If the minimum gap between the deflected flap and the fuselage exceeds 5 per cent of the wing semi-span, interference will be negligible.

Aircraft models with up to 7 m wing span, or half-models of 5 m semi-span, can be mounted on the underfloor external six-component balance.

The engines were mounted in nacelles underslung from the upper wing, There were two fins, each placed at the mid semi-span of the tailplane.

Firstly, the coordinate for the spanwise location is transformed by , where y is spanwise location, and s is the semi-span of the wing.

(Airplanes with strut-braced wings achieve substantial wing bending relief by having the load of the fuselage applied by the strut mid-way along the wing semi-span.

The most successful NASA experimental results were obtained on a quite low 6:1 aspect ratio wing (Grumman Yankee AA-1), with a DLE placed at 57% of the semi-span.

Both the late Don Dunford and Tom Pratt have used delta shapes, Don with a smaller 'pilot' delta about 30 metres above the main litter, and Tom with a stack of up to four deltas closely stacked barely a semi-span apart.