A Floating Airfield

By

Major General Norris B. Harbold

"The following is an account of one of the problems encountered during the building of the airfield. Some of the names have been forgotten, but this as my recollection of it..."

In May of 1942, work began on the construction of two concrete runways and their taxiways. This took place at the site of the single paved runway used by Delta Crop Dusting Company, which the Army Air Corps had taken over.

The two runways were designed by the U. S. Corps of Engineers and became a standout for Air Corps Training bases. The plan was devised and specifications were adjusted to fit local soil, type and weight of the aircraft, and prevailing winds. The layout and grading began.

Soil compaction was required before the concrete could be laid at the proper reinforcement and thickness. The big rollers with their compacting pads became part of the operation.

It was soon discovered that these big rollers did not cause compacting of the soil. Instead, the unaccustomed weight and agitation siphoned up the water which lay but a few feet under the surface.

Time was a key factor in the completion of the runways. At this point in the construction, there was no time to move the location the location of important runways. This was a monumental problem presented to the engineer.

The only possible solution was to float the runways. This was accomplished by grading the runways to the level required for the concrete slab. The thickness of this slab had been increased by several inches over the original specification. Once the runways were graded, they were allowed to crust and the agitated water was allowed to resettle at its original level.

The concrete was poured at the new thickness and profile. Tests proved that the new profile of amended specifications was adequate. The construction continued.

The runways at Selman Field still float on a field in Ouachita Parish. The soil there remains dry only because of a slant levee, an elaborate drainage system, and a permissive river.