Screwless Cowl

The Velocity plans call for the cowling to be attached via countersunk machine screws captured with nut plates. This installation technique works well and has been used on the majority of flying Velocities.

There are a number of real advantages and a few features that appeal to our vanity:

The cowl can be removed by pulling six pins; very simple and quick. There are no screws to come loose and go through the prop. The height challenged owner does not need a step to get to the screws on the top of the cowl. It is aesthetically pleasing to the eye. It adds that “how the heck did he did do that?” factor for the casual observer.

How it is done:

The existing cowl pieces have a flange on the forward face. This is the flange that hold the nut plates for the standard attachment.

The flange is trimmed back to 1/2" to 5/8”.

 The inside surface of the flange is covered with duct tape.

 A three bid layup, three inches wide, is laid from the firewall onto the duct tape.

Cowl slot lay-up on upper cowl.

Trim the new lay-ups. This forms the slots that capture the cowl flanges.

Lower cowl slot is trimmed flush.

Upper cowl slot is left long.

 The sides of the cowl are attached with three hinge pieces on each side.  Top of wing, bottom of wing and cowl-to-cowl aft of wing.

I used machined aircraft. If I did it again, I would use hardware store grade rolled hinge. The aircraft hinge is expensive and will not loosen over time. The hinge sections are many times stronger than the original screws so are overkill as a fastemer.

Upon initial installation, the hinges will be tight; and it will make installation and removal a little more difficult. In this case a "sloppier" fastener woulld work better. The hardware hinge will "break in" over time, the aircraft version probably won't.