Solar Impulse shows even narrowband IoT benefits

MONACO — Inside the Solar Impulse control centre, it’s clear that live streaming of inflight data is key to this remarkable feat of aviation — and human — achievement. Much of the information generated on board is transmitted to and processed in Solar Impulse’s Monaco Control Center before, in some cases, being transmitted back to the Solar Impulse 2 aircraft. It’s a fully connected aircraft demonstrating the real world uses of the Internet of Things, in real-time, with real people and a real aircraft.

Enabling the IoT on board is the same Inmarsat SwiftBroadband (SBB) L-band service currently used on numerous commercial aircraft worldwide, provided by SITAONAIR via Cobham hardware more frequently seen in business aviation.

“We see it as an airborne technology lab, pioneering the connected aircraft technology for the commercial airline industry. We think this is what the connected aircraft will look like in the future,” suggests SITAONAIR spokesperson Aurélie Giles to Runway Girl Network. “SITAONAIR has been a strategic partner for Solar Impulse since the early days of the project in 2010, helping the aircraft become the first in the world to offer full nose-to-tail connectivity. Solar Impulse is an ideal shop window for the connected aircraft that SITAONAIR endorses for its commercial airline customers.”

kontron newest“These Internet of Things data flows will enable real-time decision making and optimization, enabling data and information to flow uplink to the aircraft and the flight deck to trigger appropriate actions and changes, either through the pilot and crew, or directly with the aircraft. This secure return loop is fundamental to realizing the full benefit of the connected aircraft,” adds SITAONAIR’s chief technology officer Greg Ouillon, and indeed that’s true for Solar Impulse, even over a relatively low-capacity system in modern terms.

“The system deployed on Solar Impulse 2 is composed of a specially customized Cobham SATCOM AVIATOR 300SP (Special Purpose) system providing data and voice connectivity,” SITAONAIR’s Giles explains. “It is a modified, 40 per cent weight-reduced SBB system, including IGA-5006 antenna, Satellite Data Unit (SDU) and combined High Power Amplifier, Diplexer, and Low Noise Amplifier (HLD).”

The adapted single-channel intermediate gain antenna system maxes out at 332kbps, according to Cobham, which calls it the “a complete voice and data solution for Corporate, Military, Government & Special Missions applications”. SITAONAIR’s Giles says “the Cobham SATCOM AVIATOR 300SP (Special Purpose) together with the IGA-5006, offers uplink (ground to air) SwiftBroadband capacity between 200 and 344 Kbps, and downlink (air to ground) SwiftBroadband capacity between 192 to 332 Kbps.”

What’s remarkable is the amount of data — which is turned into useful aircraft intelligence that can be acted upon — coming trickling through a system that is neither particularly swift nor, by any modern definition, broadband. Solar Impulse’s team was keen to propose inflight interviews with the pilots, but it’s clear from the Skype-enabled live conversation between pilot Bertrand Piccard and United Nations Secretary-General Ban Ki-moon that this system demonstrates significant lag.

Solar Impulse's Monaco Control Center analyses and acts on a huge number of data points. Image: John Walton

Solar Impulse’s Monaco Control Center analyses and acts on a huge number of data points. Image: John Walton

It takes ten seconds after a brief pause by the speaker at 11m51s for Piccard’s voice noting that the voice of the speaker has stopped to be heard on the audio, for example. The one-way connection takes quite some time to be established at 14m20s onwards, and despite the amusement Star Trek aficionados will surely get at listening to the UN Secretary-General call “Captain Piccard” over a satellite connection, the video from Solar Impulse is more stop-motion than smooth and the audio is (perhaps unsurprisingly) reminiscent of satellite telephony from the 1990s.

Yet even a system with these clear limitations can drive useful, applicable aircraft information. Most impressive, however, is the way in which Solar Impulse demonstrates how designing connectivity systems to pass even relatively small volumes of data to an operations centre like the one in Monaco can drive efficiency.

SITAONAIR’s estimates suggest that the entire round-the-world mission will generate just 400MB of live video and 4GB of photographs from the aircraft. For the amount of time this aircraft, slower than a motorcycle, will be in the air, that’s remarkably low.

As an example, Skype — which Solar Impulse was using, at least on the ground, to enable communication between Bertrand Piccard and Ban Ki-moon — suggests that it requires a minimum of 128kbps up and down, with a recommended 300 kbps, for non-high-quality video.

As a passenger platform, what SITAONAIR and Inmarsat’s SwiftBroadband are offering is two to four times that connection. As a technology demonstrator for safety services, particularly given the current preference for creating an air gap between flight deck and cabin connectivity, Solar Impulse is a good shop window for this satellite system.

Inmarsat recently insisted that L-band communications continue to perform well for an entire cabin on commercial aircraft. But a system that provides enough bandwidth for one person to do what is essentially audio plus stills, in addition to a trickle of well-designed data is not widely useful for passengers.

It’s truly amazing that Solar Impulse can operate, let alone communicate via video (no matter how low-res), entirely by solar power. But it will be fascinating to look back at a future Solar Impulse — flying faster, with fewer stops, and communicating with truly high-speed Internet.

Solar Impulse's circumnavigation will require zero onboard fuel, but much expertise. Image: Solar Impulse

Solar Impulse’s circumnavigation will require zero onboard fuel, but much expertise. Image: Solar Impulse

John Walton was a guest of SITAONAIR at the Solar Impulse Monaco Control Center