Investigation of Drill Testing For Pancake Lights

The installation of "Pancake" or inset lights with low profile characteristics, in runways or taxiways, will require that practical methods for installation be developed prior to their consideration for full-scale implementation. This report provides the results of operational testing of a number of drills and drill rigs which was performed in order to determine the most satisfactory equipment available for producing the recesses required for the installation of an inset type light.

The drills and drill rigs tested for this report were used primarily for installation of inset lights in the first 3000 feet of Runway 13. This section of Runway 13 consists of 2000 feet of concrete pavement constructed 2 1/2 years ago, in which an aggregate of medium hardness was used and 1000 feet of concrete pavement constructed 20 years ago and containing a very hard aggregate.

From the results of this investigation, it is recommended that:

1.Segmented core drills be used for cutting recesses for inset lighting fixture installations.

2. Development of drills be continued since the segmented core drill requires considerable hand labor to remove the material in the kerfed area.

Recommendations are also included concerning the features of a drill rig which should be employed in order to prepare recesses with a minimum of time and effort.