Gogo Eyes More Trial Airlines with ThinKom’s Antenna

 In ThinAir

Gogo has tapped British manufacturer Cobham to supply the radome for its new 2Ku inflight connectivity solution, as the Chicago-based company advances its plan for delivering 2Ku to airlines around the globe.

The company first unveiled 2Ku in April at the Aircraft Interiors Expo, and recently snagged Aeromexico and Virgin Atlantic as 2Ku customers, and United Airlines as a trial airline. Management tells RGN that it evaluated “multiple vendors” for the radome, which will house the two low-profile ThinKom-made mechanically steered antennas that will serve as the core of 2Ku.

Referencing Gogo’s request for proposals for the 2Ku radome, executive VP and chief technology officer Anand Chari said the company carefully studied the different designs and their capabilities “and we liked what Cobham had to offer”. He acknowledges that, all-in, the 2Ku system will be heavier than traditional Ku. “So it’s heavier, but then the drag is lower, so the drag equivalent weight is much lower than competing solutions.”

Gogo spokesman Steve Nolan explains: “The 2Ku system weight is approximately 350 lbs and includes the Tx and Rx antennas, modem, antenna control unit, RF unit, radome, ring and adapter plate. Compared to gimbaled systems on the same basis, we believe it weighs around 50 lbs. more. However, when you take drag into account, its effective weight on the aircraft is significantly lighter.”

Drilling down further, Gogo VP of airborne access Sean Cordone explained to us that the black rim around the ThinKom antenna is simply the aluminum housing that serves to protect the antenna. Pointing to the red disks, Cordone says, “The radiating structure you see here – this is a polarizer; there are four such disks inside [each] antenna. The unique combination of them determines where the beam is synthesized.

“It’s really a fundamentally new way to do an antenna. We don’t direct a beam in a specific location, instead we actually synthesize the beam in the direction we want it to go. And it’s all done through the physics of the way these four disks align.”

Are they spinning? “They don’t need to spin unless the aircraft orientation changes,” says Cordone. “So for a given orientation of the four disks, a beam will be synthesized in a fixed direction. So the novelty here is that, as the aircraft moves, each of these disks also move and you can see that although they’re large in diameter, there is very little mass so you’re able to move them very quickly. So they have a big advantage, relative to those large mechanical structures that have to move in two dimensions.”

A separate, yet important, benefit of 2Ku is its ability to operate efficiently close to the equator, according to Gogo. “You’re familiar with the asymmetric apertures that are conventionally used. The asymmetric aperture causes an issue with what’s called skew angles, so when you’re at high skew angles, the beam is elongated in elevation and that’s projected in the geoplane and from a regulatory perspective, you’re required to lower the power, and lowering power lowers the efficiency,” says Cordone.

To put it in simpler terms, adds Chari, “When you’re near the equator, this [2Ku] can produce a narrower beam and not cause energy to spill into the adjacent satellite. The performance degradation is dramatic with the current rectangularly shaped antennas; they degrade in performance. This [2Ku] is the opposite and almost improves in performance, making the delta – the gap – even bigger [when compared with traditional Ku].”

It wasn’t so very long ago that Gogo saw Ku as an interim solution – something to bridge the gap until Inmarsat’s Global Xpress Ka-band service is available in 2015. These days, however, it’s clear that Gogo is putting more and more proverbial eggs in the Ku basket. The company suggests that while 2Ku is capable of 70mbps speeds over current Ku satellites, it will support speeds of over 100mbps when the next generation of high throughput (HTS) satellites are launched.

Naturally, Gogo’s shift in focus begs the question: is Gogo still committed to GX? Or, for that matter, is Inmarsat still committed to Gogo as a service distribution partner? Referring to Gogo’s position as a GX distribution partner, Gogo CEO Michael Small says, “We would like to keep it intact. We sell a whole suite of products. We still sell Iridium. We still sell SwiftBroadband … so there are different aircraft that need different things, and fly different things.”

When it comes to GX, says Small, 2Ku is “going to be competitive. Technology changes fast in this business, and as we said, we’ll buy it from anybody; we’ll make it ourselves; and we owe it to our airline partners to get the best solutions from them and we’ll keep looking.”

Chari suggests that more US carriers will “absolutely” give careful consideration to adopting 2Ku, “specifically if they have fleets with Caribbean routes, Hawaii or South America routes, so any overwater mission, [2Ku], is a great application for those as well.” At present, it looks like United will be the first to take the leap, when it trials 2Ku late next year on five Boeing 757s flying p.s. transcontinental service. But what about Gogo’s largest airline customer, Delta? Chari says he thinks the airline will consider 2Ku, noting, “I think it’s technology [that’s] available and useful to everybody out there.”

That includes Japan Airlines (JAL), which has agreed to trial 2Ku, though JAL hasn’t defined what aircraft type will test 2Ku.

Gogo is already installing its traditional Ku system – with an Astronics/Aerosat-made antenna and St. Gobain radome – on JAL domestic aircraft, while Panasonic Avionics is installing its eXConnect Ku system on JAL’s international fleet. Asked by RGN if Gogo has an opportunity to snatch some of the international Ku equipage business already secured by Panasonic, Small says, “I’m making no additional comment other than [that] they expect to be among the first to trial this.”

The Gogo CEO says 2Ku won’t suffer the same sort of bird strike problems that has stalled equipage of traditional Ku on Delta and other carriers. “It is lower profile so probability of bird strike will go way down. The [Cobham radome] should A) deflect and B) not be very penetrable by a bird anyways.”

Gogo, which holds an exclusive agreement with ThinKom for the antenna, aims to secure supplemental type certification (STC) on its first aircraft type for 2Ku next year.

 

Original article published on RGN.

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