Change in the world of aviation is not just in the air. It is also on the ground. Surface operations of large aircraft have long been targeted as ripe for savings, as jet engines optimised for cruising at 35,000 feet are hardly at their most efficient propelling tonnes of metal along airport taxiways.
The aviation industry is not the world’s biggest pollution villain but the sector’s high profile, along with the cost of oil and continued pressure on airline bottom lines, are lending extra thrust to alternative sources of power for moving aircraft on the ground.
Frost & Sullivan, a consultancy, recently cast the spotlight on two offerings from leading aerospace companies on display at the Paris Air Show in June. Alix Leboulanger, the consultancy's aerospace and defence analyst, said Safran and Honeywell's Electric Green Taxiing System (EGTS) prototype "could fundamentally change aircraft taxi out process by enabling the airplane to go autonomously from the airport gate till the runaway without the need to engage the aircraft main engines".
The consultancy said another system intended to make airport operations greener and aircraft more environmental friendly was the TaxiBot vehicle, jointly developed by Israel Aerospace Industries, Airbus, ground support equipment specialist TLD Group and Lufthansa.
The EGTS solution places electric motors at the aircraft’s wheels, using power generated by the plane’s own auxiliary power unit – which is intended to be at its most efficient while supplying power for aircraft while on the ground.
According to Safran, the system could save airlines “several hundred thousand dollars per aircraft per year”, cutting total fuel consumption by 4 per cent and of course trimming back emissions, and noise, at the same time.
The TaxiBot, a pilot-controlled diesel-electric hybrid tug, does not offer the same autonomy to aircraft, but would similarly mean that a jet aircraft’s main engines could be shut down for ground manoeuvring – without any weight penalty for the aircraft itself.
While neither the EGTS nor the TaxiBot sidestep emissions problems entirely, they are a push in the right direction. Frost & Sullivan develops the theme further, saying that the acceptance of such innovation helps build the case, and the expertise, for all-electric aircraft.
Pointing to prototypes such as the electric-powered, tilting-rotor, helicopter-cum-airplane Project Zero from Italian manufacturer AgustaWestland, the consultancy says there is the potential for leapfrogging change.
“All-electric commercial aviation could take off by 2035-2040,” says Ms Leboulanger. “Therefore, it is the right time to start thinking of new electric infrastructures for airports.”
Much of the pressure of conservatism that has held back innovation in the aviation industry has come from regulators. As the saga over the Dreamliner's new battery demonstrated, they are concerned with minimising risk and therefore tend to be wary of change, at least in civil aviation.
Carbon fibre
It is ironic that carbon fibre, which took off in military and experimental aircraft, should have been almost casually accepted in the world of Formula One car racing, and nearly the norm in high-end road cars, before circling back to aviation in its use for the structures of the latest Boeing and Airbus airliners.
However, it is not just lightning-strike resistance, material longevity and assurance on stress paths that have been factors here. Repair organisations highly adept at working with aluminium alloy also questioned whether minor damage could be fixed safely without a huge weight gain – or without junking significant components such as entire fuselages.
Those fears are now in the past, as experience has grown in working with such "new" materials. Also moving into the past, it seems, is some of the more restrictive hand of regulation. After some troubling times when European regulation was being harmonised under a European Aviation Safety Agency, regulators on either side of the Atlantic have been surprising plane makers by taking steps to accept each other's findings. That easing of duplication has already saved millions of dollars in the cost of satisfying the authorities on safety.
Another step in a positive direction came in July when the US House of Representatives passed the Small Airplane Revitalisation Act, intended to make certifying some general aviation aircraft simpler. The Federal Aviation Administration is keen to cut the cost of certification, while at the same time driving up safety standards. If the legislation completes its way through the US process, and similar rule changes follow, that would also make it easier for manufacturers to introduce new technologies. The multitude of ideas, fanciful and otherwise, for small, light aircraft with electric motors shows that pressure for improving the efficiency of aircraft is plentiful at both the heavy and the lighter end of the industry. And that, given the current state of progress in the technology of batteries and electric motors, is where the future may arrive first.
Copyright The Financial Times Limited 2013
