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Bridging the gap between business and cattle class is premium economy. This once novel concept is now increasingly being adopted by airlines that are seeing financial benefits in offering passengers that little bit more comfort for a little bit more money.
Even the US has finally caught up, with American Airlines now selling premium economy seats on its Boeing 787-9 Dreamliners on selected international routes from Dallas, and also between Chicago and Paris from July 5.
Delta Air Lines is also expected to announce new premium economy cabins on long-haul aircraft later this year, while Aer Lingus is thought to be considering adding the class to some of its fleet.
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An airline with the best food, service and seats in the world? Traveller.com.au's writers name what their dream plane would feature.
See also: Is premium economy worth it?
But what does paying extra for a premium seat actually get you?
As you will see from our airline-by-airline comparison below, the standards of premium economy differ greatly, with passengers being lavished with anything from "free" drinks and amenity kits, to extra legroom and hi-tech gadgetry.
The average premium economy seat is about 18 inches (45cm) wide, with perhaps 37 or 38 inches (93 or 97cm) of pitch (leg-room).
But a comparison reveals that Norwegian offers the most leg-room in the air, at 46 inches, while Virgin Atlantic's service offers the widest seats, at 21 inches.
Industry experts say those who already fly business class don't tend to want to "buy down" to premium economy, as they are used to the enjoyment, say, of a bed that's 22 inches wide.
The premium customer, therefore, is typically one who regularly flies economy but sees the value in paying a bit extra for added comfort on a longer flight.
Airlines need to get the balance just right though. Spacious seats once offered on Boeing 777-300ERs by Turkish Airlines and Air New Zealand are now being phased out.
See also: What do you get in premium economy?
Turkish once offered "Comfort Class" seats that were a roomy 19.5 inches wide but this meant it could only fit seven into a row - as in some business class cabins. With other airlines making more profit as they could fit in eight, the service was scrapped.
Air New Zealand's Space Seat, added in 2010, looked stylish and offered passengers more privacy but not much by way of extra legroom (see below).
The airline is now instead going to refurbish its Boeing 777-300 fleet (which operates from London Heathrow) with a new "luxury leather" premium economy seat from October 2017, which will feature on the route from Heathrow to LA.
Qantas has been boasting recently of the recline on its new Dreamliner seats, which it says will offer a wider and more functional space when they launch in October - without annoying the person behind.
The seat is almost 10 per cent wider than Qantas' existing premium economy offering, details of which are below, and has several sections that move to support your body during recline.
Other recent premium economy additions include the goodies that come with Cathay Pacific's A350-900 aircraft, flying from Gatwick (and Manchester from June). Seats come with dedicated tablet holders, power outlets and USB ports - for those who like to fly with their gadgets - as well as fully integrated leg rests.
In-depth airline by airline guide
Seat pitch and width: More legroom and up to one inch (2.5 cm) more room at knee level, so 40 per cent more space compared to Economy.
Meal options: The meal service has been upgraded, with a second hot dish added and new gourmet offer on flights longer than 8 hours. This is presented in eco-designed tableware created by the Catalan designer Eugeni Quitllet.
Do chairs recline or extend? Recline within a fixed shell.
Are any drinks free? Begin with alcoholic/non-alcoholic aperitifs, followed by wine and Champagne
Are snacks free? Various snacks are available throughout the flight, including a self-service buffet on longer flights. Meals start with crackers.
Any boarding benefits? SkyPriority: priority from check-in all the way to boarding with security fast-track at selected airports.
Any luggage benefits? Check-in 2 x 23kg; carry-on 18kg (2 items + 1 accessory)
Any other benefits not covered above? Wide HD touch screen. Noise-cancelling headphones, power outlet, reading lamp. Travel kit: toothbrush, toothpaste, socks and eye mask. Soft wool blanket, feather pillow and blanket. Bottle of water.
Air New Zealand
Seat pitch and width: 42" seat pitch
Meal options: A selection of Business Premier options are served from a menu designed with chefs, Peter Gordon and Michael Meredith. Premium Economy passengers can expect to sample high-quality cuisine, complemented by premium New Zealand wines.
Do chairs recline or extend? Spaceseat: Centre seats for couples (with retractable armrests), angled outdoor seats for more privacy. Leather seat: Luxurious leather seat with generous armrests and adjustable leg and foot rests – enjoy more legroom with the largest seat pitch in its class and relax with 50 per cent more recline than Economy.
Are any drinks free? Yes all drinks are free.
Are snacks free? Free snacks are available at the click of a button from the personal entertainment screen.
Any boarding benefits? There is a separate check-in for premium passengers.
Any luggage benefits? 2 pieces checked-in luggage, max 23kg. 2 pieces carry-on luggage up to 7kg each.
Any other benefits not covered above? Guests in Premium Economy have access to premium check-in, free amenity kits, high-quality headphones, bottled water and have quicker access to their baggage on arrival. Amenity kit includes New Zealand made Antipodes skincare pawpaw and avocado lip balm, socks, eyeshades, toothbrush kit, earplugs and a pen.
Seat pitch and width: pitch: 38", width 19.3"
Meal options: Premium Economy meals are the same as in economy but followed by Business Class desserts.
Do chairs recline or extend? The chairs recline and offer a 17 per cent larger seat than in Economy. They also have adjustable head, leg and foot rests.
Are any drinks free? Yes, meals are accompanied by Business Class wines and sake. Sparkling wine is also available between meals.
Are snacks free? Snacks such as soup, and mini ramen noodles are available between meals.
Any boarding benefits? Priority check-in and luggage handling. Customers can also use Star Alliance partners' Business Class Lounge at Heathrow Terminal 2 and the ANA Lounge at Tokyo Haneda Airport.
Any luggage benefits? Passengers are allowed 46kg (2 x 23kg) of checked-in luggage.
Any other benefits not covered above? A 10.6-inch LCD widescreen touch panel. A universal power port, USB port, large-size table and personal reading light. Sony noise-cancelling headphones. Extra amenities, including plush slippers, toothbrush, an eye mask and earplugs. More than 390 programmes of fully-digital AVOD (audio-visual on demand) movies, TV shows, ANA original programmes, music and games (available in all classes). A WiFi service is available on most European routes.
British Airways World Traveller Plus
Seat pitch and width: pitch 38", 18.5" wide
Meal options: World Traveller Plus customers receive a three-course meal with options from the business class menu, as well as a full complimentary bar service. Meals are served on china with linen napkins.
On selected flights you can choose your main meal from the on-board menu between 30 days and 24 hours before your flight, for no extra charge.
Do chairs recline or extend? They recline..
Are any drinks free? All drinks, alcoholic or no-alcoholic, are free. A full bar service is provided for all cabins.
Are snacks free? All snacks are free in World Traveller Plus, in all cabins on long-haul flights and on request in economy.
Any boarding benefits? No.
Any luggage benefits? A larger free baggage allowance of two checked bags, each a maximum of 23 kg (51lb).
Any other benefits not covered above? A 10.6 inch personal touch screen with noise-cancelling headphones. Personal in-seat power sockets compatible with UK/US/EU plugs, plus two USB sockets. A fleece blanket, amenity kit and hot towel service. A smaller cabin with a maximum of 35 seats per aircraft.
Seat pitch and width: Pitch is 38" - 40" (40" in A350) and width is 18.5" - 19.5" (19.5" in B777-300ER)
Meal options: Premium Economy passengers enjoy an enhanced onboard meal selection.
Do chairs recline or extend? On B777-300ER planes the seat has an 8" recline distance. On A350-900, seats recline by 9" distance to ensure passengers can relax in both sleeping and sitting upright position. There is also a full length leg-rest on all seats. Seats also feature a retractable armrest.
Are any drinks free? Premium Economy passengers are welcomed aboard with juice and champagne and receive a personal bottle of water for the flight. A selection of complimentary drinks are served throughout the flight.
Are snacks free? Additional complimentary snack choices include more fresh fruit, an energy bar and dessert.
Any boarding benefits? Priority boarding before Economy Class passengers.
Any luggage benefits? 35kg (1 piece at 35kg or max 2 pieces totalling 35kg), plus 1 cabin bag weighing 7kg.
Any other benefits not covered above? Premium Economy features a quieter, more spacious cabin than the traditional Economy Class. In the A350-900, new features include dedicated tablet holders that make it easy for passengers to enjoy entertainment content on their own devices, and exclusive power outlets and USB ports. Each Premium Economy Class seat has a fully integrated leg rest and an ergonomically designed seat.
A Wi-Fi service, for a small fee, is now exclusively available on A350 Cathay Pacific's aircraft. A dimmable personal reading light is available. Also features a brand new entertainment system, featuring 12.1 inch personal TV with connectivity, allowing passengers, for a fee, to browse the internet, send and receive emails and connect on social media. Access to the Cathay Pacific website, a number of partner websites and three live TV news channels is available free of charge.
An environmentally-friendly amenity kit and noise-cancelling headsets are provided.
Seat pitch and width: 38" pitch and 18"to 19" width, up to 50 per cent extra legroom.
Meal options: Served on porcelain tableware, with a welcome drink, and a small treat after the meal.
Do chairs recline or extend? 130 degree recline. They also have a footrest.
Are any drinks free? Drinks are included within all Lufthansa fares
Are snacks free? Snacks are included within all Lufthansa fares
Any boarding benefits? No.
Any luggage benefits? Two checked bags up to 23 kg each.
Any other benefits not covered above? Larger monitor, additional storage space on/around seat
Seat pitch and width: 46 inches and width 19 inches
Meal options: Two premium meals from a separate menu (dinner and a light breakfast) are included in long haul flights.
Do chairs recline or extend? The seats recline and there is extra legroom in front.
Are any drinks free? Yes fully complimentary.
Are snacks free? Two premium meals included.
Any boarding benefits? Priority check in desk, fast track security.
Any luggage benefits? Two items of 20kg checked luggage, plus hand luggage.
Any other benefits not covered above? Complimentary lounge access, USB charger, blankets and headphones provided, plus free seat reservation.
Seat pitch and width: 38"- 42" and 19.5" - 22.8" (up to 22.8" in the Dreamliner in October 2017)
Meal options: Choose from the Rockpool inspired International Premium Economy menu prior to select flights with Select on Q-Eat. During the flight they'll be able to enjoy a contemporary menu inspired by leading Australian restaurateur Neil Perry, all served on Marc Newson-designed tableware.
Do chairs recline or extend? The chairs recline by 9"
Are any drinks free? Yes, the on-board selection of drinks which include soft drinks, juices, water, wines and spirits.
Are snacks free? Yes
Any boarding benefits? Dedicated priority check-in counters and priority access to a dedicated boarding lane in selected international ports. Passengers can also check in online between 24 hours and two hours before their flight departs.
Any luggage benefits? 40kg allowance in Premium economy compared to the 30kg allowance in Economy.
Any other benefits not covered above? Power outlets and USB connectivity are provided. Multi-way adjustable headrest and integrated leg rest with fold-out foot rest. Complimentary comfort kits are offered on selected flights.
On the Dreamliners, from October 2017, an ergonomically designed headrest has a specially designed pillow and a re-engineered footrest. High-definition Panasonic inflight entertainment seatback screens are 25 per cent larger. Five individual storage compartments and two USB charging points are given per seat, as well as shared AC power and a personal LED light designed to minimise disturbance of other passengers.
Note: Rival Virgin Australia offers a 41" seat pitch and 19.5 inch width
Seat pitch and width: Width between 18.5 and 19.5 inches, pitch (legroom) 38 inches.
Meal options: In addition to the onboard menu, customers can also select from the new Premium Economy Book the Cook meal pre-order service. Dishes must be ordered at least 24 hours in advance.
Do chairs recline or extend? Each leather seat has an eight-inch recline. In addition, there is a calf and foot rest, plus a headrest and wings. The seat has been designed in conjunction with UK designers James Park Associates with inspiration coming from luxury handbags.
Are any drinks free? All drinks on board Singapore Airlines are complimentary in both the economy and premium economy cabins. In premium economy, customers can also enjoy Champagne.
Are snacks free? All snacks onboard Singapore Airlines are complimentary and may include crisps and chocolate, or sandwiches and fruit.
Any boarding benefits? Priority check in, bag tagging and priority boarding is standard for all Premium Economy customers.
Any luggage benefits? A baggage allowance of 35kg is offered - an increase on the standard economy allowance. Bags will be priority tagged to ensure prompt delivery at baggage reclaim on arrival. In addition, customers in premium economy benefit from increased frequent flyer mileage when they fly.
Any other benefits not covered above? Enhanced in-flight entertainment experience. Available are noise-cancelling headphones and a large 13.3-inch full HD monitor. Amenity kits.
Seat pitch and width: 35 inch pitch, 19.7 inches width
Meal options: Same meals but included in the price. Premium James Martin meals, unavailable on flights departing from US.
Do chairs recline or extend? Recline
Are any drinks free? Complementary alcoholic drinks, except champagne.
Are snacks free? One snack prior to take-off service plus a light meal/snack prior to landing.
Any boarding benefits? Choose seats online prior to departure. Check-in & Bag Drop open from 4pm-10pm at Manchester Airport. Separate premium check-in (not including Holguin in Cuba). Priority lane at Manchester Airport. Separate premium boarding.
Any luggage benefits? 25kg checked in baggage allowance – non US routes; 32kg on US routes. 10kg hand baggage allowance. Premium baggage is the first baggage taken off the plane.
Any other benefits not covered above? Amenity kit including headphones, pillow/blanket, additional content on IFE system, activity for infants, newspapers.
Seat pitch and width: Seats are 38", economy is from 32".
Meal options: Premium Economy passengers receive a four-course meal.
Do chairs recline or extend? Yes, seats have a larger recline than those in economy.
Are any drinks free? All drinks are free in Premium Economy and long-haul Economy. But Premium Economy passengers also receive a free glass of sparkling wine before take-off.
Are snacks free? Pre-landing light bites are complimentary.
Any boarding benefits? Premium Economy passengers are entitled to priority boarding.
Any luggage benefits? A larger luggage allowance of 23kg.
Any other benefits not covered above? UK airport lounge access; fast-track security; larger TV screen in seat back; duvets and pillows on night flights; noise-cancelling headphones; complimentary newspapers/magazines.
Seat pitch and width: 38 inch seat pitch, 21 inch seat width
Meal options: The menu is an enhanced offering served on china with stainless steel cutlery and a choice of three entrees, including a vegetarian option.
Do chairs recline or extend? Chairs recline and there is a foot rest.
Are any drinks free? Sparkling wine on boarding then all drinks are free throughout the flight.
Are snacks free? All snacks and meals are free. On the new 787 aircraft there is a Wonderwall in the galley area which houses snacks and drinks. Customers are encouraged to stand up, stretch their legs and help themselves to anything they would like.
Any boarding benefits? Priority boarding after Upper Class customers.
Any luggage benefits? Premium Economy customers can check in two suitcases up to 23kg each. Customers also receive priority luggage reclaim.
Any other benefits not covered above? Virgin Atlantic Premium Economy is a completely separate cabin with dedicated crew. There are also dedicated check-in desks at all locations.
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