from TSR, while the latter definitely did not fall within the RAE’s size category. Grand Slam II took the toss bomb and added extra. With a launch weight of 32,000lb (14,515kg) and a length of 50ft (15.2m), Grand Slam II could only be carried by the V-bombers. Its 1,300nm (2,408km) range was achieved by flying at Mach 3 for the first 500nm (926km) at high altitude, descending to low level and Mach 2 for the next 700nm (1,296km) before pitching up to toss the Grand Slam onto the target from 100nm (185km). Power for the weapon would be provided by an integrated BS.1013 ramjet fuelled by a high-density/low volatility fuel such as Shelldyne, then under development for high-speed ramjets.

Now all these were nuclear armed, but does anyone know what the warhead weight would have been?
Ok, this seems like the best thread to ask this as PMN1 has already posted a lot of the details.

Why did the RAE take such a dim view of the W140??? I have ready the reasons given in both BSP4 and Vulcan's Hammer but they do not seem to stack up with the posted statistics. The only one that seems valid is the low altitude speed, otherwise the W.140 appears to offer everything the X-12 does but at a dramatically lower weight and with the turbojet/turbofan that had been preferred for the Blue Steel Mk2/Phase 2 projects.

The only other explanation is that Avro grossly overestimated the potential of the W.140 design?

Anyone have any thoughts?
These 2 threads (with Space) dealing with Brit schemes dredge up kite dreams from industry and RPE sources. Paymaster MoS was lukewarm, Ministers were cold...and the airframe-centric parents of all UK GW teams were frigid: GW made no business sense. Unguessable R&D resource/time, for modest production volume, and likely modest, if any, lucrative exports. RAE pimped GW in ’48, urging firms to “detach some of your best men to work on something which is a doubtful starter, politically vulnerable, and perhaps even unprofitable”. For (to be) Thunderbird EE was chosen as vertically-integrated Prime: they accepted conditional upon not having “to put capital into the venture”. In practice remote from Group kin Napier (motor), Marconi (guidance), their reward at (Napier) Luton was to “put up their own buildings - or more accurately (MoS to fund) the operation”, inc. a new Stevenage site, later core (to be BAe.Dynamics/)MBDA A.R.Adams, Good Company, BAC, 1976, Pp4/28/61. Special Products appendage in 1960 at Vickers as BAC was formed: “junior partner of the Aircraft side (a) poor relation.” Special Director/Weybridge G.Edwards “wasn’t particularly interested in GW” Adams,P70.

MoS, 1955 for Blue Steel was “relieved (to find in Avro an A/c) constructor (prepared) to accept the challenge” J.E.Allen(Avro),Blue Steel& Devts,R.Ae.S 17/3/99. But quite soon Sir Roy Dobson could not see payoff to match the pain; production volume gently evaporated; owner HSAL bought DH for its Blue Streak business just in time for it to be cancelled, so little appetite remained to indulge Avro/WRD to do more origami darts. “few (contracts caused) such bitter feelings (as) even in ’56 (Avro puffed 1,000n.m. The view in MoS was that if they) could not perfect (100n.m.) how could they (do) 10xthat? (Weapons Research Divn, many ex-RAE staff untutored in matters of money) weak management structure (criticisms,) recriminations (were) common parlance” Wynn,P202/4.

The prime reason that projects in Chris Gibson's BSP/Hypersonics and now Vulcan's Hammer (extensively drawing on EE/Preston and Avro WRD doodles) are a) stimulatingly new to us, and b) origami, is that Ministers knew them all to be beyond the wit of the procurement process to deploy in the decade, nay century, of first funding. The wonder is not that Ministers did not proceed with so many, but that they did persevere with any. They became locked in to Seaslug and Blue Steel on platforms that, they were told, could not take US equivalents.

Here's a provocation for Brit GW/Space fans: name one project brought to the User on time, on Spec., on budget. And that continues. Even after BAE melded UK GW into MBDA, Meteor, for example, will be in its 3rd (do I mean 4th.?) decade before IOC. And if you concede the point do not whinge about dithering Ministers. Vast cascades of money, and infusion of Other Peoples' Industrial Property. If Ministers had not made 20-27 February,1950 US/UK (“Burns/Templer”) GW data Agreements, there would have been no UK GW industry.
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On budget, on time ... Polaris?
I take umbrage at being described as a "Brit GW/Space fan". Most here should now be well enough informed to understand the deep structural problems that afflicted UK industry from the late 30s onwards and the policy, economic and doctrinal issues that prevented the procurement of the wares that industry would not have been able to provide anyway.

Indeed ken, you and others, including myself have provided considerable input into removing the myth of ministerial ineptitude and malicious conspiracy in the decline of UK A&D industry. However, that does not prevent one from having an interest in the systems and platforms they proposed as after all they are part of the same story.
One must never under estimate bureaucratic politics.

Reading the OR 1182 file is interesting. Being a air breathing missile, the question arose as to its vulnerablility [Blue Streak was cancelled, as you may remember, on grounds of 'vulnerability']. A Wing Commander was given the job of trying to work out what the Russians would have to spend defending their cities. As far as I recall, the figure came to something like £4,000 million - at 1960s prices!

Well, said its supporters, that looks okay to us. Its detractors took the opposite tack - oh no, it can be defended against, the Russians could do it, and so the missile is useless.

Of course, a missile that cost the UK £100 million to develop, and which cost the USSR £4,000 million to defend against, might regarded as something of a success.
If one was prone to conspiracy, which I am not, it might be suggested that the entire OR.1182 effort was designed to justify Skybolt. However the entire affair seems somewhat strange and does remind me of recent efforts to play with various design studies and small research programmes whilst making allusion to grandiose but wholly impractical and really non-existent considerations in support of extracting goodies from the special relationship- be it with one across the Atlantic or the one across the channel.

I still remain curious as to the grounds for which the RAE had a particular dislike for the Avro W.140 when, on paper at least, it seems to be the best of all the designs offered over the various UK only stand-off deterrent missiles?
SLL: Schemes: No dis intended: "fan" simply to note the potholed path from doodle to delivery. Sometime luck, + or -, prevails: UK Cabinet Approval to spend (ultimately £1Bn - in the 1970s!) on (to be) Concorde: 29/11/62: Mac used it as debenture into the Roman Club: UK “ought to ‘cater for this profitable modern eccentricity’. He thought (Cabinet) really agreed. No one seriously dissented. It was all over in a few minutes.” J.Bruce-Gardyne/N.Lawson (future Chancellor!), The Power Game, Macmillan, 76, P28. No Minister gave a thought to investment return. “a good example of how a Govt. can find itself supporting a glamorous scientific breakthrough which does not make commercial sense.” D.Healey,The Time of my Life,Penguin,1990, P328. Sir A.Russell,designer (to be Chairman,Filton Div,BAC)A Span of Wings, Airlife,92,P.178: “In one respect Concorde bore straight comparison to (T.167 Brabazon) - no questions from anywhere had been asked on comparative airline operating costs." Do I hear the space/GW lobby wailing: if them, why not us?

CNH: Polaris: Spectacularly successful, so much so as to exacerbate UK Ministers' disillusion with UK GW: compare and contrast: USN's program: UGM-27 Polaris A1 SLBM, ITP 11/4/56, at sea 15/11/60. vs. well let's put Seaslug aside and take Blue Steel: (1955 schemes: ITP 4/5/56; 3/63 cleared for Vulcan 2 as inert shroud; live, progressively through 1964, range deeply compromised from Requirement. The BAC(GW) SSBN programme was Chevaline: sailed Oct.’82: PM Heath had initiated it at a 1972 Project Study guess of £175Mn; ultimate cost: £1Bn.

(Off topic: CNH: Blue Streak: was the intended strength to be 60 or 64? Or both at different times?
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Concorde stands emblematic of problems that existed in the UK A&D industry, the very fact that the government was considering funding it in the first place is telling, let alone the fact they made the decision. And it was not the first time they did that, Imperial Airship company anyone? I dont see any point is expanding this discussion in this thread. However when I eventually retire from my current career (many many years away) it is my intention to return to academia and produce a post-mortem of the UK A&D industry.
Do I hear the space/GW lobby wailing: if them, why not us?

Yes, and the supersonic aircraft team at Avro too. For what is the Concorde but an enlargement and fulfillment (at least in the technical sense) of their Type 730 dream?

Drifting OTT briefly, I wonder what it would have cost to build a couple-dozen Concordes for the RAF, with the passenger cabin gutted on the production line for more fuel, military avionics including cameras, a couple of free-fall nukes, and the price-per-build coming down accordingly?
I wonder what it would have cost to build a couple-dozen Concordes for the RAF, with the passenger cabin gutted on the production line for more fuel, military avionics including cameras, a couple of free-fall nukes, and the price-per-build coming down accordingly?

But rather pointless. A supersonic aircraft flying at high altitude has very limited manoueverability. It lines up on the target a couple of hundred miles away then flies straight and level, making it a sitting duck for SAMs.
Now all these were nuclear armed, but does anyone know what the warhead weight would have been?

What a good question PMN1 and nice of you to start a thread on it, looking for answers in a matter of history. Posted on the right forum for such matters.

Shame your not getting an answer but instead see your threat hijacked.
Wish I could help, but I suspect your resouces on this are now better than mine.
RE.179 stated weight was 850lb (UK Skybolt warhead)
RO.106 stated weight was 500lb (common-user warhead)

CJGibson said:
RE.179 stated weight was 850lb (UK Skybolt warhead)
RO.106 stated weight was 500lb (common-user warhead)


Thanks for that....i never stops surprising (and worrying) me just how much nuclear warheads were reduced in size and weight.
What is likely to be more accurate and more survivable (after launch) - a Skybolt type ALBM or OR.1149/1182
Ballisitc missiles are more accurate since their time of flight is shorter. Errors accumulate during long flight.

Survivability also goes to the ballistic missile. Indeed, no one has convincingly stopped one yet.
I agree with Nick.

However, back in the early 60s there were great hopes for ABMs, with even tactical SAMs being spec'd with a limited ABM capability. You'd need to look at ballistic missile RV terminal velocities and radar cross-sections etc to work out their vulnerability, but throw out a few decoys... Tracking a low-level air-breather over land would be quite a task for the radar systems of the early 60s, so that would be in the air-breather's favour.

I think the Air Staff was covering themselves by examining ballistics like Skybolt and hi/lo airbreathers like OR.1159 and OR.1182. After all they were also investing in low-level strike in TSR.2, so thoughts must have turned to a low-level stand-off missile. OR.1182 was viewed as insurance after all.

I've never heard of one, and it isn't my field, but was there a Soviet equivalent of Skybolt?


There was the Krechet-R - it was a 10.7m, 24,400kg behemoth of an ALBM armed with 6 MIRVs and 7,500km range, CEP 600m designed in 1983-84 as a survivable counterstrike weapon, arming a customised Tu-160K with increased payload capacity.

overscan said:
There was the Krechet-R - it was a 10.7m, 24,400kg behemoth of an ALBM ,

The Soviets certainly had a thing for big missiles, in all applications, didn't they?
Hi Chris,

Avro started work on a stand off missile in 1950, what sort mass of bomb would they have considered? Would it have been a 7,000lb weapon, atomic bomb?

CJGibson said:
RE.179 stated weight was 850lb (UK Skybolt warhead)
RO.106 stated weight was 500lb (common-user warhead)

Avro W.144 Blue Steel Mk.2 wind tunnel model:


Blue Steel Enhancements: “few (contracts caused) such bitter feelings (as) even in ’56 (Avro puffed 1,000n.m. MoS’ view was that if they) could not perfect (100n.m.) how could they (do) 10xthat? (Weapons Research Divn, many ex-RAE staff; weak management structure (criticisms) recriminations (were) common parlance” H.Wynn,Official History, RAF Strategic Forces,HMSO,P202/4.
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CNH said:
Avro 730 carrying a Grand Slam under each wing...
Hm. What would it do to the aerodynamics?

Completely ruined them I should imagine. Does raise an interesting point about the Grand Slam 2 proposal though, at a weight of 32,000lbs the thing was huge and would surely have stretched even the evolved Vulcan designs/phases Avro were playing with from 1956 onwards?
Wind Tunnel Measurements at M = 2.47 of the Mutual Aerodynamic Interference between a Guided Bomb and its Boost Unit During the Seperation Phase

This is about the OR.1159 weapon, note:

OR 1159 requiring the long range development of Blue Steel was in fact cancelled after the completion of a large proportion of the experimental programme. The results were not therefore analysed to the extent of using them for dynamic response calculations. However, it is hoped that the published results of the aerodynamic forces may prove of general interest.
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