Fighter Combat - Tactics and Maneuvering

2 FIGHTER WEAPONS
although fixed to the aircraft, may be aimed up, down, and from side to side
by the operator to cover a certain field of fire, which may be in any
direction relative to the aircraft. Such guns may be manually operated or
installed in power turrets.
Fixed, forward-firing guns have many advantages for small, maneuverable
fighters. Their installation is generally lighter and produces less drag,
so they have less negative impact on performance. Flexible guns usually
require a dedicated operator in addition to the pilot, which further adds to
aircraft size and weight. Maneuvering relative to another aircraft is also
much simpler when the opponent can be kept in front of the attacker,
which essentially requires a forward field of fire. For these and other
reasons, fixed forward-firing guns have been found to be superior for small,
offensive aircraft (fighters), while flexible guns are generally preferred for
the defense of larger, less maneuverable aircraft.
By trial and error, fighter armament in World War I progressed from
personal side arms to flexible machine guns and, eventually, to fixed
machine guns. The standard fighter at the end of this conflict had two
.30-cal-class fixed forward-firing machine guns, which often were
equipped with synchronizers to allow fire through the propeller disc.
The tremendous progress in aircraft performance during the 1920s and
1930s was in large measure the result of the intense interest generated by
the many international speed competitions of those years. Aircraft
structural methods were also revolutionized, as essentially all-metal construction
became standard. These developments, as well as the lessons of
World War I on the value of firepower, led to significantly increased fighter
armament by the outbreak of World War II.
The reasoning behind these developments is fairly clear. First, increased
aircraft performance allowed the weight of greater armament to be carried.
Second, designers recognized that the higher closure rates resulting from
faster aircraft speeds would, in general, lead to shorter firing times, so more
destructive power was necessary in a shorter period of time. Third, metal
aircraft, particularly the bombers, were much tougher targets, and increased
performance enabled the planes to carry additional armor that
could be used to protect vital areas of the aircraft (armor for World War I
fighters sometimes was an iron stove lid in the pilot's seat).
These developments created a need for greater firepower, which could
be achieved by more guns, larger projectiles, higher rates of fire, greater
muzzle velocities, or explosive bullets. Some pairs of these factors, however,
are related in such a way that neither member of the pair can be
increased independently. Probably the most important of these relationships
is that between projectile weight and rate of fire. In general, the
greater the weight of the shell (including bullet, charge, and casing), the
slower the rate of fire, owing primarily to the inertia of the heavier moving
parts required to handle this ammunition. Obviously, depending on the
gun technology at a given time, there should be an optimum balance
between these two factors. As guns and ammunition are made lighter for a
given projectile weight, the optimum balance shifts toward heavier bul-