As more eVTOL and hybrid aircraft developers enter the urban air mobility (UAM) space, more deals are being made to build and establish infrastructure for these aircraft. Protecting these facilities and the people involved will be critical.
In this industry, there are many facets and functions to consider. Fire protection can be easily pushed to the background, marked as non-essential or forgotten altogether. Luckily, there are a few individuals who make fire protection their primary focus. While eVTOL aircraft and infrastructure continue to be developed, fire protection professionals are monitoring the industry, understanding the unique fire problems, and working toward solutions in the best interest for all.
Current model codes, standards, and regulations do not cover the eVTOL industry. The majority of aviation-based codes and standards support fire protection for traditional liquid carbon-based fuels, and lack protection guidance specifically for UAM technologies. However, two organizations are working toward a solution: the National Fire Protection Association (NFPA) and the Vertical Flight Society (VFS). NFPA publishes more than 300 fire protection codes and has established a Vertiports Task Group for NFPA 418, Standard for Heliports.
Through the eVTOL Provisional Technical Committee, the H2 Hydrogen Council, and a series of hosted workshops, VFS is bringing together industry stakeholders to explore UAM and eVTOL infrastructure concerns. Until fire prevention guidance is officially developed, published, and adopted for UAM, the sector can refer to a number of existing codes to guide fire protection planning for these facilities and operations.
Typical models for UAM operations start and end with people moving through a terminal facility. The functions, operations, and fire protection requirements for these structures are outlined in NFPA 415, Standard on Airport Terminal Buildings, Fueling Ramp Drainage, and Loading Walkways. Passenger handling areas are also clearly addressed in this standard. Whether the structure is on an airport or located elsewhere, such as a standalone facility, rooftop, or parking garage, the guidance in this document is applicable and should be followed for fire protection.
The largest area of uncharted fire protection territory is associated with the eVTOL aircraft itself and its support infrastructure. It’s still unclear what hazards will be present, what the associated risks are, and how UAM will be protected. However, several documents already exist that provide steps in the right direction. For aircraft maintenance and hangaring, manufacturers can look to NFPA 409, Standard on Aircraft Hangars, and NFPA 410, Standard on Aircraft Maintenance. Current aircraft hangars are subject to the fire protection and construction requirements of NFPA 409. This document was previously based on protecting structures against liquid flowing fuel fires, which drove the requirements for foam and water-based fire protection systems. However, a major update to the document recognizes new technologies are being developed where a foam or water-based system may not be the best protection. The 2022 edition of NFPA 409 allows for a risk assessment and performance-based design approach, providing an option for protecting hangars that will house UAM and eVTOL aircraft assets.
NFPA 410, Standard on Aircraft Maintenance, provides clear guidance on the facility protection, operations, and safety of personnel who work on aircraft. This document outlines requirements that would equally apply to traditional aircraft, as well as aircraft powered by electricity, hydrogen, or other emerging propulsion technologies.
Guidance on the construction and protection of infrastructure can be based on the aircraft specific fuel systems. NFPA 855, Standard for the Installation of Stationary Energy Storage Systems, provides “the minimum requirements for mitigating the hazards associated with ESS [energy storage system].” For hydrogen-based aircraft and infrastructure, NFPA 2, Hydrogen Technologies Code, provides “fundamental safeguards for the generation, installation, storage, piping, use and handling of hydrogen in compressed gas form or cryogenic liquid forms.”
One of the biggest challenges with these emerging technologies may be to the local fire departments and first responders. How should they respond to emergencies related to these aircraft, whether in a facility, a crash situation, or an off-site emergency landing scenario? The above documents include emergency planning guidance. The emergency response principles for electric automobiles can be applied.
Proposals submitted to NFPA 440, Guide for Aircraft Rescue and Firefighting Operations and Airport/Community Emergency Planning, and to NFPA 418 include sections containing information for first responders on how to react to these emergencies. However, the best option is for aircraft manufacturers and infrastructure developers to communicate with jurisdictional fire departments, communicating early and often with first responders, and working together to develop emergency plans in the event of an emergency to the facility and its proposed operations. Providing training to become familiar with the aircraft, its energy system, and related support systems will enable fire departments to craft effective and safe response plans.
The codes and standards listed above can be used to help the sector prepare for future regulations in the UAM space, but a more thorough and direct approach is still necessary. The Vertiport Task Group for NFPA 418 is working to create fire protection standards, but it is difficult to do this without a full grasp on the range of systems currently in production.
To help the task force gather this information and set the direction of future fire protection requirements for eVTOL and emerging technologies in the UAM field, aircraft manufacturers can fill out the Aircraft Manufacturers Survey.
Taking part in this survey, knowing what codes and standards already exist, and creating, participating, and staying involved in committees and conversations with stakeholders will be the key to fire protection for UAM now and into the future.