Thorp Air Command - T18.net

Im posting this for Dan. I think he accidently emailed me rather than posting this to the board. So here goes.......


As a fairly new Thorp T-18C owner (about 50 hours), I'm excited to know this community exists for those of us just becoming familiar with the Thorp itself and the world of experimental aviation.

I figured I'd tap into the vast experience of folks that use this site to help me with a couple of questions.

-First, my O-290g has come to the end of it's useful life and I'm replacing it with an O-320. What are some issues that I need to be worried about with the change other than obvious things like W&B (she weighs 920 right now), mounts, accessories and the like?

-I currently run an AD wood 68''x66'' prop and she runs great, any advice on how that prop would match to the 320 or would a different prop be in order with the higher horsepower engine.

-I'm also in the market to upgrade from lap belts to a shoulder harness combo. What's a good place to anchor the shoulder harnesses and is there a specific brand/type that has worked well with your Thorp?

I really appreciate any and all input and look forward to hearing some good advice.

Thanks,

Dan Hildebrandt
N14GM
KMFR

Hooker Harness has made many Thorp seat belt and harness assemblies. I am on my second set (2500 hrs). My shoulder harness is attached to the front end of the rear canopy rails. These rails tie into several structural members. You could rivet straps to the under side of these and tie them further into the fuselage.

_________________
Bob Highley
N711SH
SN 835
KLAL

I got the "private message" from Dan too. Dan... your T-18C should have been built with shoulder harness attach points, as per plans. Are you saying it wasn't? Who was the builder?

A 68x66 Aymar-Demuth is not enough prop for an O-320. I run a 68x75 with my 160 hp O-320, & I feel that a 68x76 would also be very good with a little more cruise speed.

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John Evens
Arvada, Colorado
T-18 N71JE (sold)
Kitfox 7 SS N27JE

Hi Dan, I run an 0320 like John but mine is the 150HP version, 0320 e2D. I have a 68x72 from the late Michael Demuth god rest his soul. It offers good climb and cruise for this power plant, and the dry weight of the plane is 880lbs. God luck, the 320 is a good power plant for this airframe. Dan

I really appreciate the terrific advice from all that have responded to my "private message". Please forgive my ignorance as I meant to start a thread-not spam up everyone's inboxes.

To jrevins, the builder was a gentlemen by the name of Gary Morse. He finished her in 1984.

You'll like the 0320 over the 0290. A light 0290 powered airplane is a sweetheart, a light 0360 powered airplane is a beast, and 0320 powered airplane is "practical".

In all seriousness Ive flown xcountry with David Read in his 150 hp original airplane on many occasions. It's an honest 175 mph cruise airplane ... A 180 hp airplane will do 10+ more in cruise but burn 2-3 more gph. Not really worth the extra speed considering on a typical xcountry after 2 hours an 0320 powered airplane is 20 miles out when the 0360 machine is landing ... Heck by the time the first guy is unbuckling the second has touched down.

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Lee Walton
Houston, TX
N51863,N118LW
KEFD

Contact Paul Mcmichel 2535661971. He has a zero time O290 for 5000.00 cant beat that!