Hi Akitaken and welcome,:thumbup:
1.
Verify that the P80 Outer Wing, P1 Inner Wing and P2 Engine Mounted Armament Circuit Breakers are IN
(
2.
Arm Machineguns and Inner Wing Cannons by setting the MASTER ARM SAFETY I switch ON (UP)
3.
Arm Outer Wing Cannons by setting the MASTER ARM SAFETY II switch ON (UP)
4.
Flip the Cannon Safety Cover UP (LSHIFT+SPACE)
5.
Press the “MG131/151 Trigger A” button (SPACE) to fire your MG131 Machineguns and Inner Wing MG151
Cannons. Press the “MG151 Trigger B1” button (RALT+SPACE) to fire Outer Wing MG151 Cannons. Hold both
triggers at once to fire all machineguns and cannons at once.
This is from the chucks guide series that he makes.He is great and his guides have helped many a virtual aviator.
A link to all his guides
https://forums.eagle.ru/showthread.php?t=135765
Best of luck to you and if you have any more trouble just post a msg here and i will answer any questions you have :pilotfly: