What happened
On October 28, 1972, at approximately 19:05 local time, a Piper PA-12 Super Cruiser with registration CS-ADW, operated by the Aero Club of Portugal, sustained significant damage after departing the runway at Tires Aerodrome. The aircraft was conducting a local flight with one pilot and two passengers aboard. The pilot, a 21-year-old with limited experience, had departed from Cascais Aerodrome earlier that evening.
During the approach to Runway 17 at Tires, the pilot executed a go-around before attempting a second landing. Upon touchdown, the aircraft appeared to land relatively normally but began to bounce intermittently. The pilot applied intermittent braking and made small directional corrections. Subsequently, the left wing rose, and the aircraft began to yaw definitively to the right. The pilot reduced power, but the aircraft departed the runway, crossed a drainage ditch, and overturned on the irregular terrain on the other side.
The investigation
The General Directorate of Civil Aviation (DGAC) established an inquiry commission to examine the circumstances. The investigation confirmed that the aircraft was airworthy, with valid certification and maintenance records up to the date of the incident. The Lycoming O-235 engine and Sensenich propeller showed damage consistent with a high-ratio impact with the ground, but no pre-existing mechanical failure was identified.
The pilot stated during interviews that he had lost track of time and inadvertently entered the night flying period without holding a night rating. He admitted to being distracted and unable to explain the specific handling errors during the landing roll. Witnesses observed the aircraft departing the circuit without instructor consent and noted the poor visibility conditions as twilight faded.
Findings
The inquiry concluded that the accident was caused by poor pilot operation resulting in a loss of directional control, exacerbated by several contributing factors:
- Pilot Inexperience: The pilot lacked sufficient experience and did not hold a night rating, yet flew during the period defined as night.
- Visual Conditions: The flight occurred during advanced twilight with diminishing light, which impaired depth perception and situational awareness.
- Runway Environment: The Tires Aerodrome had a very small lateral safety area on the western side of the runway, leaving no margin for error if the aircraft departed the paved surface.
One passenger sustained minor abrasions to the nose; the pilot and the other passenger were uninjured. The aircraft suffered severe structural damage but was deemed repairable.
Safety action
The inquiry recommended that the pilot undergo appropriate training and verification by the competent authority. It also advised that pilots should not conduct night flights, especially with passengers, unless they meet specific regulatory requirements for night operations. Additionally, it was recommended that the western side of the Tires runway be equipped with an adequate safety area to prevent similar incidents.