• Interim report finally released by the German BFU
  • Flight Service Bureau version of events confirmed
  • New pictures released by the investigators

Back in March, FSB covered a major wake turbulence upset experienced by a Challenger 604 after passing an A380.  After our initial story was published, it was covered in various versions in The Times of London, Flying magazine, AIN Business Aviation News,  Deutsche Welle, and NBC. The picture on the Flight Service Bureau facebook page was viewed 1.1 million times.

From the interim report, these facts are confirmed:

  • The incident was caused by the wake from an Airbus A380 at FL350
  • The Challenger 604 passed directly underneath the A380 at FL340
  • The wake encounter occurred 48 seconds after the cross – when the two aircraft were 15nm part
  • The Challenger initially rolled 42 degrees to the right, then 31 degrees left, and experienced G-Loads of 1.6g positive followed 1 second later by -3.2 g.
  • It lost altitude from FL340 to FL253 over a 2 minute period – loss of 8700 ft.

In an interview, the crew said:

The airplane shook briefly, then rolled heavily to the left and the autopilot disengaged. [We] actuated the aileron to the right in order to stop the rolling motion. But the airplane had continued to roll to the left thereby completing several rotations. Subsequently both Inertial Reference Systems (IRS), the Flight Management System (FMS), and the attitude indication failed”

“… since the sky was blue and the ocean’s surface almost the same colour [I] was able to recognise the aircraft’s flight attitude with the help of the clouds

The BFU published the FDR excerpt above, and a full interior picture of the cabin, post event.

 

Flight Service Bureau has issued guidance to OpsGroup members, in Note to Members #24 (March 19th, 2017), which can be downloaded publicly here. The highlights are:

  • As Aircrew, use SLOP whenever you can.
  • As Controllers, be mindful of smaller aircraft passing underneath A380’s.
  • Avoid flying the centreline if you can. SLOP 0 is not an offset. Choose 1nm or 2nm.
  • Note the new SLOP rules from ICAO in the 16th edition of Doc 4444.
  • Expect guidance from EASA and the FAA to follow

With very recent updates to both NAT Doc 007 and ICAO Doc 4444, the rules for SLOP are a little different than before.

 

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