Low-budget airline Ryanair has ripped out and replaced key parts of its new booking system after IT problems prevented it from taking some bookings efficiently and complying with a competition ruling.

The technical glitch had prevented the budget airline from complying with rules on price transparency set by the Office of Fair Trading (OFT) that require all fixed non-optional costs, such as taxes, to appear.

This is the third problem the airline has experienced since switching on the Navitaire New Skies system in February, and prompted suggestions the company should conduct thorough load testing on its site and act to avoid similar problems in the future.

Earlier this month, Howard Miller, chief financial officer at the airline said the system upgrade had been vital to ensure Ryanair could cope with growing website traffic, despite the problems experienced after go-live.

Two key pricing systems caused the new problem, which emerged in the last fortnight, a spokesperson at Ryanair said. The first was a struggling system that shows full pricing including taxes and charges throughout the booking, and the second a module that shows available prices throughout the week on one display.

The company ripped out both elements, and has replaced the tax display module in the last two days, it said. It is currently working with supplier Navitaire to replace the other module. A message on the Ryanair website advises customers that bookings and confirmation emails may be “slow” and that it could take up to a minute to switch between pages on the website.

The removal of the tax display prompted media reports that Ryanair was attempting to hide true prices from customers. It had been forced to upgrade to the New Skies system and show the full prices in order to comply with the OFT ruling made last year.

A spokesperson for Ryanair rebutted the stories, saying they were “pure silliness” and that the removal of the taxes display was to make the IT systems work. “We had to take out the modules as booking was being blocked. We’ve made a big effort with Navitaire, who are constantly working on the issue.”

“It’s peak season and there’s high traffic, but with or without the traffic the system was slowing down,” he added.

Previous problems with the website prompted some analysts to speculate that better testing was needed, because Ryanair conducts nearly all its business through its website.

Speaking on the new problem, David Chalmers, director of product planning at software testing firm Macro 4, said: “It’s tempting for firms to do straightforward tests on individual pieces of software. But they need to do real stress testing and use the tools to simulate large numbers of users going through the whole booking process.”

He continued: “The more difficult problem is when things are moving but going more slowly. You need to find and fix exactly which parts are going wrong, and use application index software to examine cases when customers are experiencing problems, even if the majority of customers are going through the process smoothly.”

Robin Goad, analyst at competitive intelligence website Hitwise UK, said many businesses needed to be better prepared for spikes in traffic, even though the number of incidences of such problems were reducing.

But he added: "Ryanair is very reliant on people going directly to its brand, and little of its traffic comes from those searching generally for cheap flights. It also has few competitors that offer exactly the same routes or prices. Customers are likely to be more patient than with Ryanair, than with other companies that are reliant on search engines and face customers switching quickly to rivals."

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