While developing the Halo games, Bungie, 343 Industries and Ensemble Studios have had to cut some content, such as vehicles, gameplay, and story elements, from the final products. Much of this content has been confirmed by videos and commentary in special edition DVDs, interviews with developers, and released concept art.
- The Kestrel may have been an early version of the Hornet or Hawk, as both are quite similar looking.
- Since the Kestrel is an aircraft, it may have had weapons similar to the Hornet's, such as the machine gun and missiles. It may also have been used to transport troops quickly if it were to have a troop bay, much like modern helicopters.
- The name Kestrel was also that of a cargo ship in Halo: The Cole Protocol.
- It was placed by modders into custom maps available only to Halo Custom Edition.
- The name Kestrel was found in the Halo Combat Evolved game code.
- The aircraft could possibly be named for the Hawker-Siddeley Kestrel FGA.1, the direct forerunner and prototype of the Hawker-Siddeley Harrier jump-jet, One of the 3 VTOL aircraft currently in active service.
- The concept art for the Kestrel resembles the Gunship from the Half-Life series.
- A common Kestrel model in Halo: Custom Edition closely resembles the UH-144 Falcon from Halo: Reach, these models are often armed with a four-barreled version of the M41 LAAG and a four-shot rocket pod mounted below the craft's tail section.