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Pilots of the very first
airplanes used for military purposes simply fired pistols and rifles from their
open cockpits toward ground targets, and even other airborne targets (airplanes
and balloons). Soon thereafter, machine guns were mounted to the upper wing
and/or wing struts of biplanes. Once synchronization mechanisms were developed
to permit firing through the propeller, guns were mounted directly in front of
the cockpit, on the fuselage, giving the pilot the advantage of directly
sighting for firing. When the target is large and/or the size of the ammunition
is large enough to inflict significant damage regardless of where it hits, then
being able to draw a visual bead on the sweet spot is not as important. Next
came separate gunners who were stationed above, below, in front of, and behind
the pilot, depending on the design and size of the ship. The gunner had freedom
of movement to move the gun around relative to the way the airplane was
pointing, and he was not encumbered with having to fly the plane at the same
time. As the speed of airplanes increased and hardening against gunfire
advanced, larger projectiles and the guns which fired them were required, and
soon they were too heavy for the gunner to support and manipulate, so articulate
mounts were developed. By the time World War II came around, aircraft, armament,
and mechanics were sophisticated enough to facilitate power-assisted guns that
easily move the hardware according to the gunner's command. That relieved not
just the weight of the gun, but also compensated for the multiplied effort
needed to counter G-forces which could cause unbearable effort on the part of
the gunner. Negative G's were just as bad. A wildly maneuvering airplane
undergoes constant changes in G forces, which are difficult enough for the human
passenger to accommodate without needing to also facilitate the effects on the
guns. Master artist Douglas Rolfe provided this group of drawings representing
the evolution of turrets. It appeared in a 1948 issue of Air Trails
magazine.
Air Progress: Development of Gun Turrets
 By Douglas Rolfe
The very first military airplanes had no provisions for armament, except of the
most primitive kind. During the early days of World War I, when the average top
speed of even the fastest planes was not more than 80 mph it was possible to employ
primitive fixed gun mounts, but as the war progressed and. air speeds mounted the
fixed mount was found inadequate. This led to the invention of the Scarff ring,
a manually operated rotating mount which permitted the gunner to swing his guns
in a complete circle and elevate or depress them with the minimum of exertion.
As air speeds again mounted it was found that open gun mounts were as useless
as the old fixed mounts. Slip-stream pressure alone made it difficult for the gunner
to man his guns with accuracy. This difficulty led to the development of enclosed
mounts, many of which were merely blisters with manually operated guns such as the
Armstrong Whitworth turret.
In the old days open sights were deemed adequate. Then appeared the ring-bead
sight and, later, a sight which was supposed to provide compensation for wind and
drift. The reflector sight, developed during the last war, is still generally employed
but the remarkable increase in air speeds since the war suggests that this form
of sight is obsolescent.
Typical Scarff Type Ring
Basic element of most early manually operated gun turrets.
Frazer-Nash Semi-Enclosed Armored Turret
This hydraulically operated turret appeared in 1936. It afforded the gunner some
protection against the slipstream and, in lesser degree, from enemy gunfire.
World's First Genuine Power-Operated Turret
Produced in 1934 the Bolton Paul Turret, shown here mounted in the nose of a
Bolton Paul Overstrand Medium Bomber, had pneumatically operated turning mechanism.
Early Type Bubble Turret
This single-gun manually operated Armstrong Whitworth Turret was actually little
more than a semi-enclosed modification of the old Scarff Ring. It was obsolete long
before 1939.
Improved Twin-Gun Bubble Type Top Turret
Completely mechanized turrets of this type were first introduced during World
War 2. Electro-hydraulically operated, with servo-fed ammunition belts and reflector
sights, they revolutionized turret design.
Typical U.S. Type Twin-Gun Turret Assembly
Top Turrets such as this protected our attack planes and medium bombers from
enemy attack in last war.
B-29 Remotely Controlled Turret Installation
General arrangement of the forward upper and lower gun turrets which are aimed,
trained, and fired by remote control.
Typical British Type Multi-Gun Tail Turret
Formidable batteries of machine guns mounted in this manner put a sting into
the tail of the heavy bombers used by the Royal Air force over Germany.
Posted May 11, 2024
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