Cadillac Radar IFF (Was CASF Essex)

ar · Post by ar » Sun Oct 28, 2007 5:31 am

Can anyone tell me what ships of the class were fitted with Cadillac equipment. I ask as this affects the late war rig configeration and airgroup make-up.

ar · Post by ar » Sun Oct 28, 2007 7:28 am

ar wrote:Can anyone tell me what ships of the class were fitted with Cadillac equipment. I ask as this affects the late war rig configeration and airgroup make-up.

Re my above note, I have noted from photos that Hancock, Randolph and the Ticonderoga were so fitted. Were there any other ships of the class with the equipment?

ar · Post by ar » Sun Oct 28, 2007 2:04 pm

Cadillac: Name given to an early airborne warning system ; came into service in late 1944. Exact date unknown to me.
Radar (type APS 20) I think, without looking it up, fitted to Avenger type aircraft in a large dome under the fusalage.
Data transmitted in real time to specially equipped ships (Essex class and possibly others) to allow direction of fighters onto enemy aircraft.at long ranges.
Ships so fitted with this receiving gear had a LARGE omnidirectional antenna fitted high up on the port side of the stack on a special platform.
The antenna looked like a candlestick tapered towards the top.
I do not know the antenna designation, but on official plans it is listed as Cadillac.
Look for it in the three ships that I listed.
Get back to me.

Post by **Timmy C** » Sun Oct 28, 2007 2:10 pm

Guessing that's the thing I've circled in red here?

ar · Post by ar » Sun Oct 28, 2007 2:18 pm

Correct.

Post by **Timmy C** » Sun Oct 28, 2007 2:23 pm

Here's one of the Hornet in January 1944:

Although I guess that might not be the same antenna, since it's a bit taller than the earlier one I posted.

Tracy White · Post by **Tracy White** » Mon Oct 29, 2007 12:25 am

I don't think Cadillac shipped on any Essex carriers, and the antennae in question has been described as a homing beacon of sorts in some texts I have read. This Wikipedia entry would suggest that Cadillac I didn't arrive until August 1945 aboard CV-4 Ranger. Any sources you can give me that would say otherwise?

ar · Post by ar » Mon Oct 29, 2007 8:54 am

Tracy White wrote:I suspect that photo is misdated but I can't offer anything to correct it so I've kept my mouth shut.

WR: I don't think Cadillac shipped on any Essex carriers, and the antennae in question has been described as a homing beacon of sorts in some texts I have read. This Wikipedia entry would suggest that Cadillac I didn't arrive until August 1945 aboard CV-4 Ranger. Any sources you can give me that would say otherwise?

A beacon you say? Are you certain that you wish to stick to that story?
I am not trying to trip you up here. A beacon... think about it. Beacons to be really effective had to be directional, did they not? At least on ships.

You reference Wikipedia. No swear words please. You really should know better.

Tracy White · Post by **Tracy White** » Mon Oct 29, 2007 11:02 pm

Those asking for help should be a little less tetchy. Wikipedia apparently knew more than you, and there are ten sources cited on the page I linked to.

The antenna in question is a BL IFF.

Folks, RADAR OPERATORS' MANUAL, RADAR BULLETIN NO. 3, (RADTHREE), April 1945 - page 2-3.

DE-220 Antennas page (bottom photo)

early AEW Aircraft. They've got something on Cadillac for you as well.

ar · Post by ar » Wed Oct 31, 2007 8:37 am

Tracy White wrote:Those asking for help should be a little less tetchy. Wikipedia apparently knew more than you, and there are ten sources cited on the page I linked to.

The antenna in question is a BL IFF.

Folks, RADAR OPERATORS' MANUAL, RADAR BULLETIN NO. 3, (RADTHREE), April 1945 - page 2-3.

DE-220 Antennas page (bottom photo)

early AEW Aircraft. They've got something on Cadillac for you as well.

Dear Mr White,
Thank you for posting the data links. which I read and found interesting.
I am familar with the Mk 111 IFF system and the antennas that go with it in respect of ship fits.
I have some calls out to people on the matter of using the large Combined IFF antenna as the Cadillac receiving antenna, in terms of confirmation of what is on the official plans. With any luck somebody will get back to me in the not too distant future. Until then I cannot prove my case in this matter. But there HAS to be a dedicated receivng antenna for the system, would you not agree?

Re the entry on antenna systems that you linked. Whatever idiot compiled this should be taken out and shot. Is there no peer review for entries, or can anybody put anything in?

To give just three errors;

" Radar was a British invention". Give me a break.

A photo of USS England showing what is stated to be a radar jammer, not true, what is shown is in fact an SQ radar set.

An FC radar is listed as being an XAF AIR SEARCH radar. The compiler must have been drinking.

These are Three MAJOR errors that I found in just a quick look.

Cadillac; One gets a much better description from Friedman in Naval Radar and US Naval Weapons Systems.

On being tetchy; only when the market goes down. However my postings are quite often brusque, a fault of mine.

Look forward to hearing from you.

Tracy White · Post by **Tracy White** » Wed Oct 31, 2007 11:45 am

There is a lot of confusion and contradictory information out there in regards to radar, as you well know. I haven't been able to purchase Friedman's radar book as of yet, but it is on my radar, so to speak.

Speaking of Wikipedia, this may be of interest.

ar · Post by ar » Thu Nov 01, 2007 12:28 pm

Tracy White wrote:There is a lot of confusion and contradictory information out there in regards to radar, as you well know. I haven't been able to purchase Friedman's radar book as of yet, but it is on my radar, so to speak.

Speaking of Wikipedia, this may be of interest.

I have spoken to Norman Friedman who related the following on Cadillac.

The Cadillac equipted aircraft has to identify the Cadillac equipted ship before sending the data, this in order to ensure that the correct vessel is being targeted for the data.
Identification of the correct ship is achieved by sending a special interrogator code to the ship so fitted with Cadillac. Upon receipt of the correct response from the carrier, the aircraft then will send the radar data to the ship. The data is received by the lower part of the antenna.
Therefore, one part of the antenna on the ship functions as a transponder, while the other part receives the data which is displayed on a repeater screen in the CIC. THis allows direction of friendly fighters onto low flying enemy aircraft, which would otherwise not be detected until much closer to the Fleet.
He tells me that Cadillac at the time of introduction was top secret and did not appear in manuals marked only as "confidential".
I mentioned the labelling of the antenna on the Randolph as being Cadillac, his response was, "that is definative".

PS note that the BL IFF (stovepipe type) antenna shown in the confidential manual is different to that fitted on the Radolph.

Let me hear from you.

Tracy White · Post by **Tracy White** » Thu Nov 01, 2007 5:16 pm

Alan, I noted in some of the text that I came across a claim that early radars (such as the SC) had the BL separate, but that the SC-2 had it integrated. At that point, there was so much contradictory info that I just made a note as something to look into, but that does jibe a bit with what you've posted. One of the sites I found that on was NHC's "Shipborne Search Sets". Note the SC section, "SC-2 and SC-3 also have PPI scopes, remote PPI's, and built-in BL and BI* antennas."

Werner may be re-adding a question here I accidentally lost, but since we may be requesting that you bug Mr. Friedman, I would ask if he has any recollection of the approximate time the Essex class received the antennaes as the documents for the aircraft and system in general I've found don't seem to match the shipboard sets.

Werner · Post by **Werner** » Thu Nov 01, 2007 5:19 pm

Mr. WR is referring to the Cadillac data link antenna, which receives essentially a TV image of the airborne APS 20's Radar image for a repeater console aboard ship.

It was not a sensor, or even a critical part of the system, but it was an important one, and it's antenna would feature on many ships in the 1945-55 timeframe which corresponds to the APS 20 system.

If anyone is still curious, I will go through my copy of Shipboard Antennas for particulars on size, shape and placement.

ar · Post by ar » Thu Nov 01, 2007 5:52 pm

If you would please.
Additionally, could one of the aircraft persons look at a good book on the Avenger to see what there might be on the system, when it came into use, and on what ships during the war.

Tracy White · Post by **Tracy White** » Thu Nov 01, 2007 5:55 pm

I'd be interested... one more detail I can keep my eyes open for...

ar · Post by ar » Thu Nov 01, 2007 6:08 pm

Tracy White wrote:Alan, I noted in some of the text that I came across a claim that early radars (such as the SC) had the BL separate, but that the SC-2 had it integrated. At that point, there was so much contradictory info that I just made a note as something to look into, but that does jibe a bit with what you've posted. One of the sites I found that on was NHC's "Shipborne Search Sets". Note the SC section, "SC-2 and SC-3 also have PPI scopes, remote PPI's, and built-in BL and BI* antennas."

The SC2-4 range had the IFF antennas hung on the face of the IFF reflector screen attached across the top of the large main radar antenna.
SC and SC1, I believe, had to have (when fitted) , the IFF antenna placed away from the reflector, probably due to the light construction of the SC framework.

Tracy White · Post by **Tracy White** » Thu Nov 01, 2007 7:00 pm

ar wrote:If you would please.
Additionally, could one of the aircraft persons look at a good book on the Avenger to see what there might be on the system, when it came into use, and on what ships during the war.

The radar used was the APS-20 on TBM-3W version Avengers. I can find:

CVG-1 Bennington: TBM-3 & 3E
CVG-2 Enroute, no aircraft assigned
CVG-5 Klamath Falls, OR: TBM-3 & 3E
CVG-6 Hancock: TBM-3E
CVG-7 Astoria OR: TBM-3 & 3E
CVG-8 Saipan: No aircraft assigned
CVG-9 Alameda CA: No aircraft assigned
CVG-10 Intrepid: TBM-3E
CVG-11 Santa Rosa CA: TBM-3 & 3E
CVG-12 Seattle WA: No aircraft assigned
CVG-13 Puunene T.H. (Territory of Hawaii): TBM-3E
CVG-14 Kahului T.H.: TBM-3 & 3E
CVG-15 Los Alamitos CA: TBM-3E
CVG-16 Randolph: TBM-3 & 3E
CVG-17 Alameda CA: No aircraft assigned
CVG-18 San Diego CA: TBM-3E
CVG-19 Kahului T.H.: TBM-3 & 3E
CVGN-52 Barbers Point T.H. TBM-3E
CVGN-55 Barbers Point T.H. TBM-3E
CVG-80 Ream/NAAS Holtville, CA: TBM-3E
CVG-82 Alameda CA: No aircraft assigned
CVG-83 Essex: TBM-3 & 3E
CVG-84 Holtville/Los Alamitos: TBM-3 & 3E
CVG-85 Shangri-La: TBM-3
CVG-86 Eniwetok: TBM-3E
CVG-87 Ticonderoga: TBM-3E
CVG-88 Yorktown: TBM-3 & 3E
CVG-89 Antietam: TBM-3E
CVGN-91 Bon Homme Richard: TBM-3E
CVG-92 Saipan TBM-3/3PE/3P
CVG-93 Boxer TBM-3E
CVG-94 Lexington:TBM-3E
CVG-95 Hilo T.H.: TBM-3 & 3E
CVG-98 Los Alamitos/San Diego/Thermal/Ventura: TBM-1/1C/3/3E
CVG-99 Saipan: TBM-3/3D/3E
CVG-100 Barbers Point, T.H.: TBM-3 & 3E
CVG-151 Corvallis: TBM-1C/3/3E
CVG-152 Brown Field: TBM-3 & 3E
NACTU Pacific (Night Attack Combat Training Unit): TBF/M-1C/1D/3/3D/3E

No mention of TBM-3Ws in any of the CVE or CVL groups.
None in the VC squadrons
None in any of the USMC listings.
None in the CASUs (Carrier Air Service Units... esentially maintenance depots)

There are 93 "VTB" in "pool" at Alameda, 39 at Eniwetok, 148 at Guam, 8 on Okinawa, 200 at Pearl Harbor, 24 at Roi, 110 at Samar, and 303 at San Diego. No variant info is listed but I doubt they'd really have any of consequence in pool for such a new version.

That's the Pacific Fleet. I'll do the Atlantic when I get home.

ar · Post by ar » Thu Nov 01, 2007 7:56 pm

Not quite certain what the list means.
I would have thought that one would need a list of what ships carried the Cadillac Avengers and at what times.

Tracy White · Post by **Tracy White** » Thu Nov 01, 2007 10:11 pm

Yes, that was my goof; I meant to explain it but got so wrapped up in doing it that I ran out of time to finish it before having to head home.

That is an extract from the Navy index of aircraft dated September 7, 1945, showing all CVG groups that could have possibly been attached to Essex-class carriers. I looked at all of the aircraft in the pacific theater and listed the groups (not squadrons) and types of avengers attached to each. Mostly they were in VT squadrons, but I was looking for oddballs, such as the way night fighter squadrons were broken up amongst different ships earlier in the war. It lists group, location(s, some air groups were spread out), and type of aircraft listed as assigned. Location could be important; if we find one squadron on the east coast with them it's safe to say they never made it out; If we don't find any mention and know that the aircraft flew in March of 1945, then we can probably say they didn't list it there for security or other reasons.

Atlantic Theater:
CVG-3 Oceana: TBM-3E
CVG-4 Groton/Wildwood: TBF-1C/3E
CVG-20 Edenton: TBM-3E
CVGN 53 Quonset, reforming, no aircract
CVBG-74 Ayer/Otis Fields: No TBF/M assigned
CVBG-75 Chincoteague: No TBF/M assigned
CVG-81 Atlantic City/Sanford/Wildwood: TBF-1C/3E
CVGN 90 Quonset, reforming, no aircract
CVG-97 Grosse Ile/Quonset/Sanford: TBF-1/1C/3E
CVG-150 Lake Champlain: TBM-3E
CVG-153 Oceana: TBM-3E
NACTU Atlantic Boca Chica/Marthas Vineyard: TBM-3E

Ahhhhhh here we go.
Under the Miscellaneous section ASDEVLANT
Avengers present at Quonset:
1 TBM-1
2 TBM-3
1 TBM-3W
1 TBM-3D

So, the Navy lists one TBM-3W in its inventory in September. Ranger is listed as in the Pacific at that time, but at San Diego with no aircraft present. The same goes for August and July, when I quickly scan for just those two data points.