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Not totally following I am hovering really around 5175 - 5210 wot climb out. Cruise at 5500 level staying In the LSA 120 kts range, but can push it put to 5700 for 5 min which I don’t do. I think if I flatten the prob I will get more rpm on climb but less speed on top end. I’m happy with the climb I have it is outstanding.ShawnM wrote:I'd still correct the pitch issue you have as you can damage the engine if you are not careful.
If you don't use the 5,700 setting then maybe your too flat? If you set for the highest number you use you would pick up a little power in the range that you do use.David wrote:Not totally following I am hovering really around 5175 - 5210 wot climb out. Cruise at 5500 level staying In the LSA 120 kts range, but can push it put to 5700 for 5 min which I don’t do. I think if I flatten the prob I will get more rpm on climb but less speed on top end. I’m happy with the climb I have it is outstanding.ShawnM wrote:I'd still correct the pitch issue you have as you can damage the engine if you are not careful.
Open for suggestions
Being under pitched is not an issue for the engine unless you are going past redline. Being over pitched is bad in almost every regard. It sounds like he is just slightly under pitched.ShawnM wrote:
I understand that YOU are happy with the climb that you have but IS YOUR ENGINE?
This is why Roger suggests you go WOT for 1 minute at your average cruise altitude, so you can see where the RPM settles in at. David stated he can push it to 5700 rpm, will it go higher? We dont know until you go WOT and find out. It may go to 5800 during that minute. Again, this is why we do the test. I'm just offering up the same info Roger has posted more times than I can count in all the various forums.3Dreaming wrote:Depending on the airframe 5700 over 5650 is not enough to worry about an adjustment, unless you are trying to get the best all around performance. Prop pitch is kind of like deciding which airplane is the best choice. You have to define your objective on what performance you want.
When he says he can push it to 5700 for 5 minutes I take that to mean 5700 is as fast as it will turn full throttle level flight.ShawnM wrote:This is why Roger suggests you go WOT for 1 minute at your average cruise altitude, so you can see where the RPM settles in at. David stated he can push it to 5700 rpm, will it go higher? We dont know until you go WOT and find out. It may go to 5800 during that minute. Again, this is why we do the test. I'm just offering up the same info Roger has posted more times than I can count in all the various forums.3Dreaming wrote:Depending on the airframe 5700 over 5650 is not enough to worry about an adjustment, unless you are trying to get the best all around performance. Prop pitch is kind of like deciding which airplane is the best choice. You have to define your objective on what performance you want.
If I were to bolt on this expensive upgrade I'd want "the best all around performance" I could get for my money, wouldn't you? My point is he may be leaving some performance or fuel savings on the table without knowing it. That's all.
Correct i can push it up to 5700 ish at level flight for 5 min, but cruise at 5500 - i think it is dialed in, but i could bore wrong.3Dreaming wrote:
When he says he can push it to 5700 for 5 minutes I take that to mean 5700 is as fast as it will turn full throttle level flight.
There is no requirement for the pilot to maintain 120kt or less. That is a requirement for manufacturers to get their airplanes certificated as SLSA or ELSA, or for legacy airplanes to be considered "light sport aircraft".David wrote:Not totally following I am hovering really around 5175 - 5210 wot climb out. Cruise at 5500 level staying In the LSA 120 kts range, but can push it put to 5700 for 5 min which I don’t do. I think if I flatten the prob I will get more rpm on climb but less speed on top end. I’m happy with the climb I have it is outstanding.ShawnM wrote:I'd still correct the pitch issue you have as you can damage the engine if you are not careful.
Open for suggestions
Do you actually usually cruise at 5500rpm? I usually cruise at 5000-5400rpm and see 115-125KTAS. 5500rpm is 130KTAS or a hair more for me on a stock 100hp Rotax, but fuel consumption goes way up.David wrote:Correct i can push it up to 5700 ish at level flight for 5 min, but cruise at 5500 - i think it is dialed in, but i could bore wrong.3Dreaming wrote:
When he says he can push it to 5700 for 5 minutes I take that to mean 5700 is as fast as it will turn full throttle level flight.
True, but...MrMorden wrote:
There is no requirement for the pilot to maintain 120kt or less.
Partially true. 120 knots is the Vh limit. The definition of Vh (max horizontal speed) is very narrowly defined as:That is a requirement for manufacturers to get their airplanes certificated as SLSA or ELSA, or for legacy airplanes to be considered "light sport aircraft".
You'll never actually be able to test Vh under defined conditions, because even if you are at 15 C and 29.92, at sea level you'll be on the water, thus the humidity will not be zero!You cannot, however, make an alteration that takes the airplane out of LSA performance parameters. But unless you did calibrated sea level flight testing, how would you know?