Aerospace

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.

Top 6 Largest Passenger Aircraft in the World. (Opens in a new browser tab)

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Aerospace

Which is bigger 777x or 787 aircraft ?

The 777X is a new series of the Boeing 777 family and is designed to be larger and more efficient than its predecessor. It features two variants: the 777-8 and the 777-9, being the larger of the two.

The Boeing 777X emerges as the larger sibling within the Boeing family, representing a significant leap forward in both size and efficiency. Comprising two variants, the 777-8 and the 777-9, the latter takes the crown as the larger of the two. With its expansive fuselage and impressive wingspan, the 777X is tailored for long-range journeys and boasts a substantial passenger capacity.

On the other hand, the Boeing 787, affectionately known as the Dreamliner, occupies a niche in the market as a smaller yet formidable aircraft designed for medium to long-range flights. Its distinguishing feature lies in its composite fuselage, a technological marvel that renders it lighter and more fuel-efficient compared to conventional aluminum counterparts. The Boeing 777X is larger than the Boeing 787 aircraft.

When it comes to passenger capacity, the 777-9 reigns supreme, typically accommodating a sizeable contingent of 400-425 passengers in its standard configuration. In contrast, the 787, with its more modest dimensions, typically carries between 240-290 passengers, depending on the variant and layout.

One of the remarkable innovations introduced with the 777X is its folding wingtips, a feature designed to address the logistical challenges of accommodating such a large aircraft in conventional airport gates. These folding wingtips enable the 777X to retract its wings, allowing it to fit into gates designed for smaller aircraft while still reaping the benefits of an extended wingspan during flight, thereby enhancing fuel efficiency and operational flexibility

Aerospace

China Secures Production Certificate for Mass Production of Pilotless eVTOL Aircraft

EHang

The first passenger-carrying pilotless electric vertical takeoff and landing (eVTOL) aircraft in the world, the EH216-S, has received the Production Certificate for its eVTOL aircraft from the Civil Aviation Administration of China (CAAC).

This is a significant milestone for EHang Holdings Limited, the leading UAM technology platform company in the world. This outstanding accomplishment is another big step towards mass manufacturing for the eVTOL aircraft and the ensuing commercial operations, building on the ground-breaking acquisition of the Type Certificate and the Standard Airworthiness Certificate for the EH216-S.

The PC is a crucial certificate that the aircraft maker receives from the CAAC, the country’s aviation authority. By obtaining this certificate, EHang has demonstrated that it has set up a quality management system for mass production that satisfies the airworthiness regulation standards set forth by the CAAC, and the company has been given permission to continue producing mass quantities.

It is also a strong guarantee of the calibre of the goods made by EHang. Raw materials, supplier management, manufacturing organisation, production quality control, aircraft pre-delivery test, after-sales repair and maintenance, etc. are all included in the mass production quality management system for the EH216-S.

To ensure that every aircraft and its components that roll off the production line strictly adhere to the approved type design and safety requirements, the system sets clear guidelines and documentation for every step in the production procedure. This ensures comprehensive traceability and safety control.

Aerospace

Four Airbus A380 Superjumbos lined up to be scrapped

EASA Proposes AD for Airbus A380 Wing Rib Foot Cracks

In a strategic move aimed at reclaiming valuable resources from the iconic Airbus A380 aircraft, VAS Aero Services and Dr. Peters Group have announced a significant collaboration.

This partnership marks a milestone in aviation logistics and aftermarket services, with four of these colossal planes slated for teardown and redistribution of used serviceable material (USM).

The venture between VAS Aero Services, renowned for its expertise in aircraft dismantlement, and Dr. Peters Group, a prominent Germany-based investment fund management firm, underscores a commitment to sustainable aviation practices. This isn’t their first foray into scrapping A380s; their successful partnership has already seen the dismantlement of these aircraft, making them pioneers in this niche.

Under the agreement, the latest consignment brings the tally to eight A380s entrusted to VAS by Dr. Peters Group. Managing Director Christian Mailly of Dr. Peters Group emphasized the trust placed in VAS, citing their unparalleled capabilities in dismantlement and aftermarket sales network. It’s a strategic move in response to the growing demand for quality USM parts, particularly with the resurgence in reliance on the A380.

Notably, the teardown process will be carried out at various locations, optimizing the positioning of harvested parts to cater to different markets. While some parts will be positioned in Europe to support operators in the region and the Middle East, others will remain in the Asia-Pacific region. This meticulous strategy ensures efficient access to spare parts, benefiting MROs and airlines across these markets.

The decision to retire these A380s comes at a time when operators are reassessing fleet strategies amidst evolving market dynamics. Despite initial plans for quick retirement due to the emergence of more fuel-efficient alternatives, factors such as a rebound in long-haul demand and delays in new widebody deliveries have prompted operators to reconsider. The A380, with its unique capacity and capabilities, presents a practical solution for short-term capacity management.