Viscount 700 De-icing criteria...

[Macs]

Hi,
One more for the Viscount 700 or any plane with Darts for that matter. Having had a few engine failures, which I attribute to de-icing mismanagement, I was curious what the criteria was for engine failure due to icing and the usage of the PUD's as the manual says:

-"The PUDs should be selected to low when the outside air temperature falls below +10’C and to high in temperatures below -6’C.
Note that the system has been arranged such that engine flame out may occur if the deicing equipment is not used correctly in icing conditions"

I do operate them, but not sure how frequent. I also keep check on TGT's, fuel filter de-icing and air-frame de-cing (which I am curious how to operate correctly too). Thanks in advance for your help, and sorry to bother you all so much
regards,
Macs

[Viscount Cornbank]

Hi Macs,

If the PUD switches, (big wooden pull/push type) are on and the cyclic timer set correctly, the green integral lamps cycling, then an engine cannot flame out due to icing. The fuel heaters should be on in OATs below about -19 and the filters will be safe from blockage. Airframe anti ice should be operated as with the PUDS, although it may be necessary to turn it off on one side to prevent overheating in higher temps.

cheers

Fraser

[Macs]

Many thanks again Fraser, I actually managed to do a pretty decent flight today, following your recommendations/explanations. Thanks,
regards,
Macs