Departed Grand Forks AFB, headed south then west. The low level entry point was in western South Dakota and there was a front between where we were to where we needed to be. Cruised south along the front at about FL240 looking with radar for a hole between thunderstorm cells big enough to slip through. Found on and called for the turn. We went from warm and sunny to wet to a Popsicle in short order. It was cold across the front and we iced up fast. All the engine over temp and fire lights came on. Indicative of inlet icing. The pilot called for an emergency decent with center and asked me where cloud base was. 10,000 MSL was the briefing. We burst out into sunshine at 12K MSL and all the lights went out.

Everything was in order, all the gauges checked and we head for the low level route (IR472). We fly the training mission and return to base. Reporting the icing encounter at maintenance debrief and word comes back from the flight line, 3 of the 4 engines have bent fan blades and vanes in the first to stages. But the engines never complained, no vibrations recorded. They are heavily instrumented and our on board systems report and record everything real time. Just could no kill those GE jets. B-1B aircraft.

BillT