"They're crazy! It's probably a million to one chance we'd get hit."
— Jim

"Edge Of Impact" is the fifth episode of Thunderbirds season 1, originally broadcast on 28th October 1965.


Two men, in their control room atop the British Telecom Tower, are imperiled when an aircraft sabotaged by The Hood crashes into the tower, leaving it in danger of collapse. They can't be rescued directly, however: the tower's swaying precariously in the windy conditions of a full-on gale. Their only hope is International Rescue - but the Thunderbirds' mission to save them has been complicated, by the presence of an unexpected guest on Tracy Island...


Main article: Edge Of Impact/Storyline


Main article: Edge Of Impact/Transcript


Regular CharactersEdit

Guest CharactersEdit

Cameo RolesEdit

International Rescue Equipment UsedEdit

Non-International Rescue Equipment UsedEdit



  • John "appears" in this episode only via the flashing ocular lights in his Operation Cover-up portrait (see Transcript).
  • The TX-204 aircraft originally seen in Trapped in the Sky appears briefly in an establishing shot of the airfield. A WASP Spearhead bomber from Stingray is also visible in the background.
  • This episode takes a notable departure from the usual pre-launch scenarios of Thunderbirds 1 and 2 - both take place in complete silence. No musical underscore (or radio contact) is heard - only the odd sounds and echoes of the hangars' massive machinery, are heard - not until Scott and Virgil finally get the word from their father that the coast is clear for them to take off!
  • Tim Casey also appears as a bank executive in the opening shots of Vault Of Death.

The Hood's Laundry Truck

  • The Hood's North Pole Laundry Truck is revamped from Ned Cook's broadcasting truck seen in Terror in New York City.
  • ​Braman, Brains' robot from Sun Probe, can be seen in Brains' laboratory.
  • This is one of the few episodes in Australia where a subtitle is added; 'Part 1' is shown under the title in the Australian 30 minutes cliffhanger version.
  • The Hood gives his codename as '671' when he contacts General Bron.
  • Jeff's comments about their unexpected visitors being "more of Tin-Tin's admirers..." refers to the events of End Of The Road, which confused many people as this episode was broadcast after Edge Of Impact.
  • In a startling prediction of the future, the relay tower is shown to be owned by British Telecommunications Ltd; the real life British Telecommunications didn't come into existence until 1980, 16 years after this episode was produced.
  • The shot of the Target Ship exploding is stock footage lifted from the start of the Stingray episode Star of the East.


  • Tim Casey is a colonel, but Scott refers to him as a "General" in one scene. ("I guess I just thought that with you and the 'General' being buddies in the early days...")
  • In the close-up puppet shots of Virgil at the danger zone, he is wearing a white coat, but in the model long-shots, he isn't wearing it.

Alternate VersionsEdit

Thunderbirds (FOX Kids Series)Edit

For a contemporary (or at least in the 1990's) audience, Thunderbirds underwent a repackage, redub, and rebroadcast as part of FOX Kids' Saturday morning line-up. The sixth story to be produced in this fashion was Edge Of Impact, first (and last) aired on August 6th 1994 at 8:30am.

Foreign TitlesEdit

  • French: Essais en vol
  • German: Red Arrow ausser Kontrolle
  • Italian: Impatto imminente
  • Spanish: Impacto Inminente; Al borde del impacto (DVD)
  • Dutch: Sabotage (TV 1967); Op het randje na dood (TV 1991); Een vlijmscherpe inslag (DVD)
  • Japanese: 超音ジェット機レッドアロー


Main article: Edge Of Impact/Gallery