Arrived after a 5 hour sector to find ice on the upper wing surfaces. The ice extended from approx 2 ft inboard of the engine pylon to about 6 ft outboard. A very small amount was evident at the wing tip also.
We refuelled uplifting 1800 Kg's to each wing tank. The ice remained even after refuelling. OAT was 24 C. with fuel tank temp 16 C after refuelling. Cruise TAT for the flight was @-35 C. Virtually no visible moisture for the entire flight.
We attempted to 'wash off' the ice with water from the 'potable water' bowser. (De-icing not available) This made matters worse with some of the water freezing again. Eventually we managed to get hold of an airport fire truck and applied large amounts of warmish water which did the trick.
I have to confess to being very surprised that refuelling did not clear the original ice.
Regards
Exeng