Pipistrel Cowl flap review

Pipistrel has a new cowl flap for it’s Virus SW aircraft. It’s main purpose is to increase engine temperatures for us who live in colder climates. It also has the potential to increase engine cooling by creating lower pressure inside the engine cowl and sucking the air through quicker, but I won’t be able to test this until some hot air comes to Canada.

I have just 10 hours on the airplane, but have begun testing the cowl flap’s impact on engine heating performace. During the last flight the outside air temperature while in flight was -3ºc (26.6ºf). Not overly cold but cold enough to test the flap. With the flap fully open for 10 minutes in cruise oil temp was 87ºc and coolant was 55ºc, now after closing the cowl flap and waiting 10 minutes the oil temp rose to 98ºc and coolant 79º. I could also notice a significant improvemnent in cabin heat. I would recommend this new modification to anyone flying in cold weather climates. Most of you will be interested if it will help to cool the 912 iS engine on hot days so stay tuned for those results.