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Current Issue Ľ November 2013

ON THE SAFE SIDE

Airplane Restraints

by Jim Tiller, Insider Safety Column Editor
With this safety column Iíd like to stimulate a review of your clubís existing engine start procedures with an eye toward airplane restraints. At nearly all of the club sites I have visited, there is some type of apparatus for holding the airplane while starting the engine. It can be anything from a stake and a dog leash to specially designed tables. The most important issue is that your flying site does provide and maintain these important safety items.

 

In the August 2002 issue of Model Aviation, there were plans for a sturdy bench for starting airplanes. Many clubs have built one or more of these. The original design came from the Meroke Radio Control Club in Merrick, New York. If you want to download the original bench plan, a list of materials, or see many simple modifications and improvements, go to the club website: www.meroke.com/safetybench.htm.

 

These tables get your airplanes up to a more convenient height but the biggest asset is their inherent contribution to safe starting procedures.

 

My local club built eight of these tables years ago and we feel they have been an invaluable investment. We had a member donate the materials for a couple. The club put up the money for the rest. We built some bigger and some smaller to accommodate airplanes of varying sizes. We only had one problem with our tables. Since we live here in the Outback of the US, we had to modify the base to widen the stance. The originals kept blowing over in our South Dakota wind. Hereís our table design:

 

I think you can see in the picture that the table is well used, aged, but still serviceable.

 

There is a ľ-scale table with shortened legs shown on the Meroke website. However, many large airplane enthusiasts either find the tables too small or prefer to start their airplanes on the ground. Once again, you will find many ingenious restraint devices. Search the Web for tail restraints and youíll find several commercial offerings.

 

There are also many clever homemade airplane holders. At our field, one of the guys fabricated a simple but effective tail restraint that works very well.

 

 

It has a large metal stake that anchors it to the ground. The uprights have hinges on the bottom, so it is a simple matter of unhooking the bungee cord to drop the restraint to the sides.

 

There is some discussion about how safe tail restraints are compared to wing restraints. Some say the tails of certain airplanes are quite fragile. I donít have a definitive answer, but Iím sure the wings on most airplanes are more securely attached than the tail. If you want to go with wing restraints rather than tail restraints in a ground apparatus, hereís an idea:

 

 

In this design, metal pipes are driven in the ground and the two uprights fit down into those openings. To release the airplane, just pull them up, or drag the model backward.

 

If you are lacking in metal working and welding skills, hereís a tail restraint made largely of wood:

 

 

The base is made of hardwood. A steel spike fits through the middle opening and into the ground. The uprights could be substantial dowels for smaller airplanes or metal rods.

 

Airplane restraints are a safety device your club should not be without. However, it is just as important to have an assistant at engine start. We have all heard stories about what can happen if an airplane gets away from youóand only a few have happy endings. Plus, it is just common courtesy to offer to help a fellow modeler with his engine start and taxi. The pilotís focus should be on the airplane, radio, and engine. Help him with the other tasks at hand. There is no substitute for a second pair of hands and eyes while you start and fly your airplane.

 

With large airplanes, it is important for the airplane holder to know how to properly restrain the aircraft. In my flying group, the consensus is that you should hold the wing and the fuselage as shown here:

 

 

I donít think there is anything wrong with straddling the tail with your feet and holding the airplane between your legs, but it goes back to the tail restraint vs. wing restraint question. The wing is a stronger structural member.

 

Airplane restraints are not just for gas and glow airplanes. Electric airplanes should not be left unattended while they are being armed. I know most ESCs have an arming circuit designed to prevent accidental starts. Guns have a safety too, but all hunter safety courses teach you not to depend on it. The same should be true for us. An airplane restraint or a two-person starting procedure should be in place for electric operation as well.

 

Donít forget that all your engine tuning, removing the glow starter, etc., should be done from behind the propeller and not over it. But thatís probably another column.

 

Hopefully I have been singing to the choir here and your club already has a structured engine start procedure already in place. If you do, review it and consider changes that might make it easier and safer. If not, use this as an incentive to create one. Q


November 2013
Table of Contents

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President to President
Information Resources

On the Safe Side
Flightline Comnunication

Leader to Leader
National Model Aviation Day was a Success

Editor's Picks
Renewal Time

Know Your Site Owner's Policies

Six Keys to Success for New Pilots

Fuel: The Ins and Outs

Setting Up Your Servos

Eliminate Bounce in Your Landings

AMA Insider Archives Will Remain

Tips & Tricks

 

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