... wonder if they really burnt one of the Widgeons! I've seen the film and it doesn't look like a model that they break. Could have been a prop I suppose..
I reckon it was a surplus/damaged fuselage. It looks too good to be a mock-up to me - even on some modern 'big budget' numbers the mock-ups can be pretty dire. The Huey in 'Sahara' that gets shot down for example, to name just one.