Problems Found in Crashed Jet’s Airspeed Indicator

KOMPAS/RIZA FATHONI

Relatives of the victims of the Lion Air aircraft, registered as PK-LQP, attend a press conference in Jakarta on Monday (11/5/2018). The press briefing disclosed the latest developments in the search-and-recovery operation for victims and debris from Lion Air flight JT610, which crashed into the Java Sea on Oct. 29.

JAKARTA, KOMPAS -- On the eighth day since the crash of Lion Air flight JT-610, aircraft registration code PK-LQP, the National Transportation Safety Committee (KNKT) said that it had found problems in the aircraft’s airspeed indicator system. The KNKT said that, in its joint investigation with the US National Transportation Safety Board and aircraft manufacturer the Boeing Company, it had found that technical problems had occurred in the aircraft’s last four flights.

“Of the 19 flights recorded in the flight data recorder [FDR], we found problems in the airspeed indicator in the last four flights,” KNKT head Soerjanto Tjahjono said in Jakarta on Monday (5/11/2018).

Soerjanto said that he could fully ascertain that, in line with FDR data, there had been a technical problem with the aircraft during its Denpasar-Jakarta flight, prior to its Jakarta-Pangkalpinang flight, during which it crashed into the sea. The technical problem was in the aircraft’s airspeed indicator.

Before an aircraft is declared flightworthy, the pilot makes a written list of problems he has detected with the aircraft. Technicians then look at the list and make necessary repairs, of which they will make a note. Once all repairs are done according to the manufacturer’s standard procedures, the aircraft will be declared flightworthy.

“We are still trying to find out where the problem lies. It may be with the speed sensor, which produces data for other equipment. [A problematic speed sensor will render] readings in other equipment inaccurate. This may hinder the pilot from understanding the airplane’s real conditions,” KNKT air crash investigation sub-committee head Nurcahyo Utomo said.

He said problems in the aircraft’s airspeed indicator would be an anomaly. No other airplane has ever suffered from such a malfunction.

“So far, we have yet to find any other problems. We will stay focused in our investigation into what caused the problem. We regard this airspeed indicator problem as a malfunction,” Nurcahyo said.

Damage to the display that the pilot and co-pilot use in the cockpit, to cables, computer or inner sensors could have led to the airspeed indicator problem.

Recovered aircraft debris shows that the aircraft crashed into the sea at a high speed. “This shows that the engines were functioning and exerting a huge amount of energy at the moment of impact,” Soerjanto said when explaining about the recovery of victims’ remains.

Currently, the KNKT is gathering data on the aircraft’s repair history, especially during the period when the problems existed. KNKT investigators will study details of the aircraft’s history, including interviewing pilots on previous flights and technicians involved in repairing the aircraft.

“We have interviewed the plane’s pilot during its Denpasar-Jakarta flight. This week, we plan to interview the pilot that flew the plane from Manado to Denpasar,” Nurcahyo said.

Search for CVR

As of Monday, the joint search and rescue (SAR) team was continuing its search for the downed aircraft’s cockpit voice recorder (CVR), apart from searching for and identifying victims’ remains.

A dive team from Navy’s elite Frogmen Command (Kopaska) was deployed from the Tanjung Pakis post in Karawang, West Java, on Monday. The team successfully retrieved 19 bodies along with debris.

“When the team was at a depth of 31 meters, its sonar detector picked up what we believe to be signal from the CVR. However, it later disappeared,” said Kopaska commander Col. Johan Wahyudi of the Navy’s Fleet Command I.

On Tuesday and Wednesday, the dive team will intensify its search in the area where the CVR signal was detected. Search efforts will be conducted from 7 a.m. to 5 p.m. “We will optimize this extended search period to retrieve the CVR and find victims’ remains, both on the surface and underwater.,” Johan said.

The KNKT had also pledged to retrieve the CVR. “I do not want the CVR to be irretrievable. I will do everything in my power [to retrieve it],” Soerjanto said, adding that the KNKT would still continue its search after the end of the extended search period.

Retrieving the CVR will be important in finding out what happened in the cockpit in the moments leading to the crash and obtaining a fuller picture of how the disaster could have occurred.

Victim identification

As of Monday evening, the National Police’s disaster victim identification (DVI) unit had identified 13 bodies through fingerprint scans and DNA testing.

Combined with the 13 bodies identified last week, 27 bodies have been identified so far out of the downed flight’s 189 people on board.

“Even after the search period is over, we will continue the victim identification process. We will continue to hold reconciliation sessions until all 189 people on board the plane have been identified,” the police’s DVI unit head Adj. Sr. Com. Lisda Cancer said. As of Monday evening, the unit had received 137 body bags.

In Pangkalpinang, the first identified remains of a Bangka Belitung-based JT-610 passenger, Karmin, 68, arrived at Depati Amir Airport on Monday morning. Families were still waiting for the other 55 Bangka Belitung-based disaster victims.

National Search and Rescue Agency (Basarnas) head M Syaugi told reporters that the search and rescue effort, which is currently in extension until Wednesday, may be further extended. “Hopefully with these extra three days, we can retrieve more bodies and send them to the National Police hospital. We will not stop,” he said.

On Tuesday, Transportation Minister Budi Karya Sumadi is scheduled to participate in joint prayers and the laying of flowers on the sea off the coast of Karawang in West Java. (E01/E02/E03/E04/E05/E12/E16/E18/E19/E20/E22/ARN/TAM/RTG/RAM)