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Home My WebLink About14-04 Obstruction Evaluation_AM_AM...a AIRSPACE SAFETY ANALYSIS llwun CORPOP—ror Because you want it right on the first approach OBSTRUCTION EVALUATION FOR Spectrasite Communications ASAC Study Number: SPI 47438-01 Date: December 27, 2001 Search Area ID/Name: CINBWI-0013/Shenandoah Un Search Area Center: Winchester, VA Latitude: 390 09' 12.40" Longitude: 0780 09' 44.90" NAD 83 Surface Elevation: 611' to 779' AMSL Tower Height: 320' AGL Overall Height: 931' to 1099' AMSL This study is conducted in accordance with the Federal Aviation Regulations (FAR) Part 77 and the Federal Communications Commission (FCC) Rules Part 17. This report and the findings, opinions and recommendations expressed herein are intended for the exclusive use of Spectrasite Communications in making appropriate regulatory filings and may not be reproduced by other parties in any form or manner. This study is for a 1 NM radius search area centered at the above coordinates. The overall structure height within the search area varies approximately 931' to 1099' AMSL depending on exact site location. Where overlying airspace usage restricts structure height, maximum no effect structure height will be given in feet AMSL. SPI 47438-01 Page 1 7903 Pehoenix Boulevard, Suite 250, Atlanta, Georgia 33349 678.924.8000 • fax 678.924.8006 • www.asacinc.com MINIMUM EN ROUTE ALTITUDE: No factor. The search area is located below airspace protected for numerous victor airways. However, the proposed 320' AGL structure located in the search area would not adversely affect low altitude en route airways or training routes in the area. VFR ROUTES: No factor. The proposed 320' AGL structure located in the search area would not adversely affect VR routes or VFR routes in the area. AIRPORT IMPACT: The search area center is located 3,543' or 0.58 NM on a True Bearing of 298.88° from the approach end of runway 14 at Winchester Regional Airport, the nearest landing surface for regulatory compliance purposes. The search area center is located 6,261' or 1.03 NM on a True Bearing of 305.260 from the airport reference point (ARP) of this public use, instrumented airport. The search area is located below airspace protected for the VFR traffic pattern at Winchester Regional Airport. At 320' AGL, the proposed structure located in the search area could adversely affect this surface. Additionally, it could affect IFR surfaces at this airport. Private use airports or heliports do not meet FAR 77 criteria and the FAA would not consider them in its study of the proposed structure. However, in the interest of flight safety, ASAC considers private use airports and heliports in every study. ASAC found no evidence of private use airports or heliports, which affect this site. IFR effects will be discussed under section FAR 77.23 of this report. SPI 47438-01 Page 2 FAR 77.13 (a)(1) (Construction over 200' AGL at its site) The proposed 320' AGL structure would exceed this surface by 120'.* FAA Notice of Proposed Construction or Alteration would be required by this section. FAR 77.13 (a)(2)(i) (Structure within 20,000' from the nearest runway of each specified airport with a runway length of more than 3,200') The proposed 320' AGL structure located in the search area would exceed the 100:1 slope at Winchester Regional and fail the FCC slope test.* Exceeding either surface would require FAA Notice of Proposed Construction. FAR 77.13 (a)(2)(ii) (Structure within 10,000' from the nearest runway of each specified airport with a runway length of 3,200' or less) No factor. FAR 77.13 (a)(2)(iii) (Structure within 5,000' from the nearest point of the nearest landing and takeoff area of each specified heliport) No factor. * "Notice of Proposed Construction" is required. SPI 47438-01 Page 3 FAR 77.23 (a)(1) (Structure over 500' AGL) No factor. The proposed 320' AGL structure would not affect this surface. FAR 77.23 (a)(2) (Structure over 200' AGL or above the established airport elevation, whichever is higher, within 3 NM of the established reference point of an airport which has a runway more than 3,200 feet in length. This height increases 100' for each additional mile up to 500' AGL) The proposed 320' AGL structure located in the search area could exceed this surface by 120'. By itself, exceeding this surface would not indicate that the structure would be considered a Hazard to Air Navigation. It would however, trigger an extended study to be conducted by the FAA. This extended study would add approximately 90 days to the FAA's normal processing time. FAR 77.23 (a)(3) (TERPS, Terminal Operations) The search area is located below airspace protected for IFR terminal operations at Winchester Regional Airport (see Enclosure 1). The maximum no hazard structure height due to Category C Circling is 960' AMSL. Additionally, the FAA may request "2C accuracy" survey data for any structure in order to verify exact site location and overall structure height (see Enclosure 2). FAR 77.23 (a)(4) (TERPS, En Route Operations) No factor. The proposed 320' AGL structure located in the search area is clear of all en route obstacle clearance areas and would not increase any minimum obstruction clearance altitude. FAR 77.23 (a)(5) (The takeoff and landing area of an airport or any imaginary surface established under FAR 77) The proposed 320' AGL structure located in the search area exceeds the horizontal surface at Winchester Regional airport by 223'. By itself, exceeding this surface would not indicate that the structure could be considered a Hazard to Air Navigation. It would however, trigger an extended study to be conducted by the FAA. This extended study would add approximately 90 days to the FAA's normal processing time. AM BROADCAST STATION IMPACT - SPI 47438-01 Page 4 FCC rules protect existing AM Broadcast Stations from possible adverse affects caused by emissions from newly constructed cellular radio towers. ASAC found no evidence of AM Broadcast Stations which could impact the search area. The FAA is authorized to protect air navigation and communication facilities from possible interference. The physical presence of a proposed structure and/or the electromagnetic signals emanating therefrom may have a substantial adverse effect on the availability or quality of navigational or communication signals needed for the safe operation of the National Airspace Systems. The Winchester Localizer (TZX) is located within the search area on a True Bearing of ° from the search area center. The FAA may protect this NAVAID from possible electromagnetic interference (EMI) for a distance up to 1 NM. Since the search area is within this protective radius, EMI adverse effect is a possible outcome of an FAA aeronautical study. In ASAC's opinion, the likelihood of an adverse EMI effect finding is moderate. SPI 47438-01 Page 5 I . The search area center is located 3,543' or 0.58 NM on a True Bearing of 298.880 from the approach end of runway 14 at Winchester Regional Airport, the nearest landing surface for regulatory compliance purposes. The search area center is located 6,261' or 1.03 NM on a True Bearing of 305.260 from the airport reference point (ARP) of this public use, instrumented airport. 2. The search area is located below airspace protected for the VFR traffic pattern at Winchester Regional Airport. At 320'AGL, the proposed structure located in the search area could adversely affect this surface. Additionally, it could affect IFR surfaces at this airport. 3. In the interest of flight safety, ASAC considers private use airports in every study. However, private use airports are not a factor for this site. 4. The proposed 320' AGL structure located in the search area would not adversely affect VFR or IFR en route flight operations or procedures in the area. 5. FAA Notice of Proposed Construction or Alteration would be required for the 320' AGL structure located in the search area. 6. The proposed 320' AGL structure located in the search area could exceed FAR 77.23 (a) (2) by 120'. By itself, exceeding this surface would not indicate that the structure would be considered a Hazard to Air Navigation. It would however, trigger an extended study to be conducted by the FAA. This extended study would add approximately 90 days to the FAA's normal processing time. 7. The search area is located below airspace protected for IFR terminal operations at Winchester Regional airport (see Enclosure 1). The maximum no hazard structure height due to Category C Circling is 960' AMSL. Additionally, the FAA may request "2C accuracy" survey data for any structure in order to verify exact site location and overall structure height (see Enclosure 2). 8. The proposed 320' AGL structure located in the search area exceeds the horizontal surface at Winchester Regional Airport by 223'. By itself, exceeding this surface would not indicate that the structure would be considered a Hazard to Air Navigation. It would however, trigger an extended study to be conducted by the FAA. This extended study would add approximately 90 days to the FAA's normal processing time. 9. The Winchester Localizer (TZX) is located within the search area on a True Bearing of ° from the search area center. The FAA may protect this Navaid from possible electromagnetic interference (EMI) for a distance up to 1 NM. Since the search area is within this protective radius, EMI adverse effect is a possible outcome of an FAA aeronautical study. In ASAC's opinion, the likelihood of an adverse EMI effect finding is moderate. SPI 47438-01 Page 6 SPI 47438-01 Page 7 Any structure exceeding 200' AGL would exceed the FAR 77.23 (a) (2) 200' AGL arc and would trigger an extended study. Similarly, any structure exceeding the IFR Horizontal surface would require an extended study. The VFR horizontal surface outlined in light blue is 876' AMSL. The VFR conical surface extends from the VFR horizontal surface towards the northwest, away from Winchester Regional. Its surface begins at 876' AMSL, sloping upward at a 20:1 ratio to 1076' AMSL at its limit outlined in light blue. Any penetration of these surfaces would trigger a Hazard to Air Navigation determination by the FAA. The following options are listed in recommended sequence, with limitations stated. The areas are color -coded on the enclosed chart. AVOID the area on enclosure I that is outlined in red and labeled AVOID. Select a site within the areas outlined in orange on enclosure 1, and propose a structure no taller than 960' AMSL. This area is below the VFR traffic pattern airspace and the IFR category C airspace. Select a site within the areas outlined in yellow on enclosure 1, and propose a structure no taller than 876' AMSL. This area is below the VFR traffic pattern airspace. To find a location for a 320' AGL structure, it is recommended that a location of approximately 3 miles from the airport be studied. With reference to the above recommendations: FAA Notice is required. Marking and lighting may be required. Extended study may be required. Structure is not within AM Broadcast Station interference radius. Structure would not affect flight operations at a private use airport or heliport. Should you have questions regarding this study, its findings, options, or recommendations, please contact ASAC. SPI 47438-01 Page 8 4v� L -_, IJ !Search Area Center f,j,.j!u+.• - 1 -, - - , 1 39° 9' 12.4' 1 ': -78° 9 44.9' �� r r_ NAD 83 •� if' / y .',«' . ir 'DTA• lb' r,... 876' AMSL d di it i.. t'Cdi' L 3r = J t •-{ ,�, �'�lt.y ,r ��Fs' +i}• J� 3' - .jy+ �*(Z[-1 iJ f` 1� l' • GTZX #v�� •- r� �` z aah�ya:, 4 ,��N ✓�' a a.. %i rj v � .�., r ��7,�r rr.yta)ur� sif4. $76AMSL44 i Winch ester,lfA� _ `'. a luT•L. 7.5' Quadrangle r• Ab 611 , a