Calling all USS Lexington CV-2 fans

[Jerry Phillips]

Mike....yes I know exactly what mystery aerial you are referencing. I've never noticed it aboard any other CV besides CV-5/8...as you said, removed from Hornet, and was aboard Yorktown when she was lost. I believe Dick had a theory that it may have been an early example of a IFF type of thing (?). It is amazing that we can't seem to find an official designation (Mk-?), or even type, all these years later! It is not listed anywhere in Friedman's Radar book. I would guess if any documentation exists, it would be in CV-8's post Midway modifications (SC replaced by CXAM, etc) documented by PHNY. I believe that is when it was removed. The world wonders........

Jerry

[lvsquarerigger]

According to Steve Wiper's latest Lexington book, the antenna was the square version of the MK-3 (also known as "FC"). It can be seen on the MK-34 directors of the Helena in this photo: http://www.navsource.org/archives/04/050/0405006.jpg (The antenna on the high director.)

I finally got on a computer that got through to the image and it seems to correspond very well with the fuzzy item on that photo. Thanks so much.

James

[Michael Vorrasi]

Mike....yes I know exactly what mystery aerial you are referencing. I've never noticed it aboard any other CV besides CV-5/8...as you said, removed from Hornet, and was aboard Yorktown when she was lost. I believe Dick had a theory that it may have been an early example of a IFF type of thing (?). It is amazing that we can't seem to find an official designation (Mk-?), or even type, all these years later! It is not listed anywhere in Friedman's Radar book. I would guess if any documentation exists, it would be in CV-8's post Midway modifications (SC replaced by CXAM, etc) documented by PHNY. I believe that is when it was removed. The world wonders........

Jerry

Dick had postulated that it might be IFF gear, but I still lean towards an early, maybe pre-production, version of SA. It is the right size, has a similar pedestal and a very similar antenna shape to production SA and SA-1. See drawing here: http://www.history.navy.mil/library/online/radar-1.htm. Also, the fact that it is only seen on CV-5 and CV-8 tends to favor the SA theory. If it was IFF, why don't we see it on any other CV's? One would think that IFF gear needed to be similar on all CV's. Can't find it on CV-6, the Lexingtons, Wasp or Ranger. Both CV-5 and CV-8 were in Norfolk around Dec 1941, so this antenna appears to have been installed then. The fact that CV-8 lost it when she upgraded her radar suite to two main air search sets, CXAM and SC, tends to favor the SA theory, as an auxiliary SA set would no longer be needed. Also, the Yorktowns were bigger than Wasp and Ranger, so maybe only larger CV's were considered for two air search sets due to weight considerations. Perhaps CV-8 had the preferred location, looking forward, but CV-5's lower tripod platform had been closed in long before then, and so the funnel top was the next best choice, or they wanted to test to see which location was better. CV-6 had her SC-2 installed where CV-5 had this antenna placed, so maybe they had found it to be a reasonable location for a search antenna. Anyway, the mystery continues...!

[Jerry Phillips]

Mike....I'm completely following your reasoning and logic here. Makes sense, just wish there was some documentation to confirm. CV-8's location of this unit is strange though. Assuming it is an early SA, air-search radar, why would they mount it where they did? Talk about restricting it's search parameters. It could only search the fwd 180 degree arc (maybe not even that), relative to the ship, and then only at a limited angle to the horizon (the upper platform of the tripod top would block overhead search). CV-5's location makes much more sense, guess that's why CV-6 placed her SC-2 in a similar spot? In regards to Lexington, why did they even install the FC? I had thought the Mk-3 was for main-battery fire control, not 5" AA fire? Could the FC be used in conjuntion with CV-2's old Mk-19's? Saratoga also (supposedly) had 2 FC's installed Nov 1941, for the 8" guns still aboard, and were removed when the 8" guns were removed. Kinda strange that a FC was installed Apr 1942 on CV-2, with no 8" left aboard. Maybe the FC had capabilities that I am unaware of in regards of 5" AA fire control.

Jerry

[Michael Vorrasi]

Mike....I'm completely following your reasoning and logic here. Makes sense, just wish there was some documentation to confirm. CV-8's location of this unit is strange though. Assuming it is an early SA, air-search radar, why would they mount it where they did? Talk about restricting it's search parameters. It could only search the fwd 180 degree arc (maybe not even that), relative to the ship, and then only at a limited angle to the horizon (the upper platform of the tripod top would block overhead search). CV-5's location makes much more sense, guess that's why CV-6 placed her SC-2 in a similar spot? In regards to Lexington, why did they even install the FC? I had thought the Mk-3 was for main-battery fire control, not 5" AA fire? Could the FC be used in conjuntion with CV-2's old Mk-19's? Saratoga also (supposedly) had 2 FC's installed Nov 1941, for the 8" guns still aboard, and were removed when the 8" guns were removed. Kinda strange that a FC was installed Apr 1942 on CV-2, with no 8" left aboard. Maybe the FC had capabilities that I am unaware of in regards of 5" AA fire control.

Jerry

I thought about that too on CV-8, but then, if we are talking about planes even as close as 10 or 20 miles out at say 10 or 20,000 feet, what type of angle would be needed? At most 20 degrees upward angle, easily within the unobstructed view for this antenna. To the sides, where the upper platform overhangs the lower a lot more, a bit less, but still, drawing a line out 20 miles and you don't need that much upward angle to cover the altitudes needed. Even the big antennas did not have direct overhead angles. I know CXAM-1 was fixed, while the pre-production CXAM units could tilt upwards in its lower frame, but then, as far as this mystery unit goes, it was a secondary backup set anyway, so would very high angles be needed,? This is true particularly in the case of Hornet, as she had Mk 4 FC radars on her Mk 37 directors for high angle work. When they are that close that you need to tilt up, the SHTF already, anyway. If you look at the antenna, it can actually cover an arc well beyond 180 degrees. All but directly aft for about 15 degrees of arc where the tripod tubes pass through aft of it could be traversed. The funnel location on CV-5 has significant blocked fields directly forward, where the entire tripod mast blocks directly ahead, and also aft, some mainmast interference as well, so neither location is ideal, but again, these would be viewed as backup units. As for the FC on CV-2, I think one of the previous posts in this thread makes mention of connecting it somehow into the 5 inch fire control system, but I have to go back and re-read more fully.

[Jerry Phillips]

In regards to CV-2's FC, the document Tracy posted on pg.20 of this CASF thread provides some insight. The info that the FC received was to be phoned to the Mk-19's, for use by the 5" batteries (!). Needless to say this might not have been an ideal or even workable system. Obviously this was only meant as stop-gap until Lexington received her refit following her Coral Sea action. I have read many books concerning the Battle of the Coral Sea, and have yet to find one reference concerning FC radar contributing to her AA defences. Maybe I know why now! :)

Jerry

[Dick J]

Dick had postulated that it might be IFF gear, but I still lean towards an early, maybe pre-production, version of SA.

Don't forget that we were looking at two different antennas on Hornet. The first was in the lower top, just below the SC set. The second was on the pilothouse roof, essentially replacing the rangefinder. The pilothouse antenna seemed, to a friend who works on radar, to be a dipole antenna, similar in construction to types used for IFF. If so, Hornet may have been testing something that was not ready for production until '43 or later.

[Michael Vorrasi]

Dick had postulated that it might be IFF gear, but I still lean towards an early, maybe pre-production, version of SA.

Don't forget that we were looking at two different antennas on Hornet. The first was in the lower top, just below the SC set. The second was on the pilothouse roof, essentially replacing the rangefinder. The pilothouse antenna seemed, to a friend who works on radar, to be a dipole antenna, similar in construction to types used for IFF. If so, Hornet may have been testing something that was not ready for production until '43 or later.

Hi Dick,
I am inclined to agree about the pilot house roof antenna being IFF gear. It's the one on the tripod lower platform and on Yorktown's funnel that I think might be an early SA. There was surely lots of new gear that was being tested around that time, and it makes these early undocumented antennas a real puzzle palace!

[MartinJQuinn]

Don't forget that we were looking at two different antennas on Hornet. The first was in the lower top, just below the SC set. The second was on the pilothouse roof, essentially replacing the rangefinder. The pilothouse antenna seemed, to a friend who works on radar, to be a dipole antenna, similar in construction to types used for IFF. If so, Hornet may have been testing something that was not ready for production until '43 or later.

on Yorktown's funnel that I think might be an early SA.

Just remember this is a CV-2 thread!

[Michael Vorrasi]

Don't forget that we were looking at two different antennas on Hornet. The first was in the lower top, just below the SC set. The second was on the pilothouse roof, essentially replacing the rangefinder. The pilothouse antenna seemed, to a friend who works on radar, to be a dipole antenna, similar in construction to types used for IFF. If so, Hornet may have been testing something that was not ready for production until '43 or later.

on Yorktown's funnel that I think might be an early SA.

Just remember this is a CV-2 thread!

Sorry for cross-decking. We had some CV-2 content in there when we started!

[Jon C Ryckert]

One question regarding Lex. Since the ship did not have tie down strips I guess that they used some type of padeyes and if they did does anyone know how they were laid out?

[Jon C Ryckert]

I'm back to work on my 1/350 Lex while i wait for some items to be released for my 1/200 Arizona. I am going to run the degaussing cable all the way around the ship because from looking at pics in WP33 (pariculary pages 21, 24 and the two page photos on pages 50 &51).It appears to me at least that it the cables run up above the stem hawse pipe and that also it may be a group of four just like what you see around the stern. I would like to get everyones opinion on this if they don't mind talking about it again. I don't know how to post pics at this time but if you would like to see what I have done so far, e-mail me at j_ryckert@live.com. Jon

[Jerry Phillips]

Jon...concerning Lexington's padeyes....square, and I am not clear in regards to placement. I believe Saratoga had some tie-down strips similar to later USN CV's installed later in the war, but CV-2 did not. CV-2's Degaussing Cables! Still a point of contention/mystery! My thoughts are that the set-up did NOT wrap around the bow (check out pg. 16, CW #11, Lex. Class), but they did wrap around the stern. In some places on the hull there were 4 cables grouped together, others places 2. Then factor in the "brackets" that were installed over the cables along the hull.........(purpose?). Im sure Dick or Mike can add more,,,,curious myself!

Jerry

[Jon C Ryckert]

I had a long reply to your post but for some reason Internet explorer quit working so I'll make this short so that it does not happen again. Please look at the upper pic on page 16 of WP11 and compare to what I have done.

[Jon C Ryckert]

One more. BTW, I have thought that what I may be seeing might only be ropes like what you see on pages 50 and 51 of WP33. A big "THANK YOU" goes out to Martin Quinn for the tip on picture posting.

[Jerry Phillips]

Jon...great workmanship! However, I personally dont believe that the degaussing cables wrapped around the bow. It is my belief that they stopped aft of the anchor p/s postions on the fwd hull. This is based on the few poor photos of the Lex. hull for 1941-42. I believe that the fwd sweep you have depicted is correct (similar to CV-5). BTW, what diameter of plastic rod did you use....looks pretty accurate in dimension. Please keep us udated w/ your build!

Jerry

[Jon C Ryckert]

Thank you Jerry. The rod is .015 from Plastruct. I drilled holes about every 1/8 inch above and below the cable which is probably to far apart for scale but I got lazy. At first I was 'sewing' it with copper wire but it looked too big so I got rid of the wire and went with nylon sewing thread that the soon 'misses to be' gave me but my eyes could'nt see that stuff so I'm looking for something else to use. Wish me luck. I can see your reasoning about how it may have been ran since all of the pics of carriers I've seen show it stopping where you said it did on Yorktown. BTW, in an earlier post you or someone mentiones how Saratoga's was ran in a certain pic. I saw the pic but the quality was poor so I could not make out any detail. Do you know of a better website with the pic? Thanks for the input

[Tracy White]

Pictures of CV-5 and and -6 show the degaussing cables entering the hull forward of the hawse pipe. A drawing I shot photos of for CV-4 shows the cables wrapping around the bow, but I have no photos that show if this was actually installed in this way. THeoretically if could have been done either way, but I have a hard time picturing a bow that fine running cables around it.

[smithec]

Jon...concerning Lexington's padeyes....square, and I am not clear in regards to placement. I believe Saratoga had some tie-down strips similar to later USN CV's installed later in the war, but CV-2 did not. CV-2's Degaussing Cables! Still a point of contention/mystery! My thoughts are that the set-up did NOT wrap around the bow (check out pg. 16, CW #11, Lex. Class), but they did wrap around the stern. In some places on the hull there were 4 cables grouped together, others places 2. Then factor in the "brackets" that were installed over the cables along the hull.........(purpose?). Im sure Dick or Mike can add more,,,,curious myself!

Jerry

Ref the 'brackets' that were installed over the cables. At every point they correspond with the position of ship's boats above the cables - whether located in the pockets or suspended from davits. These 'brackets' are clearly designed to protect the cables from damage as the boats were lowered/hoisted.

[Jon C Ryckert]

Smithec,I noticed that in regards to the boat pockets but didn't even think about it in realtion to the davits.