In the years I have been back in rocketry, and especially since becoming involved in high-power rocketry, I have noticed that rocketeers tend to build rockets the shape of which resembles the builder. At six foot three inches tall, I tend to favor long, skinny rockets. Binder Design’s Excel Plus matches my body shape.

The entire family of Excel rockets is inherently stable. The fin size is sufficient for stability, but small enough that the rocket does not weathercock excessively even in brisk breezes. My experience with the design began when I returned to rocketry at Whitakers, North Carolina in the Spring of 2003. The first version was a stock Excel, Jr., which was built and flown with the CP ahead of the CG. The first flight lasted about three seconds, which was how long it took the rocket to leave the launch rod powered by an F25 motor, turn a few back-flips, and slam into the ground breaking a fin.

Having learned a hard lesson on the importance of the CG-CP relationship, I moved up to the four inch Excel Plus. I built another stock version, but with a long altimeter bay to use dual deployment. I used this rocket to achieve Tripoli Level 2 certification in November of 2003 using a Cesaroni J285 motor. In December, I teamed up with Ed Rowe at Whitakers to fly a green flame EX motor. In a Senior moment, we cored the six 38mm grains to .375 inch. The nozzle throat was about .43 inch. The result was a classic example of an erosive burn, which destroyed the rocket in 1/100th of a second. The aftermath is shown below.

The destruction was nearly complete. The fins were shattered at the fin root; the motor casing was flared at both ends. The motors’ forward closure drove against the electronics bay bulkhead with enough force to crack the two layers of plywood, shatter the electronics sled, completely destroy the Missile Works RRC2, and disappear into the cow pasture. It has yet to be found. I salvaged the nosecone and the forward recovery components.

I built a second stock four inch version. This is shown in Figure 2 below.

The second Excel prepares to lift off on an Alan Whitmore six grain experimental I motor. The motor was retained by wrapping electrical tape around the motor casing and the giant leap retainer. At apogee, when the first ejection charge fired, the motor was ejected from the rocket and fell 3000 feet. Use positive motor retention to prevent this.

The first four inch Excel lasted only three flights. Two flights actually, if by flight is meant the rocket lifted off the pad under thrust. The second version is still in use and has about six flights with I and J motors.