Melbourne Coastal Route / YMML Runway 34 GBAS
I think I raised the issue of Hobson bay some years ago. There are helicopters, light aircraft and the occasional seaplane in that area and we are asking for trouble. my solution is a traffic separation scheme with east/west lanes.
If I’m not mistaken, QF 94 makes this approach almost every morning at 8:30am.
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From memory, a 3 degree path requires a descent from 3000ft just passed AKDEL (~0.3nm). So AKDEL is about in the position to be on profile at 3 degrees. Typical turn radius for a 90 degree turn is about 2nm at that point (note 185kt speed restriction). This means that aircraft will not be established on the final approach path (ie complete the turn) until after the profile descent point. For an RNAV approach this is OK. For a precision approach this is not.
Is there any advantage to ATC and/or airlines doing a straight in precision approach from further out rather than the turn at 2500? Just wondering whether there will be pressure to use that approach, given it is on the chart.
The AIC says "the GLS approach will become the preferred instrument approach to Runway 34. The earliest this could occur is 6 December 2018." I'm not sure whether that goes along with the idea that it will not be common.
Aircraft will be flying the same route they always have. The only difference is if they are flying the GLS approach, they may be 500 feet lower than the RNAV or VOR approach.
The only aircraft that do GLS approaches are A380 A350 B787 and some 737-800's (Qantas only I believe).
The only aircraft that do GLS approaches are A380 A350 B787 and some 737-800's (Qantas only I believe).
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A GLS could start 30 nm and be totally curved with no level segment.
Be careful what you wish for as they could have easily put it to ground level and routed you to the south around or over Point Cook.
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I vote for 60 kts circles over Sunfish's boat at 2500 ft.
Part of the issue is starting ILS approaches so far away from the runway. Alot of noise/airspace problems around Australia would be resolved by just having shorter approaches. Especially with a STAR delivering you to a intercept point, 10 mile finals are just a waste of fuel. In this instance if the STAR lined you up at 5.5 miles it would solve a few issues.
Last edited by neville_nobody; 18th Oct 2018 at 01:56.
Those worried about 500FT vertical separation, have a look at ERSA for Sydney's chopper and Victor One VFR routes.
Been in for years.
Essendon airspace and traffic as well as the height of the CBD buildings are limitations.
Also the noise associated with manoeuvring closer in over built up areas is a factor. These days any changes to and new SID/STAR procedures have to pass stringent environmental assessment.
Been in for years.
In this instance if the STAR lined you up at 5.5 miles it would solve a few issues.
Also the noise associated with manoeuvring closer in over built up areas is a factor. These days any changes to and new SID/STAR procedures have to pass stringent environmental assessment.
What CM said.
It’s fun looking up at the dirty belly of an A380 500’ above while tootling along in V1.
It’s fun looking up at the dirty belly of an A380 500’ above while tootling along in V1.
Wake turbulence doesn’t affect an aircraft that is below the aircraft creating the wake turbulence. The clue is in the word “wake”.
I’d certainly be orbiting for a while at a distance if there was a chance of passing through the wake of wide bodied jet.
I’d certainly be orbiting for a while at a distance if there was a chance of passing through the wake of wide bodied jet.
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That is not at all correct, as this crew discovered.Also see: https://www.flightsafetyaustralia.co...ke-turbulence/
"What makes wake vortexes particularly dangerous is that they can persist some distance behind, and below, the aircraft generating them. En route, an aircraft’s wake can extend for more than 25 nm, and descend very slowly downwards and outwards—levelling off around 1000 ft below the generating aircraft.This means encounters can occur when an aircraft passes below the flight path of another aircraft—even though ATC vertical separation is being applied."
Last edited by 4forward8back; 18th Oct 2018 at 23:31. Reason: Added to quote from reference
Are you sure about that?! That is not at all correct, as this crew discovered.
Also see: https://www.flightsafetyaustralia.co...ke-turbulence/
"What makes wake vortexes particularly dangerous is that they can persist some distance behind, and below, the aircraft generating them. En route, an aircraft’s wake can extend for more than 25 nm, and descend very slowly downwards and outwards—levelling off around 1000 ft below the generating aircraft.This means encounters can occur when an aircraft passes below the flight path of another aircraft—even though ATC vertical separation is being applied."
That is not at all correct, as this crew discovered.Also see: https://www.flightsafetyaustralia.co...ke-turbulence/
"What makes wake vortexes particularly dangerous is that they can persist some distance behind, and below, the aircraft generating them. En route, an aircraft’s wake can extend for more than 25 nm, and descend very slowly downwards and outwards—levelling off around 1000 ft below the generating aircraft.This means encounters can occur when an aircraft passes below the flight path of another aircraft—even though ATC vertical separation is being applied."
Of course a big flying thing creates wake turbulence that propagates and persists in all kinds of - sometimes unexpected - directions, including more than 500’ below it. It’s just that at the moment in time the big flying thing is 500’ above another aircraft, the big flying thing is not creating turbulence that will affect the aircraft 500’ below at that point in time. And if the aircraft have tracks that are approximately at right angles, the aircraft below will be a long way away when the turbulence from the aircraft above ‘washes through’ the airspace where the aircraft below used to be but is no longer.
