I Learned About Flying From That: Command Authority

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It was a Cessna 340A model and I was the PIC. A sleek, powerful and very cool looking twin-engine airplane, the 340A is powered by two Continental 310-­horsepower engines. Regarded as a "pilot's airplane," it has good performance characteristics (airspeed and rate of climb) as reflected by a power loading of 10.48 pounds per horsepower, a large useful load of 2,122 pounds, a pressurized ­cabin, and good range of ­approximately 900 nm. I jumped at the opportunity to be in command of this excellent airplane.

It was a hot and humid July afternoon in Florida. I was preparing to take off from Miami/Kendall-Tamiami Executive Airport (TMB) en route to Ocala International-Jim Taylor Field (OCF) with two acquaintances; it was a Part 91 flight. Prior to takeoff, I thoroughly reviewed pertinent weather data, obtained a weather briefing and filed an IFR flight plan. The briefer stated the weather was fairly clear north of the Miami area. There were no frontal systems north of the airport or throughout Florida, only scattered thunderstorm cells along the route. He also stated there was a slow-moving thunderstorm 35 miles off the east coast of Miami and moving westward. He noted if I departed within the hour I would safely miss the thunderstorm. I acknowledged I would be taking off with two ­passengers in about 15 minutes.

With fuel tanks filled, baggage loaded and all aboard, the airplane was within proper weight and center-of-gravity balance limits.

Just prior to boarding, I looked at the weather radar display in the FBO one last time to get the position of the thunderstorm, which was now about 30 miles offshore and slowly moving westward from the Atlantic Ocean. At that distance and with its slow movement, the thunderstorm was not an immediate danger, so I decided it was appropriate to take off. On departure, I assumed I would be given an immediate turn to the north, away from the approaching thunderstorm. I anticipated a successful, safe flight.

Wind direction and speed at the time of departure were 100 degrees and 5 knots. I was cleared to take off on Runway 9R, nearly 6,000 feet in length. On departure, I was assigned to maintain runway heading and to climb and maintain 3,000 feet. After reaching 3,000 feet and just passing the east coast of the state, still heading east as directed by ATC, the sky in front of us got progressively darker, it was raining, and I could see lightning in the distance.

I did not want to fly through a thunderstorm, so I attempted to re-establish radio contact with Miami departure to request an immediate turn to the north. The frequency was jammed with other pilot requests, as well as instructions being issued by ATC. By the tone of his voice, the controller seemed agitated and anxious. I made several additional attempts to contact ATC, but there was no response. The airplane was equipped with onboard weather radar, and it painted an ugly picture ahead. Large, ominous red and yellow colored masses were depicted on the screen. ATC finally acknowledged my calls and I requested the turn to the north. The response was "maintain 090 heading and 3,000 feet altitude." I was now well past the east coast of the state and flying east out to sea. The lightning was getting closer; vertically sheared and horizontally sheared wind gusts caused much turbulence.

Anticipating turbulence, I had already slowed to the airplane's turbulence penetration speed (VB) of 140 kias, as stated in the Pilot's Operating Handbook. VB is not to be confused with maneuvering speed (VA). VB is slower than VA, which was 155 kias (maximum weight). The main difference between VB and VA is that VB is related to force applied to an aircraft by strong, vertically sheared wind gusts striking the wings from below, which instantly increase angle of attack, lift and positive G-loads, as well as gusts from above that instantly decrease angle of attack, leading to negative G-loads, while VA is related to force applied to an airplane by a pilot's full and abrupt movements of the flight controls. I knew it was critically important to maintain VB while flying in the gusty, turbulent conditions and accept changes in altitude to prevent excessive positive and negative G-loads. The Pilot's Operating Handbook states the G-load range for the Cessna 340 is positive 3.66 G's to negative 1.44 G's. Flying within the specified airspeed and G-load envelope boundaries of the V-G diagram minimizes the risks of structural damage and failure to the airplane. I also knew that, by flying at VB, an accelerated stall would occur prior to generating high G-loads. Acting like a "safety valve," the stall precludes the generation of dangerously high loads, preventing airframe damage.

The situation was getting dicey. It was really turbulent and my altitude was changing by as much as 500 feet up and down. By continuing on the eastbound heading toward the thunderstorm, there were potential risks of structural damage to the airframe and a catastrophic inflight breakup. The weather to the north was clear, and once again I contacted ATC and requested an immediate turn to the north. Again, the controller stated "maintain 090 heading and climb and maintain 4,000 feet." He now spoke at a faster cadence and sounded more anxious than me; ironically, I was the one in the airplane — my seat was moving faster than his seat. In front of me at 4,000 feet of altitude and higher were dark, ­cumulonimbus clouds with lightning. I perceived this to be a potential inflight emergency, requiring immediate action.

I made a command decision to contact ATC and state I was declaring a weather emergency, unable to comply with the heading assignment, and turning northbound. This was not a request; after informing ATC of my action I made the turn. The same controller responded, stating "maintain 090 heading and 4,000 feet altitude." He gave no reason for these instructions. I responded by stating "sir, I'm heading northbound at 4,000 feet away from the cumulonimbus clouds and lightning." The controller, objecting to my action, was more anxious than before and seemed angry.

After turning northbound, I looked across the right wing to the black, churning, violent-looking thunderstorm clouds pierced with strobelike pulses of lightning and occasional massive surges of bright white light — tremendous energy. I was relieved to be flying away from this menacing meteorological monster and potential destroyer of aircraft and human lives. Prior to being handed off to the next controller, the anxious Miami controller reluctantly cleared me to a heading of 350 and stated that, upon arrival in OCF, I was to call Jacksonville Approach Control on the telephone about the incident. I acknowledged the transmission and thought that my decision to turn was appropriate. I contacted the next controller and was cleared direct to the Lakeland vortac and eventually cleared to OCF. The weather was fairly clear for the remainder of the flight, and I proceeded without further incident.

After landing, I made the telephone call to Jacksonville Approach Control and explained the incident in much detail to a supervisor. Additionally, I cited FAR 91.3, Responsibility and Authority of the Pilot in Command, as justification for my action for not complying with ATC and turning northbound. Essentially, it states the PIC is the final authority as to the operation of an aircraft and, if there is an emergency requiring immediate action, the PIC may deviate from ATC's instructions. The supervisor accepted my explanation. Following this incident, which happened many years ago, I was never asked to submit a written report.

What did I learn from this flight? Over the years I've thought about my decision to take off that day. As for every takeoff, all interacting weather conditions need to be considered. While flying, we're taught to give thunderstorms a wide berth and fly around them by at least 20 miles so as not to be adversely affected by hazards like hail, lightning and potentially destructive turbulence. In this situation, at the time of departure the thunderstorm was localized 30 miles east of the airport; it was slow-moving; there was no thunderstorm activity north, south or west of the airport; and surface winds were light. Given all these conditions, and with ATC's cooperation (a turn to the north), I decided to take off. In addition, the weather briefer reinforced my thinking by stating I would be safe if I departed within the hour. Alternatively, a weather delay of four to six hours, allowing the thunderstorm to move well past the airport to the west, would have been a safer decision, which, admittedly, I would do today.

I also relearned we all make mistakes — we're all human. The air traffic controller's perspective in this incident should be considered. It was a weekday afternoon with much traffic activity. He was very busy stating instructions to multiple flights, issuing complex clearances as well as coordinating the flow and separation of traffic. To compound matters, there was the potential danger of an approaching thunderstorm, albeit the thunderstorm was far away from the airport at the time of my departure. From his demeanor on the radio, I can understand his anxiety. In viewing my aircraft on the radar screen, he may have thought I was not in immediate danger and could maintain heading. He gave no reason for me to maintain the easterly heading. Perhaps he was distracted by other priorities and forgot to monitor my position vis-à-vis the approaching thunderstorm. Or, could it be the controller dimmed out the weather on his radar screen to better see all the traffic and lost situational awareness of the thunderstorm? Considering all of the above, it remains unclear why the air traffic controller mistakenly vectored me toward the thunderstorm.

Although I was not asked to submit a written report, I learned I should have visited NASA's Aviation Safety Reporting System (asrs.arc.nasa.gov) to complete a report of the incident (NASA Form 277) by describing the reasons for my heading deviation. Doing this helps the air traffic control system understand the reasons for aviation-related incidents. Also, had the FAA examined this incident, the report may have served as a "get out of jail free" card for me. Subsequently, and when appropriate, I have completed such reports to NASA's Aviation Safety Reporting System.

This story is not meant to impugn air traffic controllers. On the contrary, these dedicated individuals provide traffic separation, coordinate flights and issue safety alerts to pilots headed for trouble. Their contributions to flight safety are invaluable and appreciated. Generally, their instructions are appropriate; however, there may be occasions when inappropriate instructions are issued, predisposing to an unsafe situation.

Labeling air traffic controllers as "controllers" may convey to some pilots that an air traffic controller, not the PIC, is in control of the flight. In the Federal Aviation Regulations, Part 1, Definitions and Abbreviations section, PIC is defined as the person who has final authority and responsibility for the operation and safety of the flight. There is one person in command and control of a ship at sea: the captain. Similarly, there is one person in command and control of an aircraft in flight in all situations: the PIC.

The PIC should never allow his aircraft to be placed in a risky, unsafe situation. In situations similar to this incident, the PIC should exercise ­command authority by refusing inappropriate/unsafe instructions and requesting something safer. A pilot should never allow his command authority to be abrogated by another person on the ground and not in harm's way.

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