Safety Comes First
John Preston
Protecting R/C pilots
Protecting the R/C pilot was the first topic of discussion in the May 1987 Safety column. The discussion began with a conversation with J. R. Griffith, a committee member of the Austin, TX R/C club. His club installed concrete pads to serve as pilot flight boxes. Because the pads project about three inches above the surrounding ground, some out‑of‑control models sustained damage when colliding with them.
Several of J. R.'s modeling friends suggested adding dirt ramps around the concrete pads to prevent model damage. The problem with ramps is that they could cause a model to collide with a pilot's legs and possibly cause injury. I asked readers for their opinions and received an overwhelming response: all but one writer opposed adding dirt ramps. This was not surprising since the concrete pilot pads were described as being about 60 ft from the edge of the runway. A model running out of control 60 ft from its intended path may well suffer broken props or sheared landing gear; pilots should not have to worry about being struck while concentrating on flying.
Two letters describing pilot‑protection methods used by other clubs are worthy of note. One describes a grass flying field; the other a paved surface.
John Violette, secretary/treasurer of the Spillway R/C Club (Norco, LA), described a natural grass field that is part of a Corps of Engineers flood‑control system. He wrote: "What we have is a short‑grass runway and taxiway; elsewhere we have long grass three to four inches high to stop aircraft that may be temporarily out of control. What I would like to convey is the use of long grass as a natural barrier." Long grass provides automatic braking for errant models at minimal cost.
The Arizona Model Pilots Society (AMPS) flies from paved surfaces. James Trainor, AMPS secretary, recommended installing concrete parking‑lot bumpers to separate the runway from the pit area and to mark pilot boxes. The bumpers were installed after a runway model veered into the pit area following a hot landing and heavily damaged three other planes (two were reported to be of Scale Masters quality).
James reported: it has been a year since the bumpers went in; the club is still around, and the close calls have stopped. He knows of only one third‑order problem since installation, and there have been no reported injuries to pilots, pit people, or their planes. At least 50 planes have hit the bumpers (one was his), resulting in broken props and sheared landing gear—but no injuries to people. He also noted that pilots who might try to force a bad takeoff now prefer to shut down rather than risk hitting the bumpers.
I remain in favor of some means to protect pilots from ground‑borne models. Props and landing gear are cheap to replace compared with medical treatment. If your club's field doesn't already protect pilots on the flight line, consider making changes. Thanks to all who wrote in with opinions—without readers' letters this column wouldn't exist.
Pit etiquette
One correspondent elaborated on a pet peeve regarding running engines in the pits. D. J. Ottomeier (Albany, OR) said his club recently changed its rule about the direction a model must face while its engine is being tuned in the pit area. The old rule required models to face the pilot's field box and parking lot, with tails toward the active flight line. The logic was that thrown prop blades and runaway models would not threaten pilots in the airspace, and engine "goo" would not land on cars.
On the advice of an "expert," the rule was changed so models in the pits face the active pilots during engine run‑ups. The rationale was that the old rule exposed pit personnel to danger if a prop blade broke and was thrown off the crankshaft.
D. J.'s concern is that under the new rule the active pilots become the potential victims of thrown props and might inadvertently create a second hazard if they lose control of their models as a result. He asked readers to send their club's rule on running engines in the pits; responses will be discussed in a future column.
Heat-shrinkable film coverings
Until recently I would not have considered heat‑shrink film coverings hazardous. However, I received a letter from Debbie Watts, a modeler's wife and mother of a five‑year‑old, describing a near‑tragedy worth passing on—particularly to those with young children. Although Debbie named a particular brand, the hazard could apply to many brands. Her account follows in her words:
"My husband has been building R/C airplanes for the last three years. So my five‑year‑old daughter has grown up around the hobby.
"Recently we came close to having a disaster that could have been easily prevented. My daughter is very interested in her daddy's hobby, so he sometimes gives her scrap wood, etc., to play with. On this occasion he had given her a piece of heat‑shrink film covering to play with.
"One afternoon I was cooking supper when our little girl came into the kitchen. She had been trying to make a necklace out of the yellow film. The covering was wrapped tightly around her neck in a knot. Her face was already turning blue. I was unable to tear the covering off so I had to get a pair of scissors and cut it off. She had a red mark around her neck and a couple of small bruises. I hope this letter might prevent such a mishap from occurring again. The results could have been disastrous."
As someone whose regular job deals with the safety of children's products, I am well aware of hazards posed by strings and cords. I would not have foreseen the hazard of letting a young child play with a piece of shrink film. Please keep such materials away from small children.
Flight‑training programs
Previous Safety columns discussed benefits of formal flight‑training programs for new members with no prior R/C experience. I received letters from several clubs that run such programs, some enclosing copies of their flight instruction manuals. I particularly liked the program from John Chadd, who in 1986 was vice president of the Radio Control Aircraft Society (RCAS) of New South Wales, Australia.
RCAS developed a training program not primarily for safety, but to retain members. In 1980 the organization was concerned that more than 30% of new members lasted only one year before disappearing, often out of disillusionment caused by slow progress. The consensus was that improving club instruction would reduce the time required for a student to solo.
RCAS recognized it could not train every newcomer directly, but it could train the instructors. Together with one of Australia's most experienced instructors (also a full‑time instructor with the Royal Australian Air Force), RCAS devised a program to train instructors. The state body appointed chief flying instructors responsible for training club instructors; after trial, the scheme qualified additional chief instructors in NSW and was adopted by the Model Aeronautical Association of Australia. A formal instructor‑training program improves club instruction and helps retain newcomers.
IMAA safety guidelines
In the April Safety column I offered to mail copies of IMAA's safety guidelines to any reader who sent a request with an SASE. Joan Alyea, Safety Officer for IMAA, sent a copy of the 1986 revision, which I will send to requestors. I also have other safety materials available; please include an SASE for any requests. Available items include:
- R/C Preflight Inspection Checklists
- R/C Pylon Safety Checklist
- R/C Flying Field Rules (reprint of May 1980 Safety column)
Engine torque vs. P‑factor
In the January 1987 Safety column I published an account of a model crashing in a spectator area at a Quarter‑Scale Fly‑In (relayed by Henry Thomas via Bill Winter). Henry and I attributed the crash to uncorrected engine torque. Jim Ruley responded, claiming P‑factor was a more likely cause. I won't argue; qualified writers have discussed this (see "Torque Reaction" by Don Taylor, Letters to the Editor, Model Aviation, December 1986). Remember: when low and slow at high angle of attack, a sudden burst of throttle will usually roll the model to the left and require quick corrective input.
A second letter, from Dan Santich (editor of MAN), did not address torque or P‑factor but illustrated the kinetic energy of a flying model vividly. He wrote of a Pylon Race at the Winter Nats in the mid‑Seventies. After a heat, pilots shut down engines; one of four airplanes (a Cosmic Wind) landed fast, bounced, and headed for the crowd. Dan was in its path and described what followed:
"As it approached me I was struck with fear for life and limb, yet virtually helpless since there was no way to contemplate its direction. On top of that, there was nothing to hide behind!
"There was every doubt about the energy behind a five‑pound model airplane flying at 60 to 70 miles per hour; it was well defined in the ensuing event. Coming directly at me at a net of about seven feet, I put my hands up and caught it! It was a perfect catch. I felt the leading edge of the wing slam into my palms and watched in amazement as my feet left the ground. The force behind the model lifted me and propelled me backwards about five feet into the crowd, who caught me by breaking my fall. The model didn't have a scratch on it.
"While this story does not speak of torque as in the Thomas letter, it does relate to energy and motion. Our models are to be enjoyed for their grace and ability to please us. But they should also be respected for the potential to inflict grave injury. Like a pet lion, you can admire its beauty but should never take for granted its teeth."
Take Dan's experience as a reminder to respect the energy and momentum of model aircraft. Have a safe month.
John Preston 2812 Northampton St., N.W. Washington, DC 20015
Transcribed from original scans by AI. Minor OCR errors may remain.
