Advanced Air Mobility: Electric Propulsion Puzzle
Advanced Air Mobility (AAM) spans a localized aviation ecosystem running on electric aircraft that would serve intra-city and inter-city cargo, passenger, recreational, and private operations. At the heart of these operations is electric propulsion technology with its meticulous design promising a balanced weight-to-power, reliability, and efficiency ratio.
However, the facets of this equation are still a little out of balance owing to various factors that currently challenge the successful integration of electric propulsion in eVTOLs. These factors range from thermal stability to weight management, design optimization, and energy density limitations.
The imperative to address these complications looms larger as the eVTOL commercialization timeline comes closer. For now, the EIS (Entry-In-Service) timeline is being considered 2025 – 2030 and it is estimated that around 15 eVTOL companies will get their certification for commencing commercial operations within this duration. Therefore, most manufacturers are focusing on improving their battery chemistries, designs, and overall VTOL configurations to get over these impediments.
Innovations Addressing Major Challenges With Advanced Air Mobility Propulsion Technology
Energy Density
Several innovative approaches are underway to address the energy density requirement for eVTOL operations. The most peculiar ones include advanced battery chemistries, better charging mechanisms, cooling technologies, and collaborative research efforts. In terms of battery chemistry advancement, solid-state, hybrid, and sodium-ion batteries are being looked into by several key industry players like Toyota, QuantumScape, Silo, etc. Similarly, key institutes like Oak Ridge National Laboratory are investigating battery materials in the context of eVTOLs.
Power Electronics Reliability
The risk of software failures and electronic malfunctions runs high in eVTOLs warranting the need for rigorous testing protocols and fault-tolerant systems. This is leading to further studies and early research on the application of redundant power systems and AI-driven predictive diagnostics that proactively intercepts chances of component failure or instability to avoid malfunctioning at the eleventh hour. All industry majors including Volocopter, Lilium, Beta, and Pipistrel are trying to address this challenge and have developed some interesting design approaches in this context. For example, Lilium has incorporated a modular power system in its eVTOL design while Beta Technologies’ energy management systems are using AI to keep a check on battery performance in real-time.
Safety Standards and Regulatory Compliance
Globally, the regulatory frameworks are under development and it is anticipated that developed nations will bring forth a complicated certification system to ensure a fault-proof system for approval. Also, once operations commence integration of eVTOLs in air traffic systems will be a key challenge, especially with respect to semi and fully autonomous aircraft.
Authorities worldwide are trying to resolve this conundrum through private-public initiatives and partnerships. For instance, Joby Aviation collaborated with Nomura Real Estate and ANA Holdings to develop eVTOL infrastructure in Japan. The former also entered into a collaborative effort with NASA to assess eVTOLs integration with air traffic systems. The simulations for the same were completed in 2024. It also secured exclusive rights in Dubai to operate air taxis in February 2024.
Final Word
The propulsion challenges in eVTOLs have slowed down the pace of AAM development to some extent, but the ongoing research efforts and innovations will resolve most of these within the next 3-4 years. As the urban air mobility market gains momentum, further innovations are expected down the road that will ease the weight, range, and safety aspects of eVTOLs propulsion.
