WiFi On-Board: How does In-Flight WiFi Work?

By Sumanth Bharadwaj | April 21, 2020

Isn’t it frustrating to switch off your phone and not stay connected with your friends through social media while travelling in an aircraft? Or how about unable to watch your favourite show on Netflix? Fortunately, this is changing. In-flight WiFi is becoming more common on aircraft these days. Many airlines around the globe are starting to offer WiFi internet services on-board to help them stay connected with their loved ones. But how does an aircraft offer WiFi when it flies 38,000 feet high and 400 knots fast?

An illustration showing antennas placed on an aircraft providing WiFi service ©Gizmodo

How does aircraft WiFi work? 

To provide WiFi to passengers in the air, airlines use either land-based towers or satellites. Land-based internet is similar to cellphones. Cellphone towers beam 3G internet to aircraft fixed with antennas. This technology is called Air-to-Ground (ATG). Two or more antennas are fixed on the belly of the aircraft to capture signals from cell towers. Since aircraft travel at 400 knots (800 km/h approx.), at a certain point, it has to connect to another cell tower. Some antennas do this with motors that tilt towards the tower capturing the signal. However, ATG provides with only 3-Mbps of bandwidth making ineffective to stream videos. But internet speeds are rising as technology advances. Also, this technology does not work when aircraft flies over oceans, such as transatlantic routes. This is where satellites come into the picture.

The bump with the antenna inside fixed on top of an aircraft to receive WiFi signals. ©Flickr

Satellite WiFi, the future of in-flight connectivity

The other method to receive WiFi signals in-flight is to connect to satellites in geostationary orbit. Antennas placed inside of a radome on top of an aircraft connect to Ku or Ka-band satellites. It offers a broader bandwidth although signals from satellites are transmitted over hundreds of kilometres. The Ku-band satellite offers up to 30-Mbps WiFi speed, making it easy to stream videos or video call your business partners. Gogo, one of the largest in-flight WiFi providers, introduced a 2 Ku-band technology which uses two antennas to offer speeds up to 70-Mbps.

Interestingly, radomes covering antennas placed on top of an aircraft creates a lot of drag. To reduce the drag and eventually save fuel, thinner radomes have to be designed. A company named Kymeta is developing a new kind of an antenna called “mTenna” – which is less than half an inch thick and 20-40 inches in diameter.

Kymeta “Mtenna” ©Wired

Numerous airlines across the US, Europe and Asia offer in-flight services but for a price. There are major airlines like Emirates, Norweigan, Air China, Qatar Airways and many more which offer free in-flight WiFi. Other airlines too will join the race as customer demand for in-flight WiFi is increasing. 

Currently, around four billion passengers fly every year around the globe with only 25 per cent of aircraft equipped to serve in-flight WiFi. In 2018, the airline industry collected ancillary revenues up to $1 billion for providing in-flight internet.

Ancillary revenue from in-flight internet service is expected to reach $30 billion in 2035 as IATA forecasted that the number of passengers would double to 8 billion in the next 20 years. Over the next few years, connectivity will increasingly become a standard aircraft feature.

This content was provided to MentourPilot by provider, Travel Radar Media. Travel Radar offers high quality content in partnership with Mentour


Leave your comment