# Advanced Air Mobility: Opportunities and Challenges Deploying eVTOLs for Air Ambulance Service
## 2 Literature Review  
Around the world, communities are experimenting with the use of advanced air mobility to serve a variety of medical response and pandemic use cases such as social distancing reminders, essential equipment and medical supply delivery, and virus detection [6; 7; 8; 9]. Airspace Systems, a California AAM startup, has developed software that can help public agencies use drones to monitor social distancing and face mask compliance [10]. Similarly, in Elizabeth, New Jersey, the police department has used drones equipped with an automated message to remind the public to social distance during the pandemic [11]. In the U.S., the United Parcel Service (UPS) and CVS Pharmacy began using Matternet M2 drones to deliver prescription medications to a retirement community in Florida during a COVID-19 stay-at-home order in May 2020 [12]. In remote areas, advanced air mobility has the potential to reduce the time to access medical supplies and testing from hours using surface transportation to 15 min by drone in some cases [13]. In parts of Africa, the use of drones is becoming a growing part of rural healthcare delivery. In Rwanda, Zipline has used fixed-wing drones to airdrop medical supplies and ferry tests from numerous hospitals across the region [14]. In response to the global pandemic, the company began transporting COVID-19 test samples from remote parts of Ghana that do not have testing facilities to laboratories in more populated regions of the country [15]. The service has also expanded access to medical care for patients who are unable to travel due to COVID-19 restrictions. For example, drones are being used to deliver cancer drugs to patients in remote villages who are unable to travel to oncology centers during the pandemic [16]. These case studies represent a handful of emerging examples of how advanced air mobility has the potential to expand access to healthcare [17; 18]. In spite of the large number of potential aeromedical use cases, air ambulances only serve a small percentage of critical medical transports [5]. Historically, the high cost of air ambulance service limits the use of air transportation to patients in remote areas or the most critical medical situations where minimizing transport time to a hospital is critical to saving a patient's life [19]. Although existing studies on the use of electric aircraft and other emerging aviation technologies for aeromedical use are limited, an emerging body of research suggests that emergency medical AAM services may confront a number of technical and business model challenges. Yet, these same aeromedical use cases may be important to building public acceptance of novel aircraft designs and technologies [20]. A study by [PERSON] et al. [21] found that near-term electric aircraft are not expected to meet the technical requirements of air ambulance service, nor will they likely provide cost savings over existing services using helicopters. Internationally, [PERSON] et al. [22] conducted a cost analysis of electric vertical take-off and land (eVTOL) aircraft for an air ambulance system in Japan. The study's scenario analysis concludes that differences in battery capacity can have notable differences in future cost models due to the relatively high cost of battery replacements. [PERSON] et al. [22] also compare the potential viability of eVTOLs to existing helicopters using a standardized operational concept for air ambulance service. This study builds upon prior literature by studying the feasibility of eVTOLs for aeromedical use in the United States. According to the National Emergency Medical Services Information System (NEMSIS) and the National Association of State Emergency Medical Service Officials (NASEMSO), there are an estimated 36 million medical transport trips served by ambulances annually. However, only approximately 1.5% of these trips (roughly 550,000) are served by air ambulances every year [23; 24].