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GearDown&Locked
27th Nov 2007, 16:01
Qantas B744 Goes Around (http://www.airliners.net/open.file/1298596/L/)

According to the photographer:
Qantas 747-400 (VH-OEI) is seen going around, climbing past us in the A319. We were performing a parallel ("side-by") approach to Runway 28 in San Francisco (SFO) when apparently the heavy couldn't stay behind us and had to go around. It was the most spectacular thing I have ever seen from inside an airplane!

Yeah... :eek:

Track Coastal
27th Nov 2007, 16:35
Was in an independant or dependant parrallel situation? If it was independant he went around for another reason (note visual contact with ground and each other so IMC is not an issue).

GearDown&Locked
27th Nov 2007, 16:47
Ignorant question: is TCAS inhibited in this situation?

ScottyDoo
27th Nov 2007, 16:56
TCAS is set to TA Only on a PRM approach (not "inhibited").

Guys, take another look at the photo. See those buildings way down there, at bottom right? What alt do you think they are, a couple of thou? And the Rat still has the gear down?

And look at the convergence angle (number 2 vs. number 3 donk). These two a/c are seemingly seconds from contact.

You don't think this would've been front-page news and a 38 page thread on pprune if it had actually happened?


Two words: Photo. Shop.

Track Coastal
27th Nov 2007, 17:02
No, in an independant situation you'd probably have traffic info (any American cousins elaborate?) so if betty starts to bleat you know why. Anyways you'd be having to call traffic in sight running it tight like that as the Americans do otherwise you'd need 3nm (5568m) separation. Remember he is landing 28L, your landing 28R.

14 out of the top 20 busiest airports in the world are in the USA and they tend to run em' tight.
http://www.aci.aero/cda/aci_common/display/main/aci_content07_c.jsp?zn=aci&cp=1-5-54-57_666_2__

KSFO runways are here:
http://204.108.4.16/d-tpp/0712/00375AD.PDF

ScottyDoo
27th Nov 2007, 17:10
Whatever...

I think the photographer's last name describes what he has his hand on....... :rolleyes:

757manipulator
27th Nov 2007, 17:11
Scotty, I don't think this pic is photo shopped, look at the sun angle, the reflections on the QF fuselage and the shadow cast by the VX 319 winglet.
What I think makes the QF 747 look a lot closer is the lack of any other reference points other than the 319 winglet and leading edge. You will also notice the relative size of winglet in comparison to the entire QF aircraft, which I think on closer inspection shows the limitations of a 2D image, attempting to explain a 3D situation with all the accompanying problems of geometery and relative motion.
See those buildings way down there, at bottom right? What alt do you think they are, a couple of thou? And the Rat still has the gear down?
Scotty, I guess you've never operated into SFO on a misty autumn day? I reckon they are at around 1500-2000' which would make sense if they had to break off the parrallel approach due to being a 220 tonnes or so and hence having a much faster Vref..in comparison to a 50 tonne 319.

Track Coastal
27th Nov 2007, 17:11
I've no idea what you're getting at. QF has initiated a MAP and hasn't retracted his gear yet and is probably accelerating thru 180KIAS. The bus is waffling down final at 170-160KIAS - no collision risk exists. Fly into any US airport like Dallas or Atlanta you see lots very close on final approach from the window. (I'm ATC not a pilot).

NB EGLL tends to land on one and depart the other on the few times I've been there so looking out out the window and seeing another on final next to you is probably rare.

con-pilot
27th Nov 2007, 17:14
No, the picture is not a photo-shopped picture. During very good VMC approaches the aircraft are very close to each other while doing visual approaches at KSFO. The camera makes the 747 look a lot closed that it is in reality. For proof look at the other pictures at the bottom of the page of the linked picture.

As for why the 747 made a go-a-round is anybodies guess, however, not because of the lateral distance from the aircraft that the picture was taken from.

I have operated in and out of KSFO a lot through the years. Once you have visual contact with the aircraft landing on the parallel runway the tower expects you to maintain separation. It works very well.

Track Coastal
27th Nov 2007, 17:18
...confirms for the scope dope (me). Have a single malt on me (checks in mail);)

ScottyDoo
27th Nov 2007, 17:34
Okay, judging by the size of the winglet, the shot is zoomed-in. And I guess he could've gone around from a couple of grand - odd but who knows.

But:

28L.....28R

Parallel runways.

How do you explain the difference in headings of the aircraft? The jumbo don't look like it's on the same hdg as the bus. :confused:

757manipulator
27th Nov 2007, 17:43
How do you explain the difference in headings of the aircraft? The jumbo don't look like it's on the same hdg as the bus.

Because Scotty, the bus is ahead of the 747...its a visual illusion, which is also exacerbated by the sweep of the baby bus leading edge.

Track Coastal
27th Nov 2007, 17:45
The nut behind the wheel? QFs climbing at go around power and the other descending on 3degs (320ft/nm) so they won't hit and by the photo they must be close to a 1000 vert BUT one assumes that QFs PF got it all together and followed the published or Approach instructions or as you say...

You don't think this would've been front-page news and a 38 page thread on pprune

ScottyDoo
27th Nov 2007, 17:56
hmmmmmm..... maybe, maybe.... :*

GearDown&Locked
27th Nov 2007, 18:00
another boring question: in these parallel approaches, are those guys are on the same radio freq.?

Track Coastal
27th Nov 2007, 18:06
No mate scroll down to radio freqs and look for PRM (Precision Runway Monitor)...

http://www.airnav.com/airport/KSFO

con-pilot
27th Nov 2007, 18:09
For years there was another airport that you could have two aircraft flying very close together but this was on VMC departures. The airport is KDCA, Washington National Airport, in downtown Washington DC.

http://i28.photobucket.com/albums/c246/con-pilot/00443AD.gif


During southbound operations there would be simultaneous takeoffs on runway 19 and 15. For nose abatement after takeoff engine thrust was to be reduced and all aircraft had to fly down the Potomac River until well south of the airport. Many times I would be taking-off on 15 in a biz-jet just after an airliner passed the 15/19 intersection. All departures from 15 had to turn right and avoid the east side of the river immediately after takeoff, which was rather fun, and then maintain visual separation from the aircraft that departed 19.

Basically what this meant was that you flew in formation with the aircraft that had departed on 19. Then when you clear of the noise sensitive area departure control would clear the aircraft higher and separate them routing wise on radar.

Sometimes this could be very interesting. :ooh:

ScottyDoo
27th Nov 2007, 18:09
In Sydney, it's separate tower freqs for the two parallel runways but aircraft on both monitor 121.5 during PRMs in case of a fark-up and that particular TWR freq is congested.

Might or might not be different APP freqs depending on which direction each guy came in from and local SOPs.



You want interesting, Con-Man? Try Simultaneous Opposite Direction operations. Arr 34L and Dep 16L..... :ok:

Ballsy or stupid - not sure which.

con-pilot
27th Nov 2007, 18:25
You want interesting, Con-Man? Try Simultaneous Opposite Direction operations. Arr 34L and Dep 16L.....

I've done that type of operations probably a thousnand times in Aspen, Colorado, KASE. All aircraft depart on runway 33 and all aircraft land on 15. Head to head operations all the time. Yup, it is very interesting.

http://i28.photobucket.com/albums/c246/con-pilot/05889AD.gif

Track Coastal
27th Nov 2007, 18:33
Reciprocals at Aspen :eek:

American ATC* and its pilots blow me away.:D:D:D

*Having done ATC in that part of the world, the Americans and Canadians are simply the best for getting from A to B without hitting each other and without 19 bibles of regs, bullshit and over control and on runway conditions (ice, slush and snow) that I often used to shake my head in amazement :ok:

BAMRA wake up
27th Nov 2007, 18:34
Similar, but less zoomed photo here of the same approach. Going on the apparent winglet size this one is probably zoomed beyond what the unaided eye would see. Focal length 70mm lens on an old style film slr camera produced a true impression of relative distance of objects.

http://www.airliners.net/open.file/0176899/M/

Track Coastal
27th Nov 2007, 18:52
During very good VMC approaches the aircraft are very close to each other while doing visual approaches at KSFO....

I have operated in and out of KSFO a lot through the years. Once you have visual contact with the aircraft landing on the parallel runway the tower expects you to maintain separation. It works very well
There you have it:D

Aaaaaaaaaaaaaaaargh!
27th Nov 2007, 18:57
Actually

http://www.adobe.com/products/photoshop/images/logos/ps_logo_228x52.gif

is one word not two. :hmm:

con-pilot
27th Nov 2007, 19:17
I stand correctly chastised Aaaaaaaaaaaaaaaargh!. :(











;)

con-pilot
27th Nov 2007, 19:35
Track, the reason for the reciprocal operations at Aspen is due to the most part because of the runway slope. The runway elevation drops 140.1 feet from the south to the north, Runway 33 end is 7,819.9 feet, Runway 15 end is 7,679.8 feet, the runway length is 7,000 feet.

From the airport procedure's manual;

TKOF NOT AUTHORIZED ON RY 15 WITHOUT WRITTEN PERMISSION FM AMGR.

In real life it is better to land with 15 knot tailwind on 15 than land on 33 with a 15 knot headwind. I have landed on 33 a few times and even with a 25 knot headwind it still takes a lot of heavy braking with maximum reverse thrust to get stopped.

There are days that have periods that you just cannot land or takeoff because of the wind. I hate that place and hope to hell I'll never go back.

ScottyDoo
27th Nov 2007, 19:43
Actually

http://www.adobe.com/products/photoshop/images/logos/ps_logo_228x52.gif

is four words, not one.

BlooMoo
27th Nov 2007, 22:08
CP - pls correct me if you may as this is bugging me, my flying exp is overwhelmingly insignificant compared to almost anyone so I'm not trying to be clever - I just assume I have something 'arse about face'. but don't understand why
Runway 33 end is 7,819.9 feet,
i.e Northern end of tarmac is approx 7820' ?
Runway 15 end is 7,679.8 feet
i.e. Southern end of tarmac is approx 7680' ?
Therefore North end is approx 140' higher than South end. ?
runway elevation drops 140.1 feet from the south to the north
Doesn't the runway elevation drop approx 140' from North to South rather than other way around?
i.e. approaching from the North (landing 15) you're landing downhill ?
Sorry, just a straight question on a technical thingy. Suspect I'm confusing 'end' with 'threshold' or 'approach end' or the like
BM:confused:

con-pilot
27th Nov 2007, 22:42
Ah shoot, now I'm confused. Okay, let's put it this way. When you land on 15 the elevation of the runway at the touchdown end is 140 lower than the other end. You land uphill to the south and takeoff downhill to the north.

Sorry for the confusion.

C-P


(The lack of oxygen in Aspen has caused me brain to lose a few cells.)

BlooMoo
28th Nov 2007, 00:01
Con-Pilot - I appreciate your time. My problem as I see it is terminology - I may well have a good night's sleep now. Thank-you.
BM :ok: