i was doing a apprroach into YSSY.. and it told em to land at 30L and i clicked ILS Z.. but when i clicked the approach switch it ddidnt have glideslope... so i am wondering if it has to do with ILS z & Y.. cause i was at the right altidude etc... can someone explain to me what is the differenc ebetween ILS Z OR Y ? thanks

Found this:

 

"8.5.1.3.2 The single letter suffix shall be used as follows: 

a) when two or more navigation aids of the same type are used to support different approaches to the same runway; 

b) when two or more missed approaches are associated with a common approach, each approach shall be identified by a single letter suffix; 

c) if different approach procedures using the same radio navigation type are provided for different aircraft categories; and 

d) if two or more arrivals are used to a common approach and are published on different charts, each approach shall be identified by a single letter suffix. If additional radio navigation aids are required for the arrival, they 
shall be specified on the chart’s plan view. For example: 

ILS Z RWY 20 (“DNA VOR Arrival” shown in the plan view) 
ILS Y RWY 20 (“CAB VOR Arrival” shown in the plan view)"

 

 

 

I'm sure some others here can elaborate further.

You hit it on the head.

 

Two ILS approchaes to the same runway, but with differences.

 

Why Z, X, etc..? To help prevent confusion with SID/STAR that are ABC1A, etc..

 

Best regards,

Robin.

Oh okay I understand.

I don't have your charts with me, but have a look at the missed approach procedure.

It could be different depending on what letter (Y/Z) you will have to fly

got yah! thank guys.. thanks once again robin.. when I can help you??? lol....

Look closely at the plates at "NAVAID RQ":

 

the 34L ILS-Z requires the ISN DME

the 34L ILS-Y requires the SY DME

 

(top right hand corner of the plate)

Notice that many X Y Z approaches have different minimums as well.

Can I ignore this?  I only ever have one missed approach: nose first into the nearest piece of tarmac.

Can I ignore this?  I only ever have one missed approach: nose first into the nearest piece of tarmac.

 

If you fly offline you can do what ever you want. Flying online however is a different story....

 

The Y uses an RNAV TAA to join the procedure and requires GPS. The Z uses conventional ground navaids to join the procedure and requires either DME or radar. The two procedures can't be charted on the same chart because the Z has an MSA defined whereas the Y does not.