Has anyone considered if the below FAA Airworthiness Directive could be a clue the MH370 investigation?
SUMMARY: We propose to adopt a new airworthiness directive (AD) forcertain The Boeing Company Model 777 airplanes. This proposed AD was prompted by a report of cracking in the fuselage skin underneath the satellite communication (SATCOM) antenna adapter. This proposed AD would require repetitive inspections of the visible fuselage skin and doubler if installed, for cracking, corrosion, and any indication of contact of a certain fastener to a bonding jumper, and repair if necessary. We are proposing this AD to detect and correct cracking and corrosion in the fuselage skin, which could lead to rapid decompression and loss of structural integrity of the airplane.
The antenna covered by the pending AD was not installed on MH370, so that airplane is not subject to the AD or the related Service Bulletin.
So, it has been determined that the AD was not relevant to this plane. However, it served as the key inspiration for an alternative explanation.
- Likely fuselage failure near SATCOM antenna adapter, disabling some or all of GPS, ACARS, ADS-B, and ADS-C antennas and systems.
- Thus, only primary radars would detect the plane. Primary radar range is usually less than 100nm, and is generally ineffective at high altitudes.
- Also explains why another Pilot thirty minutes ahead heard “mumbling” from MH370 pilots.
- (VHF comms would be unaffected by SATCOM equipment failure.)
- The plane was [UPDATE: WAS NOT] equipped with cellular communication hardware, supplied by AeroMobile, to provide GSM services via satellite. However this is an aftermarket product; it’s not connected through SATCOM (as far as I know).
- [UPDATE]: However, if the plane flew over or near land, then cellular connectivity is still possible.
- Interestingly, 19 families signed a statement alleging they were able to call the MH370 passengers and get their phones to ring, but with no response.
- When Malaysian Airlines tried to call the phone numbers a day later, the phones did not ring. By this time, fuel would have been exhausted.
For all 3 types of (slow, moderate, extremely-rapid) decompression, there is substantial danger to the crew and passengers.
However that first instinct is completely wrong. It takes a surprising amount of training to instill into pilots that what they *need* to do first is put on oxygen masks. To train airline pilots, we often put them into a pressure deprivation chamber, simulate a gradual decompression, and follow up with oxygen breathing from a bottle. Many pilots say they notice an astounding difference in mental performance once they start the oxygen.
- Investigators should obtain data logs from primary radars throughout mainland China that would have been along the planned route. They may be the best clue as to the trajectory of the aircraft.
- Investigators should obtain all passengers’ cell phone log and location data. The timing of the last successful cellular connection (ring/SMS/data-packet) can predict how long the plane was in the air. iPhone/iOS location (GPS) data may be available from Apple if subpoenaed. Android location data may be available from Google.
- Add a secondary search space to include a 300nm+ radius around Beijing, focusing on surrounding bodies of water. Using planned routing trajectory, known autopilot logics, fuel quantities, and weather patterns, it may be possible to define a smaller 50nm * 50nm search space. Consider running the above scenario in MH’s 777-200ER full flight simulator.
- Boeing should provide expertise about fuselage/antenna design and autopilot/navigation logic, so as to help plot this second search space.