Cargo eVTOL Matures
TVF 2020 covered the use of electric VTOL technology for goods as well as people.
By Kenneth I. Swartz
The Transformative Vertical Flight 2020 event in San Jose, California, in mid-January, featured a wide range of sessions and panel discussions that covered the breadth and depth of electric vertical takeoff and landing (eVTOL) progress and capabilities (see “Transformative Vertical Flight 2020,” pg. 38). One such panel covered the use of eVTOL technology for cargo.
eVTOL Cargo Delivery Panel
The drone package delivery market is projected to grow from $2.1B in 2023 to $27.4B in 2030 — a compound annual growth rate (CAGR) of 45% — explained Ajay Sehgal, the chief engineer at KBR, citing a December 2019 report by MarketsandMarkets.com.
The number of companies active in the eVTOL cargo delivery sector continues to grow and includes everything from global aerospace and logistics companies like Airbus and Boeing (Aurora), Amazon Prime, DHL, UPS, UberEats and dozens of eVTOL startups (see the VFS website www.eVTOL.news).
The eVTOL cargo industry will require its own ecosystem that includes technology, regulatory, infrastructure, operations and public acceptance challenges, many of which overlap with the ecosystem required to fly passengers.
Bell sees its cargo drone service starting in remote and rural operations with limited initial deployment, providing services for time-sensitive and vital cargo in areas where manned aviation may be cost-prohibitive or even limited in capability, said Nicholas Brodeur, a Bell Canada engineer working on the Bell Autonomous Pod Transport (APT).
Yu Ito, chief R&D specialist on eVTOL Projects at Yamato Holdings Co., Ltd., said that eVTOL aircraft would provide a better customer experience by shortening lead times and easing shipping and receiving. The collaboration between Bell and Yamato will see Bell develop an unmanned cargo eVTOL aircraft and Yamato create a detachable Pod Unit for Parcel Air-transportation (PUPA), with the goal of starting service in 2025.
The Elroy Air Chaparral is an autonomous cargo eVTOL capable of transporting 300 lb (112 kg) of cargo 300 miles (480 km) for middle-mile logistics. David Merrill, CEO of Elroy Air, expects the Chaparral to provide faster delivery speeds than ground transport, lower operating costs than manned aircraft, better fuel efficiency than existing aircraft and the ability to serve more destinations than fixed-wing aircraft. The 1,215 lb (453 kg) cargo drone made its first hover on Aug. 14, 2019, at Camp Roberts in central California. The test site is convenient for drone testing because the airspace is not controlled by the US Federal Aviation Administration (FAA), Merrill said.
The United Parcel Service began its drone evaluations in 2016 working with Zipline, a California-based robotics company, to use fixed-wing drones to deliver critically needed blood to medical centers in rural Rwanda and Ghana over a three-year period. The same year, UPS staged a mock delivery of urgently needed medicine from Beverly, Massachusetts, to an island 3 miles (5 km) off the Atlantic coast.
The following year, the company simulated routine package delivery in Tampa, Florida, in which an electric Workhorse HorseFly drone was launched from a Workhorse prototype hybrid-electric UPS package truck, made a delivery and returned to the delivery vehicle on its route. This was followed by the launch of a pilot program in March 2019, which sees UPS using a Matternet M2 quadcopter to transport medical samples or specimens around WakeMed’s flagship hospital and campus in Raleigh, North Carolina. This was one of the FAA’s drone integration pilot programs.
More recently, UPS announced it is also introducing drone delivery service at the University of Utah Health campus in Salt Lake City, which will be flown by UPS’s drone airline subsidiary, UPS Flight Forward, which received the FAA’s first Part 135 Standard certification last September.
Bruno Mombrinie described the Metro Hop all-electric, short takeoff and landing (eSTOL) airplane his company is developing to transport high-demand medical supplies in metropolitan areas. Metro Hop engineers are from the University of Stuttgart e-Genius team.
The aircraft has a payload of 1,000 lb (450 kg) and a 108 nm (200 km) range and features an active spring-loaded landing gear that allows the plane to cruise at 220 kt (407 km/h) and takeoff and land in 200 ft (60 m). The eSTOL performance will allow the aircraft to operate from short runways adjacent to or on the roofs of large pharmaceutical and medical supply distribution centers. Metro Hop could also land at urban eSTOL ports built on the roofs of hospital complexes to unload high-value medical supplies.
Metro Hop plans its aircraft to be piloted, with automatically loaded and unloaded cargo containers. Once proven out and the regulations permit it, Mombrinie said the eSTOL aircraft could provide air taxi services.
Sabrewing Aircraft Company
As part of a separate session, “eVTOL Industry Updates,” Ed De Reyes, co-founder and CEO of Sabrewing Aircraft Company of Camarillo, California, described the design, development and mission of the hybrid-electric Rhaegal RG-1 cargo air vehicle, which he said would be the world’s first heavy-lift, long-range autonomous eVTOL cargo aircraft. Named after a medieval dragon (not from the “Game of Thrones” television series), the aircraft will be produced in two sizes to fulfill a wide range of civil and military logistics missions.
About six years ago, De Reyes and co-founder Oliver Garrow set out to develop an unmanned electric-powered cargo aircraft with VTOL capability that had lower acquisition and direct operating costs than a helicopter or twin turboprop airplane and could be certified under the then-proposed revision to Federal Aviation Regulations (FAR) Part 23 (Amendment 64 went into effect in August 2017).
De Reyes spent most of his career working as an aerospace engineer, experimental test pilot and flight test engineer on various civil and military certification programs for companies such as McDonnell Douglas, General Dynamics, Northrop Grumman, Cobalt Aircraft, Elytron and Moller International.
De Reyes said the aircraft configuration was influenced by his earlier work as an engineer and test pilot on the Moller 400 VTOL “flying car” and the remotely commanded design incorporates lessons learned working on the Northrop Grumman Global Hawk. “We’re flying this aircraft in exactly the same way the Global Hawk is being flown in FAA air space,” said De Reyes, which allows the operating weight to be greater than the 1,320 lb (600 kg) restriction currently applied to unmanned aircraft.
He and his wife also owned a small Part 135 air cargo airline with a Cessna 421, which gave him plenty of first-hand operations experience delivering packages and freight, as well as flying in poor weather.
The first test aircraft is being assembled at Hayward Airport in the San Francisco Bay area and is 28-ft (8.56-m) long and has four ducted electric fans mounted at the “four corners” of the aircraft. Rhaegal is designed to fly a 1,000 lb (454 kg) payload about 1,000 nm (1,850 km) at a cruise speed of 180 kt (330 km/h) and will be powered by a turbo-electric engine with a 700-shp (522-kW) Rolls-Royce M250-C47E turboshaft driving a generator.
The sections of FAR Part 23 related to passenger safety are not applicable to unmanned aircraft and since the hybrid engine directly powers the fans without a battery pack, this sidesteps any issues regarding battery certification, helps keep the aircraft empty weight low and doesn’t restrict operations in extremely cold temperatures.
The production aircraft is a nearly twice as large, with a 49-ft (8.56-m) fuselage and 51-ft (13.8-m) wing. It features a front-loading cargo hold designed to accommodate standard airline lower deck cargo containers (e.g. a single LD1 or LD2, or two LD3s) with a ramp and winch to ease loading.
Remote fly-in communities in Alaska were the first to take an interest in the Rhaegal cargo aircraft, since air freight fees have a direct impact on cost of living, including the price of food. Sabrewing has received $51 million in orders, including a $41 million launch customer order for 10 aircraft from the Aleut Community of St. Paul Island, located some 310 miles (500 km) southwest of the Alaskan mainland (the island is due south of the easternmost point of Russia).
Poor weather, including fog and cross winds, routinely disrupts food and freight shipments to St. Paul Island. The aircraft will be equipped with a deicing system to permit flights into known icing and have the altitude performance to fly over bad weather. The VTOL aircraft also will be able to land in remote areas and operate from runways closed by cross winds. Other features will include an anti-collision system, a fully autonomous detect-and-avoid system for Class B & C airspace, and quadruple-redundant satellite command, control and communication.
The Aleut Community of St. Paul Island is also partnering with Sabrewing to establish a UAS test range over the Bering Sea.
De Reyes said the demonstrator airframe would be complete by the end of January and Rhaegal was expected to fly in early 2020, with a service entry in 2021.
SkyDrive (established in Japan in July 2018) represents the commercialization of the volunteer Cartivator flying car project (originally launched in 2012) and has secured the support of more than 30 sponsors from the Japanese aerospace, automotive and industrial sector. National and local governments are also supporting the program, which has raised about $20M to date.
The company’s goal is to develop a compact eVTOL aircraft than weighs about 1,100 lb (500 kg), can carry one or two passengers and fly a maximum distance of 31 miles (50 km). The quadcopter design features pairs of 5-ft (1.5-m) diameter coaxial fixed-pitched rotors in each quadrant.
Manned demonstration flights of a single-seat proof of concept aircraft weighting about 661 lb (300 kg) with a 167-lb (80-kg) pilot is expected in the first half of 2020 at two test sites in Toyota City and then the aircraft is scheduled to fly in public for the first time at Tokyo’s Haneda Airport in August. The first sales release is scheduled for 2023, with mass production commencing in 2026 for the leisure/commuter market.
The development initially utilized systems from the hobby drone market, but the company has now transitioned to the development of certifiable systems. In parallel, SkyDrive is also developing a cargo drone — with payloads of more than 220 lb (100 kg) — leveraging the same technologies. Initial sales will be to niche operations, followed by compliance with new Japan Civil Aviation Bureau (JCAB) regulations, in about 2022.
UAM for Cargo
Electric VTOL is an enabling technology for distributed electric propulsion and other novel aircraft configurations, and for the most part, it is payload agnostic. NASA’s definition of Urban Air Mobility (UAM) is “safe and efficient air traffic operations in a metropolitan area for manned aircraft and unmanned aircraft systems.”
In some respects, cargo delivery — especially in less populated areas — is a much safer means to develop eVTOL technology. Air taxi service is one of the most safety-critical missions possible, with the public perception of safety being paramount. But the higher population density and income in urban centers promises sufficient demand to generate high passenger load factors and revenue yields that air taxi services would eventually pay off.
The safety and reliability of manned eVTOL aircraft could be greatly augmented by cargo and other unmanned delivery services.