USS Agerholm, DD-826

[Abbeywood.]

The 'Agerholm' was a Gearing class destroyer which appeared on the active lists of the Navy, after the end of WW2.
She was built at the Bath Ironworks yard and launched on 30th March 1946.
but enough of the facts and figures.

On the 11th May 1962 she was the designated test ship to launch the first, (and only), nuclear Depth-charge, (sic), as part of Operation 'Dominic'
Most of the tests in the programme appear to have been air-dropped and the only one on the given date was a submarine test named 'Swordfish' which took place approx' 400 miles west of San Diego and which is described as 'a full-scale ASROC/w-44 ASW rocket proof test'.
This leads me to wonder if this was the test involving 'Agerholm', or if the weapon she tested was a modified coventional shaped depth-charge.
Also, bearing in mind the necessity of depth-charges to sink fair rapidly, to have any effect on the intended sub', what would have been the minimum safety range to avoid damage to a) the launcher, and b) the crew thereof.
As 'Agerholm' was active until 1978, there might just be some person, or persons who would have served in her in the '60's, who are not bound by any security screen, and who could develop this posting.

Many thanks to the Moderators for their best wishes.

[WGVSr]

Pete:
I seem to remember it being mated to an ASROC [antisubmarine rocket] body. No idea on the yield though. There is one fairly famous picture extant of the test and the blast is a good ways away from Agerholm.
Bill

[Don Boyer]

The early ASROC used what is commonly referred to as the "Tsetse primary" a fission warhead utilized in several weapons, including ASROC, as a stand-alone warhead with a maximum yield in this configuration of about 10 kilotons..smaller than the Hiroshima detonation. In the ASROC configuration the warhead was designated as the MK 44. The same warhead, somewhat modified, was used in the Mk 57 free-fall bomb which could also be used as a depth charge and as the primary in several thermonuclear weapons such as the MK 43. The warhead was one of several of the era capable of using yield-adjusting techniques which could greatly increase the yield of the weapon in other than its depth charge configuration.

Some sources state that Agerholm and the "test" submarine were about two miles from the detonation point. Hard to judge from the existing photograph, but I know from my days in the program that I would not want to hang about 2 miles away from the detonation point of an ASROC for too long once that intensely radioactive water cloud falls back into the sea. And the submarine, if that close, must have gotten a serious jolt.

The photos show the standard 8-cell "matchbox" launcher for the early ASROC as well as an ASROC shipping container and transport dolly from the missile cruiser Columbus and a dummy ASROC on display on the destroyer USS Joseph P. Kennedy, DD-850. The dummy has the MK 46 torpedo warhead, a non-nuclear weapon which became the primary warhead of ASROC in it's later configurations. ASROC is now used in a vertical launch configuration for all modern warships, with a greatly improved non-nuclear warhead package.

[WGVSr]

Rummaging through some reference material [Bob Sumrall's "Sumner-Gearing-Class Destroyers"] I find the ASROC had a range of about 10,000 yards and could utilize the Mk 44 or 46 torpedo as a warhead or an Mk 17 [nuclear/modified B57 bomb] depth charge. I agree with Don, even at max range, 6 miles is way too close for me to a detonating nuke.
Bill

[John Odom]

In those days the hazard of radioactive material/radiation was way underestimated.

[Don Boyer]

If TEPCO's any example, it's still being underestimated today!

Re the ASROC warhead package, the MK 17 depth charge carried the MK 44 warhead as was said, a variation of the B57 warhead type. And six miles seems far more reasonable to me than the two I posted -- not sure where I saw that number. Six I could live with.

[Abbeywood.]

Thanks for the Info'. chaps.
While on the subject, I recognise that there was a certain, - nay, considerable, - amount of ignorance in those early days of playing around with nuke devices, with regard to the safety of personel, etc.
Assuming a weapon was dropped in earnest, on a SSN, would not the detonation of the ASROC missile create a further chain reaction with the sub's reactor. In my own opinion, yes , but you experienced ex-salts may wish to differ.
Last evening I watched a National Geographic documentary 'The Worlds Biggest Bomb' about the Bravo test carried out at the Bikini Atoll, Marshall Islands, where a submerged device was initiated in the lagoon from an bunker on the opposite side, by a special crew. who were hermetically sealed in. The only problem on their part was that after the detonation they had no means of safe recovery as they were meant to leave the bunker and board a helicopter thus exposing themselve to the fall-out.
Also on the receiving end was the USS 'Curtiss',(AVB-4) which was approx 35miles away also the recipient of fall-out.
Interesting programme

[Don Boyer]

The test you refer to was a test of the early Teller-Ulam thermonuclear device using a dry lithium-deuterium secondary device. if I remember correctly, the yield was around 15 megatons, the largest US detonation, covered in Richard Rhodes "Dark Sun". The largest detonation ever was the Soviet test of a down-graded thermonuclear device that produced 58 megatons. A totally unnecessary test, of course. Just Soviet PR at its best. The largest US weapon was the old Mark 17, with an expected yield around 21 megatons. Never used, of course, and testing it wasn't necessary as its components had already been tested to death in other devices. Theoretically, a thermonuclear weapon has no top end, unlike a fission bomb, which tops out at about 500 kilotons max.

[WGVSr]

The Bravo shot was the last on Bikini. If you want to read more on the Bikini tests, try Johnathan Weisgall's "Operation Crossroads' [ISBN 1-55750-919-0]. The book's a little biased, Weisgall was the Bikinians' attorney through the '70s and '80s, but read critically the book is good commentary on the Bikini tests and has a chapter on the Mike and Bravo shots.
Bill

[Don Boyer]

Bill, I agree -- a somewhat biased but good book on the Bikini Atoll testing.

I've always found it interesting that there was so much angst over the US using the bombs in wartime at Hiroshima and Nagasaki, yet world governments blasted away for years "testing" weapons all over the place anyway, despite continued protests that so many were hardly necessary (and they weren't). The nuclear components of the various weapons, fission or fusion, were highly reliable. The testing was of the delivery systems and other components of the system, much of which could have been done with just the high explosive and a dummy "pit" since the functions of the actual nuclear components were highly reliable and unlikely to fail if all else operated according to plan.

Cold War saber rattling at its best. Mutually Assured Destruction would have been just that had it ever come down to it, as the Soviets finally figured out during the Cuban Missile Crisis. Now we have a world full of idiots who think possessing nuclear weapons will preserve their dysfunctional communist lifestyle or make Islam dominant in the courts of world opinion. Nuts.

Of course this comes from someone who spent years working on nuclear and thermonuclear weapons...

[ludsie]

Good point Don to use Nuclear weapons again would be a complete act of madness

[battlestar]

Originally Posted by ludsie

Good point Don to use Nuclear weapons again would be a complete act of madness

Too true, too true...

USS Agerholm (DD-826) was the last of her class to visit Australia (Fremantle) in 1978 (Image). I have the 'Welcome Aboard' booklet for her somewhere...

Battlestar

[Don Boyer]

Was just cruising through this post once again, and noticed Abbeywood's question regarding a nuclear detonation involving the target submarine's nuclear reactor as part of the chain reaction. This is not possible, even with a direct hit. An A-bomb detonation does all its work inside a millionth of a second or so, then all the energy exchange is a done deal. All the active material involved in the reaction has to be a part of the weapon "pit" -- anything else is too far away to be involved in initial chain reaction in any significant yield-boosting manner. All that might happen, assuming the detonation was close enough to vaporize the casing of the nuclear reactor, would be to add some more nasty radioactive molecules to the mix, which would not significantly increase the "yield" of the weapon in any way -- it would just add to the poisonous fallout laying about, which is plenty bad enough in it's own right.

[Abbeywood.]

Greetings, Don,
Just noticed your response to my query, (see post #7), which pretty much answers the question regarding 'nuke' detonations in close proximity to SSN's. For that, I thank you.
Your mention of the Russian super-bomb seems to have coincided with a showing on a UK TV channel, of a documentary about that particular device, apparently named the 'Tsar',
Having disposed of the last Tsar, Tsarina and family in 1917 one can only presumed they intended to re-incarnate them to dispose of the rest of us.
All the Best,(ATB), Pete'