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high-flyer
19th Jun 2007, 09:20
Does anyone know if there's a way to get the 'bus to carry out an orbit in present position if requested by ATC? Currently do it in HDG.

thanks

high-flyer

TopBunk
19th Jun 2007, 09:30
Not on the 'bus any more, but still have manuals which suggest to do it via lateral revision at PPOS.

I guess you Line Select 1L and that should bring up an Option to 'Hold' at 3L? I guess that you would then set the leg distance to 0, to force an orbit.

Should work, failing that do as you say and go into heading and whiz round the heading bug - saves going head down and is quicker;)

Down Three Greens
19th Jun 2007, 09:56
Line 1L as mentioned above.....>HOLD......*INSERT then immediate exit just before halfway around. The aircraft will continue inbound to the fix you had when you started the hold. i.e. the position you activated the hold.
DTG

high-flyer
20th Jun 2007, 07:16
Thank guys, I feel there will be an airbus doing an orbit on the way in Malaga tomorrow afternoon!

high-flyer

earnest
20th Jun 2007, 08:41
KISS.

If you’re already in heading mode:

1. Note your current heading
2. Put fingers on heading knob
3. Turn heading knob in the direction you wish to orbit (clockwise for right hand orbit, anti-clockwise for left)
4. When selected heading has turned through 360 degrees and is back on your original heading, remove fingers from heading knob
5. Return to crossword

:ok:

Advantages

1. It’s quicker
2. Pilot stays heads-up
3. No typing involved
4. No chance of b***erring up FMGC

Disadvantages:

1. Can’t think of any.

wobble2plank
20th Jun 2007, 09:27
Earnest,

Watch out, you're in danger of applying common sense and manual flying techniques in the electric jet!

Don't let the SOP gurus find out ;)

DesiPilot
20th Jun 2007, 16:51
Earnest,

One disadvantage I can think of is if one orbit becomes 2, 3 or even 4 and ATC is not willing to give holding instructions. At least it happens in my part of the world, try flying in to BOM or DEL and you will find yourself orbiting a few times.

So hold with distance 0 works wonders !!

A330AV8R
21st Jun 2007, 03:03
Not on the 320 anymore , but as far as I can remember you hit 1L key go to hold enter reduce the time to 0 mins that should give you a nice circle either L or R to hold at ppos . . . . ooh ya and if your in Hdg you press to manage and voila . . . . . .

hope that helps but I guess you already know that by now :ok:miss flying the little bugger ....

Goliath Bus

Capn Bloggs
21st Jun 2007, 10:15
The advantage of using the FMS to do the orbit is obvious if you have a strong wind. Try doing an "orbit" using the heading bug with a 100kt crosswind blowing. You will end up at least 10nm downwind of where you started. Do another, and guess what?

The FMS will draw a symmetrical circle magenta line and adjust bank angle to make that circle, ending up where you started (well it does in my 717, which is the same FMS [visually at least] as the scarebus).

TopBunk
21st Jun 2007, 11:41
But surely, if asked to 'orbit' there is no requirement to return to where you started out from?

If you are asked to 'take up the hold in your present position' that is another matter all together.

In my view an orbit merely consists of a 360 degree turn to the left or right and to roll out again on the entry heading. Clearly however if you are orbiting on final approach it is desirable to end up back on the centreline;)

earnest
21st Jun 2007, 11:59
Apologies for my seemingly flippant reply. DesiPilot and Capn bloggs make 2 valid points which I entirely agree with. In mitigation, though, I was simply responding to the original question which stated “an orbit in present position”. I took ”an orbit” to mean one orbit, rather like Top Bunk described, not the ad hoc multiple circling pattern in abnormal medium to low level wind conditions which have suddenly been added to the scenario.

Of course, if you are asked to orbit in your “present position” and you initially choose the FMGC method of tactical steering, by the time you’ve done your typing you are no longer in that "present position", whereas if you whirl the heading knob, you more or less are. But that's perhaps being a bit pedantic.

DesiPilot
21st Jun 2007, 18:20
Earnest,

I completely agree with you about the PP.

If you ever fly in Delhi or Mumbai, you'd know from experience that usually one orbit becomes a few and RT can be so busy that you cant get word across to the ATC requesting holding. Now add Monsoon weather to it and you have your hands full. This is the reason I prefer FMGS to keep my hands free so that I can work the Wx Radar, hold my tea while we are being bounced around and try to get a word across to ATC when I can.

Happy landings :)