For this issue I am going to FLAP at you, only because I do not see flaps being used enough on our big, beautiful aircraft. Flaps are wonderful! If installed properly, flaps can be one of the most rewarding items that your aircraft can have. Let's get right to it!

Flaps react quite differently, aerodynamically depending on the type of aircraft they are on. One thing is certain, flaps act as spoilers, flaps can act as extra lift, and flaps can create problems. Flaps can also create washout where there is none. Flaps are also misunderstood by many giant scale modelers, therefore let us review what I have learned about flaps in a general way so that you can understand how to install flaps and get the most enjoyment and results from being able to use them.

Although I have had flaps on at least four large aircraft, each flap situation created some "new" findings. For instance, on my hugh 12' span B-25, the flaps at half-flap created much lift, whereas at full "down" deflection the flaps created a heavy drag and very little lift, and at the same time created a tremendous amount of wing washout due to the altered angle of attack being created. When deploying flaps, NEVER deploy them while the aircraft is flying at high speed! You stand a chance of tearing the flaps off and possibly doing some serious servo and structural damage to your aircraft.

Also, keep in mind that you should have one servo for each flap, especially where the model has four large flaps. Install a servo just ahead of each flap, centered. Where there are only two flaps, a single heavy duty servo such as the Futaba S-34, Eagle II by EMS, or World S-16 can be employed. The shorter the linkage from flap to servo arm, the better.

Flaps should be made from a 5-ply aircraft grade plywood, 1/8 inch think and ribbed on the inside for extra strength. You would not believe the amount of G forces that hit flaps! Are you ready for this? Up to 12 G's and more are tugging on the flaps of some giant scale aircraft! Scary, isn't it? That is why it is especially important to deploy flaps at less than half throttle and only on your final landing leg, after the crosswind leg ready for set up and landing approach. Modelers that know how to use flaps have learned how to do so from modelers that are or have been full-scale pilots.

Basically, this is how to use flaps:
For the first time out for a new model that has full flaps, NEVER use the flaps on the very first take off and test flight. If you do, you are courting disaster! You have no way of knowing what effect the flaps will have on your model, nor do you know how much flap deflection to use for correct benefit to the aerodynamics of your aircraft. You must first fly the model, trim it out to perfection, then fly the model until you feel comfortable with its flight characteristics. Once you feel comfortable with the way the plane flies and handles, you are ready for stress maneuvers and flap landings.

Do it this way:
Take the aircraft up to approximately 300 feet (about three crashes high), point it into the wind, reduce throttle to 1/3 (no more, please!) and if you are not too nervous, add approximiately 1/4 flaps and see what will happen. Will the aircraft Balloon too much? Will it want to fall out of the sky? Will it act lazy and squirrely? If so, add a tad more throttle and some "down" elevator and the model will probably smooth out and behave.

Once you have the plane under control and still facing into the wind, add flaps to half deflection and check the results. At this point you may be totally amazed at how much "down" elevator you will need just to keep the aircraft flying straight and level. Now, put the flaps back up and go around for another try at flap learning, into the wind, please. NEVER add flaps flying downwind. The airplane will practically fall out of the sky, snap roll, tip stall, and scare the heck out of you!

Okay, now you are heading into the wind again at 1/3 throttle. Add full flaps, FULL DOWN deflection. Remembering that you had to add a lot of down elevator, add a lot of down elevator at the same time that you add the full down flaps. The model will slow down very drastically and you will feel as though you have almost full down elevator just to keep the nose level, and that is precisely what the aircraft SHOULD be doing. From this point on, you have overcome the fear of the unknown and are ready for seeing exactly what the flaps can do for your model and your nerves.

Here we go:
From 250 to 300 feet, aim the model at the runway at straight and level flight, at 1/3 throttle, from a point approximately 2000 feet to your right assuming that you will be landing from right to left, east to west. As you begin to point the nose of your aircraft down at a 45 degree angle, you add full flaps, NO LESS. You will see a sight so rewarding that everyone watching will ooh and aah. Your aircraft will literally float down at 45 degrees at 1/3 throttle, using a lot of down elevator. When the model gets closer to the actual landing area, you might have to increase engine throttle in order to maintain a smooth, steady landing approach, and you'll find it very interesting to see that the model behaves like a J-3 Cub, won't tip stall, and will land like an American Eagle pursuing a field mouse. Landings can be made in relatively short fields. The more you practice with flaps, the more you will realize that flaps are a necessary function of almost every airplane ever made. No reason why our giant scale models should not have flaps.

Some fellows get into trouble by adding too much flaps on take off, especially on windy days. Never use flaps on take off on a windy day. Your aircraft will not need the extra lift, and we normally use gas engines that have 30 percent more power than we need. If you want to experiment using flaps on take off, do so on a calm day, and begin by using 10 degrees or less of flap deflection on the first attempt. Increase by 5 degrees at each take off and note the effect that amount has on the ability of the model to track out. I once saw a beautiful Nosen P-51 crash on take off due to its owner not understanding flap deflection on take off. He added full flaps, hit the throttle, the P-51 ran out about 20 feet, then lifted off, went Straight up due to the extremely high lift condition that the flaps created, and then fell over and left one very admirable hole in the runway. All this happens in approximately 2-3 seconds, so beware! Take your flap routine a little at a time, be sure to keep the plane moving but not too fast, and you'll soon learn what flaps can and cannot do for your and your precious giant scale bird.