Douglas SBD-6 Dauntless

The Douglas SBD Dauntless was one of the truly great aircraft of World War II. It played a major role throughout the Pacific. On June 4, 1942, during the Battle of Midway, SBDs destroyed four Japanese carriers, dramatically altering the course of the war.

The SBD's design was based on the Northrop BT-1, but with engine and structural changes. Production orders were placed in April 1939, with all SBD-1s going to U.S. Marine Corps units. Subsequent models were sent to Navy squadrons, with each succeeding model carrying such improvements as increased fuel capacity, illuminated gunsights, and armor plates for the crew. England, New Zealand, and France also used SBDs. The SBD-6 was the last production model, with 450 built.

This SBD-6 carries the markings of VS-51 (Navy scout squadron), which operated in the Pacific during World War II.

The Douglas SBD Dauntless played one of the most significant roles in the course of World War II. Although considered obsolete and scheduled for replacement before the war began, the SBD would live up to the nickname given to it by its crews - Slow But Deadly (a play on its official designation). Serving throughout the war, Dauntlesses would sink more than 300,000 tons of enemy shipping, including at least 18 warships, ranging from submarines to battleships. During 1942, SBDs were the primary weapon in the U.S. war effort in the Pacific, almost single-handedly sinking six enemy carriers.

Navy experience with dive bombing went back to the early years of naval aviation. United States Marine Corps pilots had experimented with the technique as early as 1919 although it was not known by that name at the time. With the commissioning of the first carrier, the USS Langley, the Navy realized there would be limitations to the size of aircraft used at sea. Carrier planes could not hope to carry the same bomb load as shore-based aircraft, so they needed to be able to deliver each bomb as accurately as possible. Dive bombing was the answer. The technique gained official status in 1926 when the Navy included it in the fleet exercises. Accidents involving the bomb hitting the propeller or wheels on release, however, nearly ended its use. A solution was found in a bomb fork, which swung the bomb clear of the propeller arc. Approval followed in 1931.

In 1934 the Bureau of Aeronautics held a design competition for a new generation of carrier aircraft. The Navy wished to replace its four main types - fighter, scout-bomber, torpedo bomber, and dive bomber - with modern all-metal monoplane aircraft. Designs by Vought, Brewster, and Northrop were chosen for further development in the dive bomber category. Brewster lacked the facilities to meet the Navy's needs and the Vought design did not have the necessary performance, although 50 would later be ordered as the SB2U Vindicator.

The Northrop entry bore a family resemblance to the firm's Alpha series of mailplane aircraft. Chief engineer Ed Heinemann's racy low-wing monoplane design incorporated many of the revolutionary construction techniques used in the earlier aircraft. Unlike the Vought entry, the XBT-1 (as the Northrop aircraft was designated), in an effort to save weight, did not include folding wings. Split dive flaps on the trailing edge of the wing, which were perforated, eliminated tail buffeting and permitted a steeper diving angle. The Navy approved the design and ordered 54 production models designated as BT-1s.

The BT-1, however, had stability problems and with an 825 horsepower Pratt & Whitney engine, was underpowered. A second prototype, the XBT-2, incorporated the new 1,000 horsepower Wright R-1820-32 engine, which boosted the BT-1's top speed of 212 mph by 35 mph. The addition of a modified rudder corrected poor lateral stability. A fully retractable landing gear was also included on the new prototype. The new design featured improved stability and low-speed control.

During the development of the XBT-2, Douglas took over the Northrop contract. Many Northrop employees, including engineer Ed Heinemann, moved over with the project, and in 1938, Northrop sold his El Segundo, California factory to Douglas. With the switch in manufacturers the XBT-2 became the XSBD-1 (for Experimental Scout-Bomber Douglas -1). After some more minor modifications, the Navy ordered 144 SBDs in April 1939. In common with other Douglas aircraft whose names began with the letter "D", the SBD was named the Dauntless.

Although the Navy had placed an order, it did not consider the SBD-1 to be fully combat-ready. The main problem was a lack of fuel capacity, which limited the range of the Dauntless. With the amount of time spent forming up and landing on a carrier, fuel capacity was considered to be critical. Douglas agreed to address the problem, beginning with the 58th production model. The Navy agreed to accept the first 57 SBD-1s without modification and decided that the Marines, who mostly operated from land bases, could use these aircraft. The Marines, therefore, received the first Dauntlesses in June of 1940.

The remaining 87 aircraft of the original contract were delivered as SBD-2s. While the modifications of this version did not solve all the problems, they did improve on the lack of range. In this model, the two small 15-gallon auxiliary fuel tanks located in the wing center section of the SBD-1 were replaced with two 65-gallon tanks in the outer wings. Fuel capacity was increased from 210 to 310 gallons and range increased to 1,200 miles. The SBD-2 also had an autopilot for the long over-water flights that were now possible. The increased weight, however, hurt performance and often one of the two .50 caliber fuselage-mounted guns would be removed to compensate. Deliveries of the SBD-2 to VS-2 and VB-2 on board the USS Lexington began in November 1940, with USS Enterprises's VS-6 and VB-6 following shortly.

The initial two models of the Dauntless would see the first combat in the Pacific on 7 December 1941, during the attack on Pearl Harbor. Marine Air Group (MAG) 11 - equipped with the SBD-1 - was caught on the ground and all aircraft were either damaged or destroyed by the Japanese. At the same time, 18 Navy SBD-2s, launched from the Enterprise, which was returning to Hawaii from Wake Island, arrived just as the Japanese were attacking. Seven Dauntlesses were shot down or crash-landed. Two Japanese aircraft were claimed shot down by the Dauntlesses. Three days later the SBD gained the distinction of destroying the first Japanese warship of World War II when Lt Dickinson of VS-6 sank the Imperial Japanese submarine I-70 off of Hawaii.

As 1942 began, it was obvious that any retaliation for Pearl Harbor would have to come from the carrier forces, which had been at sea during the attack and had therefore avoided destruction. The first action took the form of hit-and-run raids by the carriers Enterprise, Lexington, and Yorktown, against remote Japanese positions in the spring of 1942. While these raids caused little damage, they served notice that the U. S. Navy was still fighting. Dauntlesses were heavily involved and attacked many ships and shore installations in these raids. One of the most famous strikes of this period was the Doolittle raid on Tokyo. An SBD reported a Japanese picket boat ahead of the task force. The Dauntless crew also reported that the boat had probably sighted them, thus precipitating the early launch of Doolittle's B-25 bombers.

Deliveries of the new SBD-3 began in March 1941, and were stepped up after the attack on Pearl Harbor, so that this was the main type to be used throughout the major battles of 1942. The SBD-3 brought the Dauntless up to full combat standards. Self-sealing wing tanks, crew armor, and an armored windscreen were all introduced. Experience gained in the Battle of the Coral Sea prompted the introduction of twin .30 caliber machine guns in the rear cockpit, thus increasing firepower. They were made standard in mid-production and earlier examples of the SBD-3 were retrofitted with the guns in the field. The added weight of these improvements was offset to a certain extent by the use of alclad to replace the dural skin of the earlier models, and the removal of the flotation equipment that was standard on the SBD-2. Maximum speed fell by a small margin to 250 mph, earning this model the tongue-in-cheek nickname of " The Speedy Three". Service ceiling, however, improved from 26,000 to 27,100 ft.

In May 1942, the U.S. faced its first major operation against the Japanese fleet at the Battle of the Coral Sea. The battle resulted when Admiral Nimitz sent Yorktown and Lexington to block the Japanese thrust towards Australia. In this, the world's first carrier duel in which the opposing ships never came within sight of each other, Dauntlesses were responsible for sinking the Japanese small carrier Shoho. Despite the fact that the Japanese sank the larger U.S. fleet carrier Lexington, the battle was a strategic victory for the Americans because it stopped the Japanese move to the south. In less than a month's time, Dauntlesses would improve on their Coral Sea performance.

With the failure of the southern expedition, the Japanese decided to strike at the U.S. base on Midway Island. The plan was to gain a base from where they could threaten the Hawaiian Islands and thus draw the remaining U.S. carriers out to be destroyed in a major fleet engagement. The U.S. Navy had an advantage in that they had broken the Japanese code and knew the attack was coming. Also, the Japanese did not realize that Yorktown, which had been damaged (and believed sunk) at Coral Sea, had been hastily repaired and was able to join Enterprise and Hornet at Midway. The three U.S. carriers carried 112 Dauntlesses. Most were the latest model, but a few SBD-1s and -2s were also aboard. While the Japanese had a much larger fleet, the sides were more evenly matched in the crucial area of airpower. The Japanese had four aircraft carriers, and the U.S. had three carriers and the land-based aircraft at Midway, which included 19 SBD-2s.

By June 3, the American carriers were ready and had spotted the enemy troop transports. The next day the Japanese opened the battle with a strike on Midway. Meanwhile, a PBY Catalina had spotted the Japanese fleet and the U.S. carriers began to launch their aircraft. Because of the varying launch times and speeds of the different aircraft, the TBD torpedo planes were the first to attack the Japanese carriers. The slow Devastators were easy targets for the Japanese fighters and were soon beaten back with no damage to the carriers. Because of the uncoordinated nature of the attack, the SBD squadrons had trouble finding the carriers. The Hornet SBD's never found the carriers. Lieutenant Commander Wade McClusky, the Commander of the Enterprise's Air Group, however, made a navigational guess that brought his VS-6 and VB-6 right over the Japanese carriers. The attacking TBDs had drawn down the Japanese fighter screen and the Dauntlesses found the targets wide open. Japanese indecision as to whether to launch further strikes on the island or to attack the recently discovered American carriers, left bombs and torpedoes, along with aviation fuel, scattered on the carriers' decks. At the same time as McClusky's group attacked, VB-3 from Yorktown arrived. The combined onslaught rained 39 bombs on three Japanese carriers in three to four minutes, and 11 direct hits mortally damaged the Akagi, Kaga and Soryu. The fourth carrier, Hiryu, was located later and was also sunk by Dauntlesses. Japan lost four carriers and many of its experienced aviators for the loss of 35 Dauntlesses from the six Navy and one Marine SBD squadrons engaged. The SBD had stopped the Japanese and allowed the U.S. to fight on an equal footing in the Pacific.

The Dauntless would also play a significant part in the first major American offensive, the fight for Guadalcanal. Marine SBDs based on the island attacked Japanese ships, which were known as the "Tokyo Express", that were attempting to reinforce the island. Ship-based SBDs also participated in the eastern Solomon's campaign, of which Guadalcanal was a part, and sank another Japanese carrier.

While the SBD is most often associated with the Pacific theater of operations, it did serve in a limited capacity in the Atlantic. In November 1942, Dauntlesses flew from the carrier Ranger and the escort carriers Sangamon and Santee in support of Operation TORCH, the invasion of North Africa. In contrast with the naval actions of the Pacific, SBD attacks were mostly against ground targets in support of the Allied landings. They were, however, called upon to attack seven Vichy French cruisers that set out to attack the Allied troopships. On November 10, nine SBDs from the Ranger sank the moored battleship Jean Bart which had been firing on the invasion fleet. With the sinking of the Japanese battleship Hiei in the Pacific three days earlier, this was the second enemy battleship sunk by Dauntlesses within one week.

SBDs from Santee also conducted anti-submarine patrols in the Atlantic during 1943, but the TBM Avenger was better suited and was used more often for this type of work. Marine Dauntlesses operated in the patrol and scouting role from the Virgin Islands until mid 1944. The last offensive mission for the Dauntless in the Atlantic was an attack on enemy shipping in Norway called Operation LEADER. SBDs from the carrier Ranger attacked several ships in Bodo harbor and roadstead. They sank two ships, shared in the destruction of two more, and damaged a further two.

Douglas continued to modify the Dauntless throughout the war in an attempt to improve performance. The SBD-4 was introduced in late 1942. It had an improved 24-volt electrical system that allowed for the installation of radar. It also featured a Hamilton-Standard Hydromatic propeller. But, at 245 mph maximum speed, this was also the slowest version. Early in 1943 the SBD-5, with a larger engine, started to enter squadron service. Two additions that increased bombing accuracy were the replacement of the telescopic sight of the early models with a reflector sight and a heated windscreen, which overcame the fogging that had been common in the dive run. Radar was also more commonly seen on this model. The additional weight of the extra equipment, however, largely cancelled out the increased horsepower.

The SBD-5 was the most produced variant of the Dauntless and served throughout the battles of 1943. The last version of the Dauntless, the SBD-6 featured a larger engine, which raised top speed to 262 mph, and service ceiling to 28,600 ft. In all other ways, however, it differed little from the previous model. By the time it entered production, the Helldiver was replacing the Dauntless in the fleet and the SBD-6 remained, for the most part, stateside.

By June 1943 the U.S. Navy had four new, large, Essex-class CV carriers. The Helldiver was supposed to be the dive-bomber assigned to the new carriers, but in the summer of 1943 it was not ready for combat. The Dauntless therefore soldiered on. Its role on the new carriers changed however. The new CVs could carry 100 airplanes, compared to 80 on the older carriers, and the scout squadrons were eliminated. The difference in airplanes was made up by an increase in the numbers of fighters. Scout duties were now taken over by the Hellcats and Avengers, both of which had long range capabilities. From then on, Dauntlesses would serve almost exclusively as strike aircraft. SBDs continued to fly throughout 1943 and not until late in the year did the SB2C Helldiver finally enter service. Many navy pilots did not see the Helldiver as much of an improvement over the Dauntless. Pilots preferred the SBD's more responsive controls which made it an easy plane to fly when lightly loaded. The Douglas aircraft also required less maintenance hours than did the Curtiss.

Despite the introduction of the Helldiver, Dauntlesses continued in Navy service until July 1944 when they participated in their last mission during an attack on Guam. The Marines continued to use them in the Philippines campaign. By the end of World War II, most Dauntlesses had been relegated to the training and utility roles. A few Marine SBDs, however, were still at work neutralizing bypassed garrisons in the Solomons until the end of the war.

The Dauntless was not only used by the U.S. Navy, but also by the Army. The success of the German dive-bombers during the early years of the war in Europe convinced some army leaders of the need for a U.S. version. Limited experience with this type of aircraft and no time to develop a new design, however, dictated that the United States Army Air Force (USAAF) place orders for the Navy's SBD. In Army service it was know as the A-24 Banshee. The main differences with the Dauntless were the lack of a tailhook, and a larger pneumatic tailwheel. The Banshee was delivered as the A-24, A-24A, and A-24B, which were equivalent to the SBD-3, -4, and -5. The idea of dive-bombing was not widely supported in the USAAF, however, and the Banshee was not used extensively.

In addition to the United States, New Zealand (in the Solomons) and the Free French (in Europe) also flew SBDs. As late as 1949 the French were using SBDs to carry out attacks on Communist terrorists in Indo-China. Mexico flew Banshees, which it had received for patrol missions in the Gulf of Mexico during World War II, as border patrol planes until 1959.

NASM's Dauntless, Bureau Number 54605, was the sixth SBD-6 model produced. It was accepted by the U.S. Navy on March 30, 1944, and delivered a week later on April 7. It spent its entire operational career at Naval Air Station Patuxent River, Maryland. From August to September 1944 it was used for tactical tests. From October 1944 to April 1948 it was used for flight tests. In May 1948 it was put in storage at NAS Weeksville, North Carolina. Stricken from Navy service June 30, 1948, it was earmarked for the national collection. This was perhaps the last SBD to serve with the U.S. Navy. Dauntless 54605 was accessioned by the Smithsonian in 1961 and restored in 1975. It was installed in the Sea-Air Gallery in the new museum on the National Mall in 1976, where it can be seen today.