Evaluation of Trapezoidal Shaped Grooves

Figure 25. Trapezoidal-Shaped Groove Installation on Taxiway Bravo DATA COLLECTION AND RESULTS. The average cutting time, per cutting pass, was the same for both the trapezoidal-shaped grooves and the standard grooves. The entire grooving operation was completed over a 3-day period, due to the limited time that the taxiway could be closed. As with the installation inside the NAPTF, all the equipment, manpower, and supplies used for the airport installation were the same. The speed of installation was identical for both the standard and trapezoidal-shaped grooves at a rate of about 29 ft per minute. Continued analysis of the grooves over the next one year period showed no noticeable disfiguring, collapse, or closure of either of the two groove designs. Researchers attribute this to the fact that the grooves were only trafficked by light commercial aircraft, unlike the heavy loading that was simulated in the NAPTF testing. PHASE THREE SUMMARY. Phase Three results indicate that installation of the trapezoidal- shaped grooves is very similar to the standard groove installation, as it does not require any unique equipment or manpower. Installation of the trapezoidal-shaped grooves was accomplished in the same amount of time, at the same cutting rate as the standard grooves. These findings indicate that the trapezoidal-shaped groove could be installed at an in-service airport without causing any special accommodations or delays. Based on the positive findings of Phase Three, FAA researchers determined that it would be feasible to pursue further testing of the trapezoidal-shaped groove configuration at in-service airports.

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