John Martindale's KR2S

John Martindale's KR2S

updated Jan 23, 204 (added canopy and aileron pushrod pictures)

Hi folks. Well here it is...the first Corvair powered KR2 in Australia. This is the view at our Chapter 6 hangar in Coffs Harbour on the east coast. The aircraft is built to plan with the KR2 standard sized tail and fuselage.

Here it is inside the hangar. I used the "bambi" style of canopy. I guess it's named this way because of the two forward facing horns that take the hinge pins. Canopy frame and bubble are as supplied from Jeanette Rand. The usual tank area forward is now used for baggage as I have wing tanks instead. This has significant balance advantages because the CoG now moves slightly forward with fuel burn off rather than significantly backward.

A front view. She stands on fixed Diehl legs with Great Plains axles and disk brakes. Note how close the flaps are to the ground. I'll have to be careful here.

Here's the Corvair close up. Supplied converted and zero timed by William Wynne. Cost me $3500 Aust delivered. For comparison a Jabiru 6 here costs over $15,000. Ignition is dual Bosch automotive coils fed by two dual points through a MSD splitter on the high tension side.

Here's the exhaust. Simple straight down stacks, chromed on the lower 4 inches or so. The rear ones are slightly kinked sideways to clear the engine mount inside. I went this way so I can easily check the exhaust gas on each cylinder independently. Later, I may go with two 3 into 1 mufflers. Can't be bothered with balancing....too hard to built and I don't think at my revs there will be much improvement....time will tell however. The prop is 57" dia by 60" pitch, made from Queensland maple by Mick Dye, a local certified prop maker. Eventually I'll run with a 3 blade Warp drive but just ain't got the $$ for now.

A closer view of the canopy and cockpit. Note the canopy latches....simply a rod of 10mm aluminium that slides against a spring set in a tube inside the frame. A pin protrudes through the frame at right angles with a handle on each end and picks up the rod. Hope it doesn't leak too much.The ends of the rod lock into a hole drilled in the roll bar on the front of the turtle deck.

Here's the top of the Corvair..well packed to say the least! Carb is a Weber DCOE40 dual barrel blatently plagarised from Mark Langford. Forward of it in red is an intake plenum that has two KN air filters in each front side of it. The plenum is actually divided into two separate chambers feeding each crab venturi. Between the filters sits William's top mounted Toyota starter motor. The scat hose feeds in carb heat from each a box wrapped around each front pair of exhausts. Two butterflies on each side of the plenum switches between hot and cold air. The starter sits about 3/4" above a true top cowl line so there is a slight bulge in the nose (not shown in photo...I forgot to take it!!). Doesn't look too bad..sort of like a Collins class sub. Hope I don't forget to connect the throttle control cable. The spinner is chromed aluminium, 11 inch dia.

Nothing much new in this picture. Canopy actually opens a further 30 degrees but the wind blew it down as I took the photo. Might have to regas the struts a little more.

The fuel caps are chromed standard ones from an old HK holden. This car is like vegemite over can use it for anything. Tanks are vented from below via tubes a la Tony Bingelis. The instrument has separate switches and fuses but I'd recommend anyone to use combination switch/circuit breakers if for no other reason than the saving in wiring effort. The 3 1/8" blank hole is to take a turn coordinator but I'm tossing up whether to get a combination autopilot like a Century 1. In Australia to get anywhere you have to fly for a long time but I want to see how she handles first. The other hole takes a Radio Shack clock just to remain with certified stuff sic. The dag hanging down at the left is a 9 pin computer plug for the MAC servo on the elevator trim. How that thing can develop so much power on only 1 amp through such small wires is beyond me....Archimedes I guess.

Here's my upper cowl as promised. Looks a bit snub nosed due to the front starter but it grows on you.

The inlets measure 47 sq. inches in toto and the outlet underneath is 109 sq. inches making a ratio of 1:2.3 which is close to the recommended 1:2.5. Thorpe says to use about 0.35 sq. inches per HP so I'm hoping these are plenty big enough.

The cowl is held on by four piano hinges, two along each side and another two across the front. There are 6 brackets around the top rear that screw down with #8 pan head bolts. There is only about 1/2 inch clearance under the cowl so I'm hoping the engine doesn't jump up on the mounts too much. It would have to completely squash the bushes so I think I'm safe."

Folks, contact me anytime on the address below to talk more. May I convey special thanks to Mark Langford for taking the time to help me out both with this site and for all his other help at critical times..he'll know what I mean!! See Ya John.

Email John at

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