USA ASAT merging Sparrow and Polaris

[Temistocle]

In the document below, at page 23 there is the following sentence:

"During the early 1960s, the U.S. Navy was also researching possible ASAT capabilities. Early efforts focused on matching a Navy Sparrow anti-aircraft missile with a Polaris Submarine-Launched Ballistic Missile (SLBM) but these efforts did not proceed beyond ground experiments."

Any other info/drawing/picture will be very appreciated.

PS: Another version of the same document is available online at The Space Review website, in a three-part paper starting here.

 

[Deleted member 2278]

There is frustratingly little to be found on this but it was studied under "Early Spring". Page 114 of the book in the link below mentions Raytheon modifying a Sparrow with an infra-red seeker to detect the reflected sunlight from satellites. (It requires you to log in to view the book but if you scroll down on the search inside results, relevant excerpts can be read without logging in).

The militarization of space : U.S. policy, 1945-1984 : Stares, Paul B : Free Download, Borrow, and Streaming : Internet Archive

334 pages ; 25 cm

archive.org

 

[NMaude]

"During the early 1960s, the U.S. Navy was also researching possible ASAT capabilities. Early efforts focused on matching a Navy Sparrow anti-aircraft missile with a Polaris Submarine-Launched Ballistic Missile (SLBM) but these efforts did not proceed beyond ground experiments."

Given that the AIM-7 Sparrow used SARH guidance I'd love to know what this proposed ASAT's terminal mode of guidance was?

 

[Dilandu]

There is frustratingly little to be found on this but it was studied under "Early Spring". Page 114 of the book in the link below mentions Raytheon modifying a Sparrow with an infra-red seeker to detect the reflected sunlight from satellites. (It requires you to log in to view the book but if you scroll down on the search inside results, relevant excerpts can be read without logging in).

Er... how exactly they planned to use Sparrow in vacuum? This missile is guided by aerodynamic control surfaces.

 

[Dilandu]

 

[TomS]

Probably better not to visualize a complete Sparrow missile with fins sitting on top of the Polaris. They were likely using Sparrow essentially as a chassis -- recycle the warhead and fuze, the rocket motor, and maybe some guidance electronics. So, possibly the new IR seeker was set up to provide similar types of outputs as the Sparrow SARH seeker (basically, a pointer toward the direction of strongest return). The existing guidance circuit would see that output and try to drive the missile to center that strong return in the seeker FOV (Sparrow's early logic was a pretty crude). The outputs from that circuit that would normally drive fin control motors would instead drive some other steering mechanism (perhaps solenoid valves connected to a gas generator).

 

[Dilandu]

The outputs from that circuit that would normally drive fin control motors would instead drive some other steering mechanism (perhaps solenoid valves connected to a gas generator).

Problem is, that dynamic of rocket in space is quite different from the dynamic of rocket in atmosphere. Franky, I suspect that this project may be the case of engineers understanding too little about such new matter as space, and assuming that "it would be simple!".

 

[Deleted member 2278]

As @TomS points out, I don't think we are talking just sticking any given AIM-7E on top of a Polaris here but a Sparrow derivative in a relatively elastic sense.

It is difficult to track this project as it was canned, ostensibly to protect Polaris stocks in the early-60s but was looked into again late-60s/early-70s depending on where you read. The details though are vague to say the least! The concept was at one point based on Polaris/Sparrow but not necessarily so throughout the Early Spring programme.

As I understand it, having read multiple, slightly differing descriptions, the plan was to have the Polaris launch the Sparrow-stage into the target's path, which would proceed to "hover" for up to 90 seconds (motor burn out time?) and prosecute the target with a fairly conventional proximity warhead. The appeal of the project was that the entire launch complex, whether ship or sub (the latter needing off-board targetting obviously) could travel to the target's orbit, something Vandenburg couldn't do!

Why didn't it happen? Well first off, we are working with decades-old layperson descriptions which are necessarily simplistic. So I think claiming LTV and Raytheon understood too little is unfounded at best. From what I can gather, the chief concern was the afore-mentioned Polaris stocks but I also read that the ability to conduct on-orbit inspection was a concern. This ultimately led the USAF toward Blue Gemini as I understand it.

In the link above, it is mentioned that Raytheon were refused permission to pursue a camera in the Sparrow nose but I think that this is somewhat lacking in detail. It is likely that relaying a TV signal back to the surface for a remote visual inspection and giving the Sparrow a man-in-the-loop capability was either not technically feasible (less than 90 seconds is tight timing to be certain), prohibitively expensive or both. Between that and the USAF lobbying for dominion is I think why it was ultimately not proceeded with.

Earlier, the USN looked at various other ASAT projects such as NOTS, Caleb, Hi-Ho(e) and a project called Skipper which apparently investigated a Scout-launched "buckshot" or pellet warhead (the trouble with searching for navy and skipper is obvious!). The USN was obviously quite invested in ASAT in the 1960s. If a would-be author could reach better sources, it would certainly be worthy of a book!

 

[Archibald]

I readily second the above opinion. Between Polaris Scout Sparrow and NOTSnik and Early Spring (think that was the name) the Navy ABM projects are fascinating.
Also seaborne ABMIS later - and its 30 000 tons floating SAFEGUARD DEFENDER missile cruisers.

US Presidents and the Militarization of Space, 1946-1967

In the clash of ideologies represented by the Cold War, even the heavens were not immune to militarization. Satellites and space programs became critical elements among the national security objectives of both the United States and the Soviet Union.According to US Presidents and the...

books.google.fr

 

[TomS]

The outputs from that circuit that would normally drive fin control motors would instead drive some other steering mechanism (perhaps solenoid valves connected to a gas generator).

Problem is, that dynamic of rocket in space is quite different from the dynamic of rocket in atmosphere. Franky, I suspect that this project may be the case of engineers understanding too little about such new matter as space, and assuming that "it would be simple!".

Oh, it's no doubt a very simplistic solution that would have run into quite a few problems of execution. But as a starting point, it's not conceptually absurd.

Remember that the early Sparrow seeker is really simple. Its scans the antenna around the field of regard and sends very basic steering commands to try to center the strongest return in the seeker's FOR. This basic logic that works with a radar antenna and fins also works for an IR camera and thrusters; you "just" have to tweak the rates and so forth.

 

[NMaude]

Remember that the early Sparrow seeker is really simple.

It used a conical-scan seeker introduced in the AIM-7C.

 

[Dilandu]

As far as I could imagine the whole concept, the idea basically was:

* Launch "Polaris" nearly vertically on trajectory, crossing the satellite orbit
* Calculate the upper stage burning in such way, that the missile would reach satellite orbit altitude with almost zero vertical velocity, and hover, compensating the gravity drag with engine burning.
* Essentially, the missile became statite - the spacecraft, staying over the planet not by orbital velocity, but by compensating the gravity with engine power.
* When the satellite come nearby, the infrared detector of (heavily) modified "Sparrow" missile would detect it.
* The "Sparrow" would shot toward satellite, hitting it with (presumably) shrapnel warhead.

Essentially, the whole concept is statite orbital mine.

Disadvantages is kinda obvious; the launch platform must be exactly under satellite orbital path. Advantages, presumably, is much simpler intercept calculation; the missile is launched vertically and basically could be considered static, and only satellite's own movement are taken into account.

 

[Deleted member 2278]

Not quite how I've read it. The Polaris gets the Sparrow into the target's orbital path and the Sparrow holds position for up to 90 seconds. It needn't be that long if timed correctly (assuming IFF was a non-issue - which turned out to not be the case). The Sparrow doesn't have to "shoot" anywhere. The target is coming to it. Fast. There is some mention of work on a re-startable motor to achieve the "hover" but no specifics.

The launch platform being under the target is no disadvantage. It's a feature. As this system would be ship/sub-based, it offers up enormous flexibility. All satellites have to pass over water at some point. It would be a good use of an otherwise obsolete CA or CVL. With suitably armed "41 for Freedom" class boats, a great deal of a satellite's orbit could be held under threat. You would never know if that tracking vessel had a shooter with her.



The station is great from 128.....

 

[Archibald]

He he... there were scores of small, antiquated and cramped "jeep carriers" in storage since WWII, perhaps 120 of them. 19 kt and 10 000 tons average.

Of the 151 aircraft carriers built in the U.S. during World War II, 122 were escort carriers

Very bad for any jet, but Polaris SLBM of course don't care at all.

Category:World War II aircraft carriers of the United States - Wikipedia

en.wikipedia.org

List of escort carriers of the United States Navy - Wikipedia

en.wikipedia.org

Light aircraft carrier - Wikipedia

en.wikipedia.org

Such discussions of "Polaris on ships and old hulls" reminds me of plans for NATO MLF - Multi-Lateral Force. Best example: that rebuild italian cruiser that got Polaris launch tubes but never used them. Also USS Long Beach (AFAIK) was to have Polaris tubes.

Of course a "must have" would be "more 41 for Freedom" submarines - but they surely cost an arm and a leg each, not sure Congress wouldn't balk at the cost even after 1967 when the last of the "41" launched from its shipyard.

The Air Force obviously would go crazy over such plans.

Now that's a pretty fascinating tech-wank whatif, for sure. Must integrate it in "Dark Moon rising".

I can see the Air Force countering "Early spring", its ships and submarines and Polaris suborbital system - with a mix of B-52s / Minuteman boosters / Agenas in the SAINT mission, orbital.

 

[Archibald]

Good summary here

Early Spring

 

[Dilandu]

Not quite how I've read it. The Polaris gets the Sparrow into the target's orbital path and the Sparrow holds position for up to 90 seconds. It needn't be that long if timed correctly (assuming IFF was a non-issue - which turned out to not be the case). The Sparrow doesn't have to "shoot" anywhere. The target is coming to it. Fast. There is some mention of work on a re-startable motor to achieve the "hover" but no specifics.

One problem: how exactly Sparrow, with its 8-sec burning motor, could hover up to 90 seconds? It is not on orbit; it's just hovering vertically. Which means, that it require far more capable motor. Also, the text you give:

Theoretically, a missile submarine parked itself under the path of the target satellite. The crew launched a missile that had a booster with just enough power to attain the desired altitude. Attached to a restartable upper stage, the payload would hover at the target altitude for up to 90 seconds waiting for the satellite to arrive. An optical scanning system, sensitive enough to see an object that the unaided eye would strain to see, first located the target with a wide field of view and then, once it had identified the target, tracked it with a narrow field for precise guidance.

The missile relayed data to the submarine for real-time control. Once it had identified the target, the vehicle maneuvered onto a collision course, and a proximity fuse detonated the warhead releasing thousands of steel pellets. The impact of even one pellet would destroy the satellite. A submarine could launch several missiles at one target. A major advantage of Early Spring was that the Polaris submarines could go almost anywhere to get at a satellite.

Correspond much more with the idea of "Sparrow" missile being shot from "restartable upper stage" toward the target. Because otherwise, it's not clear why we need "Sparrow" at all; if "restartable upper stage" done all the maneuvering, there is zero gain from using anything from "Sparrow" at all.

No, I'm still under opinion, that the idea was to shoot "Sparrow" from the "restartable upper stage" toward enemy satellite.

P.S. The whole project, frankly, looks ridiculously overcomplicated. It required not only optical homing, but also command guidance from submarine via datalink.

 

[Deleted member 2278]

Early Spring

^ Interesting link. In line with much of what I've gleaned. I have my doubts about the real-time control claim though. The interceptor would be in something of a low-energy state so any decision would need to be prompt, very prompt. Control would probably be limited to go/no-go as I don't believe any implied fully manual control would be practical or even particularly desirable. I also have doubts that a submarine would linger and what is more, broadcast to the interceptor. Any submariner worth their dolphins is going to want to go deep after launch in anything other than very benign waters, surely?

It also paints the picture of the Sparrow shooting off after the target upon acquisition. That 90 seconds limit seems awfully definitive though. If it had "shooting off" fuel to spare to instead hover for longer, then why wouldn't that be an option? If the Sparrow is thrusting just to maintain co-altitude with the target, I can't really envisage it haring off after the target, unless it acquired very early in the engagement and had fuel to spare. I see an engagement as essentially the target walking into a long, puffing, IR-detonated proximity mine.

@Dilandu you seem wedded to the idea that this Sparrow is anything like a stock AIM-7/RIM-7. Perhaps instead think of it as a Raytheon-designed bespoke interceptor stage using the Sparrow designator as an oft-used budgetary cheat. As I said, it was intended to utilize a restartable motor of unknown characteristics but the word "hover" turns up in most (all?) descriptions and the 90 seconds in more than one. This strongly implies to me something thrusting against gravity to hold relative station, presumably in puffs/pulses etc. before fuel exhaustion and the inevitable falling-off of altitude. Early Spring is afterall described as a low-energy interception method.

Now, with sources being multitudinous one-liners and odd paragraphs in various documents, it is hard to be definitive, particularly as it is not a monolithic project but studies investigated more than once perhaps with details conflated over time. You have a very different interpretation (and value judgement) which you are perfectly welcome to. My interpretation is merely that, though equally valid.

The project though is fascinating and very worthy of discussion/inclusion!

 

[Dilandu]

It also paints the picture of the Sparrow shooting off after the target upon acquisition. That 90 seconds limit seems awfully definitive though. If it had "shooting off" fuel to spare to instead hover for longer, then why wouldn't that be an option? If the Sparrow is thrusting just to maintain co-altitude with the target, I can't really envisage it haring off after the target, unless it acquired very early in the engagement and had fuel to spare. I see an engagement as essentially the target walking into a long, puffing, IR-detonated proximity mine.

Not exactly. It would require the statite mine to be perfectly placed (with the margin of error of several dozen meters) on satellite orbit. It isn't easy, and 1960s technology hardly could do it. Not to mention, that such "mine" could be avoided by very small trajectory change on the side of sattelite.

The idea of interceptor missile being fired FROM the statite mine is seemingly more practical. It allows to compensate for imperfect positioning of statite, and small, high-performance missile with maneuvering system is just easier to guide into target, than massive statite itself.

This strongly implies to me something thrusting against gravity to hold relative station, presumably in puffs/pulses etc.

Essentially yes, as I mentioned - it's a statite. The spacecraft that stays in space not by orbiting the body, but by working engines against the gravity.

@Dilandu you seem wedded to the idea that this Sparrow is anything like a stock AIM-7/RIM-7. Perhaps instead think of it as a Raytheon-designed bespoke interceptor stage using the Sparrow designator as an oft-used budgetary cheat.

Well, there is a possibility that mentioning "Sparrow" was basically an advertising trick) I.e. to get Congress approval, they pretended that it's a "cheap" project - "just a combination of already existing missiles, with small modification".