K & S Duration Rules
Devised by Alan Estenson
Last revised October 10, 1998
Explanation: When MASA first formed, I thought
that it would be neat to have some contests at our launches.
However, nearly all MASA members (including myself) have never
participated in an official NAR competition. So, I invented
these rules for a fun, informal, slightly wacky competition that
could be done at any launch.
If you walk into your local hobby store, they
probably have a rack of "K&S" brand products:
steel "music" wire, brass tube, brass rod, etc.
These products are in red cardboard tubes, three feet long.
Since I work in a hobby store, I have a ready supply of these empty
tubes. My thought was: "Why not invent a
competition where you're required to build a rocket out of one of
these things?" Admittedly, the tubes are quite
thick-walled and heavy, but that's all right, we're not going for
high performance.. For MASA members, I can supply with a tube
upon request. For anyone else reading these rules, look to see
if your local hobby store has an empty tube in its rack.
Please, ask them if its okay before you take it.
Obviously, K&S has nothing to do with this thing
other than being the unwitting supplier of the primary component.
Important hint: remove the red outer layer of
the tube where fins and such are glued. Under the rules, you
have to leave it everywhere else.
The current "official" longest duration in
the "C" motor class is 47 seconds (Art Gibbens, 7/26/98)
The "unofficial" longest duration in the same class is one
minute, 2 seconds (Alan Estenson, 7/26/98)
A K&S "lawn dart" has a typical
duration of about 11 seconds. <grin>
All aspects of the United States Model Rocket Sporting Code (NAR
"Pink" Book) apply save where abridged by this document.
The NAR Safety Code shall stand in all respects. (duh!)
K&S Duration Competitions
Consist of a single division covering all age groups.
Each competing person will be allowed a maximum of two (2)
flights in each category during a "formal" competition.
During an "informal" competition, each person is
allowed to fly as many times as desired with the winner having the
longest single flight of the day.
Timing and scoring will be performed in the manner described in
the "Pink" Book.
All motor cases must be retained in the rocket. Failure to
retain all motor casings will result in disqualification of the
The primary component of the rocket will be a 36" red
The nose cone and fins may be of any style and materials allowed
under the NAR Safety Code.
For each engine, a 3" length of BT-20 (or equivalent) tube
may be used as a motor mount. This is the only type and usage of
tubing allowed other than the K&S tube.
Paper, light cardboard, and balsa wood are permitted for such
purposes as fairings, shrouds, adapters, boat-tails, fins,
centering rings, decoration, etc. These materials may not be used
to form body tube segments. (A body tube segment is defined as a
cylinder of approximately constant radius that is more than
0.5" in length.)
- A combined minimum length of 34" of an original K&S
tube must be used in each rocket. No more than one tube
(36" in length) may be used in a rocket.
- The K&S tube must retain its original red coloration (no
paint is allowed on the tube other than a clear coat.)
- The original K&S label must remain on the tube and be
visible on the finished rocket.
- A baseline K&S tube has a weight of approximately 2.6
ounces. Therefore, no rocket in these competitions shall weigh
less than 2.6 ounces (without motors).
"C" Motor Class, Single Motor, Single Stage, Duration
- Any number and size of parachutes permitted.
- Any number and size of streamers permitted. (As limited by the
- (Excerpt from 31.2) A streamer is defined for this event as a
piece of cloth, plastic film, or paper, whose shape is
approximately rectangular. The streamer must have a
length-to-width ratio of five to one (5:1) or greater… The
streamer and model must be connected by only a single line or
cord, attached at the narrow end of the streamer. The cord may not
be connected to either the streamer or the model at more than one
point.. The streamer may not be cut, slit, or otherwise altered in
such a manner as to affect its nature as a simple connected plane.
- Maximum rocket weight (without motor) of six (6) ounces.
"B" Motor Class, Clustered, Staged, Duration
- Parachute and streamer regulations shall be identical to those
described in the single motor class.
- The model shall have a minimum of two (2) motors and a maximum
of six (6) motors.
- If the model is staged, each stage must have a minimum of two
- No model shall have more than three (3) stages.
- (23.6) Air start of motors using any safe method is specifically
permitted. A model igniting one or more motors which serve to
ignite an additional motor or motors is permitted.
- (23.7) Models that do not ignite all motors in flight will be
considered official flights. An entry which fails to ignite all of
its motors is considered a qualified flight unless it is unsafe,
experiences a catastrophic failure, or is lost to sight.
- Maximum rocket weight (without motor) of twelve (12) ounces.