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Old 04-28-2002 | 08:33 AM
  #13  
HarryC
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Default Tail dragger setup

Bo, two of the people I am teaching at the moment are having the same problem as you, bashing the model in nosewheel first every time. I keep demonstrating how the model should be nose high on landing, how and when to pull back on the stick. When they are landing I tell them "pull back now, NOW" but they still don't do it and whack the noseleg in again. Changing to a taildragger will not solve this because if you are not pulling the nose up, where the wheel is will have no effect. In frustration I have tried a new flying exercise on them which seems to be helping them become more comfortable with pulling hard back to land as trainers need, and their final flare-outs have improved quickly. Fly around at safe height, slow speed at full up elevator - their Thunder Tiger trainer flies quite happily like this without stalling out. It has got them used to and comfy with holding on lots of up elevator and still steering the model, so when they come to the final flare for landing they are used to how it feels to pull hard back on the stick.

Ignore anything about mixing aileron to rudder for co-ordinated turns because it is mostly wrong. Your trainer should not need co-ordinating and if it does need a bit, who cares anyway, there is no-one on board to feel ill. Mixing aileron to rudder only works while you are holding on some aileron and unless your trainer is so ridiculously stable that it keeps trying to roll upright immediately, you will not be holding on any appreciable amount of aileron in the turn. Ailerons can cause an affect called adverse yaw, where you roll one way but the plane yaws the other way, this is worst in gliders which have long spans and hence plenty of leverage to cause the yaw. The effect only happens whilst some aileron is applied, once you achieve the desired bank angle and neutralise the ailerons, the adverse yaw disappears. In this case a small amount of rudder mixed from the aileron can counter the adverse yaw, but this only works during the roll into and roll out of the turn. It can have no effect during the turn where the ailerons are at neutral. It is simply impossible for aileron to rudder mixing to balance a turn since you don't hold on a big enough amount of aileron in the turn to make the rudder move! Should the plane be obviously out of balance during the turn, and you really feel the need to correct it, you will need to use your rudder thumb. Frankly it is not something you need to bother about at this stage.

An aircraft may yaw slightly out of or into the turn, this is called respectively slipping and skidding. Which it does depends upon the speed, the angle of bank, the power setting, the design and so on. In one turn it may slip, in a different turn it may skid. The first needs rudder into the turn, the latter needs rudder out of the turn. Since mixing will only give rudder one way, it can not be of use since it may move the rudder the wrong way for that turn! Only model fliers believe that rudder must be the same way as the turn, full size pilots have a slip ball instrument that shows them which way to move the rudder and they are used to pressing it in opposition to the turn if the slip ball says to. Anyway unless you are holding on an awful lot of aileron during the turn, sufficient for the low % mix to actually move the rudder, you will not get rudder from aileron in the turn.

Welcome to the British weather, don't forget to take your flask of tea to the airfield!

Harry