Mighty Mac is a double-ended Fairlie duplex locomotive. 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.
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), 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 is 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're lined with red.
- Taketoshi Kawano (Japan)
- Unlike most double fairlies, Mighty Mac has a whistle at both ends of their model.
- Mighty is the only engine to have what appears to be hair.
- In Season 11, their whistles were changed to Harvey's at a high pitch.