Near-miss between JQ and Learjet

[Russell D]

Safety watchdog probes air confusion
July 18, 2008, 6:36 am

Australia's air safety watchdog is investigating a report that a US Learjet came within 60 seconds of a possible collision with a Jetstar Airbus because of confusion about uncontrolled airspace.

The incident reportedly occurred last Saturday after a section of airspace on the Melbourne to Sydney route suddenly became un monitored at 7.30am (AEST) due to an air traffic control staff shortage.

News Ltd has reported it has obtained the incident report that was lodged by the air traffic controller on duty, which states the Learjet pilot was "briefly uncontactable" because he was on a different frequency.

The incident report also states the controller was "concerned" about the risk to northbound air traffic, particularly Jetstar flight JS720.

The Civil Aviation Safety Authority has confirmed it is investigating while the air traffic controllers' union says it shows the current safety regime has unacceptable safety levels.

"Aeroplanes passing 15 miles apart may seem like a lot," Robert Mason, from the union Civil Air, said.

"But they are travelling so fast that in some scenarios there can be less than 60 seconds to react and avoid an incident."

Government body Airservices Australia says the 15 nautical mile separation was three times the required limit in that sector.

There was "no safety occurrence and no breakdown of air traffic control safety standards," a spokesman said.

From AAP

[NickN]

Government body Airservices Australia says the 15 nautical mile separation was three times the required limit in that sector

So it wasn't really a near miss then, somebody just wants to make a fuss.

[Russell D]

Ssshh...the general public don't know that!!!

The media are at it again.

[NickN]

There were simultaneous take-offs on 34L and 34R yesterday. The aircraft on 34L banked left at 600FT and the aircraft on 34R banked right heavily at 600FT. It was a near miss

Surprised we haven't seen something stupid like that in the paper. After all they were far closer than 15NM.

[Michael Mak]

Originally Posted by Russell D

Ssshh...the general public don't know that!!!

The media are at it again.

I knew it when I saw the headline on smh.com

[Philip Argy]

There could be a bit more to this than we are allowing, based on the following additional detail from The Australian:

The ESIR indicated the declaring of uncontrolled airspace on Saturday caused confusion among pilots of several aircraft.
The worst of these was when the pilot of an American-registered Learjet flying from Wollongong in NSW to Melbourne baulked at climbing up into uncontrolled airspace despite being cleared to do so. The report says the pilot failed to climb "apparently due to uncertainty with proximity traffic" in uncontrolled airspace.
As a result, the plane stayed on its course at 24,000ft, which caused it to veer into a different controlled airspace near Canberra. This alarmed controllers because Jetstar flight 720 from Hobart to Sydney was heading north at the same height, and time, through that sector.
The incident report says the Learjet was "briefly uncontactable" because the pilot was on a different frequency and that the controller was "concerned" about the risk to northbound air traffic, especially JS720.
"The two aircraft passed within 15 nautical miles abeam of each other southwest of Canberra," the ESIR said.
Mr Mason said yesterday; "Aeroplanes passing 15 miles apart may seem like a lot ... but they are travelling so fast that in some scenarios there can be less than 60 seconds to react and avoid an accident. This incident is a clear example that the current system related to (uncontrolled airspace) has an unacceptable safety level."
However, an Airservices spokesman said the 15nm separation was three times the required limit in that sector. A spokeswoman for Jetstar said the airline had not been notified about the ESIR.

What we are not told is what awareness of each other the Learjet and JQ720 had so we don't know whether the 15 nm of separation was planned or adventitious. If the Learjet did not climb into uncontrolled airspace, it follows that it remained in controlled airspace, so that at least one of the two a/c was aware of the other. At worst there was a brief period where the Learjet was not in communication with the controller of the airspace it was in. To my mind that was not the result of there being uncontrolled airspace above - it was the result of being on the wrong frequency for the controlled airspace it was in.

[Nigel C]

I think you've misread your own quote Philip.

What your quote said...

The report says the pilot failed to climb "apparently due to uncertainty with proximity traffic" in uncontrolled airspace.

It says the Lear was already in uncontrolled airspace.


And what you said...

If the Learjet did not climb into uncontrolled airspace, it follows that it remained in controlled airspace

You've suggested that the Lear was already in controlled airspace, which according to your own quote is incorrect.

Does that change your perspective at all?

[Philip Argy]

Not sure about that, Nigel - the previous sentence says the Learjet "baulked at climbing up into uncontrolled airspace despite being cleared to do so". On my reading of the story FL240 was controlled airspace but above it was uncontrolled, so the Melbourne bound Learjet remained at FL240 which was the same FL assigned to Sydney bound JQ720. What's not clear to me is whether the Learjet was directed to climb or only cleared to climb at pilot's discretion - in other words, was the Learjet where it was supposed to be or not, why was he apparently on the 'wrong' freqency, and what was in his flight plan?