Sikorsky and Lockheed Martin gained widespread attention this month after successful test flights of a helicopter with no one on board as the aircraft traversed an aerial path simulating Manhattan’s urban canyons of high rises.
The next big thing for Sikorsky Innovations? A helicopter that would barely be noticed with just the chop of its rotor blades to announce its arrival and no echoing roar of turbine engines.
In its demonstration this month of a helicopter with computers and sensors to execute pinpoint landings and complex flight routes with no pilot, Sikorsky gave only passing mention to another initiative gathering momentum at its Connecticut headquarters.
At its Stratford facility, Sikorsky is developing helicopters equipped with light electric motors with the power and running time to replace heavy, fuel-burning engines.
In November, Sikorsky and parent Lockheed Martin won their latest U.S. patent for an electric drive capable of delivering the power needed to lift a medium-sized helicopter like a Sikorsky Black Hawk or S-76, and maintain flight for an extended stretch. Sikorsky has received a number of patents since 2008 on varying iterations of the technology.
Proponents of electric helicopters maintain that those aircraft will be safer and cheaper to maintain, with far fewer parts exposed to wear and tear like gear boxes and transmissions.
“Don’t just think military — we are looking across all markets, military and civil,” Igor Cherepinsky, head of Sikorsky Innovations, said in an interview with Hearst Connecticut Media Group. “Being able to quietly land in Manhattan without the noise may mean acceptance of helicopters a lot more than now.”
Cherepinsky offered no timeline for when Sikorsky might debut a “demonstrator” helicopter to test the capabilities of electric-powered flight, but said the manufacturer is actively developing the concept. The company is doing so even as a Department of Defense decision looms on an eventual replacement for the Black Hawk helicopter, which could set Sikorsky up for decades of Pentagon contracts.
A dozen years ago, Sikorsky brought a working, all-electric helicopter to an Experimental Aircraft Association show in Wisconsin. The Sikorsky Firefly could stay aloft for only 15 minutes, and with room for just the pilot to allow for the big lithium-ion batteries from which it drew electricity.
But Sikorsky is now in catch-up mode. In California, Joby Aviation has already completed more than 1,000 test flights of a tilt-rotor electric aircraft, having received an “airworthiness” certificate from the U.S. Air Force and seeking one from the Federal Aviation Administration.
On Wednesday, one of Joby Aviation’s two prototypes crashed during a flight test. The company has not released details on what went wrong, but the pilot was reported to not be injured. It remains unclear whether an investigation into the crash will cause a delay in the FAA certification process.
In a statement, Joby Aviation said safety is a “core value” for the company.
“Experimental flight test programs are intentionally designed to determine the limits of aircraft performance, and accidents are unfortunately a possibility,” the company stated. “We will be supporting the relevant authorities in investigating the accident thoroughly.”
During a November conference call with investment analysts, Joby Aviation CEO JoeBen Bevirt emphasized the safety of the S4 spanning the aircraft itself as well as the batteries that supply it power.
Powered by six sets of blades, the Joby Aviation S4 can lift a helicopter then tilt its rotors forward to fly like an airplane. In a flight test last year, a pilot flew the aircraft 150 miles in just over an hour and a quarter.
Backed initially by Toyota and Uber Technologies, Joby Aviation is focusing on what it believes will be an emerging market for “air taxi” service between cities and airports and other destinations.
In November, Bevirt described the company’s rotor blades as “less wop-wop and more like the wind in the trees.”
The company has posted a video online measuring the decibel differential of the S4 versus several other aircraft as they fly overhead, including a Leonardo helicopter similar in size to the Sikorsky S-76.
“We believe in taking on challenges that others shy away from — we approach them without any preconceived ideas and we work hard and fast to solve them,” Bevirt said in November. “Delivering an aircraft with a low noise footprint is fundamental to bringing our service closer to where customers want it.”
Plenty of others are working toward the same goal. Heading into last year, the Vertical Flight Society tracked nearly 200 companies or designers working on electric aircraft that can take off and land like a helicopter.
One is Bell, a subsidiary of Rhode Island-based Textron, which pioneered tilt-rotor technology with the V-22 Osprey for the U.S. military. The past three years, Bell has been teasing a tilt-rotor aircraft helicopter that has six sets of blades, but configured like those in the fictional aircraft depicted in the movie “Avatar.”
Airbus is floating what it calls a “multicopter” that can take off vertically. And Boeing has flown an electric aircraft designed by subsidiary Aurora Flight Sciences.
For those accustomed already to the quiet ride of electric vehicles, the benefits in everyday aviation are self-evident in a drastic reduction of noise near heliports.
But for the military — Sikorsky’s primary customer — a quiet helicopter has major implications as well when it comes to surveillance in hostile territory, or dropping off commando troops without detection.
Couple electric power with the autonomous flight capabilities Sikorsky demonstrated this month, and Cherepinsky says a new generation of helicopters is on the horizon that will be far safer to operate in city environments, far quieter and with other advantages as well.
“Aircraft with electric propulsion are cheaper and they’re greener, so it makes economic sense and it makes environmental sense,” Cherepinsky said. “But the reason why we are doing all this is — first and foremost — safety. We want to dramatically improve the safety of rotor craft.”