https://arstechnica.com/gadgets/2017/07/honeywell-airplane-inmarsat-satellite-internet/
Gear & Gadgets -
Taking a flight on the best Boeing 757
Checking out Honeywell's airplane test bed, and Inmarsat's new satellite
Internet service.
Sebastian Anthony (UK) - 7/3/2017, 12:22 PM
The 787 Dreamliner, with its composite-fibre chassis, lithium-ion batteries,
and super-efficient engines, can fairly claim to be the coolest airplane in the
world. Another reasonable choice, if you really revere giant flying tubes of
aluminium, is the gloriously ginormous Airbus A380. And of course, true
aerospace connoisseurs would probably choose the SR-71 Blackbird, or perhaps
even the Concorde. But I can tell you now, all of these planes pale in
comparison to the Boeing 757, built in 1982, that I just had the pleasure of
flying in.
Externally this 757, which was only the fifth of its type to roll off Boeing's
production line, looks fairly normal-until you spot a giant bracket on the side
of the fuselage where an optional third engine can be mounted. That pylon isn't
for redundancy or extra power, though: it's for field-testing new jet engines.
Stepping inside the airplane, which is owned by multinational conglomerate
Honeywell, things get even cooler: to the left is an open cockpit with two
softly-spoken American pilots, and to the right there are 10 ageing leather
seats. And then, behind the seats... there's a 1980s-era science lab.
There is no plastic cladding, nor overhead bins. There's insulation, of course,
so that you don't freeze to death, but in a few places you can see and touch
the three millimetres of aluminium that make up the airplane's hull. There are
the usual windows, and the space feels a lot lighter than a normal passenger
jet. Miles of neatly ducted, shielded cables run along the ceiling. A big steel
box on the floor contains the emergency oxygen supply. A number of large
cabinets contain diagnostic equipment for the third engine mount (which sadly
isn't equipped today).
Heading deeper into the aircraft there are a bunch of terminals: large metal
enclosures that can be outfitted with whatever equipment is required for the
flight. In front of each terminal is an engineer or technician who is poking
around on a keyboard or fiddling with some switches; chunky switches that take
me straight back to electronics class at school 25 years ago. I was on the
plane to try out a specific technology, but most of the terminals were being
used to test other Honeywell prototypes. It's mighty expensive to crew and fly
a 757, after all-Honeywell wants to make the most of every flight.
After a while there aren't even any terminals: there's just empty space and
random detritus on the ground, like a 24-pack of water bottles. The back wall
is padded, presumably to stop any unstowed objects from crashing out of the
tailplane. After taking a few selfies, I wander back up the aisle to check out
the star of the show: Inmarsat's new Global Xpress satellite Internet service.
Just outside the airplane, beneath a plastic fairing, is an arrow antenna that
follows one of Inmarsat's four geostationary Global Xpress (aka I-5)
satellites. The I-5 constellation consists of three satellites that provide
almost unbroken global coverage, and a recently launched fourth satellite that
provides extra coverage (i.e. bandwidth) over Asia. Each satellite produces 89
discrete Ka-band (20-30GHz) spot beams that users can latch onto. Spots have
their own dedicated wedge of spectrum and bandwidth, to reduce interference and
congestion.
As the 757 banks and turns, the antenna moves so that it always points at the
satellite. If the airplane crosses from one coverage area into another (in the
middle of the Pacific or Atlantic, for example), the antenna quickly whips over
to a new set of coordinates. It still takes about 45 seconds to renegotiate a
connection with the new satellite, though. (I asked an Inmarsat engineer why it
takes that long; he wasn't sure, and suggested it was something they could
probably improve on.)
In the case of GX Aviation (the name of the product used by aircraft to connect
to the Global Xpress satellites) each end point has access to 50Mbps of
downstream bandwidth and 1Mbps upload (sending data to a satellite is still
really painful). In practice, as my plane buzzed by Colchester and headed
towards Norwich, I got around 30Mbps, which is enough to stream Netflix or
scroll through your video-infested Facebook feed. Latency was about 600ms:
exactly what you'd expect when bouncing packets via a satellite 22,000 miles
away. Facetime and Skype worked okay on my end-I saw a lovely, smooth image on
my phone-but a friend, sitting in an office in London, definitely felt my
limited upstream bandwidth: the image stopped and started, and I looked jpeggy.
50Mbps is a massive improvement over other contemporaneous satellite Internet
products, which range from about 300Kbps to 3Mbps. But if you tell 200
passengers that they can all stream Netflix while over the Atlantic... well,
you can probably guess how that will go. You could restrict access to the local
Wi-Fi network-perhaps only business-class passengers can stream Netflix-but
only real solution is boosting the link speed between satellite and aircraft.
An Inmarsat engineer says that downlink speeds of 300Mbps would be possible
with a high-gain antenna, but they don't yet have the technology to whack a
giant parabolic dish on top of an object hurtling through the air at 500mph.
20 airlines have signed up for GX Aviation so far, and Inmarsat says that 1,200
aircraft will soon be equipped with 50Mbps satellite Internet access.
Honeywell, which manufactures just about every piece of aerospace equipment you
can imagine, including the satcom terminals used by most planes in the sky
today, avionics, and jet engines, has a vested interest in GX Aviation: they've
just rolled out a bunch of new Internet-connected apps for pilots. There's a
real-time weather app that helps the captain make strategic decisions to avoid
turbulence, and Flight Bag, which lets flight crew plot more efficient courses,
saving time, money, and fuel.
Inmarsat plans to launch a fifth Global Xpress satellite in the next few
years-which will probably coincide with the first satellites of SpaceX's
low-altitude constellation. Last week, an Ariane 5 rocket launched an S-band
satellite that plays a key role in Inmarsat's high-speed European Aviation
Network-which will offer 4G-like connectivity for aircraft, but only over
European airspace. We'll have more on EAN at a later date.
This post originated on Ars Technica UK
----------------------------------------------------------------------
You can UNSUBSCRIBE from the OpenDTV list in two ways:
- Using the UNSUBSCRIBE command in your user configuration settings at
FreeLists.org
- By sending a message to: opendtv-request@xxxxxxxxxxxxx with the word
unsubscribe in the subject line.
