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717tech
1st Feb 2018, 09:43
Interesting email today from the AFAP regarding Essendon RWY26/08.

It mentions that the strip must be at least 300M wide for Precision/ Non Precision Approaches. Due to the DFO and other structures, it’s only 230M.

My question is who’s responsible? Which of the many strict liability offences are we committing by accepting an ILS onto 26?

Capn Bloggs
1st Feb 2018, 10:55
So what action would the AFAP suggest their members take, now that the AFAP has told us all and we can't plead ignorance if sprung by CASA?

josephfeatherweight
1st Feb 2018, 10:59
Bloggs - reasonable point. I'll go with - "Well, the Regulator knows about it, and hasn't done anything about it, therefore they must deem it safe!"

Transition Layer
1st Feb 2018, 12:05
The whole thing is probably an elaborate (and deliberate) plot to close down Essendon once and for all

fujii
1st Feb 2018, 17:17
ERSA says it’s 300.

717tech
1st Feb 2018, 18:12
ERSA says it’s 300.

I believe that’s the issue. ERSA is supposedly incorrect and there’s no NOTAM.

fujii
1st Feb 2018, 18:33
If that’s the case, it’s been wrong for 12 1/2 years or longer if you include construction time.

Falling Leaf
1st Feb 2018, 20:36
Don't worry, CASA will just construct a 'safety case' and issue a waiver as everyone know's that the horse has well and truly bolted on this one.

Money talks - and the greed, back slapping and dodgy deals that allowed an aerodrome to be converted into a commercial retail district would make a great article.

gordonfvckingramsay
1st Feb 2018, 21:10
Sufficient evidence that it’s safe to continue operations as there have been no accidents despite being too narrow, standby for a rule change. Very clever use of flight testing using revenue flights?

thunderbird five
1st Feb 2018, 21:43
https://www.casa.gov.au/files/vic171120pdf

Capn Bloggs
1st Feb 2018, 22:58
Don't worry, CASA will just construct a 'safety case' and issue a waiver as everyone know's that the horse has well and truly bolted on this one.

Money talks - and the greed, back slapping and dodgy deals that allowed an aerodrome to be converted into a commercial retail district would make a great article.
From the RAPAC minutes, it looks like it was compliant until 2014 when the rules changed. Would you suggest knocking down the DFO or moving the airport?

It would have been better if the AFAP had also published CASA's response to the issue. In other words, the whole thing appears to be a non-issue, although CASA could make the text in ERSA a little clearer: "bl@@dy big buildings just inside the RWS on southern side" as opposed to myriad obstacle notes (one of which has got a bearing digit missing).

alphacentauri
2nd Feb 2018, 02:32
Are you assuming that the position of the gable markers indicate the runway strip? I think you'll find this is incorrect.


According the current MOS 139 gable markers are placed to indicate the limit of the graded portion of the runway strip (MOS 8.2.2). If you read the section on runway strip widths you will find that it is possible to declare a runway strip beyond where the gable markers are placed. Is that not the situation here?


It also goes on to describe the fly over area and how close to the centreline objects within the strip can be placed. It actually says that objects can be within the strip if certain parameters are met. Some interesting things regarding transverse slope.


Without knowing how the areas beyond the graded strip are set up it seems like the strip is compliant and the AFAP could be mistaken. Unless I have misread MOS 139.


Alpha

Lead Balloon
2nd Feb 2018, 02:43
So it’s possible for aircraft (and other things) to be outside the gable markers at an aerodrome but still on the runway?

alphacentauri
2nd Feb 2018, 04:32
According to the wording in MOS 139. Yes.

Im not sure they are considered to be still on the runway. Only considered to be within the strip. The wording explains that when the runway is in use the graded area must be free of obstruction, and that's where the gable markers are.

Lead Balloon
2nd Feb 2018, 04:45
Hmmm. The point of having part of the runway strip outside the gable markers is not obvious to me, if aircraft and other obstacles can be there while the runway is in use.

Fieldmouse
2nd Feb 2018, 05:22
Lead Balloon
Mos 139 6.4 relates to holding points and in particular distance from centreline. This is where the 90m and 150 m graded strips largely come in. Precision approach runway holding points are even further back from centreline at a descending scale along the runway depending on elevation of the holding point in relation to the threshold.
Aircraft at a holding point, usually in line with the gables, are considered to be clear of the runway. But the holding point is often not coincident with the gables.
The 300m runway strip does not relate to ground markings or gables and I have never seen one marked, although it may happen. It is a distance off centreline for the surveyor to reference, not aircraft.

alphacentauri
2nd Feb 2018, 05:28
LB, we share the same sentiments.

Lead Balloon
2nd Feb 2018, 08:49
<snip>
The 300m runway strip does not relate to ground markings or gables and I have never seen one marked, although it may happen. It is a distance off centreline for the surveyor to reference, not aircraft.But what is the reason for “the 300m runway strip” “for the surveyor to reference”? What isn’t allowed to happen inside the 300m runway strip? What’s the point of its existence? :confused:

Traffic_Is_Er_Was
2nd Feb 2018, 09:47
The section outside the graded portion, but within the designated RWS width is known as the flyover. It must be kept clear of fixed objects that project through a plane that starts at the edge of the graded area (the gable line) and extends upwards at 5%. It's purpose is not for the wayward ground movement of aircraft (that's what the graded part is for), but for protection of very low altitude manoeuvring adjacent to the RWY. For a Precision I, II, or III Runway with code number 3 or 4E only the area within 60m of the RWY centre line needs to be kept clear of mobile objects. The gable line is usually used as the reference, but this is actually outside this line. You can have transitory obstacles - vehicles etc - within the RWS as long as they are outside the 60m. As I said, mostly the gable line is used as this is easier.
There is an escape clause for the AD operator who cannot meet the RWS requirements. MOS139 Section 6.2.18.4 refers.

Lead Balloon
2nd Feb 2018, 10:03
Thanks TIEW. That makes sense. I’ve learned something. :ok:

Traffic_Is_Er_Was
2nd Feb 2018, 11:15
No probs. Most of this Surface and OLS stuff harks back to the performance eras of DC-3's etc. I think also that 60m is used rather than 75 (where the gables are) because Australia once used 120m wide Runway strips in the dim dark past, rather than 150, so most taxiways and holding points were designed that way, then we standardised to 150, and it was impractical/impossible to physically comply.

TWOTBAGS
2nd Feb 2018, 21:50
Good on you AFAP ! Highlighting a safety issue 3 years after the event with full knowledge that it has absolutely no bearing on safety what so ever!

Sharp edge of the wedge there boys!

Ever thought about asking the operator if they had the appropriate exemption.....

Before anyone says anything about the King Air V DFO..... by their own documents AFAP acknowledges its not an issue.

Im so glad my AFAP membership dues are being used in this manner it makes me feel so well regarded.

Seriously, which muppet in the the executive thought this was an appropriate allocation of resources.

Once again the AFAP is showing how it is becoming less and less relevant and in touch with its members.:D