Hi all,
I have been trying to ascertain a safe cruising power configuration and also out how to get my GRT Hx to accurately read %HP. I have a Lycoming IO360M1B, Hartzell constant speed prop. I am using the Lycoming chart labeled Figure 3-26 in their manual. I would post if I could figure out how to do so.
The chart on the left says sea level performance. At 2700 RPM and 29" MP, you get 180 HP. If I go to 2300 RPM and 23" MP, the read off is 109 HP. I would assume that means I am developing 109/180=61% power at sea level.
Going to the other chart, altitude performance, 2300 RPM and 23" at 6500 feet reads 126 hp which should be 126/180=70% power.
I entered the numbers from the GRT chart for 0-360 engines and tried again with the numbers derived from the Lycoming chart for my engine model. Either way, I get an indication of 90+% power from the EFIS at 2300/23".
I am trying to figure out if I am reading these charts correctly. If so, cruising at 23 squared is pretty safe for my engine. It seems quite happy there and is giving me about 145 kt IAS, close to 160 TAS. If 2300/23" is really 93% power, that seems like a pretty high power setting for sustained cruise.
Can anyone tell me if I am in the right ballpark or is there some part of reading these charts that eludes me.
I have been trying to ascertain a safe cruising power configuration and also out how to get my GRT Hx to accurately read %HP. I have a Lycoming IO360M1B, Hartzell constant speed prop. I am using the Lycoming chart labeled Figure 3-26 in their manual. I would post if I could figure out how to do so.
The chart on the left says sea level performance. At 2700 RPM and 29" MP, you get 180 HP. If I go to 2300 RPM and 23" MP, the read off is 109 HP. I would assume that means I am developing 109/180=61% power at sea level.
Going to the other chart, altitude performance, 2300 RPM and 23" at 6500 feet reads 126 hp which should be 126/180=70% power.
I entered the numbers from the GRT chart for 0-360 engines and tried again with the numbers derived from the Lycoming chart for my engine model. Either way, I get an indication of 90+% power from the EFIS at 2300/23".
I am trying to figure out if I am reading these charts correctly. If so, cruising at 23 squared is pretty safe for my engine. It seems quite happy there and is giving me about 145 kt IAS, close to 160 TAS. If 2300/23" is really 93% power, that seems like a pretty high power setting for sustained cruise.
Can anyone tell me if I am in the right ballpark or is there some part of reading these charts that eludes me.