Calling all Allen M. Sumner-class & Gearing-class DD fans

[Rick E Davis]

The MK 57 was intended to be a "poor man's" Mk 37 that could control both 5-in and the medium AA guns aboard a ship. The USN realized that there were times they wanted or rather needed to, shoot at multiple targets and if the main Fire Control director was disabled ... they were well ... screwed. The only destroyers I'm aware of to get it were post-war once 3-in mounts were installed (except for some experimental installations with 40-mm mounts).

Sorry: I was thinking of the Mk 56 GFCS used on destroyers for the 3-in mounts.

The Mk 63 was actually a "quick-fix" to replace the failed Mk 49 director. The USN wanted to use the radar from that system on "something" that would fill the "blind-fire" role. The biggest failing of the Mk 49 director, was it couldn't rotate fast enough to track faster aircraft. The simple man operated Mk 51 director could be rotated fast enough to do the job. By mounting the radar on the gun mount, the tracking was as good as what the mount could do. Think about it, the Mk 49 was cancelled in October 1943 and a replacement was available in December 1944. Amazing. I have been told by someone who used the Mk 63 GFCS when he was in the USN in the 1950's, that it didn't work all that well.

[whaynes]

Rick, are there any available diagrams or additional photos of Gearings in Measure 33a Design 28D? That's an interesting design, even if only used during trials.

Couldn't find anything at the usual sites other than the photos above.
Walt Haynes

[Rick E Davis]

The best photos of these destroyers with the dazzle camo are the ones of FRANK KNOX (DD-742) prior to her conversion to a Radar Picket while running trials off Rockland.

If you have a specific area of the ship that you wish to see close-up ... I can do some close-up views. Let me know here. I won't be able to post today, I have a commitment with my son.

[Guest]

Rick,
I'd appreciate seeing any shots of Frank Knox after her conversion to DDR and in Measure 21. Do any show if she lost the third dual 20mm in the fantail gun mount?
Thanks for any that you can show.
Best regards,
Rick T.

[whaynes]

Rick, any pictures of Frank Knox in Measure 33a Design 28D would be appreciated. No hurry.
Walt

[Rick E Davis]

Walt,

Did you look on the previous page? I posted two photos of FRANK KNOX and two of SOUTHERLAND in the dazzle camo they had when commissioned. Those are the best sharp clear images I have of these destroyers with the dazzle camo. I don't know about available camo diagrams for this scheme.

Rick T.,

I posted one image of FRANK KNOX after her conversion to a DDR in Ms 21 on the pervious page. ALL of the DDR's had a reduced 20-mm armament (total of eight twin 20-mm mounts instead of ten) with only two twin Mk 24 20-mm mounts on the fantail. This was done to compensate for the added weight from the DDR conversion. It is kind of interesting that all the fantail 20-mm armament was removed from the fantails of DDR's in 1946.

I don't have any good overhead views of FRANK KNOX as a DDR during WWII, I do have a few overhead views of SOUTHERLAND after her conversion. If interested in those images, I can try posting. I suspect the quality of detail will be poor ... because they are dark images.

[Rick E Davis]

The ONLY GEARINGS to go OPERATIONAL with the aft TT mount in place were DD(R)-742 FRANK KNOX and DD(R)-743 SOUTHERLAND. Several others completed their Radar Picket conversions with the aft TT mount in place, but it was soon replaced with a quad 40-mm mount.

DD(R)-742 FRANK KNOX on 13 July 1945 ... likely it can't be seen in this view very well, but the aft TT Mount was still in place.


DD(R)-743 SOUTHERLAND on 3 April 1945


DD(R)-805 CHEVALIER on 24 May 1945

[whaynes]

Rick, were there any differences between USS Frank Knox and USS Chevalier?
Walt

[Rick E Davis]

Walt,

Yes and No. It depends on when. When the Radar Picket conversion was "initially" done at Boston Navy Yard for the Bath Iron Works built GEARINGS (the Orange Tx built units were converted to DDR's at Norfolk Navy Yard), they were more or less all common in configuration. But, as with any new ship "type" there were modifications made in an iterative process until the configuration was deemed "good". Also, I have noticed quite confusing changes to arrangement to the DBM antenna locations in 1945 and after the war. They started on the tripod, then one antenna was moved to the front of the foremast. Then on some ships it was moved back ... go figure. In 1946 it appears most units were standardized except for some antenna location moves. I have noticed some differences in the bulwark ("tub") around the added quad 40-mm depending on which yard installed it.

DDR-742 (arrived in the Philippines on 16 June 1945) and 743 (departed East Coast on 24 April 1945) went to the Pacific with the aft TT mount (they got the third quad 40-mm mount in 1946), all other DDR's (DDR-805 left GITMO on 18 June 1945 for the Pacific and DDR-806 left the East Coast for the Pacific on 24 May 1945 ... I think HIGBEE was updated to the Anti-Kamikaze Mod at Norfolk prior to leaving) went to the Pacific with the Anti-Kamikaze Mod replacing the TT mount with a quad 40-mm mount. Camo appears to have been Ms 21 for DDR-742 and 743 when they went to the Pacific. Most others (if not all others) were in Ms 22 (DD-805 was in Ms 22).

[Roger Torgeson]

Did the USS Chevalier DD-805 still retain her 40mm in 1954 or had they been replaced by the newer 3� /50 cal mounts by then. I can�t tell from the photo on NavSource.

[Rick E Davis]

Roger,

CHEVALIER (DD-805) was updated with 3-in RFG Mounts at Mare Island Navy Yard between 1 October 1954 to 14 March 1955 according the records I have found at NARA (at least those were the scheduled dates and the photos show that she did receive the Mod, but the actual dates could be off a few days or weeks). I have no photos of her in the 1950's. CHEVALIER was one of the last four DDR's updated with 3-in RFG in FY55.

All of the DDR's received 3-in RFG mounts. About six DDR's had the RFG installed in a configuration similar to the first GEARING/SUMNER Fleet Destroyers updated with 3-in RFG's of two twin mounts and two single mounts. (The installation of the twin 3-in mounts on GEARING/SUMNER Fleet Destroyers was changed to an in-line arrangement) The rest of the DDR's (including CHEVALIER) had a different configuration with three twin mounts (no single mounts) similar to the layout used on FLETCHERS (two between the stacks and one superimposed over 53 mount). A few Fleet Destroyer GEARINGS and most DDE GEARINGS didn't get 3-in RFG upgrades prior to FRAM.

[Guest]

http://www.tehnoart.eu/18/med/G1_.htm
Model GEARING class!

[falcon04]

Modified SP antenna as fitted to GEARING class radar pickets in WWII.

Try as I may, I can't find clear pictures or drawings of this antenna. Any out there ??

[Russ2146]

http://www.modelshipgallery.com/gallery ... index.html

There's one on WEM's WW2 US Radar fret and another on ther Essex carrier fret http://www.modelwarships.com/reviews/pe ... sex-01.jpg

But you'reright, there's nothing out there with a clear ID except this

SP Antenna.jpg (42.33 KiB) Viewed 3542 times

805 CHEVALIER PORT BOW APRIL 1945 (2).jpg (80.44 KiB) Viewed 3541 times

Don't ask me where I found it, I don't know. It was in one of my photo folders, so I must have come across it in the last two years.

[falcon04]

Thanks, Russ - but, that's the original SP - the modified antenna is "cropped" top and bottom and has a different "multiple" feed horn array - it actually looks like a completely different antenna. I'll find the best I have and edit this post.

1st edit:

I see your edit - that's the one. It appears that the long feed horn has been changed - I assume that this includes the IFF array on the antenna. some of the prior DDR photo's posted show "fuzzy's" of this antenna.

Here's the HNSA page on the SP - mentioned is the "8 foot cut parabola with provision for the BO antenna"

http://www.hnsa.org/doc/ecat/cat-1029.htm

BL , BM, and BO were IFF transponders, but HNSA doesn't illustrate.

2nd edit - the next HNSA page covers a mobile ground version of the SP - which has a better shot of the 8' cropped antenna:

http://www.hnsa.org/doc/ecat/cat-1030.htm

[Cliffy B]

Guys, correct me if I'm wrong but aren't the second and third photos you posted Russ of an SM instead of an SP? Is that the radar your trying to figure out Falcon?

Here's a shot on an SM on BB-46 for comparison.
http://www.navsource.org/archives/01/014643.jpg

[Russ2146]

The photos I posted are from DDRs so if they carried SM on the aft tripod, maybe so

[Rick E Davis]

SP antennas/radars were suppose to be a smaller version of the SM and were simpler and more reliable. There were "full-size" and smaller SP antennas. I think the first photo is a SM radar antenna, the other photos are SP-1 radar antennas. And actually there were two versions of the SM radar ... SM an earlier large version (96-in dia.) used on some Carriers (23 sets built), and a smaller lighter weight version ... SM-1 (72-in dia.) ... that replaced the earlier SM sets.

The SP radars on the DDR's are clipped at the top and bottom and a BO IFF antenna is mounted around the front if I understand Friedman's description.

Source: Friedman's NAVAL RADAR book, 1981

[falcon04]

SP versus SM

Well, the HNSA page

http://www.hnsa.org/doc/ecat/cat-1029.htm

has the "first" photo heading the pages for the SP, but the last pic is the later cropped version used on the GEARING-class pickets - and the one represented in the CHEVALIER kit.

We'll get there - just a bit confusing !

[Alan Raven]

The key will be the AS number.
AS stands for 'antenna asembly'.
Not too long after the war, antennas were given antenna assembly numbers. These numbers are distinct from the radar type designations such as SP at al. A set may have more than one antenna associated with it. The SPS8 series is a good example of this.
Friedman does not give antenna assembly numbers in his Naval Radar volume.
The US Navy produced, and probably still does, detailed drawings to very large scale of the antenna assembles, and I have a few of these.
A new line of research for all of you neophytes. I hope this is of some use, and good luck.

SP antennas/radars were suppose to be a smaller version of the SM and were simpler and more reliable. There were "full-size" and smaller SP antennas. I think the first photo is a SM radar antenna, the other photos are SP-1 radar antennas. And actually there were two versions of the SM radar ... SM an earlier large version (96-in dia.) used on some Carriers (23 sets built), and a smaller lighter weight version ... SM-1 (72-in dia.) ... that replaced the earlier SM sets.

The SP radars on the DDR's are clipped at the top and bottom and a BO IFF antenna is mounted around the front if I understand Friedman's description.

Source: Friedman's NAVAL RADAR book, 1981