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Advanced air mobility (AAM) is a broad concept enabling consumers access to on-demand air mobility, cargo and package delivery, healthcare applications, and emergency services through an integrated and connected multimodal transportation network. However, a number of challenges could impact AAM’s growth potential, such as autonomous flight, the availability of take-off and landing infrastructure (i.e., vertiports), integration into airspace and other modes of transportation, and competition with shared automated vehicles. This article discusses the results of a demand analysis examining the market potential of two potential AAM passenger markets—airport shuttles and air taxis. The airport shuttle market envisions AAM passenger service to, from, or between airports along fixed routes. The air taxi market envisions a more mature and scaled service that provides on-demand point-to-point passenger services throughout urban areas. Using a multi-method approach consisting of AAM travel demand modeling, Monte Carlo simulations, and constraint analysis, this study estimates that the air taxi and airport shuttle markets could capture a 0.5% mode share. The analysis concludes that AAM could replace non-discretionary trips greater than 45 min; however, demand for discretionary trips would be limited by consumer willingness to pay. This study concludes that AAM passenger services could have a daily demand of 82,000 passengers served by approximately 4000 four- to five-seat aircraft in the U.S., under the most conservative scenario, representing an annual market valuation of 2.5 billion USD.

Accurate weather forecasts of precipitation events hinge on both a complete understanding and an accurate representation of rain formation processes. A major uncertainty in precipitation development is how the large drops necessary to initiate coalescence growth are created in a realistic time. One explanation for accelerated coalescence growth onset in real clouds is the presence of giant aerosol, having large sizes that permit earlier onset of coalescence growth and thus precipitation formation. Numerical modeling studies have shown these giant aerosol can be important in continental clouds, but past studies have disagreed about their importance in maritime clouds. The present study examines the role of giant aerosol in marine trade wind cumuli with a new analysis method using a new extensive dataset collected during the Rain in Cumulus over the Ocean (RICO) field campaign. Giant aerosol particles are quantified from clear-air aircraft data, and the precipitation development in the clouds is tracked with dual-polarization radar data. These data are used and compared with the results from an adiabatic parcel model run for typical environmental conditions and aerosol concentrations on each day of interest. Despite all clouds being pristine and maritime, this study reveals a varying role of giant aerosol on precipitation formation, governed by the observed CCN and resulting drop concentrations in the clouds. The giant aerosol appear to be important for precipitation development on days with high CCN concentrations where droplet growth is slower and relatively unimportant on days with low CCN concentrations where coalescence is able to initiate effectively in the absence of giant aerosol. The overall development of precipitation is found to be strongly influenced, however, by environmental factors limiting cloud development on many of the days. Differences in the observed radar echo evolution and the modeled precipitation development also suggest that the clouds may \"linger\" at low radar reflectivities for an extended period of time before the onset of higher reflectivities associated with precipitation.

Advanced air mobility (AAM) is a broad concept enabling consumers access to on-demand air mobility, cargo and package delivery, healthcare applications, and emergency services through an integrated and connected multimodal transportation network. However, a number of challenges could impact AAM’s growth potential, such as autonomous flight, the availability of take-off and landing infrastructure (i.e., vertiports), integration into airspace and other modes of transportation, and competition with shared automated vehicles. This article discusses the results of a demand analysis examining the market potential of two potential AAM passenger markets—airport shuttles and air taxis. The airport shuttle market envisions AAM passenger service to, from, or between airports along fixed routes. The air taxi market envisions a more mature and scaled service that provides on-demand point-to-point passenger services throughout urban areas. Using a multi-method approach comprised of AAM travel demand modeling, Monte Carlo simulations, and constraint analysis, this study estimates that the air taxi and airport shuttle markets could capture a 0.5% mode share. The analysis concludes that AAM could replace non-discretionary trips greater than 45 min; however, demand for discretionary trips would be limited by consumer willingness to pay. This study concludes that AAM passenger services could have a daily demand of 82,000 passengers served by approximately 4000 four- to five-seat aircraft in the U.S., under the most conservative scenario, representing an annual market valuation of 2.5 billion USD.