Examples from the Web for undercarriage
The wheels of the undercarriage have a way of throwing up mud on to the lower surface.The Aeroplane Speaks|H. Barber
So close was the other upon him that he imagined he could feel the wheels of the undercarriage on his own wings.Aces Up|Covington Clarke
I busted a wing and wiped the undercarriage right off, and didn't get a scratch.Dave Dawson at Dunkirk|Robert Sydney Bowen
Then he touched a button and the pontoons were drawn up into the undercarriage of the craft.
The propeller is gone, and maybe the undercarriage is damaged some.The Flying Reporter|Lewis E. (Lewis Edwin) Theiss