He worked on the show from 1984-2003.
Mitton wrote six episodes of "TUGS" and directed nine of them. When Clearwater Features closed down, he joined the Britt Allcroft Company.
Although some episodes were based on Railway Series books, some of the script was written by him and Britt Allcroft. After the death of the Reverend W. Awdry in 1997, Mitton and Allcroft decided to create stories of their own. He provided stories for episodes of the sixth and seventh seasons. His last episode as writer was Edward the Very Useful Engine, but he continued as director until Three Cheers for Thomas before retiring. Steve Asquith replaced him as director from then on. David was also a model unit creative consultant for Thomas and the Magic Railroad.
He was working with Gerry Anderson producer David Lane with their own company "Pineapple Squared Entertainment", which was due to launch a new CGI Animation series "Adventures On Orsum Island". Only a few episodes of "Orsum" were semi-completed before his death.
Sadly, David Mitton suffered a heart attack and died on May the 16th, 2008, at the age of 69. His death was not announced until May the 28th, 2008. Many "Thomas the Tank Engine" and "TUGS" fans were greatly saddened by this news.
All episodes are co-written with Britt Alcroft and nine episodes were co-written with Alcroft and David Maidment.
- Cranky Bugs
- Horrid Lorry
- A Better View for Gordon (with Alcroft and Maidment)
- Lady Hatt's Birthday Party (with Alcroft and Maidment)
- James and the Trouble with Trees (with Alcroft and Maidment)
- Gordon and the Gremlin (with Alcroft and Maidment)
- Bye George!
- Baa! (Alcroft and Maidment)
- Put Upon Percy
- Toby and the Flood
- Haunted Henry (with Alcroft and Maidment)
- Double Teething Troubles (with Alcroft and Maidment)
- Stepney Gets Lost
- Toby's Discovery
- Something in the Air
- Thomas, Percy and Old Slowcoach
- Thomas and the Rumours
- Oliver's Find
- Happy Ever After
- Sir Topham Hatt's Holiday
- A Surprise for Percy
- Make Someone Happy
- Busy Going Backwards (with Alcroft and Maidment)
- Duncan Gets Spooked (with Alcroft and Maidmnet)
- Rusty and the Boulder
Awards and nominations
- Nominated - British Academy of Film and Television Arts - Best Animated Film for "Thomas The Tank Engine & Friends", 1985, shared with Britt Allcroft and Robert D. Cardona; 1987 shared with Robert D. Cardona.
- Teresa Gallagher and David Menkin would soon become voice actors on the fiftieth anniversary reboot of the original Thunderbirds series, the latter which David Mitton worked on.