1B90 Prop Re-Pitch for Climb

[Kerbs]

I have a 1B90 74/45 prop and would like to re-pitch it for better climb. From searching on here it seems like the ideal range is in the 42-43 pitch range. Does anyone have experience as to whether I should go with a 42 or 43? I currently have an a65 on the plane. Thanks!

[PA1195]

Hi Stu. Propeller overhaul shops generally suggest a result of 30-50 rpm per inch of pitch change. It can vary of course and depends on the propeller design and how it's been twisted along its length. That plus engine power air density and so on. To start maybe note your current static rpm then approach the maximum recommended in the Type Certificate Data Sheet A-696 (~2250 for the A-65 I think-maybe confirm) and WFO rated rpm ~2300 in cruise. Tachs are often inaccurate so maybe see if someone has a optical tach to calibrate yours or buy one (https://www.aircraftspruce.com/catal...es/trutach.php). My cable tach's accuracy varies with rpm so I stick the Trutach on so it can see the prop in flight.

Gary

[Robert Lees]

The 1B90 7445 Klip-Tip prop (in good condition) is the best prop for the A-65 powered Taylorcraft. In fact they are quite valuable, because they're not made in big batches*

You could sell that and get a Sensenich climb prop and be quids in.

*Pop quiz: Guess who makes Macauley fixed-ptch metal props?

[M Jones]

*Pop quiz: Guess who makes Macauley fixed-ptch metal props?

I know I know, but then I was with you on the factory tour...

[Guest]

The 1B90 7445 Klip-Tip prop (in good condition) is the best prop for the A-65 powered Taylorcraft. In fact they are quite valuable, because they're not made in big batches*

You could sell that and get a Sensenich climb prop and be quids in.

*Pop quiz: Guess who makes Macauley fixed-ptch metal props?

Apple?

[astjp2]

I am in on this posting...