VOR v's ILS

[NOTAM]

Just a quick question out of curiosity. Been noticing lately that most high capacity RPT operators tend to go for/are given VOR approaches over ILS's, unless the conditions are extremely marginal. Can anyone shed some light on why this is so? Would have thought that the ILS would be chosen as much as possible for recency. Cheers :ok:

NOTAM.

[Ratshit]

Can't say that agrees with my experience!

Maybe cause the VOR APPR is favoured by the prevailing wind?

R:cool:

[jetstar1]

Where are we talking and when?

[NOTAM]

At Perth Rwy 21 and 24. Both have VOR and ILS approaches, but have noticed a few times that arriving jets have been given the VOR especially when its not very busy.

[No Further Requirements]

ILS off for testing/maint maybe?

Cheers,

NFR.

[jarjar]

Notam, read the notams, 9 out of 10 times the ILS on both runways is off due maintenance, or false GS indications etc etc.

[NOTAM]

Jarjar mate,

On all occasions all ILS' were operational. I know because at the time I was doing the ILS!
P.S. 9/10 times a bit over the top. I fly in and out of Perth 5-6 times a week, 95% of the time there is nothing wrong with the ILS!

[RaTa]

Could be the boys are having a practice at a non precision approach, I've heard Virgin do this a few times.

[jarjar]

NOTAM, I also fly out of Perth 5-6 times aweek, my profile is alittle out of date. The ILS,s have been working well of late. But once or twice a week I see a notam with an ILS out for maintenance(the 9/10 times i refered to is the false indications, when they actually give a reason for unserviceability).
Previous posters may be correct, VOR,s for practice, or no need for a full ILS due to cloud height etc etc.

For whatever reason, its the crew on the day, ATC, ambient conditions, and navaid serviceability that determine the approach.

[Monopole]

Here is a thought,

Most Jet traffic is from the EAST and would more then likely have gotton the old Jenna 4 (RNAV Star), which use to have a visual procedure or arcing for the 21 ILS if IMC.

Now we have a Jenna 5 with tracking to HAIGH for the 21 ILS via WOORA and SNOOK. Much better idea in my opinion :ok:.

Track miles from SNOOK to Touch is 34 NM
Track miles from SNOOK to Touch via the 9 DME arc for the 21 VOR (assuming you join before the IAF for the arc which is roughly PRL is 35 NM

But if you managed to get a Radar Vector from SNOOK to the Straight-in IAF for the 21 VOR you would save yourself 6 NM of 'ARC', and the track NM from SNOOK to Touch is now closer to 31 NM, a saving of 3NM. No biggie for me, but for a Boeing or Airbus maybe.

I'm only taking a 'stab in the dark here. If anyone is curious enough about my maths, could you please check it out on your FMS next time you fly into PHH and let me know how I went.

Cheers

Mono :ok: :ok: