Q4. When used on F-14 aircraft, where is the M61A1
gun system mounted?
Q5. What is the maximum capacity of the gun system
when used on the F-14 aircraft?
MAINTENANCE AND TESTING
LEARNING OBJECTIVE: Identify main-
tenance and testing procedures at the
organizational and intermediate levels.
The maintenance and testing responsibilities of an
M61A1 gun installation are distributed evenly between
the organizational and intermediate levels of
maintenance. The basic responsibilities of these two
levels of maintenance are discussed in the following
paragraphs.
ORGANIZATIONAL MAINTENANCE
Organizational maintenance includes servicing
(loading and unloading), preflight, postflight, minor
periodic maintenance, malfunction troubleshooting,
and removal and installation of components on the
aircraft. Also, maintenance of the aircraft system and
controls must be included in the AO’s organizational
responsibilities.
The gun firing record or log is kept at this level. The
cumulative total of rounds fired is the basis for most of
the maintenance. The number of rounds fired per firing
flight is obtained from a counter located within the
aircraft. For record accuracy, each time the gun
installation is loaded, the counter must be reset (usually
to zero) according to the instructions applicable to the
aircraft. The two primary tasks that depend upon the
round interval (rounds fired) are (1) torquing the two
forward front track bolts (30,000 rounds), and (2)
changing the breech-bolt assemblies (15,000 rounds).
Organizational responsibilities are not included
in NAVAIR 11-95M61A1-1 or the NAVAIR
11-95M6lA1-2. Organizational responsibilities are
outlined in MRCs, aircraft MIMs, and aircraft loading
manuals.
If a component is being removed for sudden
stoppage (jam) maintenance, be careful and take extra
precautions. Loose propellant powder from ruptured
cartridge cases may be scattered about the gun
compartment. This creates an extremely hazardous
situation. The loose powder must be removed in a
RADHAZ-free environment before you begin to
remove a component.
INTERMEDIATE MAINTENANCE
Intermediate maintenance responsibilities are tasks
associated with repair or replacement of unserviceable
or damaged assemblies, components, or parts of the gun
installation that do not require the special maintenance
facilities of an overhaul depot. When a gun reaches a
round interval of 120,000 rounds fired or requires major
repair or alteration, it is sent to a depot-level
maintenance activity. The ammunition handling and
gun drive system maintenance procedures are identical
at both the intermediate- and depot-maintenance levels
(with one exception, the depot level removes bearings);
therefore, such maintenance is generally performed at
the intermediate level. Intermediate maintenance may
be divided into two categories—scheduled and
unscheduled.
Scheduled maintenance includes inspecting,
disassembling, replacing parts, lubricating, assembling,
and functionally checking components based on the
round interval specified in technical manuals.
Scheduled gun maintenance begins at 15,000 rounds
and proceeds through various interval states for
different parts replacement up to the 120,000-round
overhaul interval. Scheduled maintenance for the
handling and drive system is set at an interval of 30,000
rounds.
REVIEW NUMBER 6
Q1. The breech bolts are changed out when what
number of rounds have been fired from the
M61A1 gun system?
Q2. What is the overhaul interval for the M61A1
gun ?
Q3. At what interval should scheduled maintenance
for the handling and drive system be done?
SAFETY PRECAUTIONS
LEARNING OBJECTIVE: Identify safety
precautions to follow when working with the
M61A1 gun.
The weapons systems described in this chapter are
safe systems. Live rounds are isolated from the firing
circuits except when the gun system is deliberately
being fired. The gun system is RADHAZ safe and
completely shielded from radiation fields. The gun is
charged and cleared in flight, so the aircraft can takeoff
and land without live rounds in the firing position.
Although the sole purpose of all ordnance is to destroy
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