The U.S. Marine Corps’s AH-1Z Viper attack helicopter possess a little-known capability. In addition to attacking ground and sea targets, they’re capable of fighting other helicopters -- and, in a pinch, even fixed-wing warplanes.

Tom Demerly, a writer for The Aviationist, was reminded of this fact during an air show at Marine Corps Air Station Pendleton in California in September 2019.

“The AH-1Z Viper gunship on static display had a conspicuous armament package that drew many comments and questions: a pair of what appeared to be inert AIM-9 Sidewinder air-to-air missiles,” Demerly wrote.

The AIM-9 is an infrared-guided dogfighting missile with a maximum range of up to 22 miles in its latest version.

“It’s a possible configuration,” one of the aircrew explained. “We don’t train with them commonly, mostly for loading practice, but it is a capability we have and we wanted to show it.”

The Viper flier might be overstating the rareness of air-to-air missiles on AH-1s. Photos from as recently as 2019 depict AH-1s carrying Sidewinders while flying from U.S. Navy assault ships sailing the Persian Gulf.

And at least one country actually has deployed AH-1s in the air-to-air role during a major war. “The 1980-1988 Iran-Iraq War witnessed numerous helicopter air-combat engagements,” Marine major R. M. Brady wrote in 1992.

“During this war, Iranian AH-1Js engaged Iraqi MI-8 Hip and MI-24 Hind helicopters. Unclassified sources report that the Iranian AH-1 pilots achieved a 10:1 kill ratio over the Iraqi helicopter   pilots during these engagements. Additionally, Iranian AH-1 and Iraqi fixed-wing aircraft engagements also occurred.”

Brady noted that until the late 1980s the Marine Corps trained its AH-1 pilots in air-to-air tactics, but halted the practice after deciding that the training strained the helicopters’ airframes. He argued for the tactical training to resume. “There must be a renewed emphasis within the Marine Corps and [the U.S. Navy] on the importance of conducting realistic [air-combat maneuvers] training within the AH-1 community.”

Helicopter ACM training did not resume, although American AH-1s still can carry and fire Sidewinders and also could employ their guns and unguided rockets in the air-to-air role.

But absent specific training, it’s unclear how effective the ‘copters would be as dogfighters. “In order to be an effective [air-to-air warfare] platform, the AH-1 must be flown by aircrew that are knowledgeable and proficient in air combat maneuvers,” Brady wrote.

One Marine recently said the AH-1’s air-to-air role could expand, thanks to the introduction of the F-35B stealth fighter.

Capt. Daniel Kelly, an AH-1Z pilot with Marine Light Attack Helicopter Squadron 169 in Okinawa told AIN that the F-35 helps Marine forces to neutralize radar threats, making helicopters more survivable in the aerial escort role.

The escort role involves AH-1s flying alongside transport helicopters and tiltrotors in order to protect them from enemy forces. Those forces could include fixed-wing warplanes, or even enemy helicopters firing air-to-air missiles.

David Axe serves as Defense Editor of the National Interest. He is the author of the graphic novels  War Fix, War Is Boring and Machete Squad.