A Singapore Airlines Airbus A380 aircraft.

My previously high regard for Singapore Airlines has been sinking quickly in the last week. Dealing with its agents regarding an award ticket has been one of my worst airline experiences in years. Now we learn that the carrier did little to help a passenger who suffered a heart attack during a flight last month.

When I wrote about Singapore’s “maddening perfection” in September, I pointed out that it deserves all the accolades it gets for its on-board products and in-flight services. However, the airline hasn’t quite understood that being a global first-class company means much more than that.

I usually try to stay calm with airline agents on the phone and give them the time they need, even when it’s clear they are not very good. That turned out to be a serious challenge last week with Singapore agents assigned to the carrier’s frequent-flier program, KrisFlyer. It’s stunning how poorly trained they are, even though they are based in Singapore — not India, as their accents suggest. A few years ago, the carrier closed its Los Angeles call center, where agents were much better.

I wanted to change the dates of three out of four flight segments on an award ticket entirely on Air Canada, Singapore’s partner in the global Star Alliance. I booked it a few months ago with the last KrisFlyer miles I’ll ever have. As usual, I’d done my homework using the All Nippon Airways’ website, which is the only site showing award availability on every Star carrier. All flights I requested had an open seat.

Normally, if a Star airline has provided a seat for mileage redemption on StarNet, the alliance’s “middleware,” any member has access to that seat on a first-come-first-served basis. You probably know how that system works from my columns about United’s StarNet blocking.

Still, there is a small chance an agent may not see exactly what I see, due to using different systems, time delays and other variables. So when I called Singapore, I gave the agent my first segment and asked him to check for availability. He wanted to know all three flights. I said I couldn’t book the return unless I knew for sure on what day my outbound flight would be. He responded that he couldn’t look for seats one by one, but had to collect all the information from me before searching.

Most airline agents can tell you immediately whether an award seat is available on a certain flight — they either look at inventory or, in rare cases, request a partner seat and see if the other airline confirms it. I later verified with several other Singapore agents that what my first agent told me is indeed how they do things over there. So I gave him all my three new flights. Having written them down, he wanted to read them back to me before starting his search. That took over a minute of odd stumbling over what one would have thought was someone else’s handwriting.

My patience was almost running out when the real shocker came — he asked on what number he could call me back once he had looked for seats. Seriously? Award seats could vanish in seconds, let alone in whatever time he needed to perform what apparently amounted to a rather complex task. I said I preferred to hold while he was searching.

After keeping me on hold for 15 minutes, he disconnected the call without coming back. I called again and went through the same motions with another agent. Following a 10-minute hold, he said one of the new flights wasn’t available. I went back to the All Nippon website — that seat was gone indeed. After all, it had been more than half an hour since I’d first called.

Make no mistake about it — I lost a seat because of the incompetence and poor training of the Singapore agents, as well as the carrier’s inefficient system. Such lack of professionalism is to be expected from a third-world airline, but not from a carrier that is often named the best in the world in various rankings.

Slightly off point, the second agent also said that another one of the flights I wanted was not available — however, the All Nippon site was still showing an open seat. Even now, several days later, that flight shows as available on the site. I just called Singapore and a third agent said she couldn’t see it. I wonder if Singapore does its own blocking these days, taking its cue from United.

In my September column, I also wrote about Singapore employees narrowly following rules and not applying their own best judgment to specific situations that inevitably arise during air travel. In other words, they don’t really exhibit much humane behavior.

I was still surprised to learn this week about an utterly puzzling Singapore decision in March.

Max Pearson, a co-host of “The World Today” BBC program to which I listen almost every day, flew to London on Singapore on his way back home from covering the Japan earthquake and tsunami. Shortly after taking off from Singapore, he suffered a heart attack. The airline refused his request to return to Singapore or divert the flight to the nearest appropriate airport, so he could get the care he needed.

Singapore says it took the measures it deemed necessary, implying that Pearson’s condition was not serious enough to justify a diversion. Obviously, diversions are very expensive for an airline, but they are covered by insurance. Plus, Pearson had what has been described by media reports as a “life-saving surgery” as soon as he arrived in London.

It remains to be determined if the more than 12 hours Pearson had to endure on the Singapore plane might have complicated his condition.

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