kearnet
Topic Author
Posts: 217
Joined: Thu Sep 13, 2001 11:56 am

Yssy - Txy T1 East Of Txy U, What's Its Purpose?

Sat Jul 02, 2011 1:28 am

So while browsing over YSSY (SYD) on Google Maps last night, I noticed Taxiway T1 east of Taxiway U is essentially a big fillet to bring aircraft off 16L, which would be fine except the touch down point is just beyond where it meets the Rwy, not to mention I don't know of any aircraft that could land that short anyway and yet require a fillet of that size (Same is true with an incredibly-beyond-midfield take off from 34R)

Can anyone explain what it's purpose is?
DC-9-30 US|MD-80 US/AA|737-200 US|737-300 US/WN|737-400 US|737-700 WN|737-800 FJ/QF|F-100 US|F-28 US|Dash-8 200 US| CRJ-200 US|757-200 US/AA|767-200 DL|777-300ER EK|A319-100 US|A320-200 B6|A330-200 FJ|A380-800 EK|ATR-72 AA|B-1900D US
 
ShyFlyer
Posts: 4698
Joined: Fri Jun 19, 2009 11:38 pm

RE: Yssy - Txy T1 East Of Txy U, What's Its Purpose?

Sat Jul 02, 2011 2:05 am

Aerodrome Chart for YSSY, for reference:
http://www.airservicesaustralia.com/...ations/current/dap/SSYAD01-126.pdf

Quoting kearnet (Thread starter):
Can anyone explain what it's purpose is?

My guess would be that it provides a more convenient exit point for aircraft attempting to depart from 16L, such as aborting early in the take-off roll (or even before beginning said roll). Other wise, they'd have to roll all the way down to taxiway T3 before exiting.
I lift things up and put them down.
 
kearnet
Topic Author
Posts: 217
Joined: Thu Sep 13, 2001 11:56 am

RE: Yssy - Txy T1 East Of Txy U, What's Its Purpose?

Sat Jul 02, 2011 4:21 am

Quoting ShyFlyer (Reply 1):
y guess would be that it provides a more convenient exit point for aircraft attempting to depart from 16L, such as aborting early in the take-off roll (or even before beginning said roll). Other wise, they'd have to roll all the way down to taxiway T3 before exiting.

Perhaps, but how often does that happen that'd require a purpose built taxiway? If you needed one for such reasons, wouldn't placing it 1/4 to 1/3 down be more realistic - sort of a compramise of distance vs. purpose?
DC-9-30 US|MD-80 US/AA|737-200 US|737-300 US/WN|737-400 US|737-700 WN|737-800 FJ/QF|F-100 US|F-28 US|Dash-8 200 US| CRJ-200 US|757-200 US/AA|767-200 DL|777-300ER EK|A319-100 US|A320-200 B6|A330-200 FJ|A380-800 EK|ATR-72 AA|B-1900D US
 
CplKlinger
Posts: 270
Joined: Sun Oct 03, 2010 3:05 pm

RE: Yssy - Txy T1 East Of Txy U, What's Its Purpose?

Sun Jul 03, 2011 3:12 am

Quoting kearnet (Reply 2):
Quoting ShyFlyer (Reply 1):
y guess would be that it provides a more convenient exit point for aircraft attempting to depart from 16L, such as aborting early in the take-off roll (or even before beginning said roll). Other wise, they'd have to roll all the way down to taxiway T3 before exiting.

Perhaps, but how often does that happen that'd require a purpose built taxiway? If you needed one for such reasons, wouldn't placing it 1/4 to 1/3 down be more realistic - sort of a compramise of distance vs. purpose?

I think the main reason for this is so that a larger aircraft (A380, 747, AN-225 and what have you) would have plenty of space to make the turn off of 16L if they needed to quickly. Part of the planning that goes into layouts is allowing for aircraft to exit quickly if needed such that they don't get stuck in a bad situation or block a runway.

Say, for instance one of Qantas' A380 is on 16L, goes to full power and has an engine surge and decides they need to go back to the gate to get it checked. Without the turn there at T1, they have to go all the way down to T3 or maybe even T4, depending upon their max turn radius to get back to the gate. Since they're going to be up towards MTOW, they're going to be slow because of the weight in turns, which mucks up sequencing in the tower. With T1 there, they zip off the runway and back towards the gate.
 
Gemuser
Posts: 4297
Joined: Mon Nov 24, 2003 12:07 pm

RE: Yssy - Txy T1 East Of Txy U, What's Its Purpose?

Sun Jul 03, 2011 3:18 am

Quoting kearnet (Thread starter):

Can anyone explain what it's purpose is?

I'm guessing, but to me it looks like a less sharp exit for wide bodies from runway 34R. Purely looking at the chart the exit to T1 seems a bit tight and U1 makes the turn easier for WBs.

Gemuser
DC23468910;B72172273373G73873H74374475275376377L77W;A319 320321332333343;BAe146;C402;DHC6;F27;L188;MD80MD85
 
CplKlinger
Posts: 270
Joined: Sun Oct 03, 2010 3:05 pm

RE: Yssy - Txy T1 East Of Txy U, What's Its Purpose?

Sun Jul 03, 2011 6:42 am

Quoting gemuser (Reply 4):
I'm guessing, but to me it looks like a less sharp exit for wide bodies from runway 34R. Purely looking at the chart the exit to T1 seems a bit tight and U1 makes the turn easier for WBs.

Gemuser

OP is discussing the usage of U1 coming from 16L. In the case of 34R, you are completely correct.
 
buckfifty
Posts: 1278
Joined: Tue Oct 16, 2001 4:05 pm

RE: Yssy - Txy T1 East Of Txy U, What's Its Purpose?

Sun Jul 03, 2011 10:26 am

T1 is used primarily for intersection departures, IIRC.
 
Gemuser
Posts: 4297
Joined: Mon Nov 24, 2003 12:07 pm

RE: Yssy - Txy T1 East Of Txy U, What's Its Purpose?

Sun Jul 03, 2011 11:30 am

Quoting CplKlinger (Reply 5):

OP is discussing the usage of U1 coming from 16L. In the case of 34R, you are completely correct.

So??? I agree with you, but why can't U1 be there for 34R only, ie it's of no use for 16L, but is there for 34R?

Gemuser
DC23468910;B72172273373G73873H74374475275376377L77W;A319 320321332333343;BAe146;C402;DHC6;F27;L188;MD80MD85
 
CplKlinger
Posts: 270
Joined: Sun Oct 03, 2010 3:05 pm

RE: Yssy - Txy T1 East Of Txy U, What's Its Purpose?

Sun Jul 03, 2011 1:58 pm

Quoting gemuser (Reply 7):
So??? I agree with you, but why can't U1 be there for 34R only, ie it's of no use for 16L, but is there for 34R?

Gemuser

Because it's not there for 34R:
http://i283.photobucket.com/albums/kk300/bc16665/Capture.jpg

It's clearly there for exiting from 16L. If you're exiting 34R, it makes no sense to try and make the turn for T1 when U1 is right there. Besides, if you extend the curve of T1 around to the runway, it doesn't fit the profile of an exit from 34R.
 
ShyFlyer
Posts: 4698
Joined: Fri Jun 19, 2009 11:38 pm

RE: Yssy - Txy T1 East Of Txy U, What's Its Purpose?

Mon Jul 04, 2011 1:48 am

Quoting CplKlinger (Reply 8):
f you're exiting 34R, it makes no sense to try and make the turn for T1 when U1 is right there.

Further, look at the taxiway centerline. Exiting 34R at T1 is clearly not recommended/allowed or there would be markings for that.
I lift things up and put them down.
 
thegeek
Posts: 1330
Joined: Mon Nov 26, 2007 7:20 am

RE: Yssy - Txy T1 East Of Txy U, What's Its Purpose?

Mon Jul 04, 2011 3:43 am

Quoting CplKlinger (Reply 3):
Say, for instance one of Qantas' A380 is on 16L, goes to full power and has an engine surge and decides they need to go back to the gate to get it checked. Without the turn there at T1, they have to go all the way down to T3 or maybe even T4, depending upon their max turn radius to get back to the gate. Since they're going to be up towards MTOW,

A380s couldn't use 16L near MTOW. I'd be surprised if they could use it all. It's doubtful it is long enough to have a full pax load (no cargo) and enough fuel to reach SIN, or maybe even AKL. So why would the taxiways we up to scratch for the A380?

744 isn't much better. The largest plane which uses 16L/34R in normal service (that I am aware of) is the A330. I've never seen an A333 either, but it doesn't mean it can't happen.
 
CplKlinger
Posts: 270
Joined: Sun Oct 03, 2010 3:05 pm

RE: Yssy - Txy T1 East Of Txy U, What's Its Purpose?

Tue Jul 05, 2011 3:40 am

Quoting thegeek (Reply 10):
A380s couldn't use 16L near MTOW. I'd be surprised if they could use it all. It's doubtful it is long enough to have a full pax load (no cargo) and enough fuel to reach SIN, or maybe even AKL. So why would the taxiways we up to scratch for the A380?

744 isn't much better. The largest plane which uses 16L/34R in normal service (that I am aware of) is the A330. I've never seen an A333 either, but it doesn't mean it can't happen.

I was using "for instance" to mean a general example. I just used the first type that popped in my head. I know that they won't use this runway, I was just using an example. Any aircraft, short of GA types would not be making the turn I described.
 
User avatar
cpd
Posts: 4549
Joined: Sat Jun 28, 2008 4:46 am

RE: Yssy - Txy T1 East Of Txy U, What's Its Purpose?

Sat Jul 09, 2011 10:46 am

Quoting CplKlinger (Reply 3):

I think the main reason for this is so that a larger aircraft (A380, 747, AN-225 and what have you) would have plenty of space to make the turn off of 16L if they needed to quickly.

B747 can use 16L, but AN-225/AN-124 and A380 would never use that runway. And I suspect, B747-8i wouldn't use it either.


If I'm not mistaken, A380 is forbidden to use that runway.
 
CplKlinger
Posts: 270
Joined: Sun Oct 03, 2010 3:05 pm

RE: Yssy - Txy T1 East Of Txy U, What's Its Purpose?

Tue Jul 12, 2011 3:03 am

Quoting cpd (Reply 12):
B747 can use 16L, but AN-225/AN-124 and A380 would never use that runway. And I suspect, B747-8i wouldn't use it either.


If I'm not mistaken, A380 is forbidden to use that runway.

I know this, as I said here:

Quoting cpd (Reply 12):

I was using "for instance" to mean a general example. I just used the first type that popped in my head. I know that they won't use this runway, I was just using an example. Any aircraft, short of GA types would not be making the turn I described.

I was just making an example. Using the first things that popped in my head. When I think big I just happened to think VERY big.

Who is online

Users browsing this forum: No registered users and 15 guests