Fifty years ago, at the height of the Vietnam War, the land around Mineral Wells, Texas, was dotted with stagefields used for training U.S. Army helicopter pilots out of Fort Wolters.
On Monday, a few dozen observers gathered at one of these old airstrips to witness a different form of vertical flight — an autonomous demonstration of Bell’s new cargo drone, the Autonomous Pod Transport (APT) 70.
The all-electric APT 70 is one of a scalable family of autonomous aircraft that Bell is developing for missions including package delivery, critical medical transport, and disaster relief. Bell is collaborating on the project with the Japanese third-party logistics provider Yamato, which was also present in Mineral Wells to demonstrate its detachable wheeled attachment for the vehicle: the Pod Unit for Parcel Air-transportation (PUPA), sized for packages up to 70 pounds (31 kilograms).
Shortly after 9 a.m. on the characteristically hot August morning, the six-foot-tall tail-sitting biplane lifted vertically into the air, then rotated into forward flight. Autonomously following pre-programmed waypoints, it made two circuits of the field at a height of around 175 feet before returning to its starting point and performing a slow vertical landing. In “airplane mode,” the vehicle was remarkably quiet. It was considerably noisier in VTOL mode, sounding like a hive of angry bees as its four gimbaled rotors worked to steady it in winds gusting to about 20 knots.
Although Bell had planned on performing only a single demonstration flight, it repeated the demo around 30 minutes later for the benefit of some late-arriving guests. Once again, despite the brisk winds, the APT made two laps of the field before returning to its starting point uneventfully. According to APT program manager John Wittmaak, the APT 70 will have a top speed above 110 knots. Range and endurance will vary based on loading and environmental conditions, but should be around 35 miles (56 kilometers) with a 70-lb. payload.
The location of the demo was richly symbolic for Bell, which last year dropped the word “Helicopter” from its name to better reflect its identity as a “technology company redefining flight,” according to CEO Mitch Snyder. Once best known for iconic helicopter models like the OH-13 flown by students at Fort Wolters — and the UH-1 Huey that many of them would later fly in Vietnam — Bell has been aggressively expanding its portfolio of vertical flight technologies to include its new generation military tiltrotor, the V-280 Valor, and a hybrid electric air taxi, the Bell Nexus.
Bell’s work on APT will position the company to take advantage of cargo delivery opportunities both in the commercial market, with customers like Yamato, and in the military space. More generally, it will help Bell prepare for a future in which autonomous flights through busy urban airspace are routine, whether those flights are carrying passengers or cargo.
Specifically, Bell is using the APT 70 for its participation in NASA’s Systems Integration and Operationalization (SIO) demonstration activity, which aims to help integrate unmanned aircraft systems into the national airspace system. Around the middle of next year, Bell plans to fly the APT 70 beyond visual line of sight through the Dallas-Fort Worth (DFW) metropolitan area, including the busy airspace surrounding its major airports.
“We are going to fly through Class B airspace in the DFW metroplex, with a 315-pound vehicle,” emphasized Bell VP of Innovation Scott Drennan at the Monday event. “That’s a big deal. That’s a vehicle that’s operational, usable, and of a size that can help real customers.”
According to Wittmaak, for that demonstration the APT 70 will be equipped with a variety of sensors and navigation systems, including radar, ADS-B, dual inertial navigation systems, primary and backup GPS systems, and computer vision systems. Bell is partnering with Xwing for detect-and-avoid technologies, and CASA for weather avoidance technology.
Although that demonstration will advance the APT’s autonomous capabilities even further, it will have a human overseeing it, and Drennan expects that humans will monitor the aircraft once they’re deployed commercially, too.
“I think the smartest approach initially will be an operator with multiple aircraft. And think of the operator in that case not so much as a hands-on-the-stick kind type pilot, but a monitor of the system,” he said.
“At Bell we often talk about autonomy as a new interface between man and machine,” Drennan continued. “We want to say, ‘Oh my goodness, these vehicles just get up and do their own thing; they have behavioral characteristics.’ But it’s really just a new kind of partnership between man and machine, with more of the burden heading toward the machine, but the man still in the loop.”