Dive bombers, as the name
implies, were aircraft
specializing in delivering bombs
using a diving attack. By flying along a steep trajectory that closely
matched that of the bomb, the dive bomber eliminated much of the error
in aim in the direction of approach.
The best naval dive bombers in the Pacific War
could maintain a dive angle of perhaps 70 degrees. A dive this steep
could easily build up enough velocity for the aircraft to become
impossible to control: As the speed of the air flow across some control
surfaces approached the speed of sound, the control surfaces became
useless. To avoid this difficulty, and to ensure that the aircraft
could pull out after dropping its weapon from an altitude low enough
for accurate bombing, dive bombers were generally equipped with some
form of dive brake. This usually took the form of a special set of
flaps that could be extended perpendicular to the air flow to create
considerable wind resistance and reduce the terminal velocity of the
aircraft to an acceptable value. In addition, the wings had to be very
strong to endure the stresses encountered during the pullout maneuver.
Although dive bombing was originally developed as a means of accurate delivery, the attack profile of a dive bomber also posed difficulties for antiaircraft defenses. Once committed to its dive, a dive bomber was almost immune to fighter attack, since fighters had great difficulty matching such a steep dive and had no dive brakes to prevent them overshooting their target. Heavy antiaircraft shells with timed or hydrostatic fuses were almost useless because of the extreme difficulty of correctly estimating such a rapidly changing range to target. On the other hand, dive bombers were somewhat vulnerable to light antiaircraft fire, though the rapid pullout maneuver gave them some protection once they had released their bombs.
Most dive bombers carried a bomb weighing perhaps
half a ton. Once this was released, many dive bombers were
theoretically nimble enough to act as fighters against heavier
aircraft, such as torpedo
bombers. A number of SBD
Dauntless dive bombers were employed in this manner against B5N Kate torpedo bombers during the Battle of the Coral Sea, with
limited success.
The use of dive bombers against land targets was much less successful than their use against shipping. Ships are very valuable targets, and a loss rate considered acceptable in an antishipping role was unacceptable in a ground support role.
Curiously, a number of aircraft not normally
thought of as dive bombers were pressed into the role, sometimes in the
design stage, and sometimes in the field. We list only dedicated dive
bomber designs below.
References
The Pacific War Online Encyclopedia (c) 2007 by Kent G. Budge. Index