Pakistan Cargo Crash: Families Plead for Global Help to Retrieve Black Boxes from Deep Sea

Relatives of the five crew members aboard a Boeing 737 cargo plane that crashed into the Arabian Sea off Pakistan on July 7 are urging an international search effort to recover the flight recorders. The black boxes could reveal the cause of the crash, but the water depth of about 3,000 metres (9,800 feet) makes recovery challenging and costly.

Debris from the K2 Airways freighter was recovered soon after the crash, but finding the black boxes would require an underwater search likely needing foreign assistance, according to aviation experts familiar with deep-water crashes such as Air France 447 in 2009. The plane's locator beacons, designed to transmit for only 30 days, have limited the window for recovery.

Recovering the recorders could clarify whether a navigation system issue reported shortly before the crash was linked to a component that relatives say was replaced before the flight. Pakistan has provided no public update on the search for a week, and an industrial company with underwater search expertise told Reuters it had not heard of any requests by Pakistan for assistance from foreign companies or navies.

“The search has to continue, and whatever resources can be deployed, locally and internationally, should be deployed,” said Yashib Rizwan, eldest son of Captain Rizwan Idris. “For us a transparent investigation is key.” Engineer Muhammad Arif Siddiqui’s son, Abdur Rafay Siddiqui, also called for international assistance if needed. Both families have held funeral prayers after losing hope the bodies would be recovered.

Pakistan’s government has not responded to questions about whether it will seek foreign assistance. K2, which lost its only plane in the crash, has not responded to requests for comment.

The pilots reported a navigational system issue at 9:18 p.m. Pakistan time while flying from Sharjah in the United Arab Emirates to Karachi, according to Pakistan’s airports authority. Local air traffic control tried to guide the plane, but three minutes later radar showed it descending rapidly and communication was lost. Flightradar24 data indicated the plane plunged about 5,000 feet in less than a minute, climbed about 6,000 feet in 30 seconds, and then entered a catastrophic dive from 36,550 feet.

Ghulam Nabi, father-in-law of co-pilot Faisal Jatoi, said the plane spent about 10 days in Sharjah awaiting a replacement part after a maintenance fault. One of the plane’s two inertial reference units (IRUs), which feed information on the aircraft’s position, speed, and orientation to the cockpit displays, was replaced in Sharjah, according to captain’s son Yashib Rizwan. John Goglia, a former U.S. National Transportation Safety Board member, noted that if the IRU is faulty, pilots cannot rely on instruments, and flying at night over the ocean without visual references could be perilous.

Aircraft accidents are usually caused by multiple factors, and it remains unclear whether the IRU replacement is related to the crash. An inertial reference system malfunction contributed to the 2007 Adam Air crash in Indonesia, where pilots became fixated on troubleshooting erroneous information, failed to notice a steep right bank, and lost control, killing all 102 aboard. In that case, pings from the black boxes were detected three weeks after the crash in a search aided by the U.S. Navy, but recovery from about 2,000 metres of water took months and millions of dollars using a specialised remotely operated vehicle.

U.S. aviation expert Todd Curtis said on the “Flight Safety Detectives” podcast that Pakistan was unlikely to mount a similar recovery operation unless there was a compelling reason, given the K2 plane was an ageing cargo jet.