Time to start a FAQ for this topic as there have been couple of questions about this the last few days.

There are often times you want to find out whether a specific booking class/seat on a particular flight is available. [Such as whether H is available for sale since you need that for a possible upgrade. Or whether C is available because you need that to be available in order to confirm your upgrade.]

So how do you find out?

The easiest place to do it is at:

www.seatmap.com [A site set up by a Flyertalk]

There are 3 options on this site:

• View Seatmap
• View Galileo Data
• View Etour Data

View Seatmap:

This option will show you the seatmap of the flight you entered. You need to enter all the boxes in order for the seatmap to come up.

So for example, if you want to check AC123 YYZ-YEG in Economy class, you will enter:

Date
Airline: AC
Flight number: 123
Class: Y for Economy, J for Business
From: YYZ
To: YEG

If you fill in any of the above info wrong, it will tell you that the seatmap is not available.

Note that this option is not always accurate given that it will always show some seats as occupied even though it's not (Such as the premium seating section on AC and the first row in J on some aircrafts).

For a more accurate option, you should go to:

http://flyaow.com/classamex.htm

Pick your flights, go all the way to the fare quote page and click on the 'Select a seat' button.

View Galileo Data

This option will show you what booking classes are available for flights between a city pair that you specified.

For example, if you want to find out info about flights between YVR and HKG, you will enter:

Date
Airline: AC [Optional, if you leave it blank, it will show you all airlines]
Flight number: [No need to fill]
Class: [No need to fill]
From: YVR
To: HKG

You will see something like:

YVR HKG 1215#1640 AC 7 J6 C0 Y9 M9 T1 U1 B9 H9 V9 Q9#343*

The meaning of that:

Letter is the booking class. The number after the booking classes denotes the number of seats that AC is willing to sell in that particular booking class. (It only shows up to 9 for AC flights)

Y is the 'main/controlling' inventory and the other booking classes are just a subset of it. If you see Y5M3B3, it doesn't mean there are 11 seats left on the flight for sell. (In this case, it means there are 5 more for sale and AC is willing to sell 3 of those in B and M class, if a B class is sold, it will go down to Y4M2B2.) Same logic for J/C (J is the controlling inventory for business class).

Note: For city pairs that have lots of flights per day, you will need to leave out the 'airline' field in order to get majority of the flights to show up.

View Etour data

This does pretty much the same as the 'View Galileo Data' option. The only exception is that it shows you more booking classes (such as the new domestic fares booking classes).