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Setting up Ailerons S1-S

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tl_z_bub

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I've been measuring the aileron deflections on my S1-S. Suffice to say that they are all over the place compared to the "stock" deflections :(

In summary

Left upper wing / Up = 8.9 deg, down = 17.8 deg
Left lower wing / Up = 9.7 deg, down = 17.8 deg

Right upper wing / Up = 13.3 deg, down = 19.4 deg
Right lower wing / Up = 12.8 deg, down = 18.4 deg


This particular aircraft is built with all "factory" parts, so I'm assuming that my particular problems stem from incorrect setup. I'm well aware of the potential problems with rose joints in the torque tube / elevator circuit (which I will sacrifice some aileron deflection for if needed), but I'd very much like to improve the current situation if at all possible.

I don't think that the limiting factor on my aircraft is the ability of the individual ailerons to deflect the required amount (down 23 deg, up 25 deg according to the UK "TADS"), but I do predict that the slave strut movement near the lower wing trailing edge and the elevator rose joints could be a problem.

My plan as it stands is to

1) Remove the slave struts (top to bottom wing)
2) Disconnect the aileron pushrods at the outer bellcranks and establish the max deflection possible of the bottom ailerons each side (note angles bottom wing)
3) Reconnect slave struts and repeat (note angles top wing)

If the above is > 25 deg then OK, if not I'll do what I can to improve as much as possible

4) Undo all rose joint locknuts in the aileron pushrods between torque tube and outer bellcranks. Adjust lengths to get idlers and bellcranks at identical and correct angles with stick central
5) Identify what limits max travel (Stick / rose joints / idlers & cranks ?). Quantify what max travel is possible within these constraints
6) Reconnect outer bellcranks and re measure deflections

If the above is >= the max in the first section deg then OK, if not I'll do what I can to improve as much as possible this time focusing on the limitations identified in 4 to 5

I'm kind of hoping that someone out there can offer advice on

- What sorts of angular rotations / pushrod movements are needed at what points in order to achieve the 23 /25 deflections ?

- Any tips / tricks to getting the rose joints safely optimised in the torque tube / elevators for max aileron deflection ?.

- Is the above approach sensible .... or is there a better way :confused:.

- The aircraft seems to fly fine ..... am I just wasting my time !!
 
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