The G.91 R/4 is a premium Italian jet fighter. It was introduced in Update 1.87 "Locked On" as a pack vehicle purchasable in the Gaijin Store, but was removed from sale after the 2021 May Sale. It later returned for purchase for Golden Eagles in Update "Red Skies".

The R/4 is a variant of the G.91 jet fighter that has been modified for ground attack, allowing it access to a competitive selection of air-to-ground ordnance such as bombs, rockets, and high-explosive air-to-ground missiles. The R/4 also has the option to equip two different types of air-to-air missiles: the IR-tracking AIM-9B Sidewinder missile, or the command-guided AA-20 Nord missile.

The G.91 R/4 is a very nimble fighter with relatively average top speed and fairly good acceleration. Best played as a support fighter, the G.91 R/4 can use its incredible roll and turn rates to quickly get guns on target, as well as to dodge the typically less manoeuvrable fighters that it shares its battle ratings with.

There are few changes between the Pre-serie, R/1, R/3 and the R/4, with exception of the armament, and this guide can be considered universal for all listed aircraft.