UD4L Cheyenne

The UD4L Cheyenne is a fictional dropship and tactical transport used by the United States Colonial Marines in the film Aliens. It has become an influential fictional vehicle, inspiring similar craft in later films and video games, such as the Republic Attack Gunship in Star Wars Episode II: Attack of the Clones and the DC-77 Pelican from the Halo video game series.

Description
Designed to transport personnel through any atmosphere and land on a planet's surface, the UD4L is similar in theory to a military helicopter. It also appears to act as a gunship by a nose-mounted gatling gun and deploying weapons pods which open for aerial attacks; something used as feature for most of James Cameron's futuristic spacecraft. The principal airframe is described in the Aliens: Colonial Marines Technical Manual, as being constructed of a superplastic-formed diffusion-bonded metal matrix composite. With what is similar to a CH-47 Chinook's rear-ramp, but forward facing, there is a ramp that encloses a 103.6² internal cargo hold, which harbors the M577 Armored Personnel Carrier, a land-based transport, used with similar tactics to the real-world military's Armored Personnel Carriers.

Concept and design
Concept artists were asked to include subliminal acknowledgments to the Vietnam War, due to the influence the War had on the film's story. The AH-56 Cheyenne's look had supplemented the overall process of designing. Because of its influence on the structure, its name was attributed to the UD4L. The AH-1 Cobra used in Vietnam served as a partial inspiration for the design, particularly the cockpit. The use of a gatling gun was inspired by the GAU-8 Avenger, used on the USAF A-10 Thunderbolt II, alongside the F-4 Phantom II's body, tail and enigine vents; whice served as a cosmetic element of the of the UD4L.

Syd Mead and Ron Cobb both designed numerous versions of the UD4L, but James Cameron ultimately built his own miniature out of AH-64 Apache helicopter model parts. Cobb then detailed the ship on paper, from which both a 1/12th scale miniature, and a full-size (front-half only) model were made. The full-size model was built on one of Pinewood Studios largest sound stages, to be used with scenes involving the actors and the M577 Armored Personnel Carrier, and to be concurrent with a miniature set built to act as the Sulaco's hangar bay. Similar looking spacecrafts are seen in Cameron's film The Terminator and its sequel Terminator 2: Judgment Day.

Armament

 * 1 x 25 mm gatling gun with 900 rounds
 * 32 x 150 mm unguided rockets
 * 12 x 70 mm unguided rockets
 * 8 x 120 mm guided rockets
 * 7 x AGM-220 air-to-ground missiles
 * 3 x TSAM threat suppression missiles
 * 3 x AIM-90 short range air-to-air missiles