List of World War II British naval radar

From Wikipedia, the free encyclopedia
Jump to: navigation, search

This page is a List of World War II British naval radar.

Nomenclature[edit]

These sets were initially numbered as wireless telegraph (w/t) sets, but a distinguishing prefix of "2" was soon added. Metric sets were numbered in the 28x and 29x series. When centimetric sets arrived with the advent of the cavity magnetron, they were numbered by subtracting 10 from the metric type number they were based on (e.g. the metric Type 284 was replaced by the centimetric Type 274). This was not always possible however, as Types 271 - 274 were already in use for original centimetric sets, thus some metric sets in the Type 28x range had 20 subtracted (e.g. the metric Type 282 was replaced by the centimetric Type 262). Aerial outfits were given a three letter identifier that began with "A".

Suffixing letters indicated the following;

  • B - conversion of sets with separate transmitting (Tx) and receiving (Rx) antennas to single antenna operation.
  • M, P, Q - major set modifications
  • R - addition of range-taking panel
  • U - modification to suit coastal operations
  • W - modification to submarine use
  • X, Y, Z - experimental modifications

Sets[edit]

ASV II[edit]

Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (mm) In service
ASV II 7 176 1700 1940

The first successful Air to Surface Vessel (ASV) radar. ASV II radar allowed Aircraft Carrier based RN Swordfish to locate and attack the German battleship Bismarck in May 1941, from the carriers Victorious and Ark Royal.[1]

ASV III[edit]

Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (mm) In service
ASV III/XI 50 100 1943

The first successful airborne microwave radar. This radar was used on both the Swordfish and Barracuda aircraft. High resolution centimetric radar could detect even small objects, such as the periscope or snorkel of a submerged submarine, making it a highly efficient tool for ASW. The Mk XI was a further development exclusively for the Fleet Air Arm.[2]

Type 79[edit]

Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (mm) In service
79 70 42.8 7,000 1938

Based on the Type 79 w/t, first fitted to Sheffield then Rodney and later Curlew; (40 sets ordered)[3]

Type 86[edit]

Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (mm) In service
86M APH

Fore-runner to Type 286.[citation needed]

Type 262[edit]

Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (mm) In service
262 APE 30 9,670 31

Centimetric fire-control set for 40 mm Bofors weapons. Fitted to Close Range Blind Fire (CRBF) director and STAAG weapon mount. Dish antenna spun off-centre at high speed to produce scanning cone, target lock and blind fire possible.[citation needed]

Type 267[edit]

Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (mm) In service
267 APT 100 214 1,400

Air warning set for submarines replacing Type 291W.[citation needed]

Type 268[edit]

Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (mm) In service
268 AQN 40 9,386 32

Small vessel millimetric target indication and navigation.

Type 271[edit]

Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (mm) In service
271 5 2,997 100 March 1941
271P 90 2,997 100 1943
271Q 90 2,997 100 1943

Type 271 was the original naval centimetric target indication radar, later fitted with a plan position indicator. Modifications P and Q were known as the "Centimetric Mark IV". It had separate transmit and receive aerials, small parabolic dishes stacked on top of each other, and referred to as "cheese" after their shape. The antenna array was carried in distinctive protective perspex "lantern", and initially had to be fitted directly onto the radar office roof due to limitations in coaxial cabling (until suitable waveguides had been developed.) The Type 271 was a vitally important war weapon, as for the first time it allowed escort ships to reliably detect surfaced U-boats or even just their periscopes. It was first fitted in HMS Orchis. 350 sets were ordered.[4] It was fitted widely to escort vessels of corvette and frigate size.

Type 272[edit]

Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (mm) In service
272 90 2,997 100 1941

"Centimetric Mark III" target indication set. Carried in distinctive protective perspex "lantern". For vessels of destroyer and cruiser size.

Type 273[edit]

Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (mm) In service
273 AQN 90 2,997 100 1941

"Centimetric Mark IV" target indication set. This set was based on the Type 271, but was intended for major warships of cruiser and battleship size. It used side-by-side 3 feet (910 mm) wide cheese antennas that were carried in a distinctive protective perspex "lantern". In the Battle of the North Cape, HMS Duke of York identified the target of Scharnhorst at 45,000 yards (41,000 m) using her Type 273 set.[5]

Type 274[edit]

Main Armament Fire Control Radar Set equipped with a 274 aerial on board HMS SWIFTSURE, a Minotaur class cruiser, at Scapa Flow.
Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (mm) In service
274 AUM 500 3,294 91 1944

Centimetric replacement for Type 284. Main armament ranging and shot-spotting set for cruisers and battleships. "Double cheese" antennas.

Type 275[edit]

Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (mm) In service
275 400 3,526 85 1944

Centimetric replacement for Type 285. Destroyer main armament and capital ship secondary fire control set. Fitted to directors HACS Mark VI and Mark 6M and modified American Mark 37. Separate Tx and Rx dishes.

Type 276[edit]

Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (mm) In service
276 AUS / AUJ 500 2,997 100 1944

"Centimetric Mark V" target indication set with continuously rotating antenna. Reduced 4-foot (1.2 m) antennas in aerial outfit AUS.

Type 277[edit]

A general surface search Radar set with a Type 277 aerial fitted to HMS SWIFTSURE, a Minotaur class cruiser at Scapa Flow.
Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (mm) In service
277P AUK 400 2,997 100 1943
277Q ANU 500 2,997 100 1944

"Centimetric Mark V" target indication set with steerable antenna. Aerial Outfit AUK was a parabolic dish, ANU was a cropped paraboloid. Fitted on a "nodding" mount, often used as a height finding set. Superseded in service by Type 278 height finder in County-class destroyers.

Type 279[edit]

Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (mm) In service
279 70 39.9 7,450 1940
279M 70 39.9 7,450 1941

Follow on from Type 79, metric air warning set. Had separate Tx and Rx antennas, combined in Type 279M to single antenna operation. This set also had a secondary surface search with surface and aerial gunnery capability and used a Precision Ranging Panel, which passed accurate radar ranges directly to the HACS table (analog computer).[6][7]

Type 280[edit]

Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (mm) In service
280 25 85 3,500 1940

Metric air warning set with separate Tx / Rx antennas. Based upon Army GL Mark I set, fitted to C-class cruisers converted to anti-aircraft ships. This set used a Precision Ranging Panel, which passed accurate radar ranges directly to the HACS table (analog computer).[8]

Type 281[edit]

281 B Aerial on board HMS SWIFTSURE at Scapa Flow.
Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (mm) In service
281 AQB 350 85 3,500 1940

Metric air warning set with separate Tx / Rx antennas. Type 281B had combined Tx / Rx antenna. First fitted to HMS Dido then HMS Prince of Wales[3] This set also had a secondary surface search and gunnery capability[6] and used a Precision Ranging Panel. The Type 281 ranging system allowed the user to select either a 2000yd to 14000yd or a 2000yd to 25000yd range display with range accuracies of 50 or 75yds RMS, respectively.[9]

Type 282[edit]

Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (cm) In service
282 25 600 50 1941

Decimetric (50cm) ranging set for Bofors 40 mm and "multiple pom-pom" fire control. Fitted on Bofors mounting Mark IV "Hazemeyer" and "Pom-pom Director Mk IV", twin Yagi antennas. Type 282 used a mechanical ranging panel and a 0-5000yd display. Type 282M increased transmission power to 150KW, used a 0 - 6000yd display and introduced Beam Switching, while Type 282P introduced a Precision Ranging Panel.[8]

Type 283[edit]

Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (cm) In service
283 25 600 50 1942

Main armament anti-aircraft barrage fire control set fitted to "barrage director" for cruiser 6-inch (150 mm) and battleship guns. This set used a Precision Ranging Panel and was used to fire the guns automatically using the Automatic Barrage Unit.[8]

Type 284[edit]

Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (cm) In service
284 ASF 25 600 50 1940
284M ASF 150 600 50 1941
284P ASF 150 600 50 1942

Main armament ranging and shot-spotting set for cruisers and battleships with lobe switching beginning with Type 284M[8] to increase accuracy of bearing readings. Prototype fitted on HMS Sardonyx. HMS Southdown received first production set. Used by HMS Suffolk to shadow Bismarck.[10] Type 284P was instrumental in the Battle of the North Cape, effectively allowing HMS Duke of York to sink Scharnhorst blind.[5]

Type 285[edit]

Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (cm) In service
285 25 600 50 1941
285M 150 600 50 1941
285P 150 600 50 1942

Ranging set for anti-aircraft fire control, fitted to HACS directors and rangefinder-directors and used ranging panel L12. Type 285 with six element Yagi antenna with separate Tx / Rx. Type 285P with five element Yagi antenna with combined Tx / Rx function. The Type 285M could provide accurate ranges via the mechanical ranging panel, L12, and bearing information using lobe switching, but height finding was primitive and had to be calculated using maximum signal indication. As such it could not achieve a target lock, and could not offer blind fire capability. Type 285P introduced a Precision Ranging Panel and had 25yd RMS range accuracy.[8]

Type 286[edit]

Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (mm) In service
286M ATQ 214 1,400 1940

Metric target indication set based upon RAF ASV (Air to Surface Vessel) Mark II set. Type 286M had fixed antennas, with a central Tx and an Rx on either side to give some indication of contact bearing. The antennas were fixed, scanning being achieved by conning the ship. Type 286PU and Type 286W were fixed antennas sets for coastal vessels and submarines respectively. Type 286PQ had a steerable combined Tx / Rx antenna from the Type 291 set.

Type 290[edit]

Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (mm) In service
290 100 214 1,400

Metric target indication set, replacement for Type 286.[citation needed]

Type 291[edit]

The conning tower of the submarine is showing a 291W Air Warning Set.
Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (mm) In service
291 100 214 1,400 1941

Metric air warning sets. Original Type 291 had a hand-steered antenna, replaced by Type 291M with power training and plan position indicator. U and W variants for coastal craft and submarines respectively.[citation needed]

Type 293[edit]

A 293 (242) AVR antennae on board HMS SWIFTSURE at Scapa Flow.
Type Aerial outfit Peak power (kW) Frequency (MHz) Wavelength (mm) In service
293M AUR 500 2,997 100 1945
293P AQR 500 2,997 100 1945
293Q ANS 500 2,997 100 1945

"Centimetric Mark V" target indication set, shared transmitter with Type 276 / Type 277 sets. Stabilised "cheese" antenna, 6 feet (1.8 m) diameter in outfit AUR, upgraded to 8 feet (2.4 m) in Type 293P (replaced all Type 293 and Type 276 sets) and to 12 feet (3.7 m) in Type 293Q.

Precision Ranging Panel[edit]

The Precision Ranging Panel (PRP) was an electromechanical transmission and calculating system. The PRP allowed for accurate range determination, range rate determination using radar, and accurate transmission of radar ranges and range rates to fire control computers. The PRP used an electronic timing signal and pip matching to provide very accurate ranges.[8] It also used a power follow up to continuously transmit the correct range rate as long as the target maintained a steady course and speed.[8] The PRP was adapted from the British Army GL, Gun Laying, radar system, and first went to sea in 1939 aboard several C-class cruisers, using the Type 280 radar. By 1941 the PRP was a common feature on the Type 280, 279 and 281 radars, and by late 1941 began to appear on the type 282P, 284P and 285P radar systems.[6]

Mechanical Ranging Panel[edit]

The Type 282, 282M, 285, and 285M radars used a mechanical ranging panel that used a mechanical cursor placed over the ranging display, to estimate range and automatically transmitted the calculated range to either the HACS or FKC fire control computer. Type 285 used Ranging Panel L12 and this also featured range rate estimation with power follow up so that the ranging panel would continue to transmit the correct range without operator intervention as long as the target maintained a steady course at a constant speed.[8]

See also[edit]

Notes[edit]

  1. ^ Horan, Mark E. “With Gallantry and Determination” The Story of the Torpedoing of the Bismarck
  2. ^ Gustin, Emmanuel British ASV Radar
  3. ^ a b Macintyre, September 1967, p.75
  4. ^ Macintyre, September 1967, p.80
  5. ^ a b King George V class Battleships, Roger Chesneau, 2004, Stackpole Books, ., ISBN 1-86176-211-9
  6. ^ a b c Howse, Radar at sea: The Royal Navy in World War II
  7. ^ RADAR IN THE RN AT THE END OF WW2
  8. ^ a b c d e f g h Pout
  9. ^ Weapon Control in the Royal Navy 1935-45, Pout, from The Application of Radar and other Electronic Systems in the Royal Navy in WW2 (Kingsley-editor)
  10. ^ Macintyre, September 1967, p.78

References[edit]

  • Naval Radar, Norman Friedman, 1981, Conway Maritime PRess, ISBN 0-85177-238-2
  • British and Empire Warships of the Second World War, H T Lenton, 1998, Greenhill Books, ISBN 1-85367-277-7
  • Macintyre, Donald, CAPT RN (September 1967). Shipborne Radar. United States Naval Institute Proceedings. 

External links[edit]