Merged: Mid-air collision at Moorabbin

[Capt Wally]

Lets hope that some good will come of this event by way of education for perhaps foreign students who 'seem' to have less of a graft of the requirements. And to those that are teaching them



CW

[MerlinV8]

PlankBlender

I have very strong veiws on this checkout my earlier thread http://www.pprune.org/professional-p...ts-vh-pzh.html

[Di_Vosh]

Merlin, it's a pity then that you deleted the thread.

Just because the prevailing opinion went against you, doesn't mean that you should delete the thread. It also doesn't mean that you were wrong.

All I did was to point out an alternate viewpoint on the issues that you saw, and it had very relevant information on it, IMHO.

My 2c.

DIVOSH!

[Mark1234]

Does anyone know if ATC alerted the circuit traffic and the incoming pilots about the student pilot that had just completed a touch and go without talking on the radio (and for that matter without a clearance.. fatal error )?

Hang on, do we really read that as UPY not having any communication with tower? given that UPY originated from MB, it's fairly unlikely - I simply read that as UPY not having conversed with the tower since the (presumably cleared) touch and go. That would not me unreasonable, downwind being the next circuit call. It does however clarify that there were no additional instructions such as an early turn etc.

[PlankBlender]

The pilot of VH-UPY conducted a touch and go on runway 31L, but there was no radio communication between the pilot and the control tower.

I read that as him not having been cleared, because otherwise it's a non-sensical and superfluous statement for the reason you point out, Mark.

And in a report like this, I would expect not to find superfluous statements, especially if they directly relate to a possible cause or contributing factor of the accident.

Makes sense to a degree actually, would have to be not an uncommon thing for a nervous solo student pilot to turn the volume or squelch down inadvertently (between circuits, i.e. he probably would have talked to the tower before) and then concentrating on the touch and go, forgetting to wonder about the missing radio calls/clearances.. Radio failure is also a possibility, albeit a remote one, probability is he would have made the landing a full stop in that case.

Unless anyone in the know wants to share some information they have that goes beyond what is currently published, we'll probably just have to wait for the final report..

I find it strange, however, that in the Airspace section of the report, they talk about ALERT broadcasts of the tower as one of their responsibilities, but then in the main section, there is no mention of any warning given to conflicting traffic (assuming the solo student wasn't talking). I think what isn't in the report speaks louder at this time than the statements they make, which again wouldn't be surprising for a prelim report...

The flight paths look too straight and predictable for the tower not having picked up on the possible collision course, given they knew the inbound height and the fact that the circuit student was solo

The other thing that surprised me was this:

As VH-CGT approached the circuit pattern, the student pilot saw VH-UPY, very close and climbing from his left on a collision course, and took avoiding action by turning hard right and descending.

I really wonder what the instructor was doing, not seeing the traffic in time and taking action in time to avoid the collision in the first place, but I guess reasons for that could be manifold, and I am sure said instructor has since contemplated his priorities at the time more than once

[kookabat]

not seeing the traffic in time

*Blatant speculation*

PPL sitting in LHS. Instructor sitting in RHS. Low wing on a Cherokee.

I wouldn't expect to be able to see much in the area to the left, below and ahead of a Cherokee from the right hand seat.

[PlankBlender]

I knew that someone would pounce on that one

Probably should have said "not seeing the traffic ahead of the student", same same really..

Am I wrong to expect that the instructor should have known about the traffic in the circuit from monitoring the radio transmissions on approach, and should have seen and/or expected (depending on actual radio calls made, details of which seem unclear at this time) the Cessna coming up from the runway, and should have consequently seen the conflicting plane while it was still ahead of them rather than under the wing off to the side, enquiring with the tower about said traffic if it couldn't be spotted?

You can't tell me instructors just fly into one of the busiest GAAP's in the country without having traffic sorted out in their heads and having a plan in case there is potentially conflicting traffic??

[VH-XXX]

It only takes some basic fact finding and a look at the map of the crash site to realise that the aircraft with instructor doesn't appear to be in the correct location considering that runway 31 was in use. Had 35 been in use the instructor aircraft would have been in the appropriate location for approaching from the north. Simple stuff really and worth a closer look.

[PlankBlender]

XXX, are you saying the diagram in the prelim report is wrong? It doesn't leave much room for interpretation as to the location of the crash. Can you maybe furnish more details?

So apart from not knowing traffic, you are saying the approach profile was wrong, very close to the aerodrome?

My first hand experiences with more than one RVAC instructor have been bad to the point of me cutting my losses and seeking alternatives (glad I did!), the more data I get about this organisation, the more doubts I have on its leadership

[blackburn]

The track shown on the ATSB map for VH-CGT indicates the acft may have been asked to report at the Moorabbin Oval, the origin of the track shown on that map. This is a frequent request by MB ATC for acft joining the circuit after reporting inbound at Brighton, one of the complusory approach points for Moorabbin Aerodrome.
Therefore the postition of CGT as shown would be fairly normal for joining downwind for RWY31L. The position of UPY would also have been most likely correct, but the problem seems to have been that of a climbing acft being seen against a background of housing etc. by the inbound PA28 crew in sufficient time to take more avoiding action than they did.
This is not withstanding the apparent lack of radio comms by UPY and the situational awareness by the inbound PA28 crew of all the relevant circuit traffic. The pilot of UPY with his limited experience may have been only concentrating on his own circuit and height to the exclusion of almost all other considerations.
My assumptions based on a bit of knowledge of Moorabbin procedures.
Blackburn

[VH-XXX]

The tracks seem too perfectly square to be correct and the damage that entailed as a result of the collision doesn't match closely the approach paths of the aircraft even taking into consideration any evasive action taken.

[Mark1234]

Equally, had UPY got off the ground and into the circuit without radio calls, I would expect that, or the point at which he went silent to be mentioned - I'd expect a bigger deal to be made. Basically it's ambiguous - which was the point I intended to make, even if I put my 'reating between the lines' interpretation on it.

I see nothing wrong with the tracks/positions, though they're obviously representative, rather than radar traces. I admit I'm confused by the damage / reported contact vs the diagrammed positions and avoiding action, but it also seems that some folks have a version in their own heads, and the prelim is insufficient to draw firm conclusions from. Accordingly I shall disappear again and await the full report.

[Sunfish]

I think you had better wait for the transcript of the relevant Tower frequency 123.0, and some idea of the Tower workload at the time. It can get mighty busy at YMMB sometimes, you can get over transmission, there are people learning their voice procedure and refining their pronunciation as they go, and in my opinion the controllers do a great job under lots of pressure.

A tragedy for all concerned in more than one way.