Duncan and the Hot Air Balloon
S12:E11
2008
IMDb
It's the Percival twin's birthday, and Duncan is to give them a special birthday ride, just as he always does. Duncan is getting his special birthday flag fitted, just as the Thin Controller, Mr. Percival, arrives with news. He asks Duncan to collect a hot air balloon from the Transfer Yards. The twins will be getting a ride in a hot air balloon for their birthday.