TAP Flight 425

TAP Flight 425 was a regular flight from Brussels, Belgium, to Santa Catarina Airport (informally known as Funchal Airport or Madeira Airport; now the Cristiano Ronaldo International Airport), Portugal, with an intermediate scheduled stop in Lisbon. On 19 November 1977, the Boeing 727 operating the service overran the airport's runway before crashing onto the nearby beach and exploding, killing 131 of the 164 people on board.

Aircraft and crew
The aircraft operating flight TP425 was a Boeing 727-282 Advanced registration CS-TBR named after the Portuguese aviation pioneer Sacadura Cabral. Its manufacturer serial number was 20972/1096 and it was delivered to TAP on 21 January 1975. It was powered by 3 Pratt & Whitney JT8D-17 turbofan engines which had a maximum thrust of 16,000 lbf each. The aircraft had completed a B check on 21 September 1977, and at the time of the accident had accumulated 6,154 flying hours in 5,204 cycles.

The crew consisted of Captain João Lontrão, First officer Miguel Guimarães Leal, and Flight engineer Gualdino Pinto, as well as five flight attendants. There were 156 passengers on board.

Accident
On 19 November 1977, the aircraft operated Flight TP420 from Lisbon to Brussels, Belgium, and then Flight TP425 from Brussels to Funchal with a stopover in Lisbon. Flight 420 and the first leg of Flight 425 were completed without any issues reported. In Lisbon, the crew received the Funchal weather report. According to the forecast, severe weather was expected enroute with a chance of thunderstorm cumulus and torrential rain, but was unlikely to affect the flight.

At 7:50 pm Flight TP425 left the gate, and took off from runway 03 at Lisbon Airport at 7:55pm.

At the time of the accident, the then-Santa Catarina International Airport's runway was 1600 m long, which made landing extremely difficult.

At 9:05 pm, on the approach to Madeira, the crew of Flight TP425 requested permission to descend. The controller gave permission to descend to flight level 50 (5000 ft) at a pressure of 1013.2 mbar. At 9:05:50, the crew reported on the beginning of the descent to FL50 towards Porto Santo, and received instructions to switch to 118.1 MHz to communicate with Funchal control. At 9:17pm the crew contacted air traffic control in Funchal and reported reaching flight level 50 and the ETA at the MAD radio beacon in 5 minutes. In response, the controller gave permission to descend to a height of 3,500 feet on QNH 1013 and reported that the landing would be on runway 06. The controller then transmitted the weather report: calm wind on runway 06, wind 14 knots direction 220 at nearby Rosário, temperature 19 C, visibility 4-5 km. The crew acknowledged the transmission. According to the actual weather forecast at Funchal airport at 8:50pm, the wind speed was 6 knots - a heading of 200, visibility 5 km, cloud 7/8, rain showers, airfield pressure at runway 24: 1006 mbar, at runway 06: 1008 mbar, temperature 18-19 C.

At 9:23:13 the crew reported passing the MAD beacon at a height of 1,700 feet and a heading of 215°, while not having visual contact with the ground. Following the course of 200° and descending through 980 feet, at 9:26:33 flight TP425 reported that there was no visual observation of the runway and executed a missed approach.

After two unsuccessful attempts to land the aircraft, the crew decided to make one last try to land before they would make the decision to divert to Gran Canaria Airport in the Canary Islands.

On the third landing attempt, Captain Lontrão chose runway 24. At 9:43:52, at an altitude of 1800 ft the aircraft was reported to be flying at a rate of 205 kn, and at 9:44:57 the controller asked the crew to see if they had the aircraft's landing lights on. The crew confirmed that they were. At 9:45:02 the crew reported passing the airport's beacon and reported the runway in sight. At 9:46:48, when turning right onto a heading of 250° Captain Lontrão called for the landing checklist.

At 9:47:21 the tower reported the wind on runway 24 and asked if the crew would proceed with the landing. The crew said that they would continue. The controller subsequently cleared flight 425 to land. From a height of 400 ft at a speed of 150 kn, the plane began to descend. While on final approach to runway 24 in heavy rain, strong winds and poor visibility, the aircraft touched down 2000 ft past the threshold, and started hydroplaning. With just 3000 ft of runway left, the crew tried desperately to stop, applying maximum reverse thrust and brakes, but the aircraft slid off the runway at a ground speed of approximately 43 kn and plunged over a 200 ft steep bank, hitting a nearby bridge and crashing on the beach, splitting in two and bursting into flames.

Of the 164 people aboard (156 passengers and 8 crew), 131 were killed (125 passengers and 6 crew), making it the deadliest airplane accident in Portugal to that point. As of 2023, it is the second deadliest airplane accident in Portugal, after Independent Air Flight 1851. It remains TAP Portugal's only fatal accident since the beginning of its flight operations in 1946.

Investigation
According to the findings of the investigation, the crew was qualified for the flight. The report stated that the aircraft was in good condition after leaving the runway up until it made impact with the bridge. The report concluded that the flight crew violated the approach procedure, with the aircraft touching down 2060 ft from the beginning of the runway, which is 1060 ft farther than normal, and the speed was 148.2 kn which is, 19.2 kn higher than recommended. It was also noted that there were an insufficient number of lights of the ILS, which made it difficult to perform an ILS approach. Difficult weather conditions were mentioned as the immediate causes of the accident, due to aquaplaning on the runway, as well as an overshoot landing speed of 19 knots. The investigation recommended Funchal Airport to increase the level of meteorological observations.

Aftermath
After the accident occurred, TAP stopped flying the Boeing 727-200 to Madeira, and started flying only the 727-100, which was 20 ft shorter and took 60 fewer passengers.

The crash prompted officials to explore ways of extending the short runway. Because of the height of the runway relative to the beach below, an extension was very difficult and very expensive to perform. Between 1983 and 1986, a 200 m extension was built; 14 years later, the runway was again extended. Following the 2000 extension, the runway of what is now the Cristiano Ronaldo International Airport measures 2781 m long and is capable of handling wide-body commercial jets like the Boeing 747 or the Airbus A340.