why inbound course on the 320
 

hello,

I am TRE on the 320.

one of my students asked me why on the bus, the holding pattern use "inbound course"in the FMCG when holding course are based on a OUTbound leg.


I can not answer!!!!!.

You hold on a radial which is a course out of a navaid. You navigate on the reciprocal course to track inbound. You don't track outbound once established in the hold.

i know we track the inbound, but controller give outbound like" hold on the 360 radial", mean the FMCG must have the 180 in his system.

my students always have to calculate opposite radial, and some do mistakes when the punch numbers in the FMCG...

so what's the best to calculate fast?, with no calculator.

If you were selecting a navaid to hold at a VOR you would also set the inbound course so the FMGC is not doing anything out of the usual.

For a gross error check go to rose nav and check the opposite of what you have been given.

To be brutally honest if you cannot add/subtract 180 to a number you are probably in the wrong job. God forbid what they would get upto if they had to do manual holds with a crosswind!!

Add 200 subtract 20 or subtract 200 add 20 is pretty simple.

And switch your ND to Rose NAV and double check that your maths was correct.

A320Rider:
The Bus FMS is correct. You always hold inbound on-course.

For unplanned (i.e., uncharted) holding the controller is supposed to give you one of eight cardinal compass and the holding course, such as a radial, airway, NDB bearing, etc. If the direction of turns is omitted then it's right turns.

Example, hold at ABC VOR, southeast, on the 135 radial. The holding fix is the VOR, the inbound holding course is 315, and right turns are made.

Eample, hold at ACMEE Intersection, west on Victor 999, left turns. Say that V-999 is the 260 radial of ABC VOR at 25 miles. The holding course is 080 inbound on V-999, with the DME counting down to 25 arriving at the holding fix.

It has always been a confusing subject for pilots that haven't been drilled in the subject. A common mistake is to mistake the direction of holding issued by the controller as the direction of the turns; i.e. left or right.

A320rider
Don't worry - it's an age thing.....

Thread hijack...
 

Aterpster,
Please explain.

You are probably correct Mr Roberts, but I'd rather hear for pattern D :
Hold northeast of the 10 DME fix ABC VOR 220 degree radial, left turn.
Small difference but easier to figure out ... at least for me.

Aterpster,

If the instruction was like this (from our AIP):

HOLD AT (way‐point, facility or fix) (callsign and frequency, if necessary) (level)
INBOUND TRACK (three digits) DEGREES
RIGHT (or LEFT) HAND PATTERN,
OUT‐BOUND TIME (number) MINUTES
(additional instructions, if necessary)

then no such confusion would result.

In addition, the format of this instruction also helps A320Rider with his FMS inputs. Probably why our AIP says it that way...

Moving mountains is easier than getting FAA's Air Traffic Organization to change its way.

If some other country uses more clarity, so much the better.

I wrote that article for domestic USA operations.

My experience has been that the more you talk or think about holding, the more confused you get.

It took me 8-10 years of flying to be able to do it in my head, and now that I have it down, I don't want to hear any more about it.

At some point the light goes on, you immediately visualize the pattern when the clearance is given, and you feel threatened by any further discussion of the process.

All you need to know on the Airbus FMS is the holding fix inbound course, direction of turns, and length or time of legs. The ND will paint the picture, you make sure you're in managed NAV, and everyone's happy. If the pattern is in the data base, all the better.

Don't even think about it.

BenThere:
If the pattern is in the database the problem is solved.

Maybe the reason you can not answer is due to the fact you are not a TRE.

Mega quick way to work out reciprocals

Using the first 2 digits, take 2 from digit 1, and add to digit 2, or vice versa.
eg

Heading 035 becomes 215

Heading 218 becomes 038

Heading 149 becomes 329

Doesn't always work as your answer may take you above 360, however easy to correct if it does.

That concludes our lesson for today. Happy flying to all you cloud bunnies

That was my first thought. Anybody who can't figure out a reciprocal and doesn't know holds are not based on the outbound leg probably doesn't even have an instrument rating much less a 320 TRE qualification.

Why not just ask the question without misrepresenting yourself?