Cathay Pacific A350 has an antennae near its tail that connects with satellites to provide wifi.
Airlines are racing to connect their passengers through wifi that is becoming more widely available, faster and dropping in price.
The carriers say more passengers are demanding it and wifi can help make the journey smoother, with one airline saying it will lead to fewer medical diversions, minimise delays and help avoid turbulence.
And live social media posting from aboard the plane has also been cited by one aircraft maker as a way of encouraging airlines to lift their game to avoid getting bad reviews.
This Friday Cathay Pacific will be the latest carrier serving New Zealand to bring in wifi-equipped planes. Its Airbus A350XWB aircraft flying between Auckland and Hong Kong will allow connection via satellite throughout the 12-hour flight for just under US$20 although it is possible to log on for free through sponsored sites.
Guillaume Vivet, Cathay's product manager of communication and entertainment, said the trend to staying connected in the air was driven by what was happening on the ground in hotels, cafes and airports.
"Some of our passengers are expecting to see that kind of service on board planes - they expect to stay connected throughout their journey."
Rolling out wifi was part of a $1.8 billion upgrade of product throughout the airline.
"All the components are quite expensive and the satellite data is not comparable in any way to what you pay on the ground - it's a very large investment," Vivet said.
The most critical element was the antenna on top of the aircraft fuselage protected by the radome bump near the tail which communicates with satellites and the ground and a wifi network is created on board. In Cathay's A350 there's a modem in the cargo hold linked to between five and seven routers in the cabin.
As the aircraft flies around the globe it switches between satellites.
Since introducing the service mid-year on the A350 - the world's latest widebody plane to enter service - Cathay has found wifi is most extensively used on long-haul daytime flights and particularly by business travellers.
All the components are quite expensive and the satellite data is not comparable in any way to what you pay on the ground - it's a very large investment.
Middle Eastern carrier Emirates' introduced inflight wifi through internet service provider OnAir in 2014. It offers the first 10 megabytes of data free and said it sees the service as an essential value-add.
About 50 per cent of passengers on ultra-long haul flights of 12 hours or more use the service.
Demand was growing by about 5-10 per cent month on month. On medium-haul flights of between four and eight hours about a quarter of passengers used the service.
Passengers most frequently use Google, Facebook and Snapchat.
The Civil Aviation Authority said more aircraft now have avionic shielding that provides additional protection from interference from portable electronic device transmissions and enables operators to install wifi systems into an aircraft.
Aircraft are now being manufactured with equipment that meets the standards that have been developed to enable electronic devices to be used safely in flight.
"Essentially the electronic device and satellite technology has become more sophisticated and prevalent and the modern avionics on airplanes are making them more resilient against potential interference," an authority spokeswoman said.
The authority allowed the use of transmitting and non-transmitting portable electronic devices if the operator of the aircraft had determined, and the CAA confirmed that this would not cause interference with any aircraft system or equipment in the aircraft on which it was operated.
"However, given the growing trend towards the use of transmitting portable devices on aircraft, the CAA intends to review its current policy as we have particular concerns around passengers not listening to important safety messages and the stowage of devices during critical stages of flights."
Air New Zealand, Qantas and Virgin Australia are rolling out wifi from next year. Hong Kong Airlines, which starts flying to Auckland next month plans to begin introducing wifi on board all aircraft in late 2017.
Air New Zealand will start with wifi on its transtasman flights.
Proving flights would begin in the second half of next year and internet services would be progressively available on Tasman, Pacific Island and long-haul jet fleets from the end of next year.
Internet connectivity will be supplied by Inmarsat's new global GX satellite constellation and integrated with Air New Zealand's in-cabin Panasonic Avionics technology.
Domestic New Zealand jet services were likely to offer a wifi service from 2018.
The airline's chief executive Christopher Luxon said earlier this month that given the airline operated some of the longest flights in the world, and in oceanic areas where there has historically been poor quality satellite service it had worked "patiently" with partners until it was comfortable with the standard of service.
We're finding it's a big plus for business travellers flying from Auckland to Los Angeles who couldn't previously access wifi on that route, which on a business trip means 12 hours where you're getting behind on emails.
It will release its pricing regime early next year.
Wifi penetration is high in the United States and it is used by the two US carriers now flying directly across the Pacific. American Airlines charges US$19 for the 12-hour flight and United US$17 for the leg.
American Airlines country manager for New Zealand Mario Santander said international wifi had been very well-received by passengers on the Auckland-Los Angeles route.
"We're finding it's a big plus for business travellers flying from Auckland to Los Angeles who couldn't previously access wifi on that route, which on a business trip means 12 hours where you're getting behind on emails."
Qantas has teamed up with global broadband services provider ViaSat for a service that it said would feature speeds up to 10 times faster than conventional on-board wifi, giving passengers the ability to stream movies, TV shows, the latest news bulletins and live sports on domestic flights via the internet.
In-flight trials are expected to begin with a single Qantas Boeing 737 aircraft in late 2016, retrofitted with equipment to enable high-speed wifi.
A full roll-out across Qantas domestic's fleet of A330s and Boeing 737s is planned from early next year, with the aircraft to be fitted with modems and the advanced antenna that receives the satellite signal.
Qantas says pilots will also benefit from wifi.
"Pilots can stream richer information on real-time weather conditions expected along the flight path. They can use this to dodge areas of turbulence and make better use of tailwinds to reduce flying time."
AirlineRatings.com reports that the head of A350 XWB marketing customer affairs Marisa Lucas-Ugena said at an Airbus event last week that wi-fi connectivity gave passengers the chance to give live feedback on the planes they were in - both positive and negative.
"Any passenger having a great experience in flight can report it real time," she said.
A tech security firm warns that inflight wifi is vulnerable to cyber theft.
NordVPN said planes were unique hacking grounds - more dangerous than airports or coffee shops, as they cram passengers in one small space for hours.
"This gives plenty of time and opportunity for hackers to access all data that's being transmitted over open networks. Passengers who do online banking, shopping or business emailing are especially vulnerable to identity and data theft," the firm says.
Last year there were already 52 airlines worldwide offering in-flight internet, and the prevalence of in-flight wifi had grown 1600-fold since 2013 in the United States.
Passengers can protect their data in several ways.
First, a traveller gets to designate the wifi network as home, work or public.
The safest option for airplane passengers was the Public network setting - as this option is created to make sure it's not visible by other computers.
"Secondly, travellers have to make sure they are connecting to the wifi network offered on the flight, and not a look-a-like network with a similar-sounding name that might be spoofed," said NordVPN.
The firm, which sells its virtual private network services, said VPNs were becoming essential in the world of tightening online security.
"Unfortunately, some in-flight networks cut back on security and block VPNs, but in most cases users have no obstacles for using virtual private networks."
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