Was wondering what kind of flight times I can expect with an OS 91 fx in my Sig 4 star 60 ARF. I'm using the stock tank which is 380 cc (12.8 oz). The OS manual recommends a 450 cc tank which would allow approx. 12 - 13 minute flights. Since the Sig tank is slightly smaller I'd like to hear from anybody using this combination, how you like it, flight times, and anything else you'd like to share. Thanks for any input.

Joe

7-8 minutes with some reserve, if you fly 3/4 throttle........

thanks JB.

Hmmm.. may need a bigger tank. Darn.

With that size engine, you will not be flying at more than 1/2 throttle for most of the time. 10 minutes max I would expect. Build it strong so you will not rip the wings off.

The 91 will get almost the same flight time and fuel economy as the 61 if you fly at the same speed, the 91 at 3/4 throttle will use almost the same amount as the 61 at full throttle. Throttle control is the key to fuel economy but when you have a 91 at your finger tips you will begin to PLAY, and ALL OUT FUN comes at a price, (shorter flight times) but 7 to 8 min of action packed craziness is all my nerves can stand anyway.