Tail-first touchdown - Grampaw Pettibone - Brief Article

0 Comments | Naval Aviation News, Jan, 2002

A UH-60A crew was on a familiarization flight to regain currency in the Seahawk for the pilot in command (PIG). The pilot at the controls (PAG) was qualified and current in type. In the local operating area the PAG completed a series of maneuvers at altitude, then transitioned to a local outlying field for landing and takeoff pattern work. The aircrew completed a series of approaches and landings without incident.

After the final landing, the PAG performed an informal automatic flight control system (AFCS) "heading hold" evaluation without preflight planning, research or a flight clearance. During this evaluation a nonstandard maneuver was flown with the intent of determining the AFGS response-to-heading offset while heading hold was engaged.

On the third attempt of a nonstandard maneuver, the Seahawk rapidly diverged in yaw, driving the AFGS into an acceleration control mode vice the normal rate control mode. As the aircraft yaw rate exceeded 75 degrees per second, the flight path stabilization disconnected, leaving the left rudder pedal fully depressed. The PAG, believing a failure had occurred driving the aircraft out of control, lowered the collective to place the aircraft on the ground. The aircraft tail struck the ground first, shearing the tail wheel. The remaining tail wheel mount then dug into the runway and brought the aircraft to a rapid halt. The sudden stop broke the tail rotor gear box free and caused significant structural damage. There were no injuries.

Grampaw Pettibone says:

Unauthorized procedures caused a no-win situation during this sortie. Why didn't the PIC put a stop to the maneuvers in the first place? If the PAC had recognized the left rudder problem, he could have countered with right rudder and slowed the left hover turn. Unauthorized means "don't do it." 'Nuff said.

The following is a Grampaw Pettibone tale from yesteryear. Flight students beware!