The aerospace industry is one of many being impacted by electrification. While not yet affecting consumers directly, there have been demonstrators of battery electric airplanes and eVTOLs in the industry that show that air travel can be more convenient and more sustainable.
With well-funded start-ups and industry stalwarts Boeing and Airbus investing in electric aircraft technology and programs, it's interesting to think about what the future holds for electric aircraft and eVTOL. First, let's examine what eVTOL truly means and what beneficial features are powering electric aircraft.
What is eVTOL and What does eVTOL Stand For?
There are two primary categories of electric aircraft — traditional airplanes that takeoff from a runway and vertical takeoff and landing (VTOL) aircraft. As suggested, eVTOL stands for electric vertical takeoff and landing. Electric motors bring the critical performance factors needed for the propulsion of both types of aircraft. However, an electric airplane and an eVTOL have notable differences that impact their motor designs.
An electric airplane swaps the current gasoline engine propellor system for an electric motor propellor system. They typically have one or two propellers, but may have up to four. Their electric motor gives them quiet operation and high efficiency during the high-torque, high-power takeoff and landing operations.
eVTOL aircraft use electric power to takeoff, hover, and land vertically. They come in various shapes and forms, with many having the appearance of a hybrid airplane or helicopter with wings and multiple propellers. It is common for eVTOLs to have 6, 8, or 12 propellers, but many other variations are under exploration. Depending on the eVTOL design, some of the propellers are positioned vertically, others horizontally, and in some cases, they can tilt.
Across the world, aircraft companies are developing and prototyping various eVTOL models. Yet, it is unlikely that the average person has seen one or will for some time — the first expected certified flight should launch in 2025.
Electric Aircraft Motor Features
Any electric motor, whether used for an aircraft or vehicle, uses two main components to create motion: a stator and a rotor. The stator is the stationary part of a motor that converts electricity into magnetic force. The magnetic force interacts with the rotor, the rotating part of the motor, which causes it to move. Electric motors drive the propellers on eVTOLs and electric airplanes to create the lift and thrust necessary to fly. Naturally, these motors need to be powerful but light in weight.
Carpenter Electrification makes Hiperco®, a high cobalt alloy used in stators and rotors. This alloy is an ideal fit to strike the necessary balance between power and weight for electric motors. With Hiperco® alloys, you can expect 30% higher power density and an increase in motor efficiency by up to 3%. This means an identically sized motor can have 25% higher torque as compared to other alloys, or the same torque and power output can be achieved with a 30% reduced footprint. Additionally, our industry-leading soft-magnetic materials offer:
- Improved transient response
- Cooler running temps for lower thermal stress
- Direct drive reliability
- Downsized battery pack for less weight
- Longer range and endurance
That same electric motor can be configured to generate electricity from motion. These generators are often used in hybrid and electric aircraft to create electricity to power flight instruments, control systems, HVAC, and other onboard systems that require electricity.
Electric Aircraft Motor Benefits
The movement toward electric motors is increasingly popular due to the many benefits of using these kinds of motors. For example, electric aircraft are much quieter than jet and combustion engine-based aircraft because the motor is quieter. Distribution propulsion in an eVTOL uses several small electric motors to drive propellers to create lift and thrust while being quester than one single, large, combustion motor and propeller system. Thanks to the advancements in battery technology and the size, power, and efficiency of electric motors, distributed propulsion is now a viable option when it once wasn’t.
Other essential benefits of using electric aircraft motors include the following:
- Electric aircraft — airplanes or eVTOL — do not emit greenhouse gases. Air travel today is currently estimated to account for 2.5% of total greenhouse gas emissions in a year. Greenhouse gases have been conclusively linked to climate change, making electric aircraft better for the environment.
- eVTOL manufacturers anticipate their aircraft will be safer than conventional aircraft, like helicopters. An eVTOL uses multiple propellers versus a single propeller. These propellers are also designed to shift power to the remaining propellers if one of the motors fails.
- Electric motors have fewer parts than gas turbine engines and combustion engines, promising lower maintenance costs. Electric motors in other designs, such as vehicles, have a well-established reliability record.
Working with Carpenter Electrification, you can also rest easy knowing our solutions, such as our alloys, stators, and rotors, are stress-tested in the real world.
The Future of Electric Planes and Aircrafts
The future of electric aircraft will come in stages. With the industry’s current and foreseeable technology, electric aircraft will be best suited for shorter trips. Regional air mobility (RAM) and urban air mobility (UAM) are terms associated with these shorter trips.
RAM refers to point-to-point flights or a city-to-city destination ranging from 100 to 300 miles. Today, these commercial services are offered with small, gas-powered, propeller airplanes. Mountainous locations like Alaska or island chains make use of small airplanes frequently. In fact, it is a common sight to see a sea plane at an Alaskan port. Electric aircraft could reduce fuel costs and the emissions from these frequent flights perfectly — and airline operators know it. Several are planning to begin commercial electric aircraft flights for four to 20 passengers within the next five to 10 years.
At 75 miles or less, UAM travel is even shorter and typically confined within a city or other smaller area of land. UAM industry experts often refer to these planes as air taxis. They carry four to six passengers and generally are used for quickly transporting travelers from a large airport to their ultimate destination — for example, a shuttle from IAH in Houston to the outlying Energy corridor. Large airlines like United, American Airlines, and Delta have invested in eVTOL start-ups to capitalize on situations like this.
UAM can also option a faster, more environmentally friendly travel option within large cities. Sprawling metropolitan areas, like Paris or Los Angeles, are infamous for traffic problems. Networks of take-off and landing ports are envisioned in these cities to provide quicker, more convenient alternatives for transit in the form of UAM. eVTOL could also replace conventional helicopters for urban travel within cities. As the port infrastructure and aircraft fleets grow, this mode of flying should become even more popular.
The final frontier for electric aircraft will be mid-range and long-range flights; however, significant technological advances are needed to become commercially viable. Because ultimately, the success of aerospace electrification depends on high motor and generator power density. Our high-induction soft magnetic alloys and stacks can help achieve the goal of fully electrified flight.
We can help address your motor design needs for current and future electric airplanes and eVTOLs. Learn more about electric aircrafts in our video here.