But my favorite perk here is definitely this flat bed.

These fancy perks are some of the reasons why more than 20 million passengers voted Singapore Airlines as the top airline this year.

The airline won the coveted award after nine years of losing out to rivals like last year's winner Qatar Airways, and top competitors like ANA and Emirates.

And what does it take to become the world's best airline?

I'm here at Singapore Airlines' training center to find out.

Let's go!

Ask the company and its fans what sets it apart, and you're going to be hearing the word 'service' a lot.

And the face of that service is the Singapore Girl.

The airline's flight attendants are known colloquially as Singapore Girls.

Since the 1970s, the airline has featured them prominently in its marketing campaigns, promoting the brand's focus on hospitality.

She's so iconic she even has her own wax figure in the Madame Tussauds museum.

Some people may think a flight attendant is just a waitress, but the acceptance rate of becoming a Singapore Girl is as low as top universities like Harvard and MIT.

We're looking at about 1,200 people on the average, a year.

And training would be 14 weeks of bringing someone new to the industry and transforming them into the Singapore Girl.

But this uniform is not an easy one to earn.

Called a sarong kebaya, the Singapore Girl's uniform is originally a traditional outfit worn in Southeast Asia.

But Singapore Airlines can boast that its version is haute couture.

It was designed by French designer Pierre Balmain in 1968.

I felt really proud and happy to be able to don the kebaya. Such a pleasure to have this on.

For all the stewardesses, we have different sets of uniforms each year, tailor-made to our body shape.

But it's not just about looking pretty.

There are strict guidelines to follow to achieve the desired professional appearance.

So what I have on with me right now is the French twist, which is one of our signature hairstyles.

So there are some girls who end up having to cut their hair and so on?

Yes, that's right.

Ooh, interesting.

No crazy nail colors then?

No, not a lot.

So you may think that being a Singapore Girl is just about being pretty.

But we're just getting started.

Elizabeth is going to teach me the basics of serving.

Let me introduce your baby for today.

There're a few rules that you need to take note when holding the tray.

First of all, do not touch the tray to your body, and make sure that it's at your waist level.

And then, you have to hold it parallel to the aisle so we do not hit the passengers.

And most important, you must have a strong grip of the tray.

And there's the pouring of the champagne, which is a lot harder than it looks.

Okay, don't touch the rim.

Ah, I already touched the rim!

But before customers even board their flight, there's the lounge.

You know you've made it, when you get to the private room.

It's the most exclusive part of the SilverKris lounge and it's only open to first class and suites passengers.

The best part? You get to enjoy yourself with a view of the plane you're about to board.

And if you don't enjoy that, you could just get table service.

And if all else fails, you can always get a drink at the bar.

But does being the world's best airline always mean good business?

In the challenging airline industry the answer is not always clear cut.

Nitin Pangarkar has been studying the airline for decades.

He says that it's still perceived as the gold standard in service.

They smile at you, some people say it's fairly robotic.

Whether it's robotic or not, I would like somebody to smile at me.

But its profitability came into public focus when it posted its first quarterly loss in five years in 2017.

They provide good service. There's no doubt about that.

That's one index of performance. But the other index of performance is the profitability, right?

The profitability will allow you to keep providing excellent service.

If you don't have profitability you can provide excellent service today but you may not be able to continue to do so.

The company should be on track to better earnings.

Last year it launched a transformation program which helped it this year to record its best full-year profit in seven years.

Yet that transformation stirred debate after the airline put in new pricing policies like charging some passengers for seat selection.

Some say that has diluted its 'X' factor in service, but Pangarkar warns that service is not king in the airline business.

Good service and profitability definitely do not have a correlation of 1.0.

In an industry where innovation is quickly copied, Singapore Airlines is still trying to be a first mover.

This month, it became the first airline to launch a digital wallet powered by blockchain technology, allowing its members to use frequent flyer miles to pay for facials, sandwiches and even gas.

For now, passengers are saying that the airline is the best way to fly.

But in a competitive airline industry, there's no guarantee that there will be blue skies ahead.

Hi high flyers. It's Xin En. Thanks for watching.

If you want to check out more of our videos, we've got one on India and another about the World Cup.

As always, feel free to leave any suggestions for future videos in our comments section.

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