Safety Comes First!
An RC tip: Transmitter discipline at the flying field is a keystone of safe operations.
John Preston
With the appearance of this column, we will have completed our first year as a contributing editor to Model Aviation. When we sat down at the typewriter for the first time, we wondered how we were going to find the material to fill up these pages. Fortunately, the response from our readers has been terrific, and our only problem in meeting our monthly deadline has been in finding the necessary time to sit down and edit our correspondence into a column of reasonable length. We are ashamed to admit that some of you have not received personal responses to your letters. We apologize. We also thank you, for without your mail there would be no safety column.
This is being written in August. A busy month. We recently returned from the Nationals, where most of Model Aviation's contributors will have picked up the material for their articles in this issue. We are happy to report that this writer saw no incidents involving safety that are worthy of special mention. We did see a rather large number of Scale models reach the end of their lives, many because of a breakdown in the communication between the RC transmitter and the receiver. Whether this was due to external interference or to internal radio problems, we will probably never know. The scanners that were in use throughout the flying portion of the RC Scale events never picked up any recognizable interference. However, during many flights, models were as much as 1,000 ft. distant and 400 ft. above the scanners. So, who knows what the receiver was picking up.
Since it appeared to be problems induced by radio malfunction that were responsible for many Nats crashes, and since I had just returned from the local flying field where I was unable to take photographs of a new model belonging to a friend because radio failure put it in a tree before I arrived, perhaps a discussion of radio interference is in order for this month's safety topic.
We doubt that there are many RC clubs of any appreciable size that don't have some form of frequency control at their flying fields. The most common system uses a color-coded clothespin which must be in one's possession prior to turning on one's transmitter. While this method works well most of the time, it relies on the self-discipline of each and every member of the club to make it work. Most of us, sooner or later, are going to have a lapse of memory and turn on a transmitter before gaining possession of that all-important clothespin. Perhaps we should ask ourselves whether there is something else we can do to prevent this lapse from occurring. We think there is, but first let's look at some incidents which have happened that have involved frequency conflicts.
The following account comes from the newsletter of the Staten Island Modelers: "I really did it, fellas! I broke the cardinal rule of RC flying. While practicing landing approaches, I zigged when I should have zagged, and the ground came up and hit my plane. I placed my transmitter on the ground near my flight box and walked across the field to retrieve my bird. I came back to the flight line, took the frequency pin off, collapsed the antenna, and placed my transmitter back in the impound area. I never checked the transmitter to see if it was off. It wasn't. As a result, I shot down a Kougar. Luckily for me, it was just after takeoff, and the plane was not severely damaged. Moral of the story: when you take the frequency pin off your transmitter, check, double check, and check again: make sure it is turned off! Believe me, it's a rotten feeling knowing you're responsible for damaging someone's equipment."
In that story, a flier's normal routine was altered by his landing accident. Presumably, not being able to taxi the model off the runway, the flier left the transmitter until he retrieved his model and was able to turn off the receiver. However, on returning to the pit area, turning off the transmitter was forgotten. Although this flier blames himself for the subsequent shootdown, in our opinion the flier of the shot-down model should also shoulder some of the blame. Why, you might ask? If you reread the account, you will notice that a transmitter impound area was in use. We are firm believers in such a practice because it puts all the transmitters at the flying field in one place, and before taking one's own transmitter for a flight session, one can easily check to see if another transmitter on the same frequency has been left on. In the described incident, this was not done.
For good measure, we have another frequency conflict story that comes from "Hear Ye," newsletter of the Valley Forge Signal Seekers, Brent Sickles, editor. This club regularly features a Safety Board Report in its newsletter. Perhaps others should take heed and follow suit. Here is the story: "Conditions: Clear weather, 8–10 fliers at the field, 2–3 spectators, wind west. Flier A was set up at the east end of the field, and had just finished flying. Flier B arrived and set up at the west end. B got the correct frequency pin and started his engine. He was taxiing to the east end of the field to take off when the airplane went out of control, turned right, and went into the group of fliers around A.
"Reason: Flier A (on the same frequency as Flier B) had left his transmitter on, so that while B's plane was in the vicinity of his own transmitter, there seemed to be nothing wrong, but while taxiing B's signal got weaker while A's signal got relatively stronger and caused the interference. Ironically, the plane actually hit Flier A. Luckily, he was not seriously injured, but it really hurt, and it could have been much worse."
I wonder who our readers would have blamed for this accident? The VFSS Safety Board Report blamed both Flier A for leaving his transmitter on and Flier B for not checking the flightline for others on his frequency to make sure no one else was turned on, which is not an easy job at a crowded flying field unless a transmitter impound area is being used. The report also cited that such was the case.
So how do we prevent incidents of the type just described? Again, we turn to a club's newsletter for the answer. This time "The Slipstream," newsletter of the Tri City Aeromodelers, editors L. C. Daniels and Tommy Ward. This safety tip was presented at their May club meeting: "To check for radio interference, turn on transmitter and receiver, move all controls to one extreme, then turn off transmitter. If there is no interference, the control surfaces on the airplane should remain stationary. If a radio on the same frequency is left on with its controls in the neutral positions, the control surfaces of the airplane will return to neutral."
How's that for a simple check? We generally turn on the receiver before turning on the transmitter, but this practice is aimed at preventing our transmitter from shooting down another flier's model. It doesn't tell us that there is another transmitter with all controls at neutral sitting in someone's field box.
For the most part, the simple frequency clip (clothespin) provides protection against frequency conflicts. A transmitter impound adds a measurable amount of additional protection. If, on top of these two procedures, we add the turn-on/check/turn-off routine, we will never again either shoot down or be shot down. Correct? (No, I'm really not that naive, just an optimist.)
To end the column this month, we would like to throw some limelight onto those ever-popular contest officials—the judges. Maybe you've never considered a judge's job to be hazardous. Although we opened by saying that no safety-related incidents were observed at the Nats, we forgot about the extremely rapid evacuation of their chairs on the part of five judges as one of the RC Scale flight lines commenced. Two of these gallant fellows failed to escape and were actually struck by a model which, for some unaccountable reason, veered off the runway during a takeoff and ran full-bore into the judges. Fortunately, it was a pusher, and only minor bruises resulted. I'm sure all Scale contestants have, at one time or another, received static scores that were less than enchanting. However, this is no reason to resile revenge on the flight line. Flight judges don't like to get scared, and when they are forced to leave their chairs, they have a habit of drawing little circles on the score sheets. Have a care for these fellows. They generally do a great job.
John Preston 7012 Elvira Court Falls Church, VA 22042
Transcribed from original scans by AI. Minor OCR errors may remain.
