Safety Comes First
John Preston 2812 Northampton St., N.W., Washington, DC 20015
This column is provided to address items of concern regarding safety aspects of model aviation activities. The content of the column, however, is the opinion of the author and does not necessarily represent the official position of the Academy of Model Aeronautics.
Topics
- Sailplane winch hazards
- Is safe flying just "No Accident"?
- Choosing a suitable RC trainer
- Ni-Cd battery safety
TRAINERS—basic, advanced, and beyond
Although there are about 450 people at my place of work, it seems that I am the only one who counts model aircraft as a hobby. As a result, in the weeks just prior to Christmas (I'm writing this column on January 2) I frequently am asked for my recommendations on what model to select for Uncle Charlie or Cousin Jack, etc. This year was no exception, since one of my co-workers sought my advice on a second model for his father-in-law. Last year I had been asked for my suggestion for a first model for this person, and had come up with a list which included:
- Goldberg Eaglet
- Sig Kadet
- PT-20 or PT-40
They chose the PT-40, and apparently the father-in-law was successful in learning to fly with this, his first RC model. Now I was being asked to choose something more challenging for a follow-up.
A number of years ago this column discussed at some length how to differentiate between a basic trainer and an advanced trainer. Some model kit manufacturers will tell you up-front in their advertisements which models in their product lines fit into each of those categories. However, there are others that, in my opinion, leave a lot to be desired when it comes to being honest in describing the skill level necessary to safely fly their products.
I've seen a number of newcomers to the hobby overestimate their talent in mastering controlled flight of a model aircraft. In a number of cases these individuals were full-scale pilots who believed that their abilities in the cockpit would enable them to skip the basic trainer when learning to fly an RC model. Big mistake. While the theory of flight taught to full-scale pilots is valuable for mastering RC flying, full-scale piloting abilities are not closely related to how soon someone will be comfortable flying a model.
I recall one full-scale pilot whom I tried to teach to fly RC models a number of years ago, who gave up because he couldn't master the skill. I have to place part of this blame on myself, because the model he chose as his first model was not really what I would now call a basic trainer and, at the time, I didn't see fit to try and change his mind.
It might be useful to publish an article that discusses the attributes necessary for a model to fit into the basic trainer category, together with a list of currently marketed kits that possess these characteristics. Similarly, the article could discuss advanced trainers and list appropriate kits. If anybody is aware of such an article having been published in the past, I'd appreciate a note with a reference to its whereabouts.
I do recall a lengthy letter to the editor of Model Aviation several years ago on this very topic. Its author offered to forward a list of his choice of trainers to anyone sending an SASE. At the time I did write for his list, but cannot now locate it in my files. Eight years of writing this column has resulted in a lot of material in the files, and I'm far from being the best at organizing it for easy retrieval.
Returning to the choice of a second model for my friend's father-in-law: initially I was handed a list of possible models that my friend's wife had gleaned from the pages of a Tower Hobbies catalog. I forget all the models on her list, but I do recall that one was a Tiporare (a competition Pattern model of the highest caliber), and the others were of a similar nature.
She had used as her guide the fact that her father was a good craftsman, and had stated that he wanted a sporty-looking, low-wing model, big enough to accommodate a .60 engine and capable of aerobatics. I hurriedly crossed the Tiporare off the list. No matter how skilled a person may be in controlling his first model, the jump from basic trainer to an all-out competition aerobatic model doesn't seem to me to be in the best interests of safety.
So, after going back to the Tower Hobbies catalog, the Radio Control Buyers Guide, and several other manufacturers' catalogs, I came up with another list from which a Goldberg Sky Tiger was ultimately chosen. I added the caveat that I had never built or flown this model, but it seemed to have all the desired features. I'll keep you posted on how the father-in-law fares with his second RC model.
Safe Flying Is No Accident
Several readers forwarded clippings from British model magazines, RCM&E, which concerned the collision between a hang glider and an RC sailplane that I used as the lead feature in the February 1988 column. I thank you all. One of these readers, James Ryan of Durham, NC, also included another clipping from Radio Modeller magazine. The editorial appeared to be by Roland Graunchet and was titled "Safe Flying Is No Accident."
In his opening paragraph Roland disagreed with the cliché. He stated, "A good expression, that, and one that I thought to be quite good until recently. However, I have been to a couple of meetings recently where there were two accidents—and very little safe flying, either." He went on to describe how "overweight models" were not flown in accordance with rules laid down by the British government, and questioned why foreign visitors to Britain were permitted to fly "in a criminally dangerous fashion and (can) get away with it," suggesting such behavior would be less likely if they were British subjects.
Roland cited an example of a model powered by twin pulse-jets and equipped with a gliding radio. Since the glides were producing a down elevator input, "the pilot had a brilliant idea—fly it upside down!" He concluded by asking whether, if the sport were not civilized, perhaps fliers should stop "behaving like boys with toys."
Here in the U.S.A. we have virtually no government regulations dictating how or what we can fly. We do, however, have certain AMA rules and recommendations. Many AMA members write these rules, and they can be changed through the AMA bylaw amendment procedure when the need is seen. For example, the Executive Council recently raised the minimum weight limit for free-flight and control-line models from 35 to 55 lb. to 100 lb. This decision is subject to subsequent approval as part of a set of requirements and guidelines to be produced by a joint AMA/IMAA committee. Whether you agree with this decision or not, the important point is that modelers with experience are establishing the rules which govern our hobby.
Whatever requirements and guidelines come out of the deliberations of this joint committee, it is up to us to follow them, lest we, like the British, suddenly find ourselves with government intervention in our hobby.
Another safety item appeared in the AMA News section of the February issue, in "A Note from the Technical Director" by Bob Underwood. This stems from an Executive Council decision and concerns creating a list of safety items for general model use. This list may include items that already appear in club flying-field rules, together with broader safety recommendations such as adjusting needle valves from behind the prop arc. Bob is asking for input regarding items that should be on this list. I will send Bob my suggestions and urge all of you to read his column and send him a note with your ideas. He also mentions that control-line and free-flight models are not included in the list; I think the list should be a broad set of model aircraft safety recommendations applicable to the largest number of AMA models (powered models and gliders).
Sailplane winch hazards
Last month I received a letter from Rich Madden of Anniston, AL, which began: "As a soaring pilot, I am one of those people that feel relatively safe in comparison to other forms of RC activity." Compared to being in close proximity to whirling props and models with top speeds near 100 mph, I feel pretty safe around sailplane flying activities. However, there is a potential hazard associated with sailplane flying in the form of the winch retrieval system. Rich described two incidents he experienced:
The first incident involved a runaway winch while he was on tow. The winch stuck immediately upon release of the plane and he realized it with his plane about 30 ft. up. He called to the winch tender, then pulled off the line. At that point he saw that there was no safety switch on the winch and that the winch was now taking in line at 2,000 ft./minute. Within seconds they were going to have 1,500 ft of winch line and 700 ft of retrieval line, complete with all leaders, ring, etc., all whirling around the winch drum; the tender was helpless to stop it. If he had had a wrench, he could not have reached the battery cables with all that line lying around. They were fortunate: Rich stomped the foot switch a couple of times and the system released—luckily it was not a stuck solenoid.
The second incident occurred as Rich tended a winch on only one retrieval. The system in use was the standard contest winch/retrieval system, except that the retriever switch was fitted to a winch drum brake handle. As he braked the winch drum with his right hand and reset the retriever to the "retrieve" mode with his left, he inadvertently touched that retriever switch. He received only some very minor line burns (don't depend on gloves here), but they spent 30 minutes getting the lines out of trees, etc. He also quit tending right there.
Let me summarize these incidents this way:
- DO NOT operate winches or retrievers without a safety switch in the electrical lead to the motor. To do so, even for sport flying, is inviting disaster.
- Any winch/retrieval system which allows operation of the retriever with the tender's hands in contact with the line is downright dangerous. Use a hand switch that the tender must pick up after resetting the retriever to the retrieve mode. A bump-start switch obtained from an auto parts store has worked very well for several years for some operators.
I don't think I need to add anything to Rich's account about the potential hazards associated with winches. I hope it's a safe month for everyone.
Ni-Cd batteries
A recent letter from California modeler Don Hughes inquired if any toxic gases are given off when Ni-Cd batteries are subjected to rapid charge or discharge. (Letter continued.)
Transcribed from original scans by AI. Minor OCR errors may remain.
