Monday Accidents & Lessons Learned: Airplane Mode
When you hear the words “mode” and “aviation,” many of us who are frequent flyers may quickly intuit the discussion is heading toward the digital disconnection of our cellular voice and data connection in a device, or airplane mode. Webster defines “mode” as “a particular functioning arrangement or condition,” and an aircraft’s system’s operating mode is characterized by a particular list of active functions for a named condition, or “mode.” Multiple modes of operation are employed by most aircraft systems—each with distinct functions—to accommodate the broad range of needs that exist in the current operating environment.
With ever-increasing aviation mode complexities, pilots must be thoroughly familiar with scores of operating modes and functions. No matter which aircraft system is being operated, when a pilot is operating automation that controls an aircraft, the mode awareness, mode selection, and mode expectation are all capable of presenting hazards that require know-how and management. Sure, these hazards may be obvious, but they are also often complex and difficult to grasp.
NASA’s Aviation Safety Reporting System (ASRS) receives reports that suggest pilots are uninformed or unaware of a current operating mode, or what functions are available in a specific mode. At this juncture, the pilots experience the “What is it doing now?” syndrome. Often, the aircraft is transitioning to, or in, a mode the pilot didn’t select. Further, the pilot may not recognize that a transition has occurred. The aircraft then does something autonomously and unanticipated by the pilot, typically causing confusion and increasing the potential for hazard.
The following report gives us insight into the problems involving aircraft automation that pilots experience with mode awareness, mode selection, and mode expectation.
“On departure, an Air Carrier Captain selected the required navigation mode, but it did not engage. He immediately attempted to correct the condition and subsequently experienced how fast a situation can deteriorate when navigating in the wrong mode.
“I was the Captain of the flight from Ronald Reagan Washington National Airport (DCA). During our departure briefing at the gate, we specifically noted that the winds were 170 at 6, and traffic was departing Runway 1. Although the winds favored Runway 19, we acknowledged that they were within our limits for a tailwind takeoff on Runway 1. We also noted that windshear advisories were in effect, and we followed required procedure using a no–flex, maximum thrust takeoff. We also briefed the special single engine procedure and the location of [prohibited airspace] P-56. Given the visual [meteorological] conditions of 10 miles visibility, few clouds at 2,000 feet, and scattered clouds at 16,000 feet, our method of compliance was visual reference, and we briefed, “to stay over the river, and at no time cross east of the river.
“Taxi out was normal, and we were issued a takeoff clearance [that included the JDUBB One Departure] from Runway 1. At 400 feet AGL, the FO was the Pilot Flying and incorrectly called for HEADING MODE. I was the Pilot Monitoring and responded correctly with “NAV MODE” and selected NAV MODE on the Flight Control Panel. The two lights adjacent to the NAV MODE button illuminated. I referenced my PFD and noticed that the airplane was still in HEADING MODE and that NAV MODE was not armed. Our ground speed was higher than normal due to the tailwind, and we were rapidly approaching the departure course. Again, I reached up and selected NAV MODE, with the same result. I referenced our location on the Multi-Function Display (MFD), and we were exactly over the intended departure course; however, we were still following the flight director incorrectly on runway heading. I said, “Turn left,” and shouted, “IMMEDIATELY!” The FO banked into a left turn. I observed the river from the Captain’s side window, and we were directly over the river and clear of P-56. I spun the heading bug directly to the first fix, ADAXE, and we proceeded toward ADAXE.
“Upon reaching ADAXE, we incorrectly overflew it, and I insisted the FO turn right to rejoin the departure. He turned right, and I said, “You have to follow the white needle,” specifically referencing our FMS/GPS navigation. He responded, “I don’t have a white needle.” He then reached down and turned the Navigation Selector Knob to FMS 2, which gave him proper FMS/GPS navigation. We were able to engage the autopilot at this point and complete the remainder of the JDUBB One Departure. I missed the hand–off to Departure Control, and Tower asked me again to call them, which I did. Before the hand–off to Center, the Departure Controller gave me a phone number to call because of a possible entry into P-56.”
We thank ASRS for this report, and for helping to underscore TapRooT®’s raison d’être.
We encourage you to use the TapRooT® System to find and fix problems. Attend one of our courses. We offer a basic 2-Day Course and an advanced 5-Day Course. You may also contact us about having a course at your site.