Mid-air horror as plane nose-dives after electrical fault on departure from Heathrow

Mid-air horror as plane nose-dives after electrical fault on departure from Heathrow The Boeing 747-433 was forced into a dangerous descent after water and ice compromised the aircraft's internal heating system, freezing tubes as frantic crew sounded the alarm A hero pilot kept a troubled aircraft in the sky after an on-board electrical fault forced the jet to nose-dive. The Boeing 747-433 ran into trouble following its departure from London Heathrow, bound for Hong Kong International Airport. Unwanted water and ice from outside the aircraft had managed to get inside, playing havoc with the air conditioning. The problem was only discovered when the plane was in the air, and it suffered a number of potentially catastrophic electrical issues, which began during take-off. It was quickly found that the tube heating - a powerful electric element used to measure airspeed - had become frozen. Frantic crew attempted to resolve the sudden failure before issuing a PAN, an urgent safety alert that requires priority handling from Air Traffic Control, a report by the Air Accidents Investigation Branch revealed. But the tubes had frozen, which forced the pilot into a dangerous descent. A mayday was declared as the cargo plane was pitched nose-down at approximately 12,000ft to regain indicated airspeed. The plane later landed safely at Amsterdam Airport Schiphol, the main international airport of the Netherlands. The AAIB carried out a detailed investigation into the incident on February 8, 2024 and made public its safety recommendations. The report stated: "The aircraft suffered numerous electrical issues which began during the takeoff roll and worsened during the climb. These were caused by the loss of AC electrical buses 1 and 4, which resulted in multiple failure messages for the flight crew to manage as well as the loss of all pitot tube heating. "The flight crew carried out numerous, concurrent checklists to deal with the system failures, declared a PAN and started to divert to Amsterdam Schiphol Airport. "When a pressurisation issue caused the crew to initiate a descent, the aircraft entered icing conditions and the pitot tubes froze, resulting in all three airspeed indicators indicating an erroneously low airspeed. The autopilot remained engaged and pitched the aircraft nose-down to regain indicated airspeed. "The pitch reached 7.6° nose-down with an associated 6,240 ft/min descent rate, before the aircraft exited icing conditions, correct airspeed was regained and the autopilot pitched up. The descent had resulted in an 18 kt overspeed." The AAIB announced the outcome of their long investigation today. The aircraft accidents and serious incidents watchdog found that ice and water were to blame as the aircraft suffered numerous electrical issues, which began during departure and worsened during its climb. They noted that there had been previous "events of water ingress" on the aircraft and set out its four recommendations, which including introducing measures such as installing a fibreglass reinforcing overcoat.