The full report makes interesting reading.
- The planned flight path tracked west of Coffs Harbour through the corner of the 5500 step to the north, and the 3500 and 4500 steps to the south.
- The pilot was at 6500 and contacted ATC and requested clearance to track through the corner of the 5500 step (less than 3 minutes transit time).
- The controller (a trainee under supervision) advised clearance in class C was not available due to workload, and suggested transit through the class D airspace. There were no other aircraft in the Coffs Harbour airspace and no expected IFR arrivals or departures, however "controller performance assessment reports and daily training records included debriefing and coaching comments emphasising to trainees and controllers to be cautious with issuing clearances below A080 through the [Coffs Harbour] airspace" and the supervisor judged denying the clearance was conservative but appropriate.
- The pilot contacted the Class D controller, who asked whether he wanted to remain at 6500. The pilot said yes, so the Class D controller said to contact the class C controller for clearance.
- The pilot switches back to the Class C controller, and meanwhile the class D controller has also advised the Class C controller to expect the call.
- The Class C controller sends the pilot back to the Class D controller again. At this point I imagine the pilot stress levels are rising.
- The Class D controller says that clearance would only be available "not above 1000 feet", but doesn’t provide any tracking instructions.
- It appears that the pilot read back "not above 1000 feet" as if it were a clearance, entered the Class C and began descending. Terrain was about 3000-4000 feet.
- Shortly afterward, the pilot reported that they were OCTA at 4100 in clear conditions, and that they would be requesting clearance through the southern steps when they reached them.
- The Class D controller asked them to report entering controlled airspace.
- After a short climb they continued to descend until they crashed.
Communications between the pilot and ATC seem to be important in the context of the report. Did the pilot believe he had received a clearance down to 1000 feet, implying that there was no high ground on track? Did he believe ATC was managing terrain clearance?
A transcript of the actual radio calls would be very helpful. Times are not given for most of the events and they are discussed out of sequence. For example, the report implies that the pilot entered class C immediately after the clearance was denied and presents it as an airspace infringement, but the altitudes in the other requests suggests that it happened after the pilot read back "not above 1000 feet" i.e. he may have thought he had received a clearance requiring a descent.
Important issues are e.g.
- ATC denied clearance due to workload for no obvious reason - there were no other aircraft in the airspace.
- Pilots need to maintain awareness of terrain clearance and not assume that ATC are protecting them even if they have received a clearance or instructions.
- ATC need to be alert for pilots reading back things that are not meant to be clearances or instructions and clarify if necessary.
The big question is whether the presentation in the report (no transcript, events out of order) is deliberate obfuscation to make it difficult to understand the role of ATC in the accident.