Schmleff
Well-Known Member
*THIS LIST COULD SAVE YOUR LIFE*
In light of the recent Sonerai crash I am starting this thread to help people that are new to VW engines and props determine what may be considered "normal" power output. It is impossible to truly determine power output by static rpm's, but if the prop size and manufacture are listed with the rpm, we can at least establish some sort of a baseline.
Be careful to read this with caution. What may fly a Sonerai I may not fly a Sonerai II with a passenger. No two aircraft are alike. Even different Sonerai II's may have dramatically different drag characteristics. By no means is it intended to be a "fly" or "no fly" list. It is offered to throw up a red flag for someone that sees numbers lower than listed. It is offered as a safety precaution only.
If John had had such a list available to him, he may have seen that 3000rpms static on a Sterba 54x44 with a 2200cc engine was abnormally low. When I had spoken to him by phone during the preceding week, I asked what his static rpm was. He had not been able to do a full power static run up at that point. I do not fault him or not knowing this information as there was no way for him to know what "normal" should have been.
Please list only documented numbers. Please list them in this format:
Aircraft: Which Sonerai
Fly with passengers: Yes or No
Gross Weight: 0000
Engine: VW 0000cc's, bore x stroke
Carb: Whatever carb used including throat size
Prop Manufacutre: Whatever
Prop dimensions: diameter x pitch
Prop alterations from stock: did you cut the tips? How much
Static RPM: 0000
Please be as accurate as possible. I will edit your entry for clarity if I see the need.
In light of the recent Sonerai crash I am starting this thread to help people that are new to VW engines and props determine what may be considered "normal" power output. It is impossible to truly determine power output by static rpm's, but if the prop size and manufacture are listed with the rpm, we can at least establish some sort of a baseline.
Be careful to read this with caution. What may fly a Sonerai I may not fly a Sonerai II with a passenger. No two aircraft are alike. Even different Sonerai II's may have dramatically different drag characteristics. By no means is it intended to be a "fly" or "no fly" list. It is offered to throw up a red flag for someone that sees numbers lower than listed. It is offered as a safety precaution only.
If John had had such a list available to him, he may have seen that 3000rpms static on a Sterba 54x44 with a 2200cc engine was abnormally low. When I had spoken to him by phone during the preceding week, I asked what his static rpm was. He had not been able to do a full power static run up at that point. I do not fault him or not knowing this information as there was no way for him to know what "normal" should have been.
Please list only documented numbers. Please list them in this format:
Aircraft: Which Sonerai
Fly with passengers: Yes or No
Gross Weight: 0000
Engine: VW 0000cc's, bore x stroke
Carb: Whatever carb used including throat size
Prop Manufacutre: Whatever
Prop dimensions: diameter x pitch
Prop alterations from stock: did you cut the tips? How much
Static RPM: 0000
Please be as accurate as possible. I will edit your entry for clarity if I see the need.