Indonesian authorities confirmed Wednesday that the angle of assault (AOA) sensor was changed after a flight from Manado, in North Sulawesi to Denpasar, Bali on October 28. The Boeing 737 MAX eight then made one other flight to Jakarta that very same day, and the pilots reported additional issues.
All 189 individuals on board Flight 610 died when the brand new Boeing 737 MAX eight crashed into the ocean on October 29, 13 minutes after taking off from Jakarta on a brief flight to Pangkal Pinang on the Indonesian island of Bangka.
Seek for voice recorder
Nearly two weeks after the crash, authorities are nonetheless trying to find the airplane’s cockpit voice recorder (CVR), which is believed to be buried beneath deep mud. If discovered, it ought to reveal what occurred within the cockpit within the ultimate seconds of the flight.
Investigators are already analyzing the flight information recorder that was pulled off the ocean mattress, some 30 meters beneath water, on November 1.
KNKT is sending a dredger to assist with the seek for the cockpit voice recorder. It is anticipated to succeed in the crash website within the subsequent two days. After initially listening to a “ping” from the recorder on Saturday, diving groups can not detect a sign from the machine.
“Our impediment is thick mud that is buried the CVR,” mentioned Haryo Satmiko, deputy head of the KNKT. “With this particular ship we are going to suck the mud there after which sweep the realm.”
Investigators are persevering with to interview the pilots, crew and technicians who have been concerned within the earlier flights made by the plane within the days previous to the crash.
Unscrambling the jargon
In its assertion on Wednesday, Boeing mentioned that the Indonesian transport committee had indicated that Flight 610 had “skilled faulty enter from one in every of its AOA sensors.”
An AOA sensor is an instrument, just like a small wind vane, that sits exterior the airplane just under the cockpit and sends data to its computer systems in regards to the angle of the airplane’s nostril relative to the oncoming air. The sensor helps to find out whether or not the airplane is about to stall and dive.
“It is extremely essential as a result of it tells them if the airplane is flying at a too-high angle of assault, which may result in an aerodynamic wing stall (lack of raise),” mentioned aviation analyst and editor-in-chief of Airlineratings.com, Geoffrey Thomas.
CNN’s aviation correspondent Richard Quest mentioned the plane receives data from the sensors and responds accordingly.
“The airplane’s computer systems have been getting faulty data from exterior sensors. That triggered them to do sure issues similar to push the nostril down. The one approach you possibly can deal with that is to change the pc off,” he mentioned.
Issues with air velocity indicators
The airspeed indicator is sort of a speedometer and tells the pilot how briskly the airplane is shifting via the air. It does this by gathering information from the airplane’s pitot tube and the static port, which primarily examine differentials within the air strain to reach on the airplane’s velocity and the altitude.
After issues have been reported with the air velocity indicator, the AOA sensor was changed by a Lion Air technician in Bali earlier than the airplane departed for Jakarta on its penultimate flight.
As soon as in Jakarta, a Lion Air technician checked the airplane once more and gave it the inexperienced gentle to fly on its ultimate flight, from Jakarta to Pangkal Pinang.
Lion Air Group Managing Director Captain Daniel Putut Kuncoro Adi advised CNN on Wednesday that Lion Air strictly follows Boeing’s steerage for working the 737 MAX 8s, as specified by the upkeep handbook e-book.
“Pilots write within the logbook about the issue they’d within the flight, then our technicians repair it and write (what) they did within the logbook,” mentioned the managing director, including that technical conversations between pilots and technicians concerning the plane are written and signed in a doc referred to as the Plane Flight and Upkeep Log.
Quest says investigators will probably be taking a look at a mix of things that would have triggered the crash.
“A crash is all the time a sequence of occasions. Basically the problem goes to be how these pilots flew the airplane because the situations arose,” he mentioned.
What does Boeing and the FAA say?
On Wednesday, Boeing mentioned it had issued an “Operations Handbook Bulletin” advising airline operators learn how to tackle faulty cockpit readings.
A spokesperson for the plane producer would not confide in CNN whether or not the directive was issued to operators of all Boeing plane, or simply those that fly 737 MAX eight planes, the identical mannequin as Flight 610.
The directive factors operators “to present flight crew procedures to handle circumstances the place there may be faulty enter from an AOA sensor,” the assertion mentioned.
Following Boeing’s bulletin, the Federal Aviation Administration (FAA) on Wednesday issued an airworthiness directive to Boeing 737 MAX eight crews in the event that they expertise the identical issues that introduced down Lion Air Flight 610.
“These faulty inputs can doubtlessly make the horizontal stabilizers repeatedly pitch the nostril of the airplane downward, making the plane troublesome to manage,” the directive mentioned.
It continued that, “The FAA has alerted affected home carriers and international airworthiness authorities who oversee air carriers who use the 737 MAX.”
The FAA directive doesn’t acknowledge a difficulty with the whole fleet of 737 MAX eight airplanes and there have been no reported comparable points within the US.
Boeing mentioned it’s concerned within the ongoing investigation with KNKT and different authorities authorities into the Lion Air crash and “continues to cooperate absolutely and supply technical help.”
CNN’s Jo Shelley, Bianca Britton, Rene Marsh and Gregory Wallace contributed to this report.