The floating crane was a type of crane seen in Day Of Disaster.
Three floating cranes were hired by the bridge controller to clear the wreckage surrounding the Martian Space Probe, so the two US technicians inside could be rescued. Unfortunately, when the wreckage turns out to be beyond the cranes' lifting limits, one of the cranes loses its balance, capsizes, and falls into the water.
Behind the ScenesEdit
It is obvious that these models were made from Airfix kit parts. Kits probably used (among others) were the Airfix Girder Bridge and the Travelling Crane.