Joby Aviation’s vision for aerial ride-sharing could make your commute five times faster – as well as cleaner, safer, and better for your city. Read on to learn more about the Joby S4.
Aerial Ride-Sharing – The Joby Perspective on UAM
By: Dawn M.K. Zoldi, Guest Contributor
This week at the Electric & Hybrid Aerospace Technology Virtual ‘Live,’ Gregor Veble Mikić, Flight Physics Lead for Joby Aviation, discussed their eVTOL S4 aircraft and business model, worth noting as they are valued at more than $6BUSD and climbing.
Mikić described the S4 as a “distillation of many efforts in development for 10 years.” It features a range of over 240km at a speed of over 340km/hour; seats for 5 people (1 pilot + 4 passengers), low acoustic signature (65dBA at 100m hover), and contains “airline-level triple redundancy in safety.”
The company’s vision is to launch a global-scale vertical integrated ground-based taxi service like Uber for cars but “aerial ride-sharing to unleash the 3rd dimension of transportation.” Mikić says in major metropolitan areas, their ride will be five times faster than driving. Even better, the infrastructure will be a fraction of the cost of rail or highway development.
To make this vision a reality, key objectives for the vehicle’s design included: safety, noise, payload, range and speed. According to Mikić, “Safety is a hard constraint and all the others are relevant to economic viability.” Noise, he explained, was crucial because they want to bring this aircraft close to people. Range determines the size of the potential market. Speed increases passenger benefits and utilization of the vehicle.
The vehicle is complex because it has to provide thrust both when hovering and in a forward direction in other aspects of flight. They decided to use the same propulsion systems for both, resulting in a clean airframe with superior performance in range and speed, keeping safety first in mind. With regard to safety, they designed the vehicle for redundancy. The fact that power units must be used for both lift and control created unique challenges for redundancy, in the event of a loss of flight. To overcome this, they utilized six rotors to ensure minimum redistribution of power under failure. They also incorporated multiple battery packs, attached to multiple rotors to optimize resiliency.
Propellers were also key, as they drive both performance and acoustics. In hover, the vehicle has to provide efficient thrust while having a low acoustic signature. This is affected by the tip speed of the propeller. However, lowering tip speed often compromises forward flight efficiency. Joby primarily focused on acoustics, but according to Mikić were still able to still incorporate efficiency for forward flight through their unique tilt-prop shape design and blade placement.
Finally, Joby enhances safety through the use of automation in the majority of its systems. They designed the aircraft for automatic reconfiguration under loss of function of any component. Automation also reduces pilot workload so they can focus on flight instead of system management, which also increases safety of flight. Simplified vehicle operations including attitude control or station-keeping in hover were core design principles for command of the vehicle to enable the pilot to focus on navigating and higher level aviation tasks. “Increasing automation puts us on the path to complete autonomy,” according to Mikić.
Will Joby aerial ride-sharing be coming soon to a city near you? Hard to say, but clearly, Joby has the vision, the capital and the aircraft to make it so.
