The Bonner Specialties SN escapement was the most basic one and sold for $6.95. It used a torque
rod to activate the rudder.
Right: This O.S. compound escapement allowed
for a pushrod operation rather than the typical
torque rod. It sold for approximately $10.
This month, I will tell you about he early actuators that we used to guide our airplanes and keep them
from flying away.
Bringing the airplanes back to the
flying field where we had hand launched
them was our primary objective. In
those days, aerobatics was only for full-scale airplanes. Single channel meant
that only a single carrier wave signal
was transmitted by our transmitter.
That signal, after being received by
the receiver, allowed a coil on an
escapement to be actuated and move
the rudder. Yes, we flew with only
rudder control in those early days.
Today, escapement mechanisms
are found in pendulum or windup
clocks and were the basis for early
developers who built the first
escapements for radio control. In the
1940s, modelers had to make their
own escapements. I found articles
in Model Airplane News and in the
February 1950 issue of Flying Models
where escapements were mentioned,
advertisements for buying one.
J.S. Luck wrote a two-part article
for Model Airplane News (February
and March 1950) titled “Reliable
Escapements,” where he explained what
it took to build one. In Flying Models,
Walter A. Good and Gordon S. Light
explained, “The escapement is the
muscle which puts into action the signal
received by the brain.”
There was mention in those
magazines of an Aerotrol radio set, but
I could not find any advertisements for
escapements until March 1952. That
was when Berkeley announced its Super
Aerotrol system with a receiver for
$13.95, transmitter for $21.95, and an
escapement kit for $2.95. The magazine
ad contained a boldface statement:
“Flash!—License free after March 24,
Polk’s Hobbies advertised its
The Polk ad stated that the escapement
was 100% reliable.