141:, had an inconveniently long minimum detection range. Thus as the aircraft approached the target, it would disappear off the radar at a range that was too great to allow it to be seen by eye at night without some form of illumination. At first, aircraft solved this problem by dropping flares to illuminate the area, but since the flare illuminated only the area directly beneath the aircraft, a series of flares in succession would have to be dropped until the submarine was spotted. Once it was spotted, the aircraft would circle back to attack, the entire process giving the submarine time to dive.
188:
154:, an RAF personnel officer, devised a solution after chatting with returning aircrew. This was to mount a searchlight under the aircraft, pointed forward and allowing the submarine to be spotted as soon as the light was turned on. He then developed the Leigh Light on his own, in secret and without official sanction—even the Air Ministry were unaware of its development until shown the completed prototype. At first it was difficult to fit on aircraft due to its size. Leigh persisted in his efforts to test the idea and garnered the support of the Commander-in-Chief of Coastal Command, Sir
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Before the Leigh Light, not a single enemy submarine had been sunk in over five months, but in combination with radar, it was so overwhelmingly effective that many German submarine crews chose to surface during the day so that they could at least see the aircraft attacking them and have a chance to
236:
biplane torpedo bomber was trialled with a Leigh Light under the lower port wing, with a large battery pack slung under the fuselage where the torpedo would normally be carried. The armament was a rack of anti-submarine bombs carried under the other wing. With such a heavy load performance was poor
116:
in an effort to counter the combination of ASV and Leigh Light. Metox provided the submarine crew with early warning that an aircraft using radar was approaching. Because the radar warning receiver could detect radar emissions at a greater range than the radar could detect vessels, this often gave
203:
The
Nacelle type, fitted on Catalinas and Liberators, was a 20-inch (510 mm) searchlight mounted in a nacelle 32 inches (810 mm) in diameter slung from the bomb lugs on the wing. The controls were electric and the maximum beam intensity was 90 million candelas without the spreading
199:
The Turret type, fitted on
Wellington aircraft, was a 24-inch (610 mm) searchlight mounted in a retractable under-turret controlled by hydraulic motor and ram. The maximum beam intensity was 50 million candelas without the spreading lens and about 20 million candelas with the lens.
105:
hit upon the idea of using a searchlight that would be switched on just when the target was about to disappear on radar. The U-boat had insufficient time to dive and the bombardier had a clear view of the target. Introduced in June 1942, it was so successful that for a time German submarines were
229:, piloted by American Wiley B. Howell. In the previous five months not one submarine had been sunk, and six aircraft had been lost. The Leigh Light turned the tables, and by August the U-boats preferred to take their chances in daytime when they had some warning and could fight back.
237:
with a top speed marginally above the stall speed. A Swordfish III was also fitted with a Leigh Light under the starboard wing, at some point, although it is unclear where the battery pack was stowed as the ASV radar scanner apparently filled the torpedo area.
178:
interception. After trials they too eventually decided to use Leigh's system, but it was not until mid-1942 that aircraft started being modified to carry it. Development assistance and production was by Savage and
Parsons Ltd. of Watford led by Jack Savage.
144:
Eventually, time-delayed flares were developed that allowed the attacking plane time to circle. The flare was fired into the air from a buoy previously dropped by the plane. The surfaced submarine could then be seen in silhouette as the plane approached.
162:
that conveniently already had the necessary generator on board (it had been used for anti-magnetic mining operations using a large electromagnet) was modified with a retractable "dustbin" holding the lamp and proved the concept sound.
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demonstrated that the radar's minimum range of about 1 kilometre (0.62 mi) meant that the target was still invisible when it disappeared off the radar display. Efforts to reduce this minimum were not successful, so wing commander
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intercepting U-boats moving to and from their home ports on the coast of France. The first submarine to be successfully sighted was the
Italian submarine
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Giorgerini, Giorgio (2002). Uomini sul fondo : storia del sommergibilismo italiano dalle origini a oggi. Milano: Mondadori. pp. 518–20.
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forced to switch to charging their batteries during the daytime, when they could at least see aircraft approaching.
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Deep Sea
Hunters: RAF Coastal Command and the War Against the U-Boats and the German Navy 1939–1945
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and midway along the bay provided triangulation to assess the accuracy of the bombing attempt.
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the U-boat enough time to dive. Having expected this, the Allies introduced the centimetric
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lens and about 17 million with the lens. Total weight was 870 lb (390 kg).
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countered these radars, by this time the U-boat force was already damaged beyond repair.
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Uomini sul fondo : storia del sommergibilismo italiano dalle origini a oggi
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decided that the idea was worthwhile, but that they should instead use the
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The Secret War, by Brian
Johnson, Pen And Sword Military Classics, 1978,
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of 24 inches (610 mm) diameter fitted to a number of the
British
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218:, on the night of 3 June 1942, and the first confirmed kill was the
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aircraft of the Royal Air Force
Coastal Command, 26 February 1944
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507:"Second World War bombing range indicator and observation post"
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Photograph of a destroyed U-boat illuminated in Leigh Lights
387:, by Brian Johnson, Pen And Sword Military Classics, 1978,
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The
Observation Post at Putsborough overlooking Morte Bay
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were built for Leigh Light training. A buoy anchored in
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The
Indicator arrow at Putsborough overlooking Morte Bay
121:, regaining control of the battle. Although the German
1612:
World War II military equipment of the United Kingdom
423:"The Leigh Light For Night Anti-Submarine Operations"
411:, 27 September 1945, page 350. Accessed October 2010.
274:
The observation post and concrete indicator arrow at
250:
for his part in the development of the Leigh Light.
485:(1st ed.). London: Putnam. pp. 236–260.
195:Two types of Leigh Light entered operational use:
225:, sunk on 5 July 1942 by a Vickers Wellington of
1598:
1622:Military equipment introduced from 1940 to 1944
361:Anti-Submarine Warfare: An Illustrated History
295:fire their anti-aircraft weaponry in defense.
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200:Total weight was 1,100 lb (500 kg).
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282:was used as a target. Two other sites at
36:A Leigh Light fitted under the wing of a
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31:
612:Atlantic U-boat campaign of World War I
351:
14:
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480:
448:. Milano: Mondadori. pp. 518–20.
330:
617:Battle of the Atlantic (World War II)
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474:
64:. It was a powerful (22 million
565:Technical details of the Leigh Light
364:. Seaforth Publishing. p. 111.
357:
96:Early night operations with the new
24:
509:. Historic England. 30 August 2019
25:
1633:
764:List of wolfpacks of World War II
558:
337:. Pen and Sword. pp. 61–79.
98:air-to-surface-vessel (ASV) radar
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1515:Unrestricted submarine warfare
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425:. RAF Liberator Squadrons, PC
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627:Mediterranean (World War II)
444:Giorgerini, Giorgio (2002).
421:Peter Clare (22 July 2009).
316:. rafb24.com. Archived from
312:Peter Clare (22 July 2009).
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622:Mediterranean (World War I)
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86:to help them spot surfaced
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1292:French battleship
731:World War II commanders
314:"Leigh Light Operation"
109:Germany introduced the
726:World War I commanders
331:Bowman, Marin (2014).
271:
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220:German submarine
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160:Vickers Wellington DWI
152:Humphrey de Verd Leigh
114:radar warning receiver
103:Humphrey de Verd Leigh
62:Battle of the Atlantic
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38:Consolidated Liberator
27:Submarine search light
481:Taylor, H.A. (1974).
269:
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133:Early air-to-surface
58:anti-submarine device
35:
1464:Metox radar detector
686:Uncompleted projects
405:Death of Jack Savage
358:Owen, David (2007).
320:on 11 November 2009.
246:was also given the
1444:FuG 200 Hohentwiel
470:Wings on my Sleeve
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234:Fairey Swordfish I
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166:At this point the
158:. In March 1941 a
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1484:Sieglinde (decoy)
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990:Major engagements
371:978-1-78346-897-3
344:978-1-78383-196-8
156:Frederick Bowhill
137:sets, namely the
119:ASV Mk. III radar
16:(Redirected from
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1454:Leigh light
1439:Elektroboot
1269:World War I
1043:World War I
997:Convoy SC 7
931:Steinbrinck
746:Karl Dönitz
276:Putsborough
244:Peter Cundy
129:Development
73:searchlight
46:Leigh Light
18:Leigh light
1601:Categories
1422:Technology
1392:Courageous
1302:Formidable
1286:Cornwallis
917:Schlieffen
868:Pfadfinder
847:Kreuzotter
784:Delphin II
709:Commanders
640:Operation
634:Regenbogen
632:Operation
533:8804505370
492:037000065X
455:8804505370
299:References
284:Woolacombe
172:Turbinlite
139:ASV Mk. II
93:at night.
70:carbon arc
1469:Mousetrap
1408:Royal Oak
1406:HMS
1398:HMS
1390:HMS
1382:HMS
1376:Ark Royal
1374:HMS
1355:HMS
1339:HMS
1323:HMS
1300:HMS
1284:HMS
1278:Britannia
1276:HMS
1017:Black May
945:Streitaxt
938:Siegfried
805:Eisteufel
756:Wolfpacks
642:Deadlight
513:4 October
429:14 August
280:Morte Bay
183:Operation
1563:Valentin
1559:Germany
1503:Concepts
1449:Hedgehog
1325:Majestic
1317:Peresvet
1070:Flanders
1023:Bismarck
966:Weddigen
959:Vorwärts
903:Rossbach
889:Raubgraf
826:Hartmann
254:Training
66:candelas
1580:Dora II
1548:Lorient
1544:France
1494:Snorkel
1357:Triumph
1349:Suffren
1341:Russell
1309:Gaulois
1101:Regions
1075:Kurland
952:TĂĽmmler
924:Seewolf
854:Leuthen
840:Kiebitz
812:Endrass
791:Dränger
770:BlĂĽcher
698:Classes
601:U-boats
215:Torelli
91:U-boats
1575:Dora I
1570:Norway
1479:Q-ship
1384:Barham
1294:Danton
910:Schill
896:Rösing
798:Eisbär
777:Borkum
661:German
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409:Flight
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176:bomber
88:German
1530:Bases
1489:Sonar
1400:Eagle
1025:chase
882:Prien
875:Pfeil
833:Hecht
666:Types
222:U-502
135:radar
123:Naxos
111:Metox
1262:sunk
1080:Pola
980:Wolf
973:West
861:Lohs
546:ISBN
529:ISBN
515:2020
487:ISBN
450:ISBN
431:2013
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