One of the world’s largest airlines is set to undertake a major technology upgrade, which will see its online reservation system go offline during the early hours of Wednesday, February 4. For United Airlines, it is now urging passengers to monitor their flight details and check in via the carrier’s website or app on Tuesday to avoid any problems that may arise.

Between the hours of 2:30 am and 6:00 am EDT, Chicago-based United Airlines will go offline for its online reservation system to allow the technology upgrade, which will freeze many of its web and app services, including those for both the general public and those who work for the carrier.

United Goes Offline

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United plans to upgrade its flight reservation system, Shares, which will see the airline transfer data from its data centre in North Carolina, through to its high-tech facility in Chicago, as part of a movement where the carrier is gradually transitioning its workforce to cloud-based AWS (Amazon Web Services).

These changes are according to the airline to improve its reliability, and as such, the UA flight schedule will be offline during the early hours of Wednesday, meaning that not only will customers be unable to book flights, but also be restricted from cancelling or amending bookings, checking in for upcoming travel, or even viewing their manage my booking.

This system refresh has been in the pipeline for some time, and as such, the airline has taken proactive measures to help minimise wider disruption, including the cancellation of 600 scheduled flights, and communicating to scheduled passengers over these affected dates that system access will be restricted.

Be Back Online Soon

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According to a report by CBS News, United Airlines has been rehearsing the upcoming data migration process to ensure all involved are aware of expectations, and to minimise any potential disruption to the United States largest airline by fleet size (over 1,000 mainline aircraft). Once the migration process is complete, travelers can expect schedules and the ability to book, cancel, or amend travel like they could before.

International flights and red-eye departures are expected to operate without disruption, as part of the airline’s proactive measures. The 600 cancelled domestic flights will see the majority of morning departures be moved to around 8:40 am EDT, as this allowed the airline to upgrade its reservation system with the right conditions.

The system, Shares, is currently the airline’s mainframe reservation system, which was inherited by United through its merger with Continental in 2012.

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Could This Cause Delays?

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As already mentioned, the airline has taken proactive measures to try and limit any major disruption to travel, and has rehearsed the migration process to try and iron out any concerns that could arise. However, that said, it doesn’t mean that things won’t go as planned, which, if the upgrade suffers any catastrophic failures, could see flight cancellations or delays that could drag on for days until the updated system is fully operational.

United Airlines, which is based in Chicago, operates an extensive network of domestic and international flights to and from the United States. It was a founding member of the Star Alliance, and operates hubs in Chicago, Denver, Guam, Houston, Los Angeles, Newark, San Francisco, and Washington Dulles. The airline was founded in 1926 as Varney Air Lines in Boise, Idaho, and today operates a fleet of more than 1,000 mainline aircraft. Fleet details below as per ch-aviation:

Operating across multiple time zones, the airline is expecting that, in large part, remaining flight operations will not be affected, with the majority of all international and red-eye flights to operate as normal. Codeshare flights will also be unaffected, as these remain operated by other carriers.