Used primarily by the Avengers for transportation to various locations, the quinjet is first designed by the Wakanda Design Group, headed by Black Panther, T'Challa. Each one is equipped with VTOL capability and turbojet engines. A quinjet can reach Mach 2.1. Two highly specialized ultra-large Quinjets were used to transport various superheros through space during the Infinity Crusade.
When the New Avengers were formed, Iron Man reveals that he has three new-model Quinjets that had been in beta testing when the Avengers disbanded. One was destroyed on their first outing to the Savage Land.
Marvel Cinematic Universe (Earth-199999)
The Quinjet is an advanced aircraft used by S.H.I.E.L.D for transport. The Quinjets were kept on board the Helicarrier. A Quinjet was used as the transport that brought Captain America and Agent Coulson aboard the Helicarrier.
In Stuttgart, Germany Captain American and the Black Widow used a jet to intercept Loki. Black Widow attempted to take Loki out with the jet's forward turret. Iron Man later hijacked the Quinjet's speaker system to play "Shoot to Thrill" by AC/DC. However while escorting Loki back to the carrier the Quinjet was intercepted by Thor, who managed to force his way inside and took Loki.
The brainwashed Hawkeye and a team of mercenaries use a Quinjet to attack the Helicarrier and free Loki. The attack was a success and Loki was able to escape in the Jet. Captain America, Hawkeye and Black Widow, hijack a jet in order to get to New York City to stop the Chitauri invasion. The jet however is shot down by Loki.Project Insight, an initiative created to monitor worldwide activity and provide a pre-emptive strike against global threats before they could escalate, a new series of Quinjets with heavier weapons capabilities were created to serve on the new Helicarriers. One Quinjet was used against Captain America as he tried to escape from the Triskelion. 
The Avengers: Earth's Mightiest Heroes (Earth-8096)
In this universe, the Quinjet is presented by Tony Stark as soon as the Avengers formed, stating that "This is a fully functional hangar with two prototype high-speed aerial shuttles. The Quinjets. Weapons, shields, and an air speed of Mach-8, for those of us who can't fly. But they can go into space too".
Avengers Assemble (Earth-TRN123)
In this universe, the Quinjet was an advanced aircraft used primarily by the Avengers for transportation purposes before it was destroyed by M.O.D.O.K. In the early days, the Avengers used the Quinjet on various field mission, one of them during a battle with Molecule Man. The Quinjet made its last service when the re-assembled Avengers used it to get to Hydra's Artic base where it was eventually shot down by enemy anti-air missile defense sentries.It was replaced by the Aven-Jet Prime. 
Mutant X (Earth-1298)
- In Fantastic Four #243, the Quinjet Captain America uses is a open air/topless version that appears to resemble the Champscraft model.
- Similarly, the Quinjet has been modified and updated numerous times over the years. For example, to increase it's speed the Quinjet was once harnessed to Thor's hammer . Captain America also modifed a Quinjet to some unique specifications and referred to it as "Flag Ship One". Quinjet have also been modified for space and sub-space travel.
- Quinjets are infamous for being destroyed soon after they appear.
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