Midget - K-40

Estes K-40 Midget Clone

Having acquired some vintage Estes short motors ("S" suffix), I decided to build a clone of the K-40 Midget to fly them in.

Here it is. The only modification was to extend the booster tube a little to allow an aft engine block to ensure positive separation when the sustainer lights.

And I can still fly it on T motors. They are easily adapted by inserting them into spent, sawed-off 18mm motor cases.

Flying it on T motors first was a good way to avoid the possibly higher risk of cato of the older S motors.

I really like the way it's turned out. The RustOleum red came out brilliant.

In this liftoff shot, you can just see the booster falling behind the head of the launch pad.

I cannot recall the circumstances. This could be either a catoing booster that managed to light the sustainer. Or it might have been an old, 1/2A shorty booster. Those tended to burn out very soon off the rod. Or it could have been an old, shorty motor catoing

I got in many good flights with the new K-40, but it seemed like every other time I looked at it, the motor tube appeared to be crooked. Given that the tube is only inserted 1" into the airframe, even a small imperfection in the centering rings can result in an off-axis alignment.

Regardless of the actual situation, I decided to build yet another K-40 clone. I used this one's nosecone and booster, and came up with this new, new K-40 at right.

Here's a good liftoff shot of the newest K-40.

And here's another good picture of it climing skyward.

And one more pic of the new K-40 lifting off from the pad.

12-25-2008