"It's hard to measure if it boosts sales or not," he says. "Load factor (the number of seats sold for flights) has always been in the 80 to 90 percent range. But it did bring Nok Air into the limelight in terms of brand awareness."

If anything, the charismatic CEO believes the added publicity brought a change to the passenger mix.

Before the photo shoot, international travelers made up 10 percent of the passenger manifest. After the shoot, the percentage jumped to 18 percent based on passport checks.

With Nok Air set to make its first international flight -- to Yangon, Myanmar, in the third quarter of 2013 -- Sarasin says: "It's good timing."

Offensive: Is "sexy" a bad word?

Thailand's Ministry of Culture received complaints from local organizations and critics who were shocked by Nok Air's sexy photo shoot, according to local Thai media.

One fear was that the photo shoot might propagate Thailand's image as a destination for sex travel -- but the Ministry of Culture says no laws were broken.

"The Ministry of Culture didn't call me. In fact, I received no call from any government agency," points out Sarasin. "We were all careful not to expose the women to be too naked."

Contacted by CNN, the Ministry of Culture says it's no longer commenting on the matter.

While sex appeal is the blatant strategy for Thailand's Nok Air, further north "sexy" is a bad word in the Korean airline industry -- which is not the same as saying that Korean carriers don't value what might politely be called "attractiveness."

"Projecting any sort of sexy image in a flight attendant interview would be hugely risky here," says Mi-kyung Chung, a former flight attendant who now teaches at the Airline News Center (ANC) flight attendant academy in Gangnam, Seoul.

This might come as news to flight attendants on South Korea's Asiana Airlines, whose union has been in a long-running conversation with the airline about ending its skirts-only dress code and relaxing strict guidelines for hairstyles and makeup. In February, the airline said it would adopt a trousers option on its next uniform renewal.

With a "few thousand students" -- mostly women -- ANC is considered the largest flight attendant academy in the country. The school charges $1,440 for an all-inclusive package in which students can take classes for as many months -- or years -- as they need.

Despite Korean Air's obvious use of old fashioned sex appeal in its widely distributed "For life on a whole new scale" series of advertisements, professionals insist that sex isn't the primary appeal.

Instead of sexy, "bright, clean and sophisticated" is the look that's most sought after in the recruitment process for Korean airlines, according to Jinah Lee, a flight attendant turned ANC lecturer.

Korean airlines have been setting the standard for flight attendants for almost a decade now, says Eunice Kim, head of BCCA flight attendant academy in Shinchon, South Korea, which specializes in foreign airline recruitment.

She admits that looks are part of the package.

"Recruiters for the foreign airlines I work with often tell me that Korean flight attendants are much more good looking and better to work with compared to flight attendants from other countries," says Kim.

She says the BCCA's 2,200 students include many foreign-educated young women, "NYU grads," PhDs and graduates from the top universities in Korea.

According to Kim, a number of foreign students come to South Korea to study at the academy. Some, she says, even undergo cosmetic surgery during their stay in the hopes of being recruited by foreign airlines.

When asked about the demand for Korean flight attendants at foreign airlines, Kim cites "high education rates ... good teeth, complexion, height and positive outlook" as attributes.

In addition, Korean flight attendants embrace the service mentality more completely, says the BCCA head.

"Personally, I think it comes from the conservative Confucian background, where women were expected to do a lot of the service in the household," says Kim.

Attitude trumps looks

The sentiment is similar in China, where the Foreign Airlines Service Corporation recruits Chinese flight attendants for foreign airlines, such as Emirates Airlines and Qatar Airways.