Internet in the clouds

A few years ago, we had to leave the working world when boarding an aircraft. We could not make phone calls or respond to emails, follow market developments online or stay in touch with colleagues at work. If we wanted to watch a film, we had to make sure that an in-flight film had been pre-selected for us. For some it was an escape from modern technological pressure, but for others it was a frustrating suspension of business and an inefficient use of the hours spent on a plane with no way of taking part in the work pace at all.

We have come a long way in the last decade thanks to great progress. We are living in a world where the need for internet access is prevalent, almost non-stop. The ability to connect and carry on at our pace of life is literally within arm's reach. Business no longer has to stop just because we are in the air.

Modern wireless router technology lets us use Wi-Fi at home or connect to a public service in a town, a café and, last but not least, on an aircraft. Devices such as a laptop, tablet or smartphone search for and recognise the nearest hotspot and can connect to it.
Just as with home networks, you can choose between wireless and wired connections. On an aircraft too, you can decide whether to allow your device to access shared information via Wi-Fi without using cables to connect to a physical data port; some aircraft offer a private connection via cable. Without the aircraft's connection to the internet, such a connection would only serve to consume content on a server located in the aircraft. And what next?

How it works

Have you ever wondered how Wi-Fi gets onto aeroplanes? It can be done in two ways. One is a direct connection of the aircraft to special ground-based mobile towers. The other uses satellite Wi-Fi. If the aircraft has a Wi-Fi connection, it is important to distribute it among the passengers.

But how exactly does Wi-Fi work on aircraft? Take Gogo as an example. It is one of the largest providers of internet on aircraft, and it uses ground towers and satellites all over the world. Gogo serves airlines such as Delta, United, Alaska Airlines, Virgin Air, or Steve Nolan. Other in-flight internet providers are based on a similar principle.

Ground-based mobile towers

Ground-based mobile towers provide a comprehensive 4G network, which stretches along the route in every developed country. Aircraft then receive the signal using an antenna mounted on the underside of the aircraft, which tries to get the best signal from these towers. This is one of the first ways of providing Wi-Fi on aircraft. It is similar to the towers that supply signal to mobile phones, but of course adapted to serve a fast-flying target, with antenna systems aimed at the sky and frequencies suitable for long range.

The Wi-Fi access point inside the aircraft cabin is then connected to the GSM mobile network, which allows electronic devices to connect via ordinary Wi-Fi, giving you a full internet connection.

The strength and coverage of the signal will vary with altitude and the volume of network traffic, but it usually works just as it does at home or in the office. A noticeable difference comes as soon as you fly over the sea, where there are no ground-based mobile towers, and you will no longer have a connection. The network is only available at altitudes of 10,000 feet and above. Across Europe there are 300 ground stations, four of which are in the Czech Republic. Ground-based systems usually have an unlimited monthly data plan, which the owners of the aircraft pay for, and data use is included in hourly rates.

But how do you connect aircraft flying over the ocean?

Satellite connectivity

In a satellite network, aircraft connect to the internet using an antenna mounted on the top of the aircraft. They use different frequencies from the towers of the 4G cellular network.

This communication system connects the aircraft's antenna, located in the upper part of the aircraft, with a satellite orbiting in space. The satellite also communicates with a ground station that has a direct connection to the internet. When a passenger requests information from the aircraft's Wi-Fi access point, the aircraft's connection point passes the request to a geostationary satellite, which handles it via a point-to-point link with the ground station over a broadband radio link. Communication is duplex, and the connection can work with quite high transmission capacity; it is all just a matter of bandwidth. The only disadvantage is a noticeable increase in latency, even compared with an LTE network. The network of geostationary satellites hovers above the Earth's surface at an altitude of about 36 thousand km. The signal does travel at the speed of light, i.e. slightly over 1 billion kilometres per hour, but consider that this path is covered four times: from the aircraft to the satellite, from the satellite to the ground station, from the ground station back to the satellite, and from the satellite to the aircraft. We must also add the time needed for routing on Earth and the response of the ground servers with the content. If the ground station is in the USA, reading the content of the kvalitni-internet.cz server means that the communication must travel thousands of further kilometres by undersea cable to Prague, load the data on the server and send it back to the USA, then to space and then to a tablet connected to the Wi-Fi network in the aircraft. Adding up these values, you get latency of hundreds of milliseconds, up to a few seconds.

The reason for preferring a ground-based connection via an LTE network is therefore clear. Most satellite systems today also offer slower connection speeds than ground-based systems, but this parameter is gradually catching up. Access is charged per MB for each use. 

Wi-Fi distribution system on aircraft

An aircraft gets its Wi-Fi signal using ground-based mobile towers or satellites. Once it is connected, it is important to realise that the connection obtained must be distributed among the devices of the passengers on board. Each aircraft must therefore be equipped with four elements:
 

• A large specialised antenna
• Powerful radio transmitters for communicating with satellites or ground towers on a certain band of the electromagnetic spectrum
• A modem for receiving information
• A distribution system for sharing this bandwidth between the people and machines on the aircraft.

And these elements – the antennas, radios and aircraft systems – provide Wi-Fi on board the aircraft. If in-flight Wi-Fi improves, it will be thanks to better parameters in these components and systems.

Connection speed vs. parameters

Airlines use various pricing strategies for connecting passengers to the internet on board. Usually this means a variety of options in the form of a package based on data use, or different prices for connecting different devices – a tablet, laptop or smartphone. For other airlines, the deciding factor is the type of aircraft – Airbus or Boeing.

TIP: Also read our article Internet in schools

Paying for Wi-Fi in a package

The price of wireless Wi-Fi varies depending on the package the customer buys, either before the flight or directly on board. In terms of package strategy for accessing the internet, pricing schemes are highly variable: some carriers sell Wi-Fi for unlimited flights, while others charge for their Wi-Fi by time or data increments, where costs can rise quickly. Some airlines may also have different types of Wi-Fi systems, depending on the type of fleet – for example Airbus versus Boeing, or a domestic aircraft versus a long-haul international one. Every company providing Wi-Fi on board has a different strategy, but quite often it is a combination of the flight time during which the connection can be used, the megabytes consumed, or a longer-term connection if you travel regularly, even several times a month.

Wi-Fi for different devices

Many airlines charge differently depending on the type of device you connect, whether you need Wi-Fi for your laptop, phone or tablet. As smaller devices, such as smartphones, generally use less data, Wi-Fi is cheaper for them. But many people think this may be more of a marketing matter than anything else – businesspeople who use their laptops will pay a certain sum of money to get to work in the air.

The near future of Wi-Fi on aircraft

The cost of buying and installing better hardware on aircraft has fallen so far that many airlines have started investing in upgrading to new technologies. And, more interestingly and importantly, these technologies are moving to higher speeds, and even low-cost airlines are introducing Wi-Fi service on board their aircraft.

It is estimated that by 2019 most European carriers will have Wi-Fi connectivity available.

Inmarsat is working with Deutsche Telekom to develop the European Aviation Network [EAN], a high-capacity satellite network supported by ground towers. Inmarsat, as the operator of the satellite network, and T-Mobile, as the operator of the mobile network, have combined the advantages of both systems into one functional whole. Their aim is to achieve reliable high-speed broadband service in the air across Europe. EAN is ready to be launched. Airlines from the IAG group, such as British Airways, Iberia, Vueling or Aer Lingus, are equipping their regional aircraft with exactly this system. Passengers will be able to access the internet on board their aircraft in the middle of the year, and on around 90% of aircraft by the end of the year, by spring 2019.
"More than half of the world's aircraft will be equipped for in-flight Wi-Fi within the next two years," says Inmarsat. "By 2020, aviation connectivity is set to become a billion-dollar revenue sector."

So let us hope that one fine day ubiquitous internet on aircraft will serve the work and entertainment of passengers at an acceptable price and without data limits. For many of us, long-haul flights around the world will then become a considerably less boring experience.

What does Ryanair say in 2024 in answer to the question "Will there be Wi-Fi on board?"

Do you travel a lot and constantly use the internet somewhere? Also read our article Internet on trains. In 2024 it is almost standard.

Author: Aneta Babušová, Jakub Moník

Updated 19 February 2024