Northwest Mountain Region
Salt Lake City Center
“Northwest 1273 thank you. Radar services terminated. You can contact Bozeman Tower at 118.2.”
“Ok, over to the tower at 118.2. Goodnight, Northwest 1273.”
With that very simple communication, Salt Lake Center air traffic controller Lee Wheeler transferred the radar services of Northwest 1273, an Airbus 320 inbound to Bozeman, Mt., from Minneapolis, to the tower at the Bozeman Airport (BZN) for landing.
Wheeler was also working a SkyWest jet into Bozeman and both aircraft had been holding for approximately 30 minutes due to weather. Once the weather cleared, Wheeler issued the approach clearance to NWA1273 and transferred radar services to the Bozeman tower.
Approaches into BZN are typically non-radar, due to the high terrain in the area that blocks the radar from picking up the aircraft’s signal. Without a signal, controllers are blind to the aircraft’s location. This was the case on February 19, 2007, as Wheeler did not have visual radar contact with NWA1273.
As the pilot of SKW4058 was waiting for his approach clearance into BZN, he indicated the weather had improved and he would be able to do a visual approach. However, without radar contact with NWA1273, Wheeler could not send SKW4058 into BZN, until he had verification from the tower at BZN as to NWA1273’s location.
Wheeler contacted Bozeman Tower, asking for the location of NWA1273. The BZN controller responded that he had the SkyWest in sight but not the Northwest.
At that point, Wheeler received a freak hit on his radar, indicating NWA1273 was really far off course. Wheeler then radioed BZN again stating, “I think that Northwest is confused on the approach. He is 35.5 miles northwest of the airport.”
Wheeler then asked the BZN controller to contact NWA1273, upon which the pilot responded by telling the controller to “standby one second.”
Upon hearing this, Wheeler immediately cancelled the approach clearance for NWA1273 and told the tower controller to tell the pilot to climb and maintain 11,000 feet immediately for terrain and that he had a low altitude alert.
Wheeler also reported the same message himself on the guard radio frequency in case the pilot was monitoring that frequency.
The BZN controller was successful in contacting the pilot and put the pilot back onto Wheeler’s frequency. Wheeler responded, “NW1273, Salt Lake Center has you radar contact. Low altitude alert. Climb and maintain 11,000 immediately. The terrain in your area is 10,800.”
Once the pilot reached 11,000 feet, Wheeler questioned the pilot as to what happened. “NWA1273, I don’t know where we messed up there sir, but you’re 36 miles from the airport, well beyond the parameters of the published profile on the approach.”
All the pilot said in response was “NW1273, Roger.”
The pilot had found a very dangerous place. But Wheeler’s actions that night prevented a possible major accident involving a passenger jet. His persistence and attention to detail enabled him to locate the aircraft and make sure the aircraft remained at a safe altitude until he was safely on the ground in Bozeman.
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