Originally Posted by
Mad (Flt) Scientist
A Q400 is 108ft long and just under 9ft wide. For a simplified (rectangular) fuselage plan area of just under 1000 sq.ft. Call it 100m^2. If you had an inch of solid ice over the whole fuselage, you'd have 2.5m^3 of ice. Ice has a density of just under 1tonne/m^3. So that truly ridiculous amount of ice would weight 2.5 tonnes.If you took a more reasonable thickness of ice, a more reasonable assumption of where it would adhere and of the real fuselage area, you'd be down in the hundreds of kg.
More importantly, managing to accumulate such a ridiculous amount of ice and not have the wings contaminated is practically impossible - you'd have to sit in freezing rain for hours, and no anti-icing fluid can protect the wings for that long in similar conditions. if you look at some typical HOT values and some assumed precip rates, you'll find 1/4" or less of ice is more what you might see.
To Add
The basis of the icing regulations assumes continuous icing within appendix "C"
Thus no limitation on time, But you would be extremely unlikely to find ridiculous icing conditions (outside appendic "C") in continuous flight
Even without anti-ice fluid, de-ice devices etc. The insulation effects of the ice on the aircraft surfaces (adherence) coupled with in-flight windage would produce self shedding before dead weight became a problem (unlike naval vessels
