Warringah
Radio Control
Society Incorporated (Incorporated under the Association Incorporation Act 1984) HOW TO LAND YOUR R/C TRAINER |
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It’s an old but true saying that take-offs are optional but landings are not. Yet nothing strikes terror into the hearts of R/C beginners as much as landings. This article may clear a few things up for you. However no article can replace the personal help of a qualified club instructor. Don’t fly alone - if you haven’t an instructor- find one. Then use what you read here in conjunction with your one-on-one training sessions to become truly proficent at landings. In what follows I will assume that you’ve been taking off and flying circuits competently but someone else has been doing your landings. Beginners reach this stage fairly quickly, but if you’re not there yet, just hold on to this article until you’re ready to attempt getting down on your own. At the field, be sure to do your usual through pre-flight check. You won’t get a chance to land correctly if your plane isn’t airworthy in the first place. Is the wing held on with at least six rubber bands? Check nuts and bolts for tightness, check that clevises are secure and have keepers fitted. Nosewheel/tailwheel in correct alignment with the rudder? Ensure the prop has no nicks or cracks and that the prop nut is tight. Are your TX and RX batteries fully charged? Be sure the wing and tail are firmly in place and in alignment. Range check your radio and that all control surfaces move freely, with the correct throws and in the proper directions with stick movements (the left aileron should go down and the right one up with right aileron stick movement). Most importantly do not fly unless everything is exactly right. A lost day of flying is better than an expensive and potentially dangerous accident which can “re-kit” your pride and joy or injure someone. Ready? Let’s go. Start your engine and check the idle and idle-to-full-open performance. Hold your aircraft’s nose vertically at full throttle and make sure the engine doesn’t sag. If it does, richen it up a few clicks then try again. Do not take off unless the engine performs flawlessly. At the same time as requesting take-off clearance from other flyers (you always do that, don’t you) tell them you’re going to be practicing landings, so they’ll know what you’re doing and be prepared to give you some time on the runway. For your first landing attempts, it’s better to fly when there are few other flyers to distract you, such as during the week or early on weekend mornings. Taxi out, line your plane up into the wind, one last check then take-off. Remember to do it smoothly. No jerking off the ground, just a nice gradual controlled climb-out and a smooth turn into the first leg of the field pattern. For the first few minutes practice flying circuits in front of you. Once you’re comfortable doing this try it at a lower throttle setting - say about half. Then back off the throttle even more. Keep doing this until you can fly level circuits at about 1/3rd throttle. Keep your banks shallow and your turns wide. If your trainer is trimmed and powered properly it should be able to fly level circuits at about 1/4 throttle without too much difficulty. Naturally it will require a bit more up elevator in the turns and in level flight, as well as more aileron movement than at faster speeds. One of the greatest problems beginners face is being able to fly their planes slow and being afraid to slow down enough to land. You cannot land at high throttle. You must do it at near idle. If you aren’t confident in handling your plane at low throttle, you will make your final approach too fast. The plane won’t settle properly and you’ll overshoot the runway, crash or execute a scary touch-and-go. So now you’ve got your level circuits at 1/3 throttle down pat, it’s time to consider the landing approach. At about 2/3 throttle, make your turn from the downwind leg and then on to “final”. If you’ve done it right you’ll still be at flying altitude, heading upwind over the centre line of the runway. Go round again and this time reduce throttle to about 1/2 and allow the plane to descend to an altitude of about 15 metres. Make your turns level and be as accurate as you can about lining the plane up with the centreline of the runway on “final” approach. Go round at 1/2 throttle again. Do this until you’re comfortable and your knees stop shaking. At this point it is important to remember the differences between controlling the aircraft when it is flying away from you versus flying towards you. Right stick always turns the aircraft towards its right - not yours. Therefore right stick turns the aircraft right when it is pointing away from you, but when it is pointing towards you right stick turns the aircraft to its right, which will be your left. It is absolutely essential to be able to control the aircraft when it is coming towards you in order to achieve a safe landing. Until control of the aircraft coming towards you becomes automatic - as it will in time - it may help to remember that to correct an unwanted bank, move the stick in the direction of the wing that’s down. OK, you’re at 1/2 throttle and holding. Now it’s time to really do it. Fly the downwind leg as before, staying level at about 15 metres. Make the turn on to the base leg and reduce throttle to 1/3, allowing the plane to descend gradually. Make a level turn on to final approach. You should be 50 to 100 metres away from the runway threshold and lined up with the centre line of the runway. If you are not, don’t try to correct things now, throttle up a bit, fly the field pattern and set up the approach again. When you are satisfied with your position coming out of the base leg turn, you are ready to begin your final descent to the runway. There is a tendency for beginners to overcontrol at this point. This is dangerous, because the aircraft has slowed down and is flying low. Overcontrolling may cause a stall from which it is impossible to recover. The key to success is to make only slight course corrections. When you’re lined up properly ease the throttle stick back to idle. Yes, idle. Hold in enough up elevator to control the descent attitude, pointing the nose of the plane at a spot on the runway centre line about 20 metres past the threshold. If the plane looks as if it is descending too rapidly and will fall short of the runway, briefly add a little throttle. Do not add any more up elevator than it takes to keep the aircraft pointing at that target spot on the runway and do not under any circumstances let the nose of the aircraft point up. If you do, you may cause it to stall, increasing the sink rate or worse still, the stall/spin/crash scenario. Keep the wings level by adding a little right or left aileron as required. If all is going as it should, your plane should be settling on a straight path towards the runway threshold. Soon it should cross the threshold at an altitude of about 3 metres, wings level, engine at idle, nose pointing slightly down, course centred and straight. If anything is a departure from that scenario, add throttle - not elevator - abort the approach, go round and try again. If all is well gently feed in some up elevator but not so much as to stop the descent. What you are trying for is a “flare” - a gentle change in the aircraft’s attitude with respect to the ground so that the main wheels touch the ground simultaneously with, or slightly behind the nosewheel (tricycle gear) or tailwheel (conventional gear). Too little elevator in the flare-out and the aircraft will hit the ground nose gear and prop first. Too much and it will stall, resulting in a hard landing or crash (remember the saying, “If it stalleth, it falleth!). Once on the ground, steering will be on the left (rudder) stick. Let your plane roll out straight and come to a stop. Take a deep breath. You did it! Several points are worthy of repetition. A well-designed, well built, adequately powered and correctly set up trainer will virtually settle in by itself if the approach is established properly. To do this it is necessary to ensure the aircraft is slowed down and flown smootly with no tendency to overcontrol. Right and left directions with the aircraft flying towards you must not be confused. Remember - push the aileron stick in the direction of the wing that’s down. Control of altitude is primarily by throttle, not by elevator. The elevator is used on final approach to aim the aircraft toward its approximate touchdown point and to produce landing flare. It is not used to make the aircraft go up or to “stretch the glide”. As your proficiency in setting up the final approach increases you will become less and less pressure during these final few moments of every flight. There will be more freedom to enjoy the beauty of your model as it crosses the threshold and gently finds the runway in safe, sure, and consistently well done landings. Happy landings!
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