John W. Low filed two patents on May 29 1979, one for a Hooded Kite which is another version of a Sled type kite that incorporates a hood, the other took a completely different approach.
With all pervious designs with the exception of the Hornbeam, Sled kites had straight leading edges and trailing edges.
Most of the Sled kite designs had a problem of been sensitive to collapse in turbulent wind.
John W. Low claims to have overcome these limitations to the Flexible Kite design by making several important modifications to the basic design of the Sled type kite. The central panel has been altered from a rectangle, to one which is the shape of a swallowtail.
To archive the required shape, three longitudinal stiffening battens are used.
The central batten is moved forward by about 20% of the two side battens to form a triangle leading edge.
If the wind condition changes and causes the kite to collapse the triangle leading edge catches the wind and reopens the canopy.
The trailing edge is cut away to form a isosceles triangle, the height of the triangle is greater than that of the leading edge.
The trailing edge shape provides the wind inside the canopy to spill from the kite before completely leaving the kite, providing additional stability.
The design of the trailing edge also uses a cord tension across the two outboard battens, this holds the canopy at that point to form a trough.
Even with the slightest wind, the held shape provides a strong reaction at low wind velocity.
The design requires a long bridle as do all other flexible Sled type kite.
Patent issued to John W. Loy, July 21 1981
U.S. Patent 4,279,394