Introduction
If you are stepping into the world of travel and aviation, mastering a Global Distribution System (GDS) is non-negotiable. Galileo is one of the most widely used GDS platforms in the industry, powering travel agencies and airlines worldwide. Whether you are an aspiring travel agent, a student, or a professional looking to expand your skill set, understanding Galileo’s core commands is your first step toward proficiency.
In this first lesson of the Galileo for Beginners series—available for streaming right above—you’ll learn the fundamental commands every travel professional needs to search for flights, decode airport and airline codes, check availability, and sell seats. These are the building blocks of airline reservations; commands you will rely on daily.
Why Galileo Matters
Galileo (now part of Travelport) remains a powerhouse in the travel industry. It allows agents to access real-time flight availability, pricing, and booking capabilities across hundreds of airlines. Understanding how to navigate this system efficiently separates a competent agent from an exceptional one. The commands covered in this tutorial are your entry point into that world.
1. Airport Encode & Decode (.CE / .CD)
Before you can book a flight, you need the correct airport and city codes. Galileo provides two essential commands for this:
.CE – City Encode
The .CE command converts a city name into its three-letter IATA airport code.
.CE MUMBAI
Returns: BOM (Chhatrapati Shivaji Maharaj International Airport).
.CD – City Decode
The .CD command does the reverse—it takes a three-letter airport code and returns the full city name alongside specific airport details.
.CD RUH
Returns: The city name for Riyadh, Saudi Arabia.
2. Airline Decode (.AD)
Just as cities have codes, airlines do too. The .AD command decodes an airline code to reveal the full carrier name.
.AD TK
Returns: “Turkish Airlines.”
.AD IB
Returns: “Iberia.”
This command is invaluable when scanning availability displays, allowing you to instantly identify which carrier operates a particular flight.
3. Flight Availability (A)
The A command is the engine room of flight searching in Galileo. It displays available flights between two cities on a specific date.
Basic Availability Format
A<Date><City Pair>
A15DECLONPAR
This shows all available flights from London (LON) to Paris (PAR) on December 15th.
Carrier-Specific Availability
To filter availability for a specific airline, use:
A<Date><City Pair>*<Carrier Code>
A18NOVIXEBOM*9W
Shows only Jet Airways (9W) flights on that route.
Understanding the Availability Display
Once you run the A command, Galileo returns a structured display showing:
- Flight numbers
- Operating airlines
- Departure and arrival times
- Number of stops
- Available booking classes with seat counts (e.g., Y, J, F, M, B, S)
4. Economy, Business & First Class Booking Classes
Booking classes are not just random letters—they represent specific fare rules, restrictions, and pricing tiers.
- Economy Class: Common classes include Y, M, B, S, Q, V, and L. Each has different advance purchase requirements and refund policies.
- Business Class: Common classes include J, C, D, and Z, offering premium seating and flexible rules.
- First Class: Common classes include F, A, and P, representing the highest service level.
When reviewing an availability display, look for these letters next to each flight to see how many seats are up for grabs in each tier.
5. Selling Seats Using the N Command
Once you have found the perfect flight, it is time to sell a seat. The N command (or 0 command in some versions) is used to book seats directly from the availability display.
Basic Sell Command Format
N<Number of Seats><Class of Service><Line Number>
N1Y1
Sells 1 seat in Economy (Y class) from availability line 1.
Selling on Connecting Flights
For connecting flights where the same class is available on both segments:
N<Seats><Class><Line1>*
Example: N1Y1* sells 1 seat in Y class on both segments.
For connecting flights requiring different classes per segment:
N<Seats><Class1><Line1><Class2><Line2>
Example: N1Y1B2 sells 1 seat—Y class on segment 1, B class on segment 2.
Practice Makes Perfect
The commands covered in this lesson may seem simple, but mastery comes through repetition. Watch the embedded video above and practice alongside the instructor. Here is a suggested routine:
- Encode/Decode: Pick 10 random cities. Encode them using
.CE, then decode 10 random airport codes using.CD. - Airline Decode: Choose 10 airline codes and decode them using
.AD. - Availability: Run availability searches for diverse routes and dates using the
Acommand. - Selling: After each search, practice selling seats using the
Ncommand with different booking classes. - Workflow: Build a complete micro-workflow—encode a city, check availability, decode an airline, and sell a seat.
Summary of Commands (Quick Reference)
| Command | Purpose | Example |
|---|---|---|
.CE<City Name> |
Encode city to airport code | .CE MUMBAI |
.CD<Airport Code> |
Decode airport code to city name | .CD RUH |
.AD<Airline Code> |
Decode airline code to airline name | .AD TK |
A<Date><City Pair> |
Check flight availability | A15DECLONPAR |
A<Date><City Pair>*<Carrier> |
Check availability for a specific airline | A15DECLONPAR*BA |
N<Seats><Class><Line> |
Sell seats from availability | N1Y1 |
N<Seats><Class><Line>* |
Sell on connecting flights (same class) | N1Y1* |
N<Seats><Class1><Line1><Class2><Line2> |
Sell on connecting flights (different classes) | N1Y1B2 |
Next Steps
This first lesson lays the foundation for everything that follows in the Galileo for Beginners series. Once you are comfortable with these commands, you will be ready to move on to creating full Passenger Name Records (PNRs), adding passenger details, handling special service requests, and processing ticketing.
Remember: every expert was once a beginner. Watch the video tutorial at the top of this page, practice these commands daily, and you will build the muscle memory needed to work efficiently in Galileo.
Have questions about this lesson? Drop a comment on the video or reach out to the instructor. Happy booking! ✈️
Amadeus Lesson 6: How to price a PNR(FXX, FXP, FXR & FXB)
Amadeus Lesson 5: How to add a Frequent Flyer Card (FFN & SR)


