Wikipedia

Aichi D3A

(Redirected fromAichi AM-17)

TheAichi D3A(Navy designation "Type 99 Carrier Bomber";Allied reporting name"Val")[a]is aWorld War IIcarrier-bornedive bomber.It was the primary dive bomber of theImperial Japanese Navy(IJN) and was involved in almost all IJN actions, including theattack on Pearl Harbor.

D3A
Aichi D3A1 from carrierAkagi.
General information
TypeCarrier-baseddive bomber
ManufacturerAichi Kokuki KK
Primary userImperial Japanese Navy Air Service
Number built1,495
(479 D3A1)
(1016 D3A2)
History
Introduction date1940[1]
First flightJanuary1938
Retired1945
Developed intoYokosuka D3YMyōjo
Aichi D3A1 dive bombers prepare to take off from a Japanese aircraft carrier during the morning of 7 December 1941 to attackPearl Harbor.
Aichi D3A1 taking off from the carrierAkagiduring theIndian Ocean Raid.
Aichi D3A1s from the carrierShōkakuduring theBattle of the Coral Sea.
Aichi D3A1 of 33rd Air Group over easternJavain early summer 1942.
Aichi D3A1s fromShōkakureturn to their carrier after attacking the U.S. carrierEnterpriseduring theBattle of the Eastern Solomonsin August 1942.
Aichi D3A2 during maintenance. Note thepropeller spinnerthat is missing from the D3A1s in the previous photos.
Aichi D3A2 with a telescopic sight, before takeoff.

The Aichi D3A was the first Japanese aircraft to bomb American targets in the war, commencing withPearl Harborand U.S. bases in thePhilippines,such asClark Air Force Base.They sank moreAlliedwarships than any otherAxisaircraft.[2][3][4]

Design and development

edit

In mid-1936, the Japanese Navy issued the 11-Shi specification for amonoplanecarrier-based dive bomber to replace the existingD1Abiplanethen in service.[1]Aichi,Nakajima,andMitsubishiall submitted designs, with the former two subsequently being asked for two prototypes each.

The Aichi design started with low-mounted elliptical wings inspired by theHeinkel He 70Blitz.It flew slowly enough that the drag from thelanding gearwas not a serious issue, so the fixed gear was used for simplicity.[5]The aircraft was to be powered by the 529kW(709hp)Nakajima Hikari1 nine-cylinderradial engine.

The firstprototypewas completed in December 1937, and flight trials began a month later, after which it was designated as D3A1. Initial tests were disappointing. The aircraft was underpowered and suffered from directional instability in wide turns, and in tighter turns it tended tosnap roll.Thedive brakesvibrated heavily when extended at their design speed of 200knots(370 km/h), and the Navy was already asking for a faster diving speed of 240 knots (440 km/h)[6][7]

The second aircraft was extensively modified before delivery to try to address the problems. Power was increased by replacing the Hikari with the 626 kW (839 hp)Mitsubishi Kinsei3 in a redesignedcowling,and thevertical tailwas enlarged to help with the directional instability. The wings were slightly larger in span and the outer sections of theleading edgeshadwash-outto combat the snap rolls, and strengthened dive brakes were fitted. These changes cured all of the problems except the directional instability, and it was enough for the D3A1 to win over theNakajima D3N1.[8][7]

In December 1939, the Navy ordered the aircraft as theNavy Type 99 Carrier Bomber Model 11(kanjō bakugekiki,usually abbreviated to hạm bạokanbaku.[9]). The production models featured slightly smaller wings and increased power in the form of the 746 kW (1,000 hp) Kinsei 43 or 798 kW (1,070 hp) Kinsei 44. The directional instability problem was finally cured with the fitting of a long dorsalfin-strake which started midway down the rear fuselage, and the aircraft actually became highly maneuverable.[10][7]

In June 1942, an improved version of D3A1, powered by a 969 kW (1,299 hp) Kinsei 54, was tested and designated as D3A2 or theModel 12.The extra power reduced range, so the design was further modified with additionalfuel tanksto bring the total tankage to 900 L (240 US gal), giving it the range needed to fight effectively over theSolomon Islands.Known to the Navy as theModel 22,it began to replace the Model 11 in front-line units in the autumn of 1942, and most Model 11s were then sent to training units. While some late production models of D3A1 were fitted with apropeller spinner,it became a standard with D3A2.[7]

Equipment

edit

Thepilotposition was equipped with a Type 95telescopic gunsightin the earlier models and a Type 99 in the later models, which were used for aiming the bomb during the dive. Theobserver/navigatorposition was equipped with a Type 97 Mk1drift sight,which was a long vertical tube located in the front-left of the observer's seat. In addition, the observer position was equipped with adrift meterthat was mounted on the floor in the front-right of the observer's seat. The observer also operated a Type 96 Mk2radioset that was mounted in front of the observer's seat and behind the pilot's seat. On top of the radio set was a Type 3reflectorcompassfor precise navigation.[11]

Armament was two fixed forward-firing 7.7 mm (0.303 in)Type 97 machine guns,and one flexible 7.7 mm (.303 in)Type 92 machine gunat the rear end ofcockpit,which was operated by the observer. Normal bomb load was a single 250 kg bomb (e.g.,Type 99 No 25semi-APor Type 98 No 25 land bomb) carried under the fuselage, swung out under the propeller on release by a trapeze. Two additional 60 kg bombs (e.g., Type 99 No 6 semi-AP or Type 2 No 6 land bomb) could be carried on wing racks located under each wing outboard of the dive brakes.[7][12]

Initially, D3A dive bombers were painted in silver. During the summer of 1941, the paint finish changed to light olive grey. The color changed again in early 1942 to dark green.[7]

Operational history

edit

An individual D3A dive bomber was commanded by the senior ranking crew member aboard, which could be the observer rather than the pilot.[7]This was in contrast toUS Navy,where the pilot was almost always the commander of a dive bomber. For example,Petty Officer First ClassKiyoto Furutawas serving as a pilot toLieutenantTakehiko Chihaya during theAttack on Pearl Harbor,[7]and later on to LieutenantKeiichi Arimaduring the two carrier battles of theSolomon Islands campaign,[13]both of whom were observers.

The D3A1 first saw combat operation in November 1939, one month prior to its official acceptance as the Navy Type 99 dive bomber. Nakajima sent several examples to the 14th Air group operating atHaikouonHainanisland inSouth China.These D3A1s were commanded byLieutenantSadamu Takahashiand supported theImperial Japanese Armyin thecapture of Nanning,which was intended to cut the supplies coming fromFrench Indochina.After the capture ofNanning,they continued to be operated in the area in 1940. In May 1940,12th Air Groupbecame the second front-line unit to be equipped with the new D3A1 dive bombers. They first participated in thecapture of Yichangand conducted anti-shipping operations onYangtzeriver, west ofYichang,in order to cut the Chinese supplies coming fromChongqing.In September, D3A1 from the 12th Air Group started to flymissions against Chongqing,which was the Chinese capital at the time. After theinvasion of Indochinain autumn 1940, 14th Air Group operated atHanoiand flew missions againstKunmingandBurma Road.[7]

The D3A1 commenced carrier qualification trials aboard theaircraft carriersAkagiandKagaduring 1940, while a small number of aircraft made their combat debut from land bases overChina.[10]Starting with the attack on Pearl Harbor, the D3A1 took part in all major Japanese carrier operations in the first 10 months of the war. They achieved their first major success against theRoyal Navyduring theirIndian Ocean raidin April 1942. D3A1 dive bombers scored over 80% hits[14]with their bombs during attacks on twoheavy cruisersand an aircraft carrier during the operation.

Before the Indian Ocean raid, the established doctrine regarding attacks against ships was to arm all D3A1 dive bombers with semi-AP bombs. On 5 April 1942, an IJN carrier force attackedColomboonCeylonwith half of its complement, while the other half was kept in reserve for strikes against ships. Since a second strike against Colombo was deemed necessary, the dive bombers of the reserve force were rearmed from semi-AP bombs to land bombs. When British heavy cruisers were spotted soon afterwards, the reserve force was sent with a portion of D3A1 dive bombers armed with land bombs. In the subsequent attack, land bombs unintentionally proved very effective in suppressing theanti-aircraft firefrom the ships. As a result, the doctrine was modified in order to intentionally equip the first few D3A1 dive bombers with land bombs. This new method was already implemented for the attack that sankHMSHermesjust four days later, and continued to be used from then on.[7]

During 1942, dive bombing attacks by carrier-based D3A1 and D3A2 bombers significantly contributed to sinking of three US fleet carriers:Le xing tonat theBattle of the Coral Sea,Yorktownat theBattle of MidwayandHornetat theBattle of the Santa Cruz Islands.In addition, they damaged the carrierEnterpriseboth at theBattle of the Eastern Solomonsand at theBattle of the Santa Cruz Islands.[15][13]Besides carrier-based units, D3A dive bombers also operated from land bases during the Solomon Islands campaign, where they participated in theGuadalcanal Campaign,Operation I-Go,Operation SEand Operation RO, and during theNew Guinea campaign,where they participated in theBattle of Milne BayandBattle of Buna–Gona.The main land-based unit to operate D3A dive bombers during these campaigns and battles was the2nd/582nd Air Group.[13][16][17]

During the course of the war, D3A dive bombers often combined their attacks upon enemy warships with the IJNNakajima B5NKatetorpedo bomber; consequently enemy vessels were often sunk by a combination strike of bombs and torpedoes. However, there were occasions when just the D3A's would make the attacks, or at least score the sinking hits. Discounting the Pearl Harbor strike, which also used the B5N for level bombing and torpedo attacks, D3A dive bombers were credited with sinking the following Allied warships (partial list):[18][19]

As the war progressed, there were instances when the dive bombers were pressed into duty asfightersin the interceptor role, their maneuverability being enough to allow them to survive in this role.[23]When theYokosuka D4YSuiseibecame available, the D3A2s ended up with land-based units or operating from the smaller carriers, which were too small to handle the fast-landingSuisei.WhenAmericanforces recaptured thePhilippinesin 1944, land-based D3A2s took part in the fighting, but were hopelessly outdated and losses were heavy. By then, many D3A1s and D3A2s were operated by training units in Japan, and several were modified with dual controls as NavyType 99 Bomber Trainer Model 12s (D3A2-K). During the last year of the war, the D3A2s were pressed back into combat forkamikazemissions.[24]

Operators

edit
Japan

Surviving aircraft

edit

A D3A2 is currently under restoration at thePlanes of FameMuseum inChino, California.[25][26] There are two unrestored D3As on display at theNational Museum of the Pacific Warin Fredericksburg, Texas.[27][28]In 2022, thePearl Harbor Aviation Museumbegan acquiring the remains of a D3A from Papua New Guinea for eventual exhibit.

Specifications (D3A2 Model 22)

edit
Aichi D3A 3-view drawing

Data fromJapanese Aircraft of the Pacific War[29]

General characteristics

  • Crew:2
  • Length:10.195 m (33 ft 5 in)
  • Wingspan:14.365 m (47 ft 2 in)
  • Height:3.847 m (12 ft 7 in)
  • Wing area:34.9 m2(376 sq ft)
  • Empty weight:2,570 kg (5,666 lb)
  • Gross weight:3,800 kg (8,378 lb)
  • Powerplant:1 ×Mitsubishi Kinsei 5414-cylinder air-cooled radial piston engine, 970 kW (1,300 hp) for take-off
1,200 hp (890 kW) at 3,000 m (9,800 ft)
1,100 hp (820 kW) at 6,200 m (20,300 ft)
  • Propellers:3-bladed metal constant-speed propeller

Performance

  • Maximum speed:430 km/h (270 mph, 230 kn) at 6,200 m (20,300 ft)
  • Cruise speed:296 km/h (184 mph, 160 kn) at 3,000 m (9,800 ft)
  • Range:1,352 km (840 mi, 730 nmi)
  • Service ceiling:10,500 m (34,400 ft)
  • Time to altitude:3,000 m (9,800 ft) in 5 minutes 48 seconds
  • Wing loading:108.9 kg/m2(22.3 lb/sq ft)
  • Power/mass:3.9 kg/kW (6.4 lb/hp)

Armament

  • Guns:2x forward-firing 7.7 mm (0.303 in)Type 97 aircraft machine gunsin the forward fuselage upper decking + 1x 7.7 mm (0.303 in)Type 92 machine gunon a flexible mount in the rear cockpit
  • Bombs:1x 250 kg (550 lb) under the fuselage and 2x 60 kg (130 lb) bombs under the wings

See also

edit

Aircraft of comparable role, configuration, and era

Related lists

Notes

edit
  1. ^Note: This code name was applied mid-to-late 1943; more often the D3A was referred to as the "Type 99 navy dive bomber" by Allied forces.

References

edit

Citations

edit
  1. ^abChant 1999,p. 16.
  2. ^Angelucci & Matricardi 1978,p. 142.
  3. ^Worth 2001,p. 170.
  4. ^Casey 1977,p. 87.
  5. ^Francillon 1979,p. 272.
  6. ^Francillon 1979,pp. 272–273.
  7. ^abcdefghijTagaya 2011.
  8. ^Francillon 1969,p. 24.
  9. ^Parshall & Tully 2007,p. 80.
  10. ^abAir International 1987,p. 289.
  11. ^Mikesh 2004.
  12. ^Air International 1987,p. 288.
  13. ^abcLundstrom 2005b.
  14. ^Francillon 1979,p. 274.
  15. ^Lundstrom 2005a.
  16. ^Giang gian 1991.
  17. ^Hata, Izawa & Shores 2011.
  18. ^Brown 1990,pp. 60–125.
  19. ^Stuart, Robert (2006)."Leonard Birchall and the Japanese Raid on Colombo".Canadian Military Journal.
  20. ^Roscoe 1953,p. 96.
  21. ^Parkin 1995,p. 198.
  22. ^Parkin 1995,p. 251.
  23. ^Francillon 1969,p. 25.
  24. ^Air International 1987,p. 209.
  25. ^"Restoration Projects".Planes of Fame Air Museum.Retrieved6 January2022.
  26. ^Taylan, Justin (17 September 2020)."D3A2 Model 22 Val Manufacture Number 3178".Pacific Wrecks.Retrieved6 January2022.
  27. ^Taylan, Justin."D3A2 Model 22 Val Manufacture Number 3357 Tail 582–248".Pacific Wrecks.Pacific Wrecks Inc.Retrieved19 August2016.
  28. ^Taylan, Justin."D3A2 Model 22 Val Manufacture Number 3105".Pacific Wrecks.Pacific Wrecks Inc.Retrieved19 August2016.
  29. ^Francillon 1979,pp. 271–276.

Bibliography

edit
  • Giang gian, bảo (1991).Cấp giáng xuống bạo kích đội ― Nhật Bản hải quân の ヘルダイバー(in Japanese). Hôm nay の đề tài xã.ISBN4875651384.
  • Angelucci, Enzo; Matricardi, Paolo (1978).World Aircraft: World War II, Volume II.Sampson Low Guides. Maidenhead, UK: Sampson Low.ISBN0-562-00096-8.
  • Brown, David (1990).Warship Losses of World War Two.London: Arms and Armour.ISBN0-85368-802-8.
  • Casey, Louis S. (1977).Naval Aircraft.Secaucus, New Jersey: Chartwell Books Inc.ISBN0-7026-0025-3.
  • Chant, Christopher (1999).Aircraft of World War II – 300 of the World's Greatest Aircraft 1939–45.London: Amber Books Ltd.ISBN0-7607-1261-1.
  • Eden, Paul (2007).The Encyclopedia of Aircraft of WWII.London: Amber Books Ltd.ISBN978-1-904687-83-2.
  • Fleischer, Seweryn; Szeremeta, Zygmunt (2001).Aichi D3A Val, Nakajima B5N Kate(in Polish). Warszawa, Poland: Wydawnictwo Militaria.ISBN83-7219-118-2.
  • Francillon, René J. (1979) [1970].Japanese Aircraft of the Pacific War(2nd ed.). London: Putnam & Company Ltd.ISBN0-370-30251-6.
  • Francillon, René J. (1969).Japanese Bombers of World War Two, Volume One.Windsor, Berkshire, UK: Hylton Lacy Publishers.ISBN0-85064-022-9.
  • Hata, Ikuhiko; Izawa, Yasuho; Shores, Christopher (2011).Japanese Naval Air Force Fighter Units and their aces, 1932-1945.London, UK: Grub Street.ISBN9781906502843.
  • Kinzey, Bert (2010).Attack on Pearl Harbor: Japan awakens a Sleeping Giant.Blacksburg, Virginia: Military Aviation Archives.ISBN978-0-9844665-0-4.
  • Lundstrom, John B. (2005a).The First Team: Pacific Naval Air Combat from Pearl Harbor to Midway(New ed.). Annapolis, Maryland: Naval Institute Press.ISBN1-59114-471-X.
  • Lundstrom, John B. (2005b).First Team and the Guadalcanal Campaign: Naval Fighter Combat from August to November 1942(New ed.). Annapolis, Maryland: Naval Institute Press.ISBN1-59114-472-8.
  • Millot, Bernard (December 1976). "Aichi D3A" Val "... la terreur qui tombait du ciel (1)" [Aichi D3A Val... The Terror That Falls from the Sky, Part 1].Le Fana de l'Aviation(in French) (85): 25–31.ISSN0757-4169.
  • Millot, Bernard (January 1977). "Aichi D3A" Val "... la terreur qui tombait du ciel (2)" [Aichi D3A Val... The Terror That Falls from the Sky, Part 2].Le Fana de l'Aviation(in French) (86): 28–33.ISSN0757-4169.
  • "Pacific Predator... the Aichi Type 99".Air International.33(6): 285–290. December 1987.ISSN0306-5634.
  • Mikesh, Robert C. (2004).Japanese Aircraft Equipment: 1940-1945.Schiffer Publishing.ISBN0764320971.
  • Parkin, Robert S (1995).Blood on the Sea: American Destroyers Lost in World War II.New York: Sarpedon Publishing.ISBN1-885119-17-8.
  • Parshall, Jonathan; Tully, Anthony (2007).Shattered Sword: The Untold Story of the Battle of Midway.Washington D.C.: Potomac Books.ISBN9781574889246.
  • Richards, M. C.; Smith, Donald S. (1974).Aichi D3A ('Val') & Yokosuka D4Y ('Judy') Carrier Bombers of the IJNAF.Aircraft in Profile, Volume 13. Windsor, Berkshire, UK: Profile Publications. pp. 145–169.ISBN0-85383-022-3.
  • Roscoe, Theodore (1953).United States Destroyer Operations in World War II.Annapolis, Maryland: United States Naval Institute.ISBN0-87021-726-7.
  • Smith, Peter C. (1999).Aichi D3A1/2 Val.Ramsbury, UK: The Crowood Press.ISBN1-86126-278-7.
  • Tagaya, Osamu (2011).Aichi 99 Kanbaku 'Val' Units of World War 2.Combat Aircraft #63. Botley, UK: Osprey Publishing.ISBN978-1841769127.
  • Worth, Richard (2001).Fleets of World War II.New York: Da Capo Press.ISBN978-0-306-81116-6.
edit
Wikimedia Commons has media related toAichi D3A.
Retrieved from "https://en.wikipedia.org/w/index.php?title=Aichi_D3A&oldid=1260059190"