Kay C. Caldwell
  • Gunnison, UT
  • United States
Share on Facebook

Kay C. Caldwell's Friends

  • Scott Raynal
  • Ant Hudacek
  • Keal Bockelman
  • Cliff Hawrey
  • Paul Hajdu
  • Patrick Lee Martin
  • ben duarte
  • Craig Smith
  • Yvan Barge
  • Geoffrey Alexander
  • Brian Walker
  • James Cameron
  • Antonio  Gil
  • Ron D Leclerc

Kay C. Caldwell's Page

Latest Activity

A photo by Kay C. Caldwell was featured

CH 640 on dry lake bed

Fun with friends on a dry lake bed in Utah!!
Nov 20, 2019
Kay C. Caldwell posted photos
Nov 19, 2019

Profile Information

Aircraft Model
Project Status
Nearly done
Building From
Partial kit
Engine installed (or plan to install)
Building Experience
Have worked on airplanes before
Flying Experience
Private Pilot
Building and Flying Info / Your Profession / Other Background Info
composite construction in aerospace industry.

Kay C. Caldwell's Photos

  • Add Photos
  • View All

Kay C. Caldwell's Blog

ch 640

Posted on September 9, 2013 at 12:43pm 0 Comments

I finally ran some fuel through my project.  I am building a ch 640 from scratch.  I am using a subaru engine with an RFI redrive that I built also from scratch.  I bought a set of redrive plans from Don Parnham, and also had him do my computer harness etc.  It finally purrs like a kitten.  I ran it today for about an hour checking cooling, oil temp, redrive belt tracking etc.  It really lights the old building fire again.  Since I am building from scratch it has been horfically slow due to…


Comment Wall (13 comments)

You need to be a member of Zenith Aircraft Builders and Flyers to add comments!

Join Zenith Aircraft Builders and Flyers

At 7:02pm on May 13, 2020, Michael Hille said…

Hi Kay , since the video I have modified again not because it wasn’t working but to try and gain power all I did was remove the spring and ball to create a larger hole. I now have it set up through a catch can and breather and did away with sucking warm gasses into the engine as these gases contain less oxygen to help burn fuel and I picked up some HP.

At 6:05pm on August 1, 2017, Robert Audsley said…


Your plane looks Terrific, ecellent job.

At 9:36am on August 24, 2011, Brian Walker said…
Hi Kay - Do you have your CH640 in the air yet?  I'm slowly getting my fuselage built up.  Working on getting it on the landing gear now.  Let me know if you fly down my way!! Brian Walker - Las Vegas.
At 7:59am on November 16, 2010, Geoffrey Alexander said…
My goal is to have the airplane at OSH next year with all the details worked out. I also had to make the cowling bubbles bigger to clear the cylinders and plug wires. I will send you some more pictures.
At 7:54am on November 16, 2010, Geoffrey Alexander said…
Kay. I only have about 3 hours on the airplane so far. I seems very stable& holds altitude well in turns. I have trim (roll) issues still to work out. I almost changed out the aileron cables for push tubes before I put the wings on. Now I wish I had done this. I have the cables tensioned beyond the specs but still the left aileron will not stay faired in flight. It is OK on the ground. Must be some slop somewhere but I don't know how to fix it yet.
At 12:37pm on February 13, 2010, Kay C. Caldwell said…
I was hoping to have it in the air this summer but I don't know if that will happen. I am hanging the engine right now. I am using an auto conversion so it has been slower than I had hoped. Keep me posted on your progress. Thanks for the note. Kay C.
At 1:41pm on February 10, 2010, Brian Walker said…
Hey Kay. Haven't wrote in awhile. Do you have your CH640 flying yet?
At 12:50am on June 27, 2009, Antonio Gil said…
Hi Kay, the aircraft have the same performances that Zenair said,By the moment I am flying in 3000ft elevation airfield and with 65% -75% power
until 50hr.
The aircraft was showed in Paris (France) and I am very happy by its performances
At 3:51pm on June 26, 2009, Brian Walker said…
Jeff Paden's web site is no more. I've finished the rudder, HT, and both wings. Working on the fuselage now. How far along are you?
At 9:15am on June 26, 2009, Geoffrey Alexander said…
BTW Jeff Paden is crazy! Zenair will not even talk to him anymore.

New from Zenith:

Zenith Planes For Sale 

Classified listing for buying or selling your Zenith building or flying related stuff...

Custom Instrument Panels
for your Zenith

Custom instrument panels are now available directly from Zenith Aircraft Company exclusively for Zenith builders and owners. Pre-cut panel, Dynon and Garmin avionics, and more.

Zenith Homecoming Tee:

Zenair Floats

Flying On Your Own Wings:
A Complete Guide to Understanding Light Airplane Design, by Chris Heintz

Builder & Pilot Supplies:

Aircraft Insurance:


West Coast USA:

Pro Builder Assistance:


Transition training:

Lavion Aero

K&S Aviation Services

Aircraft Spruce & Specialty for all your building and pilot supplies!

How to videos from HomebuiltHELP.com

Developed specifically for Zenith builders (by a builder) these videos on DVD are a great help in building your own kit plane by providing practical hands-on construction information. Visit HomebuiltHelp.com for the latest DVD titles.

© 2024   Created by Zenith.Aero.   Powered by

Badges  |  Report an Issue  |  Terms of Service