- Author
- Slatyer, R., Lieut. (P), RANVR
- Subjects
- Ship design and development, History - WW2
- Tags
-
- RAN Ships
- HMAS Shropshire
- Publication
- September 1998 edition of the Naval Historical Review (all rights reserved)
When “Shropshire” was being prepared in England for handing over to the RAN in 1942/43 she was fitted out with a full complement of the current RN equipment. (This is described first. Other equipment which was installed later is then described.)
AIR WARNING – Type 281 – Frequency 90 megacycles. Transmitting antenna on mainmast with transmitter in office at base of mast. Receiving antenna on formast with receiving office on flag deck at base of mast. Antennae rotated in synchronism.
Reports on aircraft detected were fed to the Air Defence Office which was manned by radar ratings with Lieut. R. Major in charge. It was this department that processed the information, plotted enemy and friendly aircraft, and communicated with other ships in the fleet and with our aircraft. Our callsign “Porthole” was made famous by the impressive performance of this team.
SURFACE WARNING – Type 273 – Wavelength 10 cm (Frequency 3,000 megacycles). Located just forward of the after control position. Antenna gyrostabilised, located in a “lantern” structure directly on top of office. Also connected to an accurate range display panel in the TS.
GUNNERY CONTROL – All of the gunnery control radars were combined in an integrated system. All sets operated at the same frequency, around 600 megacycles. Power was supplied from a large motor-generator set with output of 180 volts at 500 cycles and interference was avoided by having a phase difference between the poser supplied to each set.
MAIN ARMAMENT – Type 284 – Antenna mounted on main armament director. Office below decks, accurate range display panel in the TS. Provided range and bearing for main armament fire control.
AUTO BARRAGE UNITS – 4 Type 283 – (One for each turret) – Each set had a control station with display unit on the upper deck. Main office below decks. The purpose of these sets was to enable efficient use of the main armament against dive bombers. We found them quite useful when there where kamikazes around.
Each of these sets was equipped with a small fire control device – a sort of mechanical computer. When the main armament guns were loaded with shells fitted with a time fuse, generally set for a different time, in each barrel, this device would calculate the correct time and fire the gun so that the point at which the shell exploded was the point at which the aircraft would be if it continued on the same course and speed.
4″ ANTI-AIRCRAFT GUNS – Type 285 – Antenna mounted on after director – high angle control position. Office below decks. Provided range and bearing for anti-aircraft fire control.
MULTIPLE POM-POMS – Type 282 – For control of the pom-poms, one set for port and one for starboard.
SURFACE WARNING – Type SG – An American unit of 10cm wavelength fitted soon after we joined the 7th Fleet. Antenna on foremast PPI display in plot, below bridge. Used for navigation as well as surface warning.
AIRCRAFT TRACKING -Type 277 -Wavelength I Ocm. Fitted during a refit in mid. 1945.Antenna on foremast. Office in new extension on port side of bridge structure. Single “dish” antenna controlled for both elevation and bearing enabled this equipment to provide information on the exact location of an aircraft.
RADAR COUNTER MEASURES – Equipment consisted of multi-band receivers and a Type 91 jamming transmitter.