Safety Comes First
John Preston 2812 Northampton St., N.W., Washington, DC 20015
This column addresses items of concern regarding safety aspects of model aviation activities. The content is the opinion of the author and does not necessarily represent the official position of the Academy of Model Aeronautics.
"Safety Comes First" first appeared in the January 1980 issue of Model Aviation. This column completes my ninth year as a contributing editor, and I've decided to reveal myself by including a photograph.
My first column was typed on an old manual Olivetti portable machine. I still have that typewriter, but it's been retired to the attic. Since then I've used a Smith Corona electric followed by an IBM Selectric which, because it had a self-correct capability, I considered to be the ultimate typing machine until I gained access to a word processor. Although this latter electronic marvel does not use the same language as the computers employed by the magazine's editorial staff, with the help of a friend I recently figured out how to perform a translation that can be put onto a floppy disk and mailed to Model Aviation. The next step, if I can figure out how to do it, will be to send the column to MA via a modem. Today I wonder how I got by for so long with that old Olivetti that's now in the attic.
CyA glue
In the September 1988 issue I mentioned a warning notice that had appeared on a bulletin board in a major aircraft manufacturer's plant. The notice alleged that if you heat "super glue" to a temperature of 525°F the resulting hydrogen cyanide gas would be both 10 times the threshold limit and fatal. My column also stated that a chemist with whom I work did not believe this statement, and I asked if any readers could verify it.
After reading the September column, Dr. Jim Thomas, a chemist in the pharmaceutical research division of Parke-Davis, responded with some objective data. Jim's letter contained his calculations on how much cyanoacrylate (CyA) glue would have to be burned to reach the acceptable exposure limit (TLV — threshold limit value) of 10 ppm (parts per million) of hydrogen cyanide (HCN). His answer was that you would have to burn about 40 drops of glue, confine the resulting vapor in an enclosure with a volume of one cubic meter, and breathe that atmosphere for 10 minutes. In other words, the warning notice was not based on facts. Dr. Thomas' conclusions are based on facts, and (as stated in his letter):
"It is possible that burning a usual amount of cured CyA glue could cause an instantaneous exposure above the TLV, but not the 10 times the lethal dose noted in the article. The usual dissipation phenomena of diffusion and convection (since the burned CyA vapors would have to be hot) would reduce the local concentration of HCN very quickly, assuming a normally ventilated area. Also note that cyanosis is completely reversible, and (unless death occurs first) simply breathing uncontaminated air will reverse any symptoms of HCN poisoning."
In case anyone is wondering if there is a potential risk of HCN poisoning in the event that a whole bottle of CyA glue is burned, say in a house fire, forget it. There are many other things in your home that present a much greater risk of producing toxic fumes in the event of a fire — your sofa, if it has polyurethane foam stuffing, being just one of them.
Safety at fly-ins
A letter to the editor of Model Aviation was recently forwarded to my attention because it concerned some unsafe practices observed by Bob Benjamin, who had one of his models damaged in a very preventable incident. I'll let Bob's own words tell you his experiences.
My first surprise came when I presented one of my airplanes for safety inspection and was told not to worry about it, that this gathering was "just to have fun." As the flying began, I saw that no effort was made to have a "spotter," or safety man, accompany each pilot at the flight line. Although I realize that this practice is not specifically required, I believe that it is strongly recommended, especially in the case of large airplanes. It made me uncomfortable to see guest pilots, not familiar with the field, going out to fly alone. I also observed smoking on the flight line around gasoline-fueled models. I saw no effort to have this stopped.
The pit arrangement had the airplanes lined up in two facing rows along either side of a long taxiway. This by itself wasn't a problem, but it led to one. One member of the host club had been flying a Quadra-powered, Pitts-type biplane earlier, and had left me concerned that he did not have the model totally under control. While preparing to start one of my airplanes, I noticed that he too was getting ready to fly. I elected to wait until he had taken his turn rather than subject him to the distraction of another large, fast airplane in the air while he was flying.
Moments after I got up and walked away from my airplane, he started his engine—without a helper—and took off alone. The airplane climbed straight up and away to the left of the field. The airplane immediately went out of control, and I saw it hit the trees bordering the field about 100 yards away. The model came down in a wooded area and burst into flame. Thank goodness it fell away from the spectators. If it had come down on the taxiway, or into the pits, I feel sure that someone would have been killed.
A number of other incidents during the day were not as serious, but were only a matter of luck that no one was hurt. On other occasions I have seen pilots taxi across the flight line without calling "clear," and once I saw a pilot start his engine while another plane was on the runway. These are obviously little things, but I believe that a few common-sense rules would have prevented them.
After the dust had settled, a member of the host club told me that he had offered, moments before the accident, to hold the errant biplane, but had been refused. I think the conclusions to be drawn are obvious.
Perhaps the conclusions are obvious, but I'd like to make a few comments on Bob's experiences at the fly-in. First is the absence of a safety inspection of the models at the fly-in. Section V of the IMAA Safety Guidelines (1986 Revision) is titled "Safety Check" and states: "Before the first flight of each radio-controlled aircraft at an IMAA or IMAA/AMA-sanctioned event, it shall be inspected and approved for flight by safety inspectors designated by the Event Director, who shall use the then-current IMAA Safety Inspection Check Form in conducting such an inspection."
While conducting safety inspections of the models at the subject fly-in would not have prevented the accident that damaged Bob's model, failure to perform them doesn't reflect well on the organizers of the event. It also left them vulnerable to a lawsuit in the event that an accident did occur due to an "unsafe" model.
Bob mentioned that no effort was made at the fly-in to have the pilots be accompanied by spotters, a practice which he believes is "very strongly recommended, especially in the case of large airplanes." I would certainly recommend that pilots at any type of contest have someone accompany them to the flight line to act as an extra pair of eyes. However, this is not a requirement or recommendation in the IMAA Safety Guidelines.
In regard to the lack of a helper during the starting operation of the Pitts-type runway model, this could also be added as a recommendation in the IMAA safety guidelines. On the other hand, I have to question why the runway model's engine was being started in the pit area and not at the flight line. At most sanctioned RC events (contests), engine starting is performed at the flight line after a participant is called upon to fly. As an alternative to having a helper restrain the model during the engine starting operation, there are a number of "stogies" on the market that are an effective means to restrain models and prevent runaway accidents. I've mentioned several of these in previous columns, and I encourage their use for all RC models—big and small.
Fuel in the eye
A recent letter from Fred Randall of Canal Fulton, OH reminded me of the anguish experienced by well-known scale modeler Henry Haffke, who got an eyeful of glow fuel while attending a Giant Scale event in 1984. My February 1985 column described how it took four months for Henry's eye to get back to normal.
Fred's letter suggested that the risk of getting fuel in the eye may be higher for control-line fliers who use fuel bladders. These have been known to burst during refueling. However, it is not uncommon for fuel to squirt from a misplaced fuel line or a detached or broken fuel line. If you get fuel in your eye, you need to take immediate action. Fred says:
"The remedy is simple. Just buy a gallon jug of distilled water and a squeeze bottle with a long nozzle to squirt the water into the eye and flush it out. You don't know what's in some of the fuels; some of it could be harmful to the eye. We have a jug at our club and at contests, and it has been used several times. If the eye continues to bother you after flushing, see a physician."
Based on Henry Haffke's experience, flushing the eye as soon as possible and then seeking medical attention if irritation persists is the best course of action.
Strong Sailplanes
In last month's column I included excerpts from a letter I received from Rich Neveln who pointed out the hazard of pointed noses on sailplanes. This month I received another letter concerning the potential hazard of being struck by a sailplane. The letter, from Los Angeles modeler Shawn Heritage, stated:
"More radio-controlled glider pilots should be aware of the danger involved if someone is hit by one of these models. The construction of the models and the noses being built today is far stronger than those built in the past, due to the great proliferation and use of composite materials such as carbon fiber, Kevlar, and fiberglass. For example, when I was at the local slope-soaring site I observed an 8-ft.-span glider completely chop off an industrial irrigation sprinkler upon landing. The only damage done to the model was a small indentation in the leading edge of the wing, about the size of half a nickel. What would happen to a human body if hit by a glider at cruising speed?"
I don't think I need to add anything to Shawn's letter other than to say that I'd rather avoid being hit by any model flying at any speed.
Crash and burn
It isn't often that I receive a report of a model airplane catching fire after a crash. However, the July 1988 issue of Skywritings, newsletter of the Tracy Skyliners RC Club edited by Glenn Moore, described just such an incident. Fortunately, despite the very dry summer that most parts of the U.S. experienced, a brushfire did not result. The newsletter account, titled "F-16 Model Crash Results in Fire," was as follows:
"The crash of the F-16 ducted fan model almost ended in disaster when the model crashed into the field across the canal and burst into flames.
"The F-16, owned by Bill Grove, was on its first flight when the right stabilator broke off in flight. A weld joint failed, resulting in the failure of the stabilator joint. The aircraft then went into a dive and impacted in the field. Seconds later, smoke as well as flames could be seen rising from the field.
"As the black smoke grew in height, the Tracy Fire Department was notified about a possible grass fire. The Department sent one truck to take a look.
"Several club members went to the crash site armed with extinguishers to put out the blaze. When they arrived, most of the fire was out, with only fiberglass parts and engine remains still smoldering. Luckily, the surrounding dry grass had not been ignited. The entire plane was destroyed, and the radio equipment had melted. The fuel tank had split apart and fed the blaze with 15% nitro fuel.
"All club members should take precaution when a plane goes down into the field in this dry weather. Extinguishers are kept in the transmitter impound for such emergencies."
Transcribed from original scans by AI. Minor OCR errors may remain.
