Av Hazard publicizes safety and operational concerns to help prevent accidents but it works only if we hear from you. Use the postage-free Av Hazard card to describe the hazard and return it to Pro Pilot. To obtain an official FAA review send NASA an ASRS form. For immediate action, call the airport, FBO, ATC, FSDO or the 24-hr FAA Safety Hotline at 800-255-1111. Note: Telephone numbers for all US Towers and ARTCCs are published in Ac-U-Kwik and Pilots Express Airport/Heliport/FBO directories. To report safety concerns outside the US, contact ICAO HQ at 514-954-8219 or via fax at 514-954-6077. ICAO has worldwide telephone and fax numbers to expedite Av Hazard reports to civil aviation authorities.
Localizer excursions at MPV
While flying the ILS for Rwy 17 into MPV (Barre–Montpelier VT), we observed the localizer needle shift left and right—erratically but never more than one dot either side—of course. Our aircraft is equipped with FMS/GPS data, which indicated we were aligned consistently with the final approach course. After landing, we saw a large tractor mowing the grass at the departure end of Rwy 17 near the localizer antenna. We suspect that its movement through this area may have caused the erratic movement of our localizer needle during the approach.
__ ATP. King Air 350
- The tractor mower is the most likely cause of the localizer deflection. AIM Section 1 discusses the vulnerability of glideslope and localizer antennas to interference, which can be caused by surface vehicles or aircraft in the ILS critical areas. When the weather is below 800-ft ceilings and 2-mile visibility, ATC must protect the ILS critical areas by not allowing surface vehicles or aircraft in the critical areas of the glideslope or localizer antennas. Caution is needed at uncontrolled fields as there is no protection. The ILS critical area is marked with a special hold line to keep aircraft clear while taxiing.
With the above-stated weather, the critical area must be protected any time an aircraft is on final approach between the ILS final approach fix and the airport. Landing aircraft should taxi clear of the ILS critical area quickly for aircraft on approach behind. The glideslope has a similar critical area with the same surface vehicle and weather limitations. When weather is above 800-ft ceilings and 2-mile visibility, ATC is not required to provide critical area protection. According to the Av Hazard report the pilot reported the incident to the airport, NASA ARSA and the company—good job! Don’t forget to mention it to ATC while taxiing to the ramp. While they are not required to provide critical area protection if the weather is above 800–2, maybe next time they’ll let you know there is mowing going on near the end of the runway so the next pilot might be on alert for random excursions of the ILS.
Near ground collision at CLT
CLT (Charlotte NC) Tower local controller was on position for 29 min working 9 aircraft with no previous operational errors or deviations. The controller cleared PSA Airlines (JIA) flight 390—a CRJ200—for takeoff on Rwy 18L. A PC12 was waiting to depart Rwy 18L at Intersection Alpha. As required, the ground controller had written on the flight progress strip and coordinated verbally with the local controller that the PC12 was requesting an intersection departure off Rwy 18L at Taxiway A. However, the local controller forgot and instructed the PC12 to taxi into position and hold on Rwy 18L. JIA390 had already begun its departure roll and had traveled approx 1600 ft as the PC12 taxied onto the runway. The ASDE-X alerted. JIA390 began to slow and the controller canceled the takeoff clearance. The PC12 had pulled to the side of the runway when the pilot recognized what was happening. According to FAA, JIA390 stopped approximately 10 ft from the PC12. At the time of the incident the weather was VFR with 9 miles visibility.
- This event appears in an NTSB preliminary report for May 29, 2009 but is included in Av Hazard this month to alert pilots to everyone’s need to monitor the tower frequency for not only your call sign but all traffic concerning the runway you are landing on or taking off from. This incident was classified as an operational error on the part of the ATC controller. However, both flightcrews could have been more alert to operations on Rwy 18L.
The PC12 crew should have been listening on the tower frequency to hear Tower clear the CRJ for takeoff on the runway they were cleared onto. They knew they were departing at Intersection Alpha and an aircraft was cleared for takeoff from the runway they were instructed to taxi on themselves. The CRJ crew did a good job aborting the takeoff and avoiding a collision, but could have paid more attention to knowing what the next aircraft in line behind their aircraft was and note the PC12 was not behind them in line for takeoff but was holding on Rwy 18. We need to encourage the highest levels of situational awareness during critical segments of flight.