What is the purpose of the wire (not shown in illustration) that runs from the mast just in front of the cockpit to the top front of the vertical stabilizer?
Posted on 06/19/2011 2:51:42 PM PDT by Lonesome in Massachussets
What is the purpose of the wire (not shown in illustration) that runs from the mast just in front of the cockpit to the top front of the vertical stabilizer?
My grandsons' other grandfather and I were speculating about the purpose of a steel wire running from the mast just in front of the cockpit to forward part of the vertical stabilizer. Thought it might be an antenna for low power communications between members of the squadron. Anyone know for sure it's purpose?
I saw the Screamin Rebels yesterday on their way to the flyover at MIS a few miles south of here.
Six of them just went over the house several times yesterday. Time trials for the Reno Air Races.
Six of them just went over the house several times yesterday. Time trials for the Reno Air Races.
Must be a fair sized team. 4 T6 Texans from the Screamin Rebels were circling over here yesterday before the Saturday Michigan race.
Today I got a gander at the A10 Warthogs again. I think they’re out of Selfridge ANG base.
Specifically, an HF Radio Antenna. Long-range communications, and in any case higher frequencies for comm weren’t all that easy prior to the development of semiconductor technology. . .
I remember working on a P-51D that had push button VHF radio channel select in it.
Back when the AT-6 was introduced HF the the gig and it took a longer antenna at the time.
If you look for it, even in the movies at times, you will see antenna staffs that go from in front of the cockpit to the aft emmpenage or up the tail of aircraft on the WWII vintage warbirds.
Not true, even magnetron were used for radar that generated microwave. The magnetron IS a vacuum tube and is still being used in many airborne radar systems.
I wish I were there!
I miss the Warbird circuit!
It could be HF antenna, but I think more likely a LF antenna for range station navigation that was in use at the time. LF is just below the broadcast band from about 190 kHz to 550 kHz. Range stations broadcast a beacon that gave a steady tone if you were on course a dit da or a da dit depending on what side of the course you were on.
I have navigated by them back in the 50’s but they no longer exist.
Also I am pretty sure that VHF communication for aircraft was in common use during WWII. HF was usually used only for longer ranges and would not be needed in a trainer like the T-6.
A T-6, with Clipped wings ( 6 ft total ) a DC-4 engine and the cockpit moved back to the passengers slot and a Bubble Canopy...
Oh man do I like this thing. Find the videos on YouTube, It goes
I believe the wire in question is an HF antenna.
In late 1941 the FCC had notified American radio “hams” of the scheduled re-assignement of the 75meter band ,i.e. several hundred kilocycyles in the 3.75 mc range to be used for aircraft crew training purposes.
There was a nice little ARC-5 radio set that operated in that range.They were simple to operate,reliable and used standard tubes.
Later the military did employ the much more complicated and expensive SCR-522 aircraft set in the 100-156 Mc range.
Reliable VHF tubes were a requirement and a development of the war;only hardy experimenters were working much above 60 Mc. Radios in the 100-156 commonly use a one to two foot rod antenna.
Magnetrons were expensive and not suited for voice communication;the magnetron and other radar tubes send out very short pulses of high power but the tube is off much more than it is on.
The LF direction-finding antenna would more likely have been a small loop that could be swiveled;the 180 degree ambiguity of simple directional antennas is thought to have lead to the loss of the training flight off the Florida coast(Bermuda Triangle) during WW2.
“The LF direction-finding antenna would more likely have been a small loop that could be swiveled;the 180 degree ambiguity of simple directional antennas is thought to have lead to the loss of the training flight off the Florida coast(Bermuda Triangle) during WW2.”
The range station navigation I speak of is a different animal than using a loop for direction finding. To fly a range station only required a LF receiver, headphones and a ordinary wire antenna. My father taught instrument training during WWII in the Navy in SNJ’s ( Navy version of T-6) and we have discussed it.
The loop antenna later developed into the ADF ( automatic direction finder) which not only required a loop but also a sense antenna similar to wire antenna shown on the pictured on the T-6.
BTW the lost Bermuda triangle flight was in TBM Avengers, not T-6/SNJ’s and was shortly after the end of WWII (December 1945)
I am not discounting that the antenna in question might be an HF antenna, but I believe that it also may have been a LF antenna for range station navigation.
I just talked to a friend that has an SNJ under restoration. It is the exact airplane that was used for the photographs in the Navy training manual, so I assume it is an early one.
He is very familiar with SNJ’s and tells me his originally had a combo VHF comm radio and intercom. It also had the wire antenna and a LF receiver for range station navigation. It did not have a HF comm radio.
Of course the Army Air Corp T-6’s could have been equipped differently.
Hoosierham, I assume by your screen name that you may be a ham. If so
73 de W5HJ.
Of course the scheduled re-assignments hardly had time to take effect when the Japanese Empire attacked Pearl Harbor and then all radio ham bands were diverted to the war effort. I began listening to hams on old floor model RCA in 1965 when AM was the usual mode.That radio had a LF band and a couple navigation beacons came in around 300? kc but I didn't do well with Morse Code.Those stations gave weather reports,too. And then there was the boats on the marine band. The radio fell victim to the tendency of inquisitive boys to take things apart.Mea culpa.Eventually replaced with a second-hand Allied that also had low and marine bands. Oh,I am also a voracious reader of things scientific like old books and magazines even though sometimes I mis-remember the details.
Here is a link that may interest you.
http://www.designation-systems.net/usmilav/electronics.html#_JETDS_AN_Listings
It even lists what aircraft the radios were used in. I spent some time there and was unable to find any T-6 or SNJ listed. But it is a quite extensive listing and I may have missed it. Most listed aircraft are combat or combat support, not trainers.
I am quite familiar with the ARC 5 series, as my first HF ham station was a 40 meter ARC 5 receiver with home brew power supply and home brew CW transmitter in 1963.
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Being a pilot since 1956 and ham since 1963 and plus working in communications and maintaining my own avionics, I have a keen interest in aircraft radios.
For radar, yes. But VHF Comms only really took off after semiconductors became common. . .
“But VHF Comms only really took off after semiconductors became common. . “
Most aircraft were using VHF long before semiconductors were commonplace. I know because I flew many of them with tube type radios. I am not sure when exactly semiconductors started to be used in VHF avionics, but it was probably in the late 60’s and most still used tube type final amps.
Actually the early semiconductors did not operate well at VHF frequencies.
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