Piper Aircraft Corp Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 125; Flight Crew Total 6100; Flight Crew Type 30
Human-Machine Interface; Situational Awareness
Flight Deck / Cabin / Aircraft Event Other / Unknown; Ground Event / Encounter Ground Strike - Aircraft; Inflight Event / Encounter Loss Of Aircraft Control
Aircraft Aircraft Damaged; General Maintenance Action
Procedure; Human Factors; Airport
While evaluating a landing site for tundra tire equipped airplanes; the aircraft was sucked into 12-16 inches of soft powder snow after breaking through a 2.5 inch thick layer of compact snow/ice.It is common practice to evaluate landing sites by 'dragging' the tires through the upper surface; performing a go-around; and then inspecting the tire tracks to evaluate the safety of the landing site. After doing an initial pass along side of fresh snowmobile tracks; it was determined to be safe for an initial drag of the main tires through the snow. This pass consisted of 2 touchdowns. The first touchdown was normal but the second one resulted in the aircraft breaking through the upper snow/ice crust. Full aft stick and engine power were applied; but the aircraft continued to get sucked down and began to tip forward. Power was then reduced to idle in the hopes of preventing a torque roll as the propeller hit the ground. The aircraft tipped up on its nose and came to rest at approximately 120 degrees [nose down] from the horizontal attitude. There was damage to the propeller; engine and cowling in addition to the right wing strut. No one was injured and the aircraft has been determined to be easily repairable with an engine teardown/rebuild; propeller replacement; cowling work and right strut replacement.
The pilot of a PA-12 Supercruiser equipped with tundra tires attempted to test the suitability of the surface of a snow covered landing site by 'dragging' the tires through the snow on a low pass during which the tires broke through the icy surface and were sucked down into deep snow below. The subsequent damage was restricted to the propeller; the engine; the engine cowling and the right wing strut and described as easily repairable by the reporter.