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. These Quinjets used a 2x2 symmetrically-mounted modified Pratt & Whitney J48-P-8A Turbojet engines.
Alternate Reality Versions
|On Earth-199999, The quinjet is an advanced aircraft used by S.H.I.E.L.D for transport, and many 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 America and the Black Widow used a quinjet to intercept Loki. Black Widow attempted to line up her target with the quinjet's forward guns, but couldn't get a clear shot. Iron Man then hijacked the quinjet's speaker system to play "Shoot to Thrill" by AC/DC when he flew in to take over the situation personally. However, while transporting 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 used a quinjet to attack the helicarrier and free Loki. The attack was a success and Loki was able to escape in the quinjet. Captain America, Hawkeye and Black Widow, commandeered a quinjet in order to get to New York City to stop the Chitauri invasion. It was shot down by Loki shortly after arrival. 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 Insight helicarriers. One Quinjet was used against Captain America as he tried to escape from the Triskelion. Agent Coulson and his team went into a government facility that had multiple quinjets in order to steal one. He wanted it for the cloaking technology that the craft have to use on the The Bus. 
With the reformation of the Avengers, came the need for the team to have a global mode of transportation, and so they outfitted a newer model with a more spacious interior. It retained the forward miniguns, but had the gunnery position removed to make way for a more centrally mounted pilot's seat. This was called into action in several engagements against Ultron, and even briefly fell into the hands of Ultron, but was lost near Fiji when the Hulk allowed it to carry him clear of the conflict, and its stealth technology masked it even from S.H.I.E.L.D.'s detection.
|Marvel's The Avengers|
|On Earth-8096, 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: Earth's Mightiest Heroes (Animated Series) Season 1 3|
|On Earth-12041, 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.||Avengers Assemble (Animated Series) Season 1 1|
|On Earth-1298, this Quinjet is the last surviving aircraft of the Sentinel attack on Avengers Mansion. It is used by The Defenders.||Mutant X Annual #1999|
|On Earth-BW27, the Quinjet is an Alchemax aircraft used by their Avengers.||Secret Wars 2099 #2|
- 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.