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9 Nightmares to Avoid During PSS Migrations

Passenger Service Systems (PSS) are among the most complex systems used by airlines for reservation and departure control and are pivotal to airline business operations. Many of these systems traditionally run on mainframes and have either gone through a major upgrade or been scheduled for one. Some of the PSS systems are shared by many airlines making system update/upgrade/migration an involved process riddled with business risks. It’s like attempting a heart transplant surgery on an aged patient on the move!

Changes in business strategy or technology obsolescence are generally the drivers for airlines to move from one PSS to another. It takes several years to plan and move to a new PSS where even minor defects lead to considerable revenue loss and poor customer experience.

In our experience with planning and implementing the PSS for our airline customers, we have noticed several common challenges that are encountered during the migration. It is very helpful to take stock of the challenges faced by others in the industry and preempt them before your next planned migration.


#1 Poor Test Planning and Execution

Comprehensive use case preparation is critical to successful testing in a business system like PSS. Incomplete or poorly planned testing can delay PSS migrations or create debilitating issues after cut-over. If business user scenarios are not completely tested ahead of the final migration/cut-over, there are no guarantees for the system functionality after go-live. For a smooth cut-over, all valid business use cases should be documented as specific scenarios in addition to thorough unit testing. Business users with different designated roles should perform the actual business validation during every planned testing phase. It is crucial that comprehensive business testing is done on the day of the migration before the legacy system is finally brought down for cut-over. We work with the business champions in our customer business groups to discover all the business use cases and prepare for consistent and thorough testing.

#2 Inadequate Dress Rehearsals

It is critical to rehearse the data migration process to ensure that all the right data will be migrated into the new PSS and to immediately establish BAU [Business as usual] for the airlines. In the 1-2 year planning phase ahead of the actual implementation, dress rehearsals are done several times to refine the migration process and achieve close to 98-99% success so that data, process and system related issues are ironed out well in advance. As part of the dress rehearsal, unit testing and end-to-end testing should also be done on the migrated data. Not following this level of rigor can land the customer in a seriously compromising business situation without a way of retracting the changes.

#3 Performance/Load Testing & Monitoring Problems

It is important that complete infrastructure evaluation and stringent load testing are done on the new PSS so that the customer and IT teams are convinced that the new PSS system can handle the expected load on the airline’s website and all downstream systems on Day 1. Performance and monitoring issues can bring the systems down for hours causing customers to incur additional unplanned costs. While frontend may not show any stress due to this, the backend can get irretrievably backed up under severe performance stress. This could also trigger a chain reaction for many airlines if the PSS is shared by all of them. Sporadic and scattered load testing can make things exponentially worse very quickly.


#4 Lack of Training

There was a time when a certain airline was leading the news headlines for all the wrong reasons. On the day of the cut-over, it took so long to process some transactions on the new system that queues snaked all the way out of the airport. The primary reason for this embarrassment was that the airport staff was ill-equipped and inadequately trained to navigate the new PSS.

Why does this happen? How can such a basic step missed? When the PSS is migrated to the new system, many users may have likely spent 20-30 years on the old system and lack appropriate skills and are slow to change. Sometimes, training may have been done far ahead of the D-day on training systems that bear little resemblance to what they face on Day 1.

In order to combat this, technical and business readiness should be a project management activity that should be monitored to successful completion. When the airline employees are anxious and under pressure to service the customers on Day 1, they are prone to act expediently which can end up in a catastrophe. This should be mitigated by early training and multiple refresher trainings till the day of the cutover.

#5 Login Issues

It may be surprising to learn that the most common issue that users experience with PSS migration is the lack of right login access or the right access privileges to perform their function. Typically, users are assigned temporary passwords with secure tokens but, they tend to expire within 24 hours unless they access it and change their password. It is very important for airlines to have logins activated and available before the cutover, and have the employees test their logins before the migration. This is an important and easily avoidable challenge so that business is ready when the PSS is.

#6 Abuse of Overrides

PSS systems generally have a feature called ‘involuntary exchange’ that helps the airline agents swap fare classes or exchange tickets for free and other such process overrides in order to handle situations that cannot be resolved otherwise. However, when the agents abuse the override feature in their anxiety with the new PSS in order to let the flight take off at any cost, their actions can cause significant loss to the airlines. We have seen airlines suffering significant losses due to this. Needless to say, it also causes many issues in revenue accounting processes. Sometimes, it could even cause regulatory non-compliance with weight and balance of the aircraft going out of control.

PLANNING – Day 0 (Migration) and Day 1 (Go Live)

#7 Dormant Applications

Sometimes, there are rule-based applications or processes running in the background in dormant mode, which execute specific pre-defined steps when the rules are satisfied. In one of the PSS migrations, a customer had an application with test rules to cancel duplicate Passenger Name Records (PNR). When the system was restarted after the migration, it so happened that this dormant application became active, which determined that several thousand PNRs from the old and the new systems are duplicate and cancelled them in a matter of minutes. It had to be undone using another automated application after the fact. It is important to manage the development/test/production environments with precision so that such unexpected and costly mistakes won’t happen.

#8 Incorrect Revenue Reporting

In one of the PSS migrations, we found that lack of coordination between the web service and the payment gateways caused duplicate charges/holds for several PNRs were occurring on customer credit cards causing a huge public relations and customer service debacle. This can be avoided by complete business use case validation on the day of the migration so that Day 1 is not a surprise. Airlines also need to identify all critical reports required to make sure that the revenue accounting system is getting all the data correctly and that all transactions are properly accounted. In one case, their taxes were not correctly accounted, which became a major ordeal to fix manually.

#9 Blackout

Blackout is the worst possible scenario. In one of the migrations, we found that a web service handling all the security and authentication got updated that updated the web service credentials in turn. This caused issues for several processes with application access. Though the frontend did not show the issue for some time, the backend got excessively backed up, which eventually brought the entire system down impacting over 60 airlines that use the system. It took over 8 hours to bring back the services after causing losses of millions of dollars.


NIIT Technologies has rich and extensive experience in handling the migration of several  PSS systems over the years and have built strong expertise in airline business domain. We have planned and implemented IT system changes and data migration projects with effective and balanced governance policies.

We can also play a consulting role and act as an effective bridge between the PSS provider and the business teams. We can include all areas including infrastructure consulting, project management consulting and business validation consulting.

Knowing the business challenges ahead of the IT system implementation of this nature can prepare you with all the right tools and processes to mitigate those very challenges.

NIIT Technologies has worked with several airline companies in migrating PSS and can work with you and help you leapfrog these very challenges.

Partner with us today for your PSS migration.

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