Hello,
Just reaching out to the community to find out more about some equipment onboard the PB4Y-2.
Currently in WT none of the PB4Y’s radio gear is modelled; with the arrival of the PBM-5A with the AN/APS-31 surface search radar arriving this battle pass, I wanted to look closer at the PB4Y-2.
According to the Standard Aircraft Characteristics of the PB4Y-2 - August 15, 1948:
Just a reminder before we continue: (RADAR = RAdio Detection And Ranging)
We can see that depending on when the aircraft was either equipped with an AN/APS-2G, or AN/APS-15B.
The AN/APS-2, or in UK service, the ASV Mark V, has a radar wavelength of 10 cm, operating at approximately 3.3 GHz. Since the game is following the current NATO band classifications, and puts the PBM-5A’s APS-31 as an I-Band radar, the APS-2 is an F-Band radar.
The AN/APS-15B was a navigation and search radar operating at 9.375 GHz, making it an I-Band radar. PRF of 622 Hz, pulse width of 1 µs, ± 150 m accuracy, 40 kW peak power, 50 W average power, beam width of 3 degrees, antenna rotation of 20 rpm, and max instrumented range of 100 miles (161 km).
As side from that, the only other thing that caught my attention was the “Liaison” electronics listed, as ATC/RAX. Searching this online yields almost nothing. However I did find this in the Bibliography of Scientific and Industrial Reports, Volume 1, Issue 17, 1946.
Merely stating how to convert the communication equipment to a jammer. It sources NAVAER 08-5S-135. This isn’t available on the internet. Given the nature of the description, this is probably a communication receiver as well as a communication jammer.
Below are is a picture from 1946 showing both the antenna positions.
From left to right, the DF antenna has not been identified yet, the intercept antenna is the AN/APR-2, the jamming antenna is the AN/APQ-2, the radar antenna (incorrectly marked as the intercept antenna) is the AN/APS-2 or AN/APS-15, the second intercept antenna (incorrectly marked as radar antenna) is most probably the AN/APR-7, the final thing of note is the receiving jamming antenna, this is likely the ATC/RAX.
More in depth breakdown:
In these photos, the AN/APQ-2B is identified, as well as the radar nacelle for the APS-2 or 15.
The AN/APQ-2B was a radar barrage jammer in the 450-720/750 MHz range. B and C-Band.
The AN/APR-2 was a “90-1000 MHz Auto-Search and Recording Receiver”; this would be A through C-Bands.
As mentioned above, the second intercept antenna is likely the APR-7, as the AS-125 antenna is associated with it. However it may also be associated with the APR-11. However no definitive details on the APR-11 have been found by me. Below is a page about the AN/APR-7 from the GRAPHIC SURVEY of Radio and Radar Equipment Used by the Army Air Forces, 1 February 1945.
APR-7: receives in the range of 1-3 GHz, Top of C-Band through the bottom of F-Band
The following image shows the ECM operator station, who has the ability to intercept radio signals (APR-2 + APR-7), analyze the signals, direction find (AN/?), and jam (APQ-2B).
Eventually War Thunder will shift into ECM defenses, and the APR-2 & APR-7 seem to be able to provide a very primitive form of radar warning. These older aircraft shouldn’t be overlooked, as they are the beginning of airborne electronic warfare.
If anyone has any additional information not found here on the PB4Y-2; feel free to share.
Sources:
PB4Y-2 Standard Aircraft Characteristics - August 15, 1948
Bibliography of Scientific and Industrial Reports, Volume 1, Issue 17, 1946
https://en.wikipedia.org/wiki/Radio_spectrum
https://en.wikipedia.org/wiki/AN/APS-2
https://www.radartutorial.eu/19.kartei/11.ancient4/karte016.en.html
https://www.designation-systems.net/usmilav/electronics.html#_JETDS_AN_Listings
https://aafradio.org/sidebar/PB4Y2_Line_Maintenance_Manual.html
https://aafradio.org/docs/APQ-2.html
https://www.radionerds.com/images/6/6d/AIR_RAD_HTM.txt
https://hangarthirteen.org/wp-content/uploads/2020/10/Graphic-Survey-of-AAF-Radio-Radar-Equipment-Pt-1.pdf