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How Does In-Flight Wi-Fi Really Work?

How Does In-Flight Wi-Fi Really Work?

Most people always have this question in their minds. well here is an answer from Quora submitted by Derek Schatz

There are two primary methods to enable a passenger Internet connection on an airplane: satellite and air-to-ground. I’ll talk about some of the key points on each of those, then talk about the in-cabin WiFi access point part.

Air-to-ground

  • As the name implies, signals go from the airplane directly to antennas on the ground
  • Uses a network of ground cell towers across the continental U.S. (therefore does not work over water). These towers’ cells are much larger than those of the typical cell towers used for phones.
  • Uses a version of CDMA, just like Verizon cell phones
  • Antennas are on the belly of the airplane, looks like a small fin
  • As the airplane flies, the connection hands off from one tower to the next just like your phone does when you’re driving. Users don’t notice any interruption.
  • Network infrastructure is much cheaper than satellite
  • Bandwidth for the newest generation system (ATG4) is up to 9.8 megabits per second (Mbps) per airplane (shared across all users). This is enough for email and casual web surfing, but would get quickly exhausted if people stream video – so this is usually blocked.
  • Gogo is the top provider of this type of service.
  • Installed on over 1,000 aircraft operating on domestic routes in the U.S., including Delta, American, Virgin America, and Alaska
  • Plans announced in late 2014 by Inmarsat to partner with Gogo on a hybrid ATG+satellite solution for Europe

Satellite

  • Unlike air-to-ground, signals from the airplane go into space to an orbiting satellite and then down to the ground. These satellites are usually in geostationary orbit, 22,300 miles up.
  • Three types offer different levels of performance (bands indicate specific transmission frequency ranges):
    • L-band (e.g. Inmarsat Swift Broadband): pretty slow, max 422kbps per channel per airplane
    • Ku-band (e.g. Panasonic, Global Eagle, and Gogo): tops out at around 20-40Mbps per airplane. Speeds depend on how many airplanes are in the satellite’s transponder “footprint” (aka spot beam)
    • Ka-band (near future, satellites launching soon): promises even higher speeds
  • A modern satellite has dozens of transponders to support a large number of simultaneous connections, e.g. ships, airplanes, portable ground terminals
  • Leasing transponders (antennas) on satellites is very expensive, so this cost is usually passed on to the airline and the passengers. But Jetblue offers it for free.
  • The airplane’s antenna is on the top of the fuselage, under a bubble-shaped radome
  • The only choice for trans-oceanic routes, and routes flying closer to the polar region (since you can’t put cell towers in the ocean)
  • Using satellites means a few hundred milliseconds more latencies since the data packets need to go 22,300 miles up to the satellite, then roughly 22,300 miles back down to the airplane. New constellations of low earth orbit (LEO) satellites providing lower latency high bandwidth connections are in development since 2015, e.g. by SpaceX.
  • Installed base not large yet but growing, targeted initially for routes between the U.S. and Europe
  • As the airplane flies, the antenna on the top of the plane is steered or electronically aimed to stay pointed at the correct transponder on the satellite up in orbit. For long-haul flights, there will likely be a handoff from one satellite to another when moving between coverage areas. This happens via coordination on the ground, and the airborne users may only notice a very brief hiccup. From the satellite’s viewpoint, it switches airplanes from one transponder to the next as it moves between the beams pointed at the ground.

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Aerospace

Boeing 777-9 Begins Certification Flight Testing with FAA Onboard

Boeing 777-9 Begins Certification Flight Testing with FAA Onboard

The 777-9 has commenced certification flight testing at Boeing Field in Seattle. This is a crucial step under the supervision of our regulator to certify the airplane and deliver it to customers worldwide.

Amidst Boeing’s current challenges, the B777X stands out as a project that could revitalize the brand. It is highly anticipated, and Boeing is keen to clear FAA certifications to release it as soon as possible.

Boeing 777-8F vs Airbus A350F: Comparing two Premium aircraft : Click here

The aircraft is two years behind its initial commitment date. During this time, the company has rigorously tested it under various conditions to ensure its readiness for commercial service.

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Boeing has announced that the 777X will be used for both passenger and freighter services, depending on customer requirements.

Boeing’s 777X program has achieved a major milestone with the Federal Aviation Administration (FAA) granting approval to begin certification flight tests, marking a significant step towards the aircraft’s entry into commercial service.

Mega Comparison of Boeing 777x vs A350-1000 Aircraft : Click here

The European Union granted approval for this merger in February, and Korean Air anticipates U.S. regulatory approval by the end of October.

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Following Airbus’ breakthrough with Korean Air, Reuters reported in April that Korean Air was considering a new Boeing order focused on the 777X, an advanced version of the 777 mini-jumbo.

Boeing 777-9 First certification

The first certification flight test of the 777-9 took place on Friday evening, with FAA personnel onboard alongside Boeing’s pilots and flight test team.

According to The Seattle Times, the aircraft departed from Boeing Field shortly after 6 p.m. and landed nearly two hours later after flying along the Washington and Oregon coast.

The 777X, an upgraded version of the successful 777 twinjet, features new engines and carbon composite wings with folding wingtips to accommodate standard airport gates.

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The first variant, the 777-9X, is designed to carry 426 passengers in a two-class configuration for long-haul international flights.

Comparison of two legendary aircraft Boeing 777x vs Boeing 747 aircraft : Click here

Boeing B777x total orders

Boeing has secured 481 orders for the aircraft, with Emirates being the largest customer, having ordered over 200 units. The planemaker has already built and stored 22 777X jets, with an additional six in various stages of assembly in Everett, Washington.

Boeing is close to finalizing a significant deal to sell approximately two dozen 777X jets to Korean Air, with an estimated value ranging from $4 billion to $6 billion, as reported by Reuters.

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Industry sources suggest that the agreement could be concluded as early as the Farnborough Airshow in July. Korean Air, South Korea’s largest airline, has been in discussions about returning to Boeing for its long-haul aircraft needs.

The Boeing 777X vs A350 is one of the most popular comparisons among aircraft as of now. The Airbus A350 has been operating for more than eight years, and its promising performance helps airlines in terms of efficiency and customer satisfaction, particularly in noise and vibrations.

The next generation Boeing 777X can fulfill the same requirements, with 777x first delivery given to Emirates Airlines, the launch customer for this aircraft. It remains to be seen how the Boeing 777X vs Airbus A350 will compete against each other in the future.

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