Historians at Bomber Command Museum in Nanton are thrilled with their latest find.

They now have a very rare H2S Dome for the Lancaster Bomber which fits on the bottom of the fuselage behind the bomb-bay that housed a downward-looking radar transmitter/receiver unit.  

An Edmonton area farmer used it for decades as a mini-greenhouse to give his rhubarb an early start.

Director Dan Fox says it does need a few repairs though.

"The plastic portion of it is all cracked and will have to be replaced," said Fox. "The important thing is the framework underneath, we have that now for a frame and from that we can build a new one."

"They are very rare, you just can't find them anywhere."

The dome covered the H2S, a downward-looking radar transmitter/receiver unit to aid with target finding.

"It was an early form of ground mapping radar that allowed you to fly over land and or water and identify where you were. It was rather crude but it worked really well."

Once it is rebuilt, which will take a while, it will be mounted on the Lancaster Bomber.

"It will make our Lancaster more authentic as a World War Two Bomber," said Fox.

There are a lot of events taking place at Bomber Command Museum in Nanton this weekend so if you wanted to see the dome in person this would be your chance.

Finding planes and parts from farmers used to be easy to do, not so much anymore.

"Most of the World War Two stuff that was on farms has been found and identified."

Fox added they have been lucky over the years with the amount of planes and parts that have been donated to the museum.

"In the 60s and 70s there was a ton of stuff still on farms but gradually as farmers cleaned up their farm yard things were buried and destroyed or they gave it away so there isn't much left."

Which makes this find even more special.