The title of this article is conjectural. Although this article is based on
information, the actual name of this subject is pure conjecture.
6'7" ft. (Average)
Flame Drones were variants of Drones that only appeared six weeks after Emergence Day. Flame Drones carried fuel tanks on their backs attached to a Scorcher Flamethrower, similar to that of Flame Grenadiers and Flame Boomers.
Flame Drones were encountered inside the
Museum of Military Glory attacking Kilo Squad as the Gears tried to defend the Nassar Embry armor display. They were later encountered again breeching the Courthouse and attacking the  Onyx Guards inside.
While they did carry a
Scorcher Flamethrower and back-mounted fuel tanks similar to the Flame Grenadier and the Flame Boomer, they did not wear the same helmet as them. Instead, they wore standard Drone helmet variations. They also had less health then a Flame Grenadier, having the same health as a regular Drone.
The Flame Grenadier depicted with a Drone's body character model in the cutscene.
In the deleted scene Gears of War 2 Road to Ruin, there is an error shown when you distract two Drones and a Flame Grenadier with a concrete block. During the cutscene that plays, the Flame Grenadier is depicted having the character body model of a Drone. 
Hollow and Enemy Creatures
( Berserker Matriarch) · ( Boomer Butcher, Flame Boomer, Grinder, Mauler, Mauler Elite, Savage Boomer, Tremor) · ( Drone Beast Rider, Bolter, Cleaver Theron, Cyclops, Disciple, Flame Drone, Flame Grenadier, Grappler, Grenadier, Grenadier Elite, Gunner, Hunter, Hunter Elite, Miner, Palace Guard, Rager, Savage Drone, Savage Grenadier, Savage Grenadier Elite, Savage Hunter, Savage Marauder, Savage Theron, Sniper, Spotter, Theron Elite, Theron Guard, Theron Sentinel) · ( Kantus Armored Kantus, Savage Kantus, Zealot) ·
Bloodmount · Brumak · ( Corpser Shibboleth) · Digger · Gas Barge · Heart Leech · Kraken · Kryll · Leviathan · Mangler · ( Nemacyst Ink Grenade) · Nemacyte · ( Reaver Assault Barque, Hydra) · Riftworm · Rockworm · Seeder · Serapede · Siegebeast · ( Tempest Shrieker) · Ticker · Torture Barge · Wretch
Former · Lambent Berserker · Lambent Brumak · Lambent Bull · Lambent Dog · ( Lambent Drone Lambent Drudge) · Lambent Gunker · Lambent Leviathan · Lambent Polyp · Lambent Stalk · Lambent Wretch
Canker · Carrier · ( DeeBees Bastion, Reject, Stump) · ( Drone Elite Drone, Grenadier, Elite Grenadier, Hunter, Elite Hunter, Imago, Sniper, Elite Sniper) · ( Flock Leech) · Hive Beast · ( Juvie Screamer, Popper) · Kraken · Locust Drone · Matriarch · Pouncer · ( Scion Armored Scion, Heavy Scion, Scion Elite, Warden) · Sire · Snatcher · Swarmak
DR-1 · ( Shepherd Deadeye) · ( Tracker Shock Tracker) · ( Watcher Guardian, Sentinel)