Winter Ops at Ladd Field. This unidentified F-13 is being heated by a period "space-heater" or "Herman-Nelson" with multiple hoses. The custom engine cowling covers will keep the engines and oil tanks warm long enough for all of the engines to easily start. The ground-crew wear the latest Alaska-Arctic fashion clothing, heavy military parkas. (Photo from Col. B.C. Barris, AWRA)