Screen Demisting

[Skycop]

Anyone have any experience of keeping plastic screens mist-free? (We have a problem these cold nights due to immediate readiness requirement of job).

[Bladestrike]

With Jetrangers working in the artic, we used to put car warmers (those little fan powered plug-in heaters) on the floor in the cockpit, that worked well. Although not enviromentally friendly, try carrying a jug or two of car-windshield washer fluid, the winter stuff thats good to minus 40, and pour that over frosted or lightly iced plexiglass windows, works better if its warm. Check with your engineer first though. Also, we always killed the a/c heaters before final so the windows had a chance to cool before landing, otherwise blowing snow would melt on them if they were too warm then freeze and make a hell of a mess. Good luck!

[Skycop]

Thanks Bladestrike, we are on the same wavelength. I have been trying to source a suitable electric heater for inside the cockpit but even manufacturers can't tell me if their heaters are suitable for use inside a heli. Any pointers? Unfortunately manufacturer specifically does not recommend use of any de-icing fliud on the glazing!! This is echoed very strongly by our chief engineer. Tonight we again had to push the A/c back inside the hangar to demist the screens - not very satisfactory even though it's a mere 2 tonnes between 3 of us!

[Bladestrike]

Yea, I wasn't too sure if the windshield-washer fluid was cool, back in the old days in the bush, we just used whatever worked, and it worked well, and was a hell of alot cheaper than fluids designed for aircraft. As far as heaters, depending on where you are, in Canada we have a Canadian Tire store in every community, and car heaters are readily available, in every shape and size. If we didn't have a hangar, (often) we had insulated covers for the bird and had heaters in the cockpit, one in the transmission bay, and one in the engine bay, and I don't think they use them anymore, but battery heating blankets for our batteries too. Lots of juice required! Our baggage compartments were always full in the winter!
They started nice and were pretty warm when required if you were quick getting started after pulling off the covers, and if electricity wasn't available, we'd start her up every hour for ten minutes, but I'm rambling now. Try any auto-parts store, they should be able to get you something, and while they shouldn't be too close to the plexiglass, there generally not strong enough to do any damage. Once again, good luck.

[neverinbalance]

Only way I have found is to keep it in the hangar. You will have to convince the old bill to buy a trolley or spotter so you don't waste time and energy pushing the thing!

[Skycop]

Thought so, working on "spotter" already but dosh is short due to near end of FY! We've got a trolley but it's u/s long term..p.s. you at PAS or other?

[This message has been edited by Skycop (edited 30 January 1999).]