Although considered an official Thunderbird, TBS is not equipped, or often used, for rescue missions like the main five. Instead, TBS is used for bringing criminals who cause disasters to justice (much like Lady Penelope in FAB 1) and for maintaining the security of International Rescue's agents, equipment, and island base. It will often accompany Thunderbird 1 and 2 to the danger zone if the forces of evil are expected to be there waiting for them, or when they simply need an extra pair of wings.
TBS was designed specifically for stealth capabilities, and can fly extremely quietly with incredible agility. Designed and built borrowing designs of combat aircraft, and equipped with vernier nozzles on both the topside and underside of its thrusters, Thunderbird Shadow is the most manoeuvrable and agile of all the Thunderbirds; fully capable of dog fights despite being a rescue vessel. Its ability to seemingly appear and disappear like a shadow has led to the craft being aptly named "Thunderbird Shadow". Its instruments include a light/optic sensor and multi-purpose launchers. The cockpit is actually a motorbike, and can be lowered from the ship belly to be dropped off to the ground in situations where aerial pursuit isn't practical, while remaining in remote control with the main 'body'. True to its name and dedication to stealth, TBS is equipped with two underside claws instead of conventional landing gear, allowing to cling to walls and ceilings, or underneath other aircraft. Thunderbird Shadow also carries built-in cloaking technology, allowing it to become completely invisible both to the naked eye and on radar.
In Power Play, Thunderbird Shadow's engines are upgraded, allowing it to carry one of Thunderbird 2's modules to a danger zone in order to deliver new equipment in the event that the contents of the original module were inadequate for an escalating rescue situation.
- Length: 52 feet
- Height: 6.1 feet
- Wingspan: 26 feet
- Cruising speed: 12,123 mph
- Maximum speed: 14,789 mph
The cockpit of Thunderbird S is a motorbike which can be deployed to the ground from the craft's fuselage when aerial pursuit is not practical, such as when Kayo needs to chase down a target.
Thunderbird Shadow can cling onto walls, ceilings and other surfaces using its grappling claws.
Thunderbird Shadow has electromagnetic cables. When Brains upgraded the engines in Power Play, the craft was able to carry one of Thunderbird 2's modules with them.
Optical Camouflage (Cloaking Mode)
Electronic Control Discs
First seen in SOS Part 2. It is shown that if even one control disc is attached to a vehicle, Thunderbird S can take control of it, so long as they are within effective range.
- Main article: Thunderbird Shadow/Launch Sequence
- Main article: /Missions
- Thunderbird Shadow was designed by Shoji Kawamori, best known for creating the Macross franchise. One notable homage to the Macross series being the fact that TBS has grappling claws instead of conventional landing gear, resembling legs of actual birds, making it strikingly similar to GERWALK mode of the variable fighter crafts from the Macross series when deployed.
- Early sketches of Thunderbird Shadow bear a striking similarity in design to the alternate mode of Cyclonus, an evil Decepticon from the original Transformers series in the 1980's. Incidentally, Kawamori designed many of the original Diaclone toys which would go on to become part of the Transformers line.
- Thunderbird Shadow has its name as Thunderbird S along the front end of its fuselage and on the portside of the cockpit. Confusingly however, its Vivid Imaginations model also has its name on the starboard side of the cockpit, which is never shown in the television series.
- It is technically the counterpart of the Ladybird Jet from the original series, as that plane belonged to Kayo's counterpart Tin-Tin. However, unlike Thunderbird Shadow, the Ladybird Jet was not considered a Thunderbird, or even an International Rescue vehicle.
- Thunderbird Shadow could also be considered the counterpart to Thunderbird 6, as it is the sixth Thunderbird, so to speak. However, Brains was the pilot of Thunderbird 6, although Tin-Tin could fly it, very well in fact.
- Although it was never physically seen it can be assumed that Thunderbird Shadow has some kind of additional seating for passengers as it was mentioned during the season 1 episode Chain of Command, when Brains needed Kayo to give him a ride to a previous accident scene to investigate it for any signs of tampering.