The Douglas SBD Dauntless is a World War II American naval scout plane and dive bomber that was manufactured by Douglas Aircraft from 1940 through 1944. The SBD ("Scout Bomber Douglas") was the United States Navy's main carrier-based scout/dive bomber from mid-1940 through mid-1944. The SBD was also flown by the United States Marine Corps, both from land air bases and aircraft carriers. The SBD is best remembered as the bomber that delivered the fatal blows to the Japanese carriers at the Battle of Midway in June 1942.Parker, Dana T. Building Victory: Aircraft Manufacturing in the Los Angeles Area in World War II, pp. 25–34, Cypress, CA, 2013. . The type earned its nickname "Slow But Deadly" (from its SBD initials) during this period. Even though the SBD was ostensibly replaced by the Curtiss SB2C Helldiver in 1944, experience showed the earlier plane performed better, and both models fought side-by-side until the end of the war.
During its combat service, the SBD proved to be an effective naval scout plane and dive bomber. It possessed long range, good handling characteristics, maneuverability, potent bomb load, and great diving characteristics from the perforated dive brakes. A land-based variant of the SBD – omitting the arrestor hook — was purpose-built for the U.S. Army Air Forces, as the A-24 Banshee. Due to lack of specialized training, though, the Army's experience was not as successful, and by the middle of 1943, the A-24 was considered by pilots to be too vulnerable for service, owing to its armament and slow speed, and was relegated to noncombat roles.
Design and development
Design work on the Northrop BT-1 began in 1935. In 1937, the Northrop Corporation was taken over by Douglas, and the active Northrop projects continued under Douglas Aircraft Corporation.Francillon, 1979 The Northrop BT-2 was developed from the BT-1 by modifications ordered in November 1937, and provided the basis of the SBD, which first entered service in mid-1939. Ed Heinemann led a team of designers who considered a development with a Wright Cyclone engine. The plane was developed at the Douglas El Segundo, California, plant, and that facility, along with the company's Oklahoma City plant, built almost all the SBDs produced. One year earlier, both the U.S. Navy and Marine Corps had placed orders for the new dive bomber, designated the SBD-1 and SBD-2 (the latter had increased fuel capacity and different armament). The SBD-1 went to the Marine Corps in late 1940, and the SBD-2 to the Navy in early 1941, replacing the SBU Corsair and Curtiss SBC Helldiver biplane squadrons on US carriers. Distinctive perforated split flaps or "dive brakes" had been incorporated into the BT-1 to eliminate tail buffeting during diving maneuvers.Parker, Dana T. Building Victory: Aircraft Manufacturing in the Los Angeles Area in World War II, p. 28, Cypress, CA, 2013. . Unusual for carrier aircraft, folding wings were not chosen for the design, opting instead for structural strength.
The next version was the SBD-3, which began manufacture in early 1941. It had increased armor, self-sealing fuel tanks, and four machine guns. The SBD-4 provided a 12-volt (up from 6-volt) electrical system and a few were converted into SBD-4P reconnaissance aircraft.
The next (and most produced) version, the SBD-5, was produced mostly in the Douglas plant in Tulsa, Oklahoma. This version was equipped with a engine and an increased ammunition supply. Over 2,400 of these were built. A few of them were shipped to the Royal Navy for evaluation. In addition to American service, the SBD saw combat against the Japanese Army and Navy with No. 25 Squadron of the Royal New Zealand Air Force, but the RNZAF soon replaced them with the larger, faster, heavier. and land-based Vought F4U Corsairs.
Some SBDs were also flown by the Free French Air Force against the German Heer and Luftwaffe. SBDs were also sold to Mexico.
The final version, the SBD-6, had more improvements, but its production ended during the summer of 1944.
The U.S. Army Air Forces (USAAF) had its own version of the SBD, called the A-24 Banshee. It lacked the tail hook used for carrier landings and a pneumatic tire replaced the solid tail wheel. First assigned to the 27th Bombardment Group (Light) at Hunter Field, Georgia, A-24s flew in the Louisiana maneuvers of September 1941. The three versions of the Banshee (A-24, A-24A and A-24B) were flown by the USAAF to a very minor degree in the early stages of the war."Douglas A-24". National Museum of the United States Air Force. The USAAF used 948 of the 5,937 Dauntlesses built.
Operational history
U.S. Navy and Marine Corps
U.S. Navy and Marine Corps SBDs saw their first action at Pearl Harbor, when most of the Marine Corps SBDs of Marine Scout Bombing Squadron 232 (VMSB-232) were destroyed on the ground at Ewa Mooring Mast Field. Most U.S. Navy SBDs flew from their aircraft carriers, which did not operate in close cooperation with the rest of the fleet. Most Navy SBDs at Pearl Harbor, like their Marine Corps counterparts, were destroyed on the ground.Salamander Books, Ltd. 1974. . On 10 December 1941, SBDs from sank the Japanese submarine I-70. In February–March 1942, SBDs from the carriers , , and , took part in various raids on Japanese installations in the Gilbert Islands, the Marshall Islands, New Guinea, Rabaul, Wake Island, and Marcus Island.
The first major use of the SBD in combat was at the Battle of the Coral Sea, where SBDs and TBD Devastators sank the Japanese light aircraft carrier (CVL) and damaged the Japanese fleet carrier . SBDs were also used for antitorpedo combat air patrols, and these scored several victories against Japanese aircraft trying to attack Lexington and Yorktown. Their relatively heavy gun armament with two forward-firing M2 Browning machine guns and either one or two rear flexible-mount AN/M2 machine guns was effective against the lightly built Japanese fighters, and many pilots and gunners took aggressive attitudes to the fighters that attacked them. SBD pilot Stanley "Swede" Vejtasa was attacked by three A6M2 Zero fighters; he shot down two of them and cut off the wing of the third in a head-on pass with his wingtip."USAF UA Vejtasa bio." au.af.mil. Retrieved: 23 August 2010.
The SBD's most important contribution to the American war effort came during the Battle of Midway in early June 1942. Three squadrons of Navy SBD dive bombers attacked and sank or fatally damaged all four Japanese fleet carriers present, disabling three of them in the span of just 6 minutes (, , ), and later in the day, . Joined by additional planes from the Hornet they also caught two straggling heavy cruisers of the Midway bombardment group of four, heavily damaging them, with eventually sinking.
At the Battle of Midway, Marine Corps SBDs were not as effective. One squadron, VMSB-241, flying from Midway Atoll, was not trained in the techniques of dive bombing with their new Dauntlesses (having just partially converted from the SB2U Vindicator). Its pilots resorted to the slower but easier glide bombing technique. This led to many of the SBDs being shot down during their glide, although one survivor from these attacks, now on display at the National Naval Aviation Museum, is the last surviving aircraft to have flown in the battle. The carrier-borne squadrons were effective, especially when they were escorted by Grumman F4F Wildcats.[The Dauntless Dive Bomber of World War Two, by Barrett Tillman, Naval Institute Press, 2006] The success of dive bombing resulted from one important factor,
SBDs played a major role in the Guadalcanal campaign, operating off both American carriers and from Henderson Field on Guadalcanal. SBDs proved lethal to Japanese shipping that failed to clear New Georgia Sound (the Slot) by daylight. Losses inflicted included the carrier , sunk near the Solomon Islands on 24 August. Three other Japanese carriers were damaged during the six-month campaign. SBDs sank a cruiser and nine transports during the Naval Battle of Guadalcanal.
In the Atlantic Ocean, the SBD saw action during Operation Torch, the Allied landings in North Africa in November 1942. The SBDs flew from and two escort carriers. Eleven months later, during Operation Leader, the SBDs had their European debut, when aircraft from Ranger attacked Nazi German shipping around Bodø, Norway.Smith 2007, p. 186.
By 1944, the U.S. Navy began replacing the SBD with the more powerful SB2C Helldiver. During the Battle of the Philippine Sea in June 1944, a long-range, twilight strike was made against the retreating Japanese fleet, at (or beyond) the limit of the combat radius of the aircraft. The force had about 20 minutes of daylight over their targets before attempting the long return in the dark. Of the 215 aircraft, only 115 made it back. Twenty were lost to enemy action in the attack, and 80 were lost as one-by-one they expended their fuel and had to ditch into the sea.Potter 2005, p. 170. In the attack were 26 SBDs, all of which made it back to the carriers.
The Battle of the Philippine Sea was the last major engagement of the carrier-borne SBDs. Marine squadrons continued to fly SBDs until the end of the war. Although the Curtiss Helldiver had a more powerful engine, a higher maximum speed, and could carry nearly 1000 pounds more in bomb load, many of the dive bomber pilots preferred the SBD, which was lighter and had better low-speed handling characteristics, critical for carrier landings.
The Dauntless was one of the most important aircraft in the Pacific War, sinking more enemy shipping in the Pacific than any other Allied bomber. Barrett Tillman, in his book on the Dauntless, claims that it has a "plus" score against enemy aircraft, meaning it was credited with more victories over enemy planes than losses from enemy action. This is considered to be a rare event for a nominal "bomber".Tillman, Barrett The Dauntless Dive Bomber of World War Two. Annapolis, Maryland: Naval Institute Press, 1976. .
A total of 5,936 SBDs was produced during the war. The last SBD rolled off the assembly lines at the Douglas Aircraft plant in El Segundo, California, on 21 July 1944. The Navy placed emphasis on the heavier, faster, and longer-ranged SB2C. From Pearl Harbor through April 1944, SBDs had flown 1,189,473 operational hours, with 25% of all operational hours flown off aircraft carriers being in SBDs. Its battle record shows that in addition to six Japanese carriers, 14 enemy cruisers had been sunk, along with six destroyers, 15 transports or cargo ships, and scores of various lesser craft."Navy's Final SBD Is Built: Type to be Supplanted by SB2C's." Naval Aviation News, 15 September 1944, p. 11.
Medal of Honor recipients Two SBD pilots received the Medal of Honor during World War II, with both during the Battle of the Coral Sea: USN Lt. (j.g.) William E. Hall of Scouting Squadron 2 on was awarded the Medal of Honor for his action during the Battle of the Coral Sea on 7–8 May 1942. On 7 May, Hall participated in the attack that sank the Japanese light carrier Shōhō. The following day, while flying anti-torpedo plane patrol in defense of his carrier, he attacked a formation of Japanese torpedo bombers, shooting down the lead plane and forcing the remaining planes to alter their attack. Shortly afterward, Hall was attacked by several A6M Zeros. Despite being seriously wounded and his SBD heavily damaged in the ensuing dogfight, he claimed two Zeros shot down (though none were lost) and succeeded in landing safely aboard Lexington.