Thorp Air Command - T18.net

Anybody running a Bernie Warnke these days?

I'm not 100% confident in my Felix with the egged bushing holes, fretting, etc.... so thinking about plan B. A nice Warnke came up recently. 68x76 for 180 HP. Just wondering how that lines up with other folks installations and if they are happy with it.

Also wondering if maybe this is over-pitched since I have a de-rated engine. (168 HP)

Thoughts, opinions, lies, words of wisdom?

D

ZK-VMS T18C 150hp Lyc. Sensenich W66LM76 (been on aircraft for 20 yrs) urethane LE instead of brass. Static 2050-2100 rpm. 2000' FT 2700 = 165 Kts. Climb 1500'/min. Never tried anything else so don't know if good or bad! TAS @ 8 or 9000' 2650rpm=155Kts
Tony S

Hi all, Ira has a need for a Prop, he has a Sensich 66x74 wood prop it is a high dollar unit and very well made. He has a John Thorp 0-290with the 0-320 crank and this is not enough blade for this engine. We are looking for a Demuth, 68x72 or something comparable as this 290 turns the 66x74 without the benefit of a cruise speed, but it climbs like a homesick Angle. There is a list of components John listed in the logbook that he used to build this motor, it is very interesting and valuable information. It's kinda neat to have this piece of memorabilia withe the engine, and this little engine is a Hot Rod. Anyone having a prop to tame this little buger sing out, I am sure Ira will swing a deal with you gladly. Ira has never been able to post on this site, Lee can you give Ira a hand with this, if you remember I had a time myself as end wrenches are easy for me to use, but I am a ding bat when it comes to the electronic Marvels, anyone with a good blade sing out..........Dan

Hi, My Thorp is a T18C- 420kg- H2AD 160hp- Sensenich metal 70cm/79pitch. Cruise is 140kt/sealevel/2300/about 30Lts/hr. Bob Veale. Australia.

Could you post a pic of your motor mount. How did you do the top where the H2AD accessory case hump hits the standard T18 Dynafocal mount.

I hope your prop is not a cutdown 74DM.

FWIW 420KG=926lbs & 70CM=68"

Bob MO

Bob, I bent some cromeolly tube to go around behind the cam housing, then got it welded - to replace the old crossover piece - not a big job. Prop is an off the shelf from vans - suits an RV6. Bob V.

I tried a "new" prop Monday. Its a Performance 68x68, intended for a 150 or 160 HP RV-4. my son Peter got it with his RV-4 as a spare.
For me, with a stock T-18 'thin wing' O-290G with O-320E crank, Marvel MA4 and cheek cowl, I experienced a longer ground run and slower initial climb than the Ted Hendrickson 68x68 that I am refinishing.
The Hendrickson: Static 2250 RPM; 2600 RPM Max @ 179 TAS MPH 3000ft.
The Performance: Static 2160 RPM; 2580 RPM Max @ 177 TAS MPH 3000ft.
The Performance brand prop had increased to only 2200 RPM @ 120 IAS @ 1500ft MSL, but after that, the sluggish climb became a good climb as the speed increased, but still was a bit less than the Hendrickson. I don't fault the prop, as I said, it was for a more powerful O-320. The palm is wider in the working part of the blade than the Hedrickson.
What I did notice, is a harsh propeller beat, like the engine pulses are harder at the slightly lower RPM, not an out of ballance prop. Also, it tracks perfectly.
I believe it would serve very well on a dynafocal mounted O-320, but might run at full throttle above 2700 RPM, which is consistant with the RV-4s previous owner's statement. Something like it climbed great but was a bit slow at the top end.
This might be a great prop for a 150 HP RV-9, which Peter and his mom are building. So it looks like I'll have to give it back.

_________________
Scott Emery
EAA Chapter 326
T-18 N18TE

I'm very sorry that I mis-posted the prop in the above post.
Instead of "Performance" it's a "Props Inc" out of Neuport Oregon. They have a current web page, updated in January.
The particular Props Inc propeller I am trying is very old, probably built in the late 1980s. It still looks new. I would imagine that some improvements have been made over the years. I'll have to give them a call, maybe they make them run smoother or have a specific O-290 application.

_________________
Scott Emery
EAA Chapter 326
T-18 N18TE