The Controller Failed to Inform...

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Back before the days of Nexrad on a GPS screen, controllers were usually the only resource for pilots of light airplanes without weather radar to avoid bad weather. Even though their screens were not optimized for showing weather, they could usually steer a pilot around the worst areas. Controllers have also been very helpful in pointing out conflicting traffic. Most of the time the traffic has been "no factor," but every once in a while I am very glad I got the alert from the controller.

The problem with all this wonderful help from controllers is that we can begin to rely on them too much. We can figure that as long as the controller has us on his screen, we don't need to watch for traffic as much, or we don't have to worry about the weather ahead, or it doesn't matter if we are not aware of restricted airspace up ahead. Murphy's Law states that just when we need the controller's help the most is when the controller will let us down. The problem is that we never know when the controller is not paying attention to us at that moment, or has decided that it is none of his business if we fly into a mountain or thunderstorm.

The accident in April 2006 that claimed the life of test pilot Scott Crossfield provides a chilling example of this. Crossfield had carefully checked the weather numerous times before departing Prattville, Alabama, en route to Manassas, Virginia. He knew thunderstorms were forecast, and mentioned to an acquaintance that he "might need to work his way around some weather, but it did not look serious." The only weather avoidance equipment in the 1960 Cessna 210 Crossfield was flying was a Stormscope.

As he was proceeding en route at 11,000 feet, a squall line of Level 5 to 6 (intense to extreme) echoes consistent with heavy precipitation supercell thunderstorms developed across his intended path. The controller Crossfield was talking to was aware of the storms, he knew other aircraft were avoiding the area, and he was only working one other airplane at the time, yet he never called Crossfield to warn him of the dangerous weather ahead. The NTSB reports he stated this was because "he felt that weather conditions displayed on his radarscope were unreliable," and that "pilots have a better idea of where adverse weather is and he expects them to inform him on what actions they need to take to avoid it."

Another striking example was covered in last month's Aftermath column by Peter Garrison. In October 2004 an air ambulance Learjet 35 departed Albuquerque at 3:15 p.m. with two pilots and two medical crewmembers. After a short leg to pick up an additional medical crewmember in El Paso, they flew to Manzanillo, Mexico, where they picked up the medical patient and one accompanying passenger. They departed Manzanillo at 8:40 p.m. and arrived at Brown Field Municipal Airport in San Diego, California, around 11:30 p.m., where they dropped off the patient and passenger.

As the crew prepared to depart for their home base, there were many indications of the fatigue they must have been experiencing after being awake for almost 18 hours and working an 11-hour duty day. Just after midnight, a crewmember filed an IFR flight plan back to Albuquerque with the San Diego Flight Service Station, but did not request any weather, the clearance or a clearance void time. As the crew prepared to depart, the cockpit voice recorder showed that the captain and copilot listened to the remarks portion of the ATIS, but did not listen to the weather information.

The NTSB report states that the copilot then attempted to contact "Brown Field Municipal Clearance," obviously unaware that the tower had been closed since 10 p.m. When he received no response, he attempted to contact Tijuana tower, located about five miles away, and San Diego FSS with no success. Finally the captain said, "All right, let's just do VFR," meaning that they would depart VFR and then pick up the IFR clearance in the air. They apparently did not consider using their cell phones or the satellite phone the airplane was equipped with to call FSS and get the clearance before they departed.

The crew decided to depart to the east on Runway 8 to avoid San Diego and the Class B airspace to the north and west of Brown Field. The problem is that to the east, the terrain rises over 3,000 feet within seven miles. With the last minute change to a VFR departure, there is no evidence the crew checked the terrain or consulted the instrument departure procedure, which requires a climbing left turn to 280 degrees to avoid the mountains to the east.

Once airborne, they contacted the Southern California Terminal Radar Approach Control controller, who gave them a transponder code and asked them to ident. He then told them to turn to a heading of 020 degrees, maintain VFR, and expect an IFR clearance above 5,000 feet msl. At that point the airplane was only 3.5 nm west of the mountains, and the NTSB report points out that "the heading issued by the controller resulted in a flight track that continued toward the mountains." A review of the controller's display data recording revealed that the controller's computer system issued both an aural and visual minimum safe altitude warning a few seconds later.

The airplane crashed less than a minute later at an elevation of 2,256 feet msl, which is about 100 feet below the broken to overcast layer of clouds that covered the area at that time. (The accident site was only 1.5 miles from a similar corporate jet crash that occurred about 14 years earlier.) As the NTSB report points out, the crew made numerous mistakes that night, which it attributed to fatigue. These included not familiarizing themselves with the terrain, trying to fly visually at night in an area with few or no lights on the ground, and not checking and using the instrument departure procedure.

The big question was, why didn't the controller warn them of the rising terrain, and why did he give them a heading that would in fact take them directly towards the highest terrain? It is not as if he was not familiar with the area. The controller had previously worked in the Brown Field control tower. Other traffic was not a factor, as the accident airplane was the only traffic the controller was working at that time of the night.

The NTSB reports that the controller stated "he issued the 020 degree heading to keep the flight away from Mexico's airspace, which … was his first priority, … and to turn the airplane toward the first waypoint, which … was his second priority." When asked why he didn't warn the crew about the higher terrain, the controller stated, "it was the pilot's responsibility to avoid terrain when operating under VFR," and that "he did not distinguish between day or night operations when providing VFR advisories to pilots." He also stated "he was aware of the cloud ceiling of 2,100 feet agl and that he expected the pilots to maintain VFR and to advise him if they were unable to do so."

The controller said he did not hear or observe the low altitude alerts because he was on the landline pointing out the flight to the Tijuana approach controller. However, the alerts began 34 seconds before he initiated the call, and radar contact had actually been lost for 15 seconds when he began the call. The NTSB felt "these data suggest the controller may have been aware of the alerts but disregarded them because of his belief that it was not his responsibility to provide alerts to flight crews operating under VFR."

The NTSB also pointed out that once he gave the crew a heading, "the responsibility for terrain clearance is transferred to the FAA," and that in any case, "the primary purposes of ATC … are to prevent a collision and to remain vigilant for situations that warrant the issuance of alerts to flight crews regarding hazardous proximity to terrain, obstacles and other aircraft." Fatigue may have been a factor, as the controller had also been awake for at least 18 hours. In fact, he had worked from 6:30 a.m. to 2:30 p.m. the previous day, and had started his second shift at 11 p.m. with no sleep since the previous shift.

You never know what kind of controller you are talking to. By and large controllers are dedicated people. They really care about their jobs and want to do whatever they can to help keep pilots safe. But controllers are also human. Controllers range from the extremely dedicated to those who might not care quite so much to possibly a few who just don't give a damn. Even the best controllers have bad days, when they are tired or distracted. Some controllers may have had bad experiences with pilots that poisoned their attitude.

My philosophy is that it never hurts to have someone else keeping an eye on you, so I personally use flight following whenever possible. However, I never use the fact that a controller has me on his scope to relax my guard or abrogate my responsibility to plan carefully, to be ready for all possible contingencies, and to be alert and ready to deal with any new risk factors.