The Hawk and Vanguard from Laser-Cut Planes are designed for the new
P- 18 event. Flight times of 1 to 2 minutes are typical in a school gym.
Photos by John McGrath.
Grocery produce bags made from HDPE are
lightweight and are excellent, low-cost sources
for plastic film covering. The Turbo Cessna 195 No-Cal short kit from Volaré Products is a great way to get started in Indoor No-Cal.
The 2017-2018 Indoor Free Flight (FF) rules are currently available on the AMA website
and include a new event that was
passed by the Indoor FF Contest Board.
P- 18 (Event 227) is a provisional event
intended for newcomers with little to no
modeling experience who want to try
Quickly reading the adopted rules, the
P- 18 aircraft is defined as a monoplane
with a maximum wingspan of 18 inches
and a maximum chord of 4. 5 inches.
The stabilizer has a maximum wingspan
of 9 inches and a maximum chord of
3. 5 inches. The overall length is not to
exceed 18 inches and the maximum
hook-to-hook distance is 10 inches.
These rules are similar to Limited
Pennyplane, but P- 18 has a few
additional rules geared toward a
beginner. The minimum weight
without rubber is 7. 5 grams, and the
propeller must be an unmodified,
6-inch maximum diameter. The model
can also only be covered with tissue or
plastic shopping bag material.
The plastic shopping bag material
restriction might seem unusual at first,
but the plastic bags in the produce
section of grocery stores are quite thin
and actually weigh less than tissue
paper. The bags at my local grocery store
are 12 x 20 inches and approximately
2.05 grams per bag, which calculates
to 0.43 grams per 100 square inches—
comparable to lightweight condenser
paper and roughly half the weight of
After some research, I found the bags
are made by Inteplast and are 9 microns
thick. The 12 x 20-inch bags come in
rolls of 875 bags per roll and can be
bought from online retailers such as
Amazon or online restaurant suppliers.
This specific bag is sold in a case of
four rolls, which is 3,500 bags at a cost
of approximately $40/case, making each
bag slightly more than 1¢ each. At that
price, it is quite affordable for anyone
wanting to start flying Indoor FF. Yes,
3,500 bags is a lot of covering material,
but if you split a case with a few other
modeling buddies, you have enough
material for many years of building.
Other brands and sizes of produce
bags are available in single-roll quantities
from places such as Amazon. Just be
sure to verify the bag thickness when
you are searching. Bags such as this are
often measured in mils— 1 mil is .001-
inch thick or 25. 4 microns. You want
112 Model Aviation APRIL 2017 www.ModelAviation.com
New beginner AMA
event for Indoor FF
by Don Slusarczyk