Dear Councilman Gipson,
Your first important vote on the airport is rapidly coming to you as quickly as staff can place it on council’s next earliest agenda. GTAB at its June 12th meeting voted to approve staff’s recommendation for its non-prior announced agenda Item “I”. That recommendation is for city council to approve a pre-drafted letter from the city manager to TxDOT AVN for a $3.1 Million 90% federal grant to upgrade RW 18/36 to support 60,000 pound single-wheel loading. Such runway strengthening would accommodate larger, heavier, and noisier aircraft than can currently operate off that runway. According to the GRW-Willis 2005 Master Plan, RW 18/36 currently can accommodate up to 30,000 pound single-wheel loadings.
It is my understanding from the said master plan that the critical aircraft family for an airport determines the AIRPORT REFERENCE CODE (ARC), the classification system used to relate aircraft approach speeds and wingspan to airport design criteria. The ARC has two components: the first is a letter depicting the aircraft’s approach category and relates to the aircraft’s approach speed. The second depicted by a roman numeral is the airplane design group and related to airplane wingspan (physical characteristics). These are demonstrated by the following examples:
Category B: Aircraft approach speed 94 knots or more but less than 121 knots.
Category C: Aircraft approach speed 121 knots or more but less than 141 knots
Group II: Wingspan of 49 feet up to but not including 70 feet.
Currently, RW 18/36 is designated to accommodate C-II aircraft. RW 11/29 is designated to accommodate B-II aircraft.
Currently, per GRW-Willis, the pavement of RW 18/36 is capable of supporting 30,000 pound single-wheel loadings, which is in the low end of pavement strength required to accommodate jets in ARC C-II category. Pavement strength for RW 11/29 is 12,500 single-wheel loadings. RW 11/29 is restricted from accommodating any aircraft weighing 12,500 pounds or more.
GRW-Willis recommended in its master plan that RW 18/36 be upgraded to 60,000 pounds dual-wheel loads as this improvement would allow accommodation of almost the full range of jets in the ARC C-II category and upgrade RW 11/29 to 30,000 pounds single –wheel loads to share in some of the high noise aircraft operations.
GTAB at its June meeting approved staff’s recommendation to council for its approval of a letter from the city manager to TxDOT AVN requesting a $3.1 Million 90% federal grant to upgrade RW 18/36 to60,000 pounds single-wheel loads.
There is no question that such a modification would allow bigger, heavier and noisier aircraft to operate on a regular day and night basis from our airport than currently authorized. However, questions remain as to what extent does this expansion in operations service represent as to the size, weight and noise of such new aircraft compared to those we now experience. The Airport Manager never addressed that issue to the GTAB and no GTAB members requested the information.
Clearly, clarity of new type aircraft that would be accommodated by construction implementation of the GTAB recommendation and the issue of their adverse impacts on residents of District 5 and the entire community requires full and complete vetting for the entire community. There is also the issue of necessity of a new Part 150 Noise Compatibility Study due to these new proposed operational aircraft. This proposed item for city council agenda should be sent back to the GTAB for such full vetting in a free and open workshop in which the general public can freely participate.
I and a small group of ACC members would appreciate an opportunity to meet with you for a discussion of this issue.
Respectfully,
Hugh (Carl) Norris
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