Safety - Are step-down approaches unsafe?

FAA, NTSB Remain At Odds On 'Dive And Drive' Instrument Approaches

A type of non-precision instrument approach composed of a series of step-down altitudes, informally known as "dive and drive," remains a point of contention between the FAA and NTSB following the August 2013 crash of UPS Flight 1354 in Birmingham, Alabama.

To date, the FAA has refused an outright ban on the technique, despite nearly a decade of pressure by the NTSB. UPS separately says it plans to prohibit the practice in its pilot manuals.

In the Birmingham crash, the crew of the Airbus A300-600 freighter had intended to use a more precise non-precision instrument approach technique known as a constant descent final approach (CDFA), but the captain ultimately resorted to a dive and drive approach late in the arrival. The aircraft hit terrain approximately one mile short of the runway, killing both pilots.

The NTSB issued 15 recommendations to the FAA following the crash, including one recommendation calling for the agency to prohibit dive and drive approaches, a recurring theme in the NTSB's crash investigations.

The NTSB first asked the FAA to "develop and encourage" the use of CDFA approaches at all airports served by commercial carriers after an American Airlines MD-80 struck trees while on a dive and drive approach to Bradley International Airport near Hartford, Connecticut, in 1995.

After a Korean Airlines Boeing 747-300 crashed on approach to Guam in 1997 using the same approach technique, the NTSB asked the FAA to address the equipment and training needed for CDFAs. The FAA's response to both recommendations was considered satisfactory and the issues were considered closed.

However, a controlled-flight-into-terrain crash of a Corporate Airlines Jetstream 32 turboprop on a dive and drive approach into Kirksville, Missouri, in 2004, prompted an NTSB recommendation to ban dive and drive techniques altogether, a plea that was superseded by the UPS recommendation.

The FAA does not agree, stating that while a CDFA is the "preferred method" of accomplishing a non-precision approach, dive and drive use should not be prohibited. "In certain situations, primarily dependent on weather conditions and runway alignment in combination with runway visibility, a dive and drive maneuver could benefit an operator," the FAA wrote in its December 2014 final response to the recommendation, noting that potential problems with the technique are spelled out in an Advisory Circular.

"Dive and drive is prudent and safe when done correctly and under appropriate circumstances." Based on the response, the NTSB recently closed the recommendation as "unacceptable action."

UPS, however, appears to be heeding the NTSB's advice. Houston Mills, UPS director of safety, said in a December letter to the NTSB that the carrier is in the process of "explicitly prohibiting dive and drive maneuvers" in its manuals.