This article is about the diesels. You may be looking for the steam engine, the Story Library book, the cleaner or the porter.

'Arry and Bert (also known as Iron 'Arry and Iron Bert) are twin diesel shunters who work at the smelters and scrapyards of the Sodor Ironworks. They have also been seen frequently working at the Ffarquhar Quarry.


Thomas & Friends

In their first appearance, 'Arry and Bert crept alongside a lonely Stepney, who had been sent to the smelters by mistake. They shunted Stepney into the larger smelting shed underneath a giant grabber and left him there to be scrapped. Thankfully, Stepney was saved by the Fat Controller at the last second.

As well as being villainous, 'Arry and Bert are also known for playing tricks on steam engines such include making them "middle engines". Once, they shunted trucks in front of and behind Percy. This later led him to being pushed onto the coal tipper by mistake. When James took over Percy's duties following the incident, 'Arry and Bert played the same trick on him. Some time later, they gave Fergus - who was tricked into going to the smelters by Diesel - such a fright that he broke the rules and ran away. On another occasion, they bullied Neville by making him think he wasn't close enough to his trucks. This caused him to bump into them and ended up with 'Arry and Bert insulting and laughing at him for his mistake, calling him "clumsy wheels".

On some occasions, 'Arry and Bert's teasing ways backfire; they once played a ghostly prank on Thomas and Emily during Halloween, though they ran away when they thought Emily was a ghost. Another time, 'Arry and Bert teased Percy when he whistled hello. Bert responded by loudly blowing his horn to one-up Percy, rattling him. Percy paid them back by creeping up behind them and blowing his whistle as loudly as possible. Later, they and Diesel began teasing Thomas for being smelly, but later got covered in stinky cheese. By the time they had a washdown, Diesel, 'Arry and Bert were assigned the task of shunting Thomas' delivery of stinky cheese while Thomas got a washdown, much to Thomas' delight.

'Arry and Bert were also part of the group of diesels that took over the Sodor Steamworks. Soon after that, the pair teased Henry because of the coal he had to use by calling him "Mr. Special Steam". They also laughed at Gordon after he ran into Diesel's flatbed and damaged his bufferbeam.

Diesel claimed that his friends, 'Arry and Bert, like him because he is rough and tough, to which they responded in kind as they passed by, despite chasing a butterfly when they said so. Thomas later attempted to blackmail Diesel into being nice with the threat of telling everyone of his secret affection for a group of ducklings. When Diesel broke this promise, Thomas took 'Arry and Bert to the ducklings while Diesel followed behind them. Although Thomas had intended to embarrass Diesel like this, the two found out that 'Arry and Bert also took a liking to the ducklings and are just as big softies as Diesel when it comes to them.

After Diesel had bumped Daisy (which broke her springs), Mavis told 'Arry and Bert that Den and Dart were having trouble fixing Daisy and thought she would be possibly scrapped, horrifying them. They told Diesel, who thought that they were blaming him.


'Arry and Bert are unquestionably devious and scheming. They feel superior to steam engines and working at the scrapyards, they enjoy the chance to break up engines or at least make their lives more difficult. Due to their grim task, they have earned a reputation on Sodor as "The Grim Messengers of Doom". According to their merchandise bios, they wish to scrap Oliver and Stepney who have both escaped the cutter's torch once before. They have also attempted to scrap Fergus.

'Arry and Bert also have a tendency to act scheming, slimy, greasy and oozy, playing tricks and coming up with schemes to make the steam engines' lives miserable and more difficult.

However, despite their prejudices, the diesels have co-operated with steam engines on occasions. The steam engines have also often come to the rescue often when they are in trouble.

They also have a soft spot for ducklings and chase butterflies, and they appear to be more level-headed and have a caring side when it comes to hearing about a fellow diesel potentially having to be scrapped.

Technical Details


'Arry and Bert are based on BR Class 08 diesel-electric shunters. Over seventy members of this class survive today in preservation, while around 100 remain in service on the national rail network. They were in fact the most successful shunting engines in the world, with 996 of them built. Diesel, the Diesel ShunterSplatter, DodgePaxtonSidney, Ulli and the Mainland Diesels are also members of this class.


'Arry and Bert are painted green-grey with yellow hazard stripes on their fronts with yellow cabs. They have "Sodor Ironworks" written on their sides in white.


Thomas & Friends


Music Videos

Learning Segments

Magazine Stories

Audio Files



First used Last used Sound Effect
Calling All Engines! Series 11
'Arry Horn
First used Last used Sound Effect
Series 14 Active
'Arry CGI Horn



First used Last used Sound Effect
Calling All Engines! Series 11
Bert horn
First used Last used Sound Effect
Series 14 Active
Bert CGI Horn


  • The two are not quite identical: Bert has more stubble.
  • Bert is the first character in the franchise to share his name with another character and the second to do so in the television series.
  • 'Arry was the first villain in the series to do an evil laugh.
  • The 1998 Official Website and Question Time with Sir Topham Hatt called 'Arry and Bert "The Yellow Diesels".
  • In merchandising and the official website, the twins are named "Iron 'Arry" and "Iron Bert".
  • 'Arry and Bert were possibly named after the nicknames of two brothers, from the 1970s BBC animated children's show Adventures of Sir Prancelot. These characters full names were Harold and Albert respectively.[3]
  • 'Arry is called "Harry" in the Spanish (from the fourteenth to the sixteenth series), Dutch (in Percy's New Whistle only), German (in Percy's New Whistle and series fourteen and series fifteen), Japanese and Norwegian dubs respectively.
  • 'Arry and Bert's television series models do not have handrails, although some of their merchandise lines do.
  • 'Arry and Bert's fifth series models were repainted and constructed into Splatter and Dodge for Thomas and the Magic Railroad.
  • A model of 'Arry and one of Bert used to be on display in Canada at Nitrogen Studios.
  • 'Arry's name was not revealed until merchandising of him was released.
  • On 'Arry's trading card and Bachmann model, he is depicted with more stubble than Bert, the opposite of how they usually are.
  • There were a few occasions where they went faster than their basis' top speed.
  • 'Arry is the only character whose Mini does not have a classic variant, despite having a DC comics variant. 
  • 'Arry and Bert's liveries might have been inspired by the NS Class 600's livery of black and yellow in some merchandise, even though the NS Class 600 resembles a British Rail Class 11 more than a British Rail Class 08, which is 'Arry and Bert's basis.
  • In Stepney Gets Lost, their engine sounds are shared with Rusty and Derek from the fourth and fifth series.
  • The twins are accompanied by a triplet in the 2006 video game, Right on Time.


Stepney was all alone, but not for long. Two diesels approached.
"Got ya this time, Stepney. You'll make very fine scrap indeed. Buffer 'im, Bert!"
The diesels took him to the large smelting shed
"Bye-bye, Stepney!"
said the diesel.
―'Arry and Bert's introduction, "Stepney Gets Lost", fifth series
The next day, James arrived at the smelters. He was determined not to be tricked by 'Arry and Bert.
"'allo, James!"
oozed 'Arry. "Come to learn a thing or two from those who know?"
"Just get my trucks ready and stay out of my way!"
huffed James importantly.
"Yes, sir".
Bert chimed greasily.
―James meets 'Arry and Bert, "Middle Engine", sixth series
Fergus and his driver arrived at the smelters.
"I want to go back to the Cement Works! None of the other engines like coming here, its so scary!"
"You're right!"
said his driver.
Just then, the scrap diesels emerged.
"'Ello! Are you happy to be here?"
cried Fergus.
―Fergus meets 'Arry and Bert, "Fergus Breaks the Rules", seventh series


  • ERTL (discontinued)
  • Wooden Railway (normal, oil-covered; discontinued; cheese-covered Bert; discontinued)
  • Take Along (normal and metallic; discontinued)
  • Take-n-Play (discontinued)
  • TrackMaster (discontinued)
  • Bachmann (discontinued)
  • Hornby (discontinued)
  • Lionel (discontinued, later reintroduced with LionChief remote)
  • My First Thomas ('Arry only with Bert's face discontinued)
  • My Thomas Story Library (discontinued)
  • Trading Cards (discontinued)
  • De Agostini (discontinued)
  • Minis
    • Classic Minis (Bert only)
    • Neon Minis (Bert only)
    • DC Super Friends Minis ('Arry as Shazam (2015 & 2016) and Bert as Shazam (2017))
    • Electrified Minis (Bert only)
    • Space Minis (Bert only)
    • Aquatic Minis (Bert as a jellyfish; with 'Arry's face mask)
  • Adventures (Bert only; discontinued)


* RWS only | ** T&F only | --- Dropped

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