12,7 .50 Frangible Armor Piercing (FAP)


FAP is a type of high-performance, explosive-free, multi-purpose ammunition for fighter planes and fighter-bombers. Each round is armed with a penetrator consisting of individual frangible heavy metal pellets and heavy metal sub-projectiles. After penetrating the target envelope, the heavy metal pellets disintegrate into multiple fragments. As the fragments penetrate deeper into the target interior, the number of fragments increasing, turning into a cascade of heavy metal. This is a highly effective means of neutralizing armoured targets on the ground and in the air. FAP cartridges are designed for air-to-ground and air-to-air engagements. Owing to their special design – and unlike conventional aircraft ammunition – FAP cartridges never result in ricochets as the projectile core disintegrates upon impact.

12,7 .50


Frangible Armor Piercing (FAP)

Thank you for the great pictures.



Nice to see. Usually the FAP projs. are used for AA work and some softer or lightly armored targets.

I understand these are from RUAG now?


A bit more on the subject:



Very interesting round. This round is probably more effective Air-to-Air than the 20mm HE rounds. Tests on the US 20mm HE round showed that it’s effectiveness Air-to-Air was not great. The fragments, except for the nose with the fuse lacked the energy to penetrate the typical jet engine. opening a significant hole, or multiple holes in the hot section of a jet engine is like igniting a very hot cutting torch inside the structure of an aircraft and can often result in the failure of the rotating parts of the turbine which can cause huge damage. In the mid-1970s the AF Armament Lab was looking at this problem and trying to come up with an improved Air-to-Air projectile in 20mm. The effort was dropped, in fact the entire “Improved 20mm program” was dropped because there was so much of the current 20mm HE in the inventory, particularly the War Readiness Munitions, that it would cost alot of money to replace it, and there were higher priority requirements.

This FAP looks like a wonderful solution to this problem, but still there is the issue of the replacement costs.



Lew, then it might be interesting to look at the PELE too. Basically a semi AP with Frag effect without any energetic materials.



Are there many aircraft in service today which would use .50 BMG armament for air-to-air purposes?


Lots of M2/M3 mounted on helicopters.


But unlikely to be against other aircraft.

The 12.7x99 should be more AA then.


General Dynamics still makes a 20mmx102 FAP (although manufactured in collaboration with license from Oerlikon) and was just recently qualified and is in service by Netherlands and Switzerland. For the M61 and M39 20mm cannons.