Atos Mods

The following 5 pictures are from Jim Yocum.  The first three are of the T-tail made by John Vernon.  In this picture there is a small string visible between the two horizontal surfaces.  This is the limiter string that prevents the tail from rotating more than 90 degrees.

The T-tail is free to float above the horizontal axis in flight.  This enables it to produce very little drag in flight.  If the nose of the glider suddenly pitches down. the tail will hit the horizontal stop and add down force to the glider to help prevent pitch over (tumble).

The vertical riser of the T-tail help keep it out of the weed/crops, launch carts, etc.

This is the V-tail made by Felix at AIR.  This tail is fixed in place.  It is designed so the angle is such that there is minimal drag in flight.  When the nose pitches down the tail provides down force to help keep the glider from pitching over (tumble).

Since the tail is fixed, it also dampens any pitch up as well.  Pilots who have flown with this tail have reported the bar movement is more dampened in pitch.

These next three pictures show a slight modification I had to do to prevent the flaps from hitting the Wills Wing Slipstream down tubes. Click on the link for Wills and then enter Atos under the search and it will come up with the part number and price for the control frame.

The down tubes are part of a complete control frame package from Wills Wings that includes carbon basetube and new front and rear wire sets.

The flaps not deployed in this picture.

The red arrow in this picture is pointed at the spoiler limiter rope.  Some early C models and Stratos C models were shipped with the limiter rope in the center.  The limiter rope should be moved to the #6 rib as in previous versions of the Atos.

Some pilots place extra padding between the D-cells near the spoilers to prevent the D-cells from bumping together in transport.

An aeronautical engineer suggested that placing shear ribs on the Atos would help dampen the pitch when encountering gust loads.  I used Velcro  sewn between two pieces of self adhesive Dacron sail cloth.  I did not notice any difference in flight and I removed all of them.

The shear ribs are visible at each rib.

This shows how I modified my base tube to provide extra support around the flap cleat.  On early model C's, they notched the base tube for the cleat.  On the new base tube the cleat is covered as in my picture.  They do a much better job and the new base tube is all caron as are the uprights.  Having the cleat covered is also easier on my right hand. 

I like to carry my harness bag in my sail.  To prevent it from sliding forward and jamming the spoiler cables, I installed two shear ribs, one on each side of the keel.  They are about 8" back from the pulleys. 

This is my modified spoiler.  It is about the same size and shape as the original Atos spoiler.  The glider turns much faster with the new spoiler, but only when given maximum deflection.