Cathay Pacific will introduce its all-new premium economy service in March 2012, with Sydney travellers among the first to sample the seats and cabin.

The Hong Kong flag carrier has earmarked the daily Sydney-Hong Kong service CX100 and CX101 for aircraft which have been upgraded to accommodate the 28 new seats sandwiched between the airline's new business class and economy sections.

Cathay Pacific has yet to formally announce its new class of travel and reveal the seats and extra services you'll get, but the airline's CEO John Slosar has previously pledged to "deliver something special -- not just an economy seat and call it premium."

Earlier this year Alex McGowan, Cathay's General Manager for Product, revealed his "premium economy playbook" to Australian Business Traveller by suggesting as "a quiet cabin, a more exclusive environment, with a larger more comfortable armchair that you can really sink into, recline and relax in."

"I think that any premium economy product needs to be its own seat, which needs to be wider and have more (legroom), it needs to have a legrest and footrest and be a better all-round experience." McGowan also called out "upgraded catering and a larger (video) screen size" as key components.

"But it mainly is about being a small private cabin, set separately and having more interaction with the cabin crew and a better standard of service (compared to economy)."

However, the airline is keenly aware of the need to sharply differentiate premium economy from business class in order to protect its pointy-end profits.

"The key with something like premium economy is to understand that it's an economy plus product, not a 'business class minus' product -- at least from a philosophical perspective, but not as a product definition" McGowan told Australian Business Traveller.

"It's not seeking to capture people who want to trade down from business class because realistically if you're a frequent business traveller who has important deals to do when you get to your destination, you need that flat bed and you need an environment that's conducive to sleep and work so you can be at your peak when you arrive."

"Trading down from business class into premium economy is not the game we're in. It's for people in economy who want more space, more exclusivity, and a few details like better catering and wine. It's also about capturing people who may want not to travel in economy but can't afford to travel in business class."

According to advance flight schedules logged by Cathay Pacific into the global distribution system (GDS) used by travel agents and reported by Airline Route, the daily Sydney-Hong Kong service CX100 and CX101 will be first to sport the new cabins, along with flights from Hong Kong to Toronto, Singapore and Shanghai Pudong, on both Airbus A330 and Boeing 777-300ER aircraft.

There's no word on if the aircraft refit will also include new economy seats, a project on which Cathay Pacific is "working quite aggressively".