Thunderhawk
The standard air support and transportation vehicle for the Space Marines. Comes in two variants, the Thunderhawk Gunship and the Thunderhawk Transport. The gunship variant can hold thirty Space Marines inside (or fifteen Terminators, three Dreadnoughts, or some combination thereof), and sports the massive Thunderhawk Cannon (or a Turbo-Laser) on its back. The transport variant has two clamps on the recessed underside, for carrying either two Rhinos or one Land Raider underneath it. Both variants have missile/bomb pylons and multiple remotely-operated twin-linked heavy bolter turrets on the wings and hull.
The Thunderhawk replaces the Stormbird transporter, which is larger, more heavily armed and capable of carrying more cargo than a Thunderhawk Gunship and Transporter combined, up to 50 Space Marines. As the demand for dropships increased during the Great Crusade, the Thunderhawk was created as an easy-to-produce alternative for the Unification War era Stormbirds, though considered inferior in quality. After the Horus Heresy, it was decided that putting one twentieth of a Space Marine Chapter in a single vessel was a bad idea, so the Stormbird was mothballed after the Codex Astartes reform.
The Thunderhawk started out life in Epic as essentially a flying Rhino (in other words, they were METAL BOXES); it had a stumpy battle cannon and wings three scale feet thick. This persisted through a number of horrendous-looking scratchbuilds before eventually someone at Games Workshop had the bright idea of producing a limited-edition £400 Thunderhawk in lead for 40K, with a much longer hull, proper, manly wings, and loads of weapons. These were given away as the non-useless prize for winning Golden Demon along with the usual Slayer Sword a couple of times, until GW saw there was a Market and Forge World took up the slack. Forge World still sells Thunderhawk models, both in Transport and Gunship varieties, with several options for molded livery and (for the Transporter) vehicles to be carried.
New Model
In April 2017, Forgeworld released the new resin Thunderhawk model that replaced the old iconic flying brick. The new model is actually god damned aerodynamic for once and actually looks like it could actually fly rather than the usual Space Marine modus operandi of strapping wings on a cargo container and duct-taping some rocket engines to the whole mess. The new Thunderhawk model boasts a slimmer and sleeker fuselage, a smaller and less pronounced Thunderhawk Cannon, and a less conspicuous cockpit than the previous model, as well as having larger wings to make them a little more proportional to the newly elongated body. Unfortunately the new model removed the horizontal stabilizer from the tail plane, resulting in much despair. It is also a little smaller than its predecessor, with a less conspicuous profile.
The new model is also pretty customizable. The smaller wings can still be glued at your preferred angle, (LOCK X-FOILS IN ATTACK POSITION!) and the heavy bolter turrets on the wings and nose are both capable of rotating (rotatable?). The side doors of the troop bay can also be swapped out for any of the Forgeworld sculpted vehicle doors as they are the same size as the ones on the standard metal box.
So far reviews from high rollers who can actually afford the typically high forge world price have been largely positive.
Ætos Dios
Also known as the Aetos Dios because people can't type Æ. The Ætos Dios is a modified Thunderhawk exclusive to the Imperial Fists Primarch, Rogal Dorn. This flying rape-engine was first conceived after following several failed attempts on Rogal Dorn's life following the outbreak of the Horus Heresy. Magos Telluria constructed for Dorn a unique, heavily-customized personal Thunderhawk gunship to both convey him in battle and to shield him as he conducted missions in the defense of Terra.
It is quite befitting that Rogal would have his own personal jet plane fit for a Primarch to oppose Perturabo's personal rolling bunker.
The Ætos Dios differs from the bog-standard Thunderhawk, by being equipped with a Turbo-Laser instead of the Thunderhawk Cannon and a single Titan Void Shield. Making it a flying Titan.
In terms of tabletop the Ætos Dios is usable in games of 3000+ points as a dedicated transport. It has the IWND special rule and a 4+ invulnerable save against all missile attacks.
Plastic Thunderhawk
Of all the rumours that saturate 40k, the myth of a Plastic Thunderhawk is the Unicorn, one that people forever seek and yet will never find. Ever since GW began to make Plastic Superheavies starting with the Baneblade, rumours, hints and wishes for a Plastic Thunderhawk have flitted across the internet. When in 2017 the old Resin Thunderhawk was retired, those dreams once again reared their heads and fueled by rumourmongers hype for a Plastic Thunderhawk spread across the usual sites like Bell of Lost Souls and Bolter and Chainsword. Then it was revealed that it would be yet another Resin Thunderhawk, and once more the dream died. To this day though people still cling to the hope that one day the Thunderhawk will be made in plastic and thus affordable without selling half your internal organs.