Wing Tip Skids and Wheels
General Comments
One of the issues in the Standard Cirrus design is the emphasis on performance over practicality.
This is the case with wing tip protection. The factory device is a very small stainless steel skid that is
rugged and aerodynamically efficient. But it allows the wing tip to nearly touch a flat surface and permits
aileron corners to scrub the pavement. A little camber or unevenness in the surface and the outer wing
has no protection at all. This is not a shortcoming in the eyes of someone intent on squeezing
the last bit of performance from a ship, but now that the Standard Cirrus has been ecclipsed by 30 years of
performance improvements, owners are more likely to be concerned with preservation than performance.
One obvious idea is to simply install the tear drop, flexible composite wing tip skids used on newer Schempp-Hirth gliders.
You can even keep the original stainless steel skids as insurance in case you loose one of the tear drop skids.
Following are other suggestions:
Tomás Díaz' Wing Tip Wheels
Tomás Díaz provided the following images of his solution. He states:
How many times as Standard Cirrus sailplane owners we must work in winter on the bottom of our wings,
to fix damage from landings or take offs when the wings touche the ground, as in fields with little stones or hard runways.
I solved this. A rubber skid in the extreme of the wing is not enough. These can be to replaced by wheels
manufactured by HPH.Ltd. In the US, you can get them from
Wings & Wheels, an HPH.Ltd dealser.
My friend has an ASW 24 with the same problem. We both installed these wheels two years ago. The result is Wonderful.
In the photos below you can see, the wheel supports are glued to the wing. We use polyurethane putty.
It’s very easy to do, and if necessary, can be removed very easily, leaving a clean wing surface.
Another good point is that you can remove the wheel with only one central screw.
In Spain, my Standard Cirrus was the first with these wheels. Now, five have them.
The wheel supports need only a few hours of reshaping to match the wing profile. Three hours in my case.
Some people like to attach them with silicone cement, but I think polyurethane putty is much better.
The result looks very nice and reduces wing root loads when landing.
It also is very good for ground handling.
(Tomás is from Spain. I have taken some liberties in editing his English. Jim Hendrix)
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