I got a private email with one of the simplest questions anyone has asked me - yet I had never really thought to post - "So Paul, what kind of cruise performance/endurance do you find with different power settings?"
I am slightly embarrassed to say that while I collected tons of data during my phase 1, I have been so busy flying (and when not flying, working at the day job), that I have yet to build a lot of nice performance tables. And I have been so happy flying along at 8,000', wide open at 70% power and leaned out, that I really haven't used much else. But in answer to the question, I quickly dug out a few numbers, and I might as well share them with everyone. I just computed three conditions at 8,000', computing speed, endurance, and range. These are test numbers, without a lot of fine-tuning for DA, temperature, etc...but representative of what you can get in the real world. The RPM was set at 2500 for these three test points, and I can't tell you the MAP - I set my power by % on the EFIS (the MAP is in the records, I'm just too lazy tonight to pull them....). Endurance is absolute to dry tanks at 42 gallons.
8,000'
% HP = 70
TAS = 174 kts
FF = 8.5 gph
Endurance = 4.9 hours
Range = 860 miles
%HP = 60
TAS = 164 kts
FF = 7.3 gph
Endurance = 5.7 hours
Range = 943 miles
%HP = 50
TAS = 147 kts
FF = 6.3 gph
Endurance = 6.7 hours
Range = 980 miles
As usual, your mileage (and speed, endurance, etc...) will probably vary! I'm ready to stretch my legs after 3 hours anyway!
Paul
I am slightly embarrassed to say that while I collected tons of data during my phase 1, I have been so busy flying (and when not flying, working at the day job), that I have yet to build a lot of nice performance tables. And I have been so happy flying along at 8,000', wide open at 70% power and leaned out, that I really haven't used much else. But in answer to the question, I quickly dug out a few numbers, and I might as well share them with everyone. I just computed three conditions at 8,000', computing speed, endurance, and range. These are test numbers, without a lot of fine-tuning for DA, temperature, etc...but representative of what you can get in the real world. The RPM was set at 2500 for these three test points, and I can't tell you the MAP - I set my power by % on the EFIS (the MAP is in the records, I'm just too lazy tonight to pull them....). Endurance is absolute to dry tanks at 42 gallons.
8,000'
% HP = 70
TAS = 174 kts
FF = 8.5 gph
Endurance = 4.9 hours
Range = 860 miles
%HP = 60
TAS = 164 kts
FF = 7.3 gph
Endurance = 5.7 hours
Range = 943 miles
%HP = 50
TAS = 147 kts
FF = 6.3 gph
Endurance = 6.7 hours
Range = 980 miles
As usual, your mileage (and speed, endurance, etc...) will probably vary! I'm ready to stretch my legs after 3 hours anyway!
Paul
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