Newcomers
32 Hollandbush Ct., St. Charles MO 63376
YEARS AGO I read a rather provocative piece in Reader's Digest. I can't remember the title, how long ago it was, or all of the details, but I do recall the basic thrust of the article; it concerned a fatal accident with a military jet.
The litany of the event listed a host of incidents, which led the author to the conclusion that the aircraft was destined to crash.
Although any one of the problems, or a departure from the original plans, would probably not have created the result, their accumulation created the destiny.
These items included a change in takeoff time, a point where the temperature created a marked change in density altitude at the airport, inaccurate runway distance markers because of construction, change in fuel load for a longer mission, and a number of other concurrent.
The result was a crash, and a pilot was killed.
Do you ever wonder how often modelers lose aircraft in much the same fashion? Those of us who have been flying models for any time at all could probably analyze one or more crashes and find an example.
The so-called "dumb thumbs" or "loss of proper neurological impulse control between the brain, eyes, and hands" could account for most.
Or maybe you witnessed the wing folding in flight or suffered a midair malady. Perhaps you attempted to outfly your capabilities—or the model's capabilities!
But how many times do little things accumulate during the building—and subsequent flying—and lead to problems? How often do you dismiss a crash as "bad luck" and continue to produce a chain of events leading to the crash of the next model as well?
Let's assume the loss of a model is through seemingly "unknown" causes, or at least unknown at the time of the crash. What's next?
- Pick up and save all the pieces. Take them home with you and conduct a study. Too often, because you are upset, the salvageable pieces are ripped out and the remaining scrap is tossed in the club trash can at the field.
In the process of doing this, you may have overlooked the cause.
Was it a broken clevis or pushrod? Did hinges pull out or fail? Was there a loose plug or wire? If you had taken everything home for a careful study, you might have found the problem.
- Did you build-in the "crash"? During construction, sometimes you substitute materials or methods. This is often done to save a trip to the hobby shop because you are in a hurry or because someone has suggested a "better way."
Your first impulse is that you know what you saw! In reality, you often see what you thought!
These changes often occur with mechanisms in place, which are ultimately hidden from view upon completion of the model.
Pushrods and their attendant hardware fit into this concern. Although it is true that broken pieces in the pushrod chain may be a result of the crash, sometimes you build in this problem. As models get larger, increasing strain is placed on such linkages.
The old "plastic" (nylon) clevis often isn't up to the job, especially if it isn't firmly anchored within the hole side of the clevis. Even a metal clevis can fall if the tabs are bent too far when opened for repeated installation.
Study the entire linkage chain.
Although you may have braced it well so it doesn't bend and you used hefty components for most of the chain, it's the one lightweight item that will fail.
- Reread the instruction manual. During the building or assembly process, you carefully read the instructions. (You did do that, didn't you?)
Now that you know something is wrong, check back through those instructions and compare the salvaged pieces to the directions.
Often, you are interrupted in the building process, and when you return to the project you overlook some small element. It may be as simple as not tightening a bolt or screw or forgetting to use Loctite® on the threads.
- For Radio Control (RC), check the system carefully. This one is a toughie! The first impulse is to check the radio.
After you determine that everything is plugged in, get the frequency-control pin and try to operate the system. If it doesn't work, systematically check the wires, plugs, and switch. By wiggling each of these, you may discover an open circuit.
Check the meter on the transmitter, the receiver antenna, battery packs—everything.
Do the batteries have an adequate charge? If the radio does work, there could still be problems. There could be low battery levels, a cracked crystal or circuit board, and other problems that give the appearance that everything is all right when it isn't!
- Collect anecdotal evidence from others who are watching your flight. It's amazing how many times you don't see the same things that a disinterested spectator might pick up on.
- Review earlier flights. The model will often have told you something was wrong or was going wrong well in advance of the problem. Changes in trim or a tendency to fly to the left or right, or noises and vibrations are also harbingers of doom!
- Get a second opinion. Although similar to getting spectators' opinions, this is slightly different. Have an experienced modeler look at the remains. It's amazing how you can overlook a problem or cause time and again.
- Think carefully about rebuilding.
- The problem that created the string of events leading to the crash may still be present in the restored aircraft! Now you've probably compounded it by coming up with a weaker, heavier, misaligned model.
- Save a piece! No matter what caused the demise of the model, save a remnant. Put it in a plastic bag and hang it by your workbench or stow it away in an identified "treasure" box. Hang onto it as a reminder of the incident.
Recently, as the start of a landing approach I was thinking, "Keep the speed up." That thought was still present in my mind, even through an altitude correction that bled off some of that speed—actually, too much! The result was a stall and a hard landing.
I didn't "see" the problem; however, others watching the landing did.
I have said it before: problems in machines do not heal themselves! If it's broken today, it will be "brokener" tomorrow!
It's like proofreading a letter; your mind made the mistake in the first place, and another pair of eyes can spot it.
Newcomers
so it simply continues to overlook it. A fresh approach often spots the problem.
Let that person also play the role of devil's advocate and ask the tough questions. If you are the person playing that role, don't be afraid to ask the simple questions. Assume that if you've been asked to help, the help will be gratefully received.
Often your impulse is to recreate the mythical Phoenix. That is a real possibility, but exercise with caution. Consider the nature of the damage and whether the necessary structural integrity will result.
You may also learn that it takes almost as much time and energy to put a wounded bird back in the air as it does to give birth to a new one!
Right before you go out to test-fly a new model, touch the plastic bag or box and recheck everything on the new model, including the mounting bolts on the engine and the clevis on the elevator, which I'm certain you forgot to tighten!
Now go forth and enjoy!
Cheers! MA
Transcribed from original scans by AI. Minor OCR errors may remain.
