GAU-21 Flashcards
-1 PDF 1272
What does “in battery” mean?
Bolt is in forward position
-1 PDF 1272
What does it say regarding using checklists during weapons emergencies? NOTE
Due to the nature of weapon emergencies, the use of checklists is not always practical. Perform steps 1-4 immediately.
-1 Malfunctions
What are the immediate actions for malfunctions? GAU - 21
- Notify Crew “_____ gun bent”
- Gun trained on target
- Forward Fire Switch OFF
- Charge Gun
-1 PDF 1271
Safe vs Safe and Clear
Safe= weapon does not render a dangerous condition
Safe and Clear= weapon has been visually checked to be clear of ammunition and does not render a dangerous condition
-1 PDF 1271
Weapons System Malfunction General
The operators first concern will be…
Safing the weapon
-1 PDF 1272
Misfire Definition
Complete failure of the weapon to fire.
-1 PDF 1272
Hang fire Definition
A delay in the function of the propelling charge. A hang fire cannot be distinguished immediately from a misfire and therein lies the principal danger.
-1 PDF 1272
Cook-Off Definition
Firing of the explosive components of a round due to overheating of the weapon and not due to actuating the firing mechanism.
-1 PDF 1272
Runaway Gun Definition
Failure of the weapon to cease firing when the triggers are released.
-1 Major Components
PDF 906
Auxiliary return springs assembly
Back plate assembly
Barrel & barrel extension
Barrel buffer assembly
Barrel jacket assembly
Bolt assembly
Feed cover assembly
Receiver assembly
Trigger assembly
Section IV GAU-21 CAUTION
Window closed
Ensure weapon is locked forward to prevent damage to gunners window
SECTION IV GAU-21 CAUTION
Stepping
Stepping on the ammunition can cover or the medium external connection assembly may cause damage
SECTION IV GAU-21 CAUTION
Ammo can front fairing
Lifting the ammunition can cover by the front fairing may cause damage
SECTION IV GAU-21 CAUTION
Probe
When probe is extended, round trajectory can be less than 6 inches from probe
SECTION IV GAU-21 NOTE
Vox
Firing weapons may actuate the pilots or copilots intercoms system when using VOX
SECTION IV GAU-21 NOTE
100 knots
Significant force is required to move all weapons forward of the 3-9 line when traveling at airspeeds above 100 kts
SECTION IV GAU-21 NOTE
When weapons aren’t being used
They should be stowed forward down position during taxi, takeoff, and landing (unless threat condition prohibits stowing)
SECTION IV GAU-21 CAUTION
Ammo chute
Failure to connect the ammunition chute to the gun can result in the loss of ammunition overboard and/or damage to airframe and weapon system components
SECTION IV GAU-21 CAUTION
Barrel cooling, what is this caution protecting?
Allow the barrel to cool to ambient (approx 2 min 30 sec) after firing a sustained long burst of approximately 100 rounds or many short bursts in quick succession. cooling to ambient varies depending on the environment conditions.
It’s to preclude damage to the gun barrels
Burst Limitations Table (Only when Static aka Hover Fire)
11W-13-21-2 PDF 60
1.5 sec burst = 30 sec cooling
3 sec burst = 1 min cooling
6 sec burst = 2 min 30 sec cooling
WARNING What is mandatory after firing 600 rounds?
11W-13-21-2 PDF 60
Complete cooling of the barrel to avoid injury to personnel and ensure optimal performance of the weapon.
Major Assemblies (salute)
11W-13-21-2 PDF 62
Barrel Assembly
Receiver Assembly
Bolt Assembly
Barrel Buffer Assembly
Feed Cover Assembly
Back Plate Assembly
Auxiliary Return Springs Assembly
Trigger Assembly
What is the purpose of the barrel extension assembly?
11W-13-21-2 PDF 63
Forms the link between the barrel and the barrel buffer assembly.
What ensures correct connection with the barrel extension and barrel buffer assembly?
11W-13-21-2 PDF 63
The rear shank of the barrel extension.
Where is the breech lock?
11W-13-21-2 PDF 63
It’s inserted into the rear of the barrel extension subassembly.
What is significant about the breech lock movement?
11W-13-21-2 PDF 63
It is secured to have restricted vertical movement by means of the breech lock pin. This allows it to travel along the breech long cam upward.
What is the receiver assembly’s purpose?
11W-13-21-2 PDF 64
Support, protect, and house various assemblies.
What piece has the bent metal piece we check on preflight it ensure that it won’t block links?
11W-13-21-2 PDF 64
The link guide adapter assembly.
Where is the breech lock cam located?
11W-13-21-2 PDF 65
The bottom of the receiver assembly.
What guides the extractor assembly? Where is it located?
11W-13-21-2 PDF 65
Extractor Switch
It’s located on the inner left hand side plate of the receiver assembly.