What happened
On July 24, 1991, the Piper PA-34-220T CS-ARM departed Santa Maria Airport in the Azores for a flight to Santa Catarina Airport in Funchal, Madeira. The aircraft carried two crew members and had approximately four hours of endurance. At 18:50, the plane took off with a filed flight plan. Throughout the cruise, communications were normal, with position reports made at IRKID and IRSAN waypoints.
Upon approaching Funchal, the crew reported seeing the runway at 22:13 and initiated a turn to base leg for Runway 06 at 22:15. Air traffic control authorized the landing with wind information indicating calm conditions and light swell. However, radio contact was lost immediately after this transmission. The aircraft never entered final approach. Search and rescue operations began four minutes after the expected arrival time. Debris, including parts of the nose gear and a headrest, were found approximately three nautical miles from the coast the following morning.
The investigation
The GPIAAF investigated the disappearance of CS-ARM, noting that the aircraft was not equipped with a Cockpit Voice Recorder or Flight Data Recorder. The only recoverable wreckage consisted of the right main landing gear and the nose gear, which exhibited brittle fractures consistent with sudden static overload from striking water at high speed.
Meteorological data from Funchal indicated visibility greater than 10 km, clouds at 2,000 feet, and calm seas. The investigation highlighted the unique challenges of operating in Madeira due to its orography. Specifically, the runway is situated parallel to the coastline over the sea. On calm nights, lights from the adjacent hillside reflect off the water surface, creating a mirror effect that can duplicate visual references.
The report noted that neither pilot had specific experience with night approaches to coastal airports with characteristics similar to Funchal's Santa Catarina Airport. While private flight regulations did not mandate prior training for this specific aerodrome, the complexity of the approach required specialized knowledge.
Findings
The accident was caused by the aircraft colliding with the sea during the final phase of the approach. The most critical factor was spatial disorientation resulting from visual illusions. It is highly probable that the pilots abandoned instrument references, particularly the altimeter and variometer, relying instead on visual cues distorted by light reflections on the calm water.
Forensic analysis of the landing gear fractures indicated that the right main gear struck the water first with significant force, causing the aircraft to roll to the right before sinking. The left gear likely remained intact but was lost to the depths along with the rest of the airframe. The crew, consisting of a commander with 76 hours total experience and a second pilot with 305 hours, both perished in the incident.
Safety action
The report emphasized that the topographical conditions of Madeira require specific operational requirements and prior training for pilots commanding aircraft at Funchal Airport. It highlighted that existing regulations for private operations did not adequately address these specialized risks.