My Unsatisfactory Condition Report (UCR-330069) was submitted on September 26,1988. The UCR was closed on April 4, 1989. The official reply I received follows...
(original on file)
ITEM 11b.
This UCR clearly indicates that extensive research was conducted by the submitter (sic). We do not, however, agree with Mr. Lusch's conclusion that what he describes is an unsatisfactory condition or compromise.
This UCR raises two primary issues: 1) The process of Selective Rejection that is used to determine the radar data that is presented on a display from existing radar sites and 2) The fact that additional sites are not integrated into our display system.
We believe that the methods used to filter and display radar data are sound, including the selective rejection process. Radar sort box adaptation is established as the result of evolution through use and modification of the data base, i.e. the radar site adapted to a given sort box is the one that provides the best coverage. If a defienciency (sic) is identified that can be corrected by assigning a different site, it is done.
We have looked into alternatives including "double preferred" adaptation and patch IT-200-CPF-008. Both of these methods have significant disadvantages or problems such as the possibility of extensive clutter or loss of adequate display production depending on atmosphere conditions. In short, the limitations do not out weigh the potential advantages, and implementation would not provide an overall improvement.
We do have plans to add several additional radar sites to our system when the capability to expand becomes available with the PAM replacement installation. Additional sites, particularly in the south eastern portion of our control area will expand coverage approximately 2,000 feet lower than existing, but coverage will still be well above ground level. The main advantages of more radar sites will be the redundancy provided by overlapping coverage.
The orginator (sic) has described some limitations of our system but not unsatisfactory conditions. Non radar procedures are satisfactorily applied in certain portions of our area to accommodate IFR users. Because we can and do respond to site coverage concerns through adaptation changes, we provide the best overall radar data display available; we've been able to either provide coverage or clearly identify areas where radar is not available and prescribe alternate procedures.
Although we consider this UCR closed, we would recommend that Mr. Lusch's proposal and research be forwarded to the FAA's Technical Development Personnel for analysis and use, with full credit and recognition of his efforts.
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