The air frame of the Pelican allows them to carry heavy objects underneath their tail booms. Common carry items include an M12 Warthog, M808 Scorpion tank, troop deployment pods or resupply canisters.
Pelicans receive serial numbers to be identified by during radio transmissions, particularly in combat situations. Each serial number consists of a letter from the Phonetic Alphabet followed by a number. Though a few Pelicans have this number inscribed on their cargo bays, most have no distinguishing mark on their exteriors.
- D75-TC Pelican - A type of Pelican seen in 2526.
- D75/r Pelican - A reconnaissance version of the D75.
- D75/g Pelican - A version of the D75 equipped with a ground support package.[Note 2]
- D77-TC Pelican - The UNSC's standard dropship variant operated during the Insurrection and the Human-Covenant War.
- D77-TAL Pelican - A variant of the Pelican.
- D77C Pelican - Paramilitary variant used by law enforcement in urban areas.
- D77H-TCI Pelican - A better-armed variant of the D77 Pelican, featuring tandem pilot-seating configuration.
- D78-TC Pelican - A less common model used after the Covenant War, with improved avionics and thrusters
- D79-TC Pelican - The UNSC's standard dropship as of 2557, replacing the aging D77 models.
- G79H-TC Pelican - The dedicated gunship variant of the D79 Pelican.
- ONI stealth type - A modification plan used by ONI to retrofit two individual Pelicans (Bogof and Tart-Cart) with numerous upgrades changing their sizes and mission capabilities.
Unidentified Pelican encounters
- Owl - A stealth capable craft, physically resembling a Pelican.
- Condor - Built on the frames of Pelicans though are considerably larger; earning them the nicknames "Fat Pelican" or "SuperPelican".
- In a 2008 interview with Frank O'Connor and Robert McLees, Frank O'Connor and Robert McLees mention that the Pelican as a family of vehicles had been in service for 40-50. It is unknown if this in reference to a specific model and its subtypes or the entire "Pelican" line of ships.
- Chapter 7 of Halo: Oblivion also refers to this type of Pelican as the D75/s. According a tweet by Troy Denning, D75/s was an early name for the vehicle, which was later replaced by D75/g at 343 Industries' recommendation. The use of the term D75/s in chapter 7 was a mistake that slipped through proofreading.