Originally Posted by
etudiant
If memory serves, the airline IT systems were cooperatively developed/shared among carriers, which might help explain the below normal percentage of revenue invested.
This is partly true as three of the big four global distribution systems (GDSs) - Worldspan, Galilieo and Amadeus - were set up by airlines. In contrast, Sabre was built by American Airlines and IBM. Then there is BA which had its own British Airways Booking System (BABS), a development of BOAC's booking system launched in the late 1960s, which ran up to 2002 until the switch to Amadeus.
So, some airlines gained from shared development and running costs, but it looks unlikely to me that this would account for the IT underspend compared with other industries.