How's my performance?

[Cfrisella]

I posted this on another tread but thought I'd start a new one to get some more opinions. I only have five hours so far on my 7A, but I'm suspecting I might need to have my prop repitched. Over the weekend I did get a chance to do the GPS box so you can see some initial numbers.

Specifics

Engine IO360 180 HP
Prop 3 blade Catto 64/77

Alt 8000
Oat 46F
Pressure 30.25
Man 22.2 ( anymore more and Rpms shoot past 2700. They'll go a over 2800)
Fuel flow *12gph ( still not sue if calibration is correct. Things to do)

Speeds are in knots
******************Indicated. **************Gps
N. ***************154. *********************154
E. ****************155. *********************164
S. ****************156. *********************194
W. ***************156. *********************176

Everything is painted, pants are on and three antennas hanging out. Hopefully someone with more experience crunching numbers can give some feedback.

Thanks!
---End Quote---

 

[kentb]

Chris, according to my spreadsheet.

Winds are 20.8 kts from 253 degrees and TAS of 172.6 kts.

Looks good, but you might want to get the prop governor adjusted so you can use full power without over-speeding the prop.

Kent

 

[Bob Axsom]

Agreed

I agree on repitching the fixed pitch prop to a higher pitch if you are going for top speed.

Bob Axsom

 

[LifeofReiley]

I'm almost positive Catto does not build a 64X77 three blade prop... unless it's brand new tech on his end.

 

[Cfrisella]

Good call Reiley! Just checked my paperwork again and you're right. It's a 66/74. I'm wondering what increase in speed I could anticipate with a prop adjustment. If it less then 7 knots I probably would pass and keep the extra climb.

 

[LifeofReiley]

Good call Reiley! Just checked my paperwork again and you're right. It's a 66/74. I'm wondering what increase in speed I could anticipate with a prop adjustment. If it less then 7 knots I probably would pass and keep the extra climb.

A 66X76 should gain you about 8 kts, BUT your climb will suffer some what. It depends on your misson. The 68" three blade I tested for Catto was BLAAAHHH. don't go there for sure.