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Mighty and Mac are a double-ended Fairlie duplex locomotive, and conjoined twins. Mighty is the "older" of the two and is distinguished by a small flick of hair. Mac is the "younger" half and is distinguished by his youthful features, round nose and freckled cheeks.

Despite the opposing personalities of the two ends, they are technically one engine.


Thomas & Friends

Prior to their adoption into the Skarloey Railway family, Mighty Mac had only worked in the shunting yards. Their lack of knowledge beyond their boundaries created much conflict between the two halves (for example, which end is in charge of doing what) when they pulled their first train, which placed themselves and their passengers in great danger whilst running an important errand. But, with advice from Thomas in mind, they were able to complete their task and realise the value of working as one.


Mighty Mac are two engines in one. He is Mighty on one end and Mac on the other-- making him one of the most unusual engines working on the Skarloey Railway. When they work together, Mighty Mac is the strongest engine on the Railway. But when they do not, Mighty and Mac pull each other backwards and forwards, only to end up right where they began.

Technical Details


Mighty Mac is based on Merddin Emrys, a Double Fairlie locomotive of the Ffestiniog Railway with added buffer beams. Livingston Thompson from the same railway appeared in the 1979 Annual and is preserved at the National Railway Museum. Three more of these are currently in service on the Ffestiniog - and another is under construction at Boston Lodge.

Mighty Mac has been modified in order to work on the Skarloey Railway. Whereas their original basis was built to 1 ft 11 1⁄2 gauge, Mighty Mac was built to 2ft 3in gauge and they have been given buffers and screwlink couplings in order to work with the other engines.


Mighty and Mac are painted royal blue with yellow and red lining. On Mighty's side, his cab windows and tank caps are lined with yellow, while on Mac's side, they are lined with red.


Audio Files



When you play Mighty's original whistle sound from the ninth series, it is higher-pitched and it plays Bert/Rebecca's whistle sound.

First used Last used Sound Effect
Series 9 Series 9

In Series 10 and the twelfth series episode Mountain Marvel, he and Mac had Sir Handel's whistle.

First used Last used Sound Effect
Series 10 Mountain Marvel
First used Last used Sound Effect
Series 11 Read and Play!



First used Last used Sound Effect
Series 9 Series 9
First used Last used Sound Effect
Series 11 Read and Play!


  • Mighty is the only engine to have hair (excluding facial hair).
  • Mighty Mac has used five (their Series 9, Sir Handel's and their Series 11 whistles) whistle sounds in the television series. Also, they have a whistle at both ends of their model unlike most Double Fairlies.
  • Mighty's original whistle sound from the ninth series only was reused for Bert and Rebecca, but at a higher pitch.
  • Mac's original whistle sound from the ninth series only was reused for Rex.
  • Out of all the characters introduced in the ninth and tenth series, Mighty Mac is the only one to not be mentioned in the song, "There's Always Something New".
  • In the German dub since the tenth series, Mighty Mac has been called Big Mac, which is also the name of a TUGS character.
    • In the ninth series, they were called Mac Nic. 
  • Mighty's hair changed position on his face masks, depending on what emotion he was expressing.
  • Mighty Mac is the first narrow gauge character not to have a small-scale O gauge model.
  • Mighty Mac's television series model is currently on display at Drayton Manor Theme Park and are wearing their happy face masks.
  • Mighty's whistle sound from Series 11 to Series 12 is reused from Gertrude in the British preschool series Peppa Pig.
  • Mighty Mac's eleventh series whistle sounds are Harvey's current whistle sound from the twelfth series onwards, but at some steps higher-pitched, before Harvey's current whistle sound was first heard and used.
  • Mark Moraghan gave Mighty Mac a cockney accent in the mobile game app Read and Play!.


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