The model shown in the two photographs was designed for the vertical water tunnel at "DERA BEDFORD".

It was a model reviewing the use of air blown through the leading edges to create, :-
"AIR-JET VORTEX
GENERATORS".

The model consisted of three interchangeable leading edges, all with various sized and angled .5mm holes.

The aerofoil also has a small flap connected to the trailing edge and although this was not a difficult component to manufacture it was certainly difficult to actuate.

We overcame the problem by inserting a fitted tube to the main body and setting into this a second tube that was connected to the flap actuation arm.

To ensure we were still maintaining a water tight fitting, we built rubber "O" rings into the body, thus achieving all requirements.

The model although by no means one of our most difficult ones, was one that created problems that we did not anticipate when first reviewing it.
Discussions with the engineers who had experience with the use of the tunnel it was tested in, enabled us to produce a model to the required specification, and one that was simple and reliable in its testing.