Radio Control: Sport-Aerobatics
Ron Van Putte
ONE TOPIC that has everyone buzzing lately is the potential loss of the 27-MHz frequencies to radio-controlled model use in an action proposed by FCC Docket #20120. The proposal includes revisions to current operating rules which would change the separate C and D classes to one class. In effect, this would preclude radio-controlled model aircraft flying on the 27-MHz band because Citizens' Band voice operation would be permitted on the five currently exclusive 27-MHz band Class C channels. We have enough interference already on 27-MHz with "exclusive" use of the five frequencies, so you can imagine how bad things would be if voice transmissions were allowed on our frequencies. I hope that you heard about the proposed FCC rule revision in time to write to your Congressman and Senators by the June 9th deadline for replying to the FCC.
Those of us who operate on the 72-75-MHz band shouldn't feel too cozy either. If the rule revision goes through, the 27-MHz fliers can be expected to join us on the 72-75-MHz band and make it just that much more difficult to have a chance to fly. In addition, the seven 72-75-MHz band frequencies which many of us have been assuming were exclusively allocated to radio control use are actually shared with many industrial and certain municipal users who often have very high-power transmitters (relative to our less than one watt power output). Many of us were surprised to discover that we were sharing the frequencies on our "exclusive" band since the FCC went so far as to designate four of the frequencies to model aircraft use only and three to shared use among airplanes, boats and cars. To me that implied no other uses were permitted, but that is not the case.
There are many stations licensed to operate on all of our 72-75-MHz frequencies. If you suspect that there may be some near you, a local FCC office will be able to help by identifying them, their operating frequency and the power output. If you are located near a military installation, there will probably be a frequency management office which will have the same information from the FCC. It might be very useful to place a couple of telephone calls; worst you would learn what the potentially dangerous frequencies were, at best you'd discover that you had no problems.
Discussions involving the effects of wind on aircraft continue unabated. The latest package of RC-oriented newsletters which the AMA forwarded to me contained a copy of the newsletter of the South African Assoc. of Radio Flyers from Johannesburg, South Africa. Their newsletter has a section called Opinions and Views which has apparently been used to conduct a running discussion (battle) on the subject of the effects of wind on aircraft. The author of one of the latest confrontations, Len Salter, has offered a reward of R100 (whatever that is) to anyone who can prove to him that an aircraft can "tell" if a steady wind is blowing. His recent article is a classic which I wish could be repeated here, but it is far too long. Let me include a few short excerpts which will give you an impression of the article (and the intensity of the discussion):
"You have probably heard it said that an aircraft has a better rate of climb into wind—nonsense; or an aircraft rolls better downwind than upwind—nonsense. If you don't believe me, prove it to yourself. Let us take three rolls, at your normal throttle setting, and at full aileron your setting gives you three rolls in five seconds downwind. At the same throttle setting, do them upwind and you will still complete them in five seconds. They will appear more compressed because you have covered far less ground upwind than downwind.
"You have probably all heard this classic when a stall turn has been fluffed, 'The wind blew it onto its back,' or, 'I could not pull out of the dive in time because I was going downwind.'
"Another age-old classic is this one, 'When I do a 180° turn from downwind into wind, my model always balloons.' If it does, it is because you made it balloon."
The newsletter from which I have excerpted the preceding contained no less than seven pages of assertions and counter assertions by two authors on the subject of wind effects on aircraft. Each author insisted that the other come to his senses and admit his errors. This hobby is a lot more controversial than outsiders could possibly imagine! By the way, I would be glad to provide copies of the articles if you would send me a stamped self-addressed envelope.
Let me change the subject by suggesting another RC racing event. You might be saying, "The last thing we need is another racing event!" or, "I thought Dave Lane was the Pylon racing contributing editor." However, we in Northwest Florida have started a racing event which is associated more with sport flying than it is with Pylon racing. It was started because of the unusual configuration of the Eglin AFB flying site. We fly from an inactive field on Eglin AFB. The field has three runways which form a large triangle. The distance around the triangle is approximately 1.7 miles.
Just imagine a team race several times around the triangle if the pilots flew from the back of a pickup truck or a convertible! An obvious problem would arise if the airplanes could outrun the vehicles carrying the pilots, so we decided to limit the speed of the airplanes by establishing gentlemen's competition ground rules as follows:
- Ace constant-chord wings—unmodified except for addition of ailerons.
- Cox Baby Bee .049 engine.
- No auxiliary fuel tank, just what is on the engine.
- Fuel with no greater than 15% nitromethane.
- Conventional landing gear with standard 1/4" wheels.
- 6-3 nylon or wood prop.
Not surprisingly, the object is to be the first to complete a certain number of laps around the race course. However, the races will be long enough so that several pit stops are required. We look forward to a lot of fun this summer competing in this low pressure racing event.
It's obvious that the kind of racing we intend to do is totally inappropriate for many flying sites around the country, but there are many flying fields which could have competitions similar to ours. You could even use a 1/4 Midget racing course and stand in one place instead of flying from a vehicle. The pit crew would get a lot of exercise if the airplane ran out of fuel at the other end of the course! You might like to give it a try because, although they were formulated to keep race speeds down, the rules will cause the cost of an airplane to be relatively low. Besides, you just might have a great time.
As this is being written, I'm preparing to attend my first pattern contest of 1976. Practicing the new Advanced pattern has caused a few changes in my initial attitudes toward several maneuvers. In the first place, the two-point roll is not as easy as I first thought. After practicing both maneuvers for a while now, I believe that the four-point roll is easier to do than the two-point roll.
Other observations are that I can perform spins reliably now and that the slow roll is much easier to do than I had feared. The main reason for this is that I installed two dual rate switches on my transmitter a couple of weeks ago. The transmitter now has dual rates on elevator and aileron. The low rate elevator is for normal flying; the high rate position gives me more elevator for doing spins. The high rate aileron is for normal flying; the low rate position gives me just the right amount of aileron for a slow roll. Now all I have to worry about is putting in the right amount of elevator and rudder control.
It was easy to install both dual rate systems by following the instructions which Jim Oddino included in his column in the November 1975 issue of Radio Control Modeler magazine. I purchased two toggle switches identical to the retract switch in my transmitter and obtained two sets of trim pots from Ace R/C: Catalog numbers 29K14 (10K) and 29K38 (4.7K). The total price for installing two dual rate switches came to less than $8. It worked for me and since I'm no electronic expert, it should work for you. Or maybe you can con the club electronic wizard into doing it for you.
If you are interested in the concept but would like to hear more about it, why not write to Model Aviation's Radio Technique contributing editor, George Myers, and encourage him to write a future column about it.
Let me close with a humorous contribution from Paul Harvey, one which he used in Paul Harvey News on April 9, 1976: "Telephone call to the Gary Fuller home in Juneau, Alaska, was answered by Fuller's daughter, age six. The caller asked, 'Is your daddy home?' She said, 'Daddy is out flying.' The caller asked, 'When will he be home?' She said, 'Not until he runs out of gas or crashes.' As she hung up... without explaining that daddy flies radio controlled miniature aircraft. The caller is still in shock." My address is: 12 Connie Dr., Shalimar, FL 32579.
Transcribed from original scans by AI. Minor OCR errors may remain.
