Abstract: A VTOL aircraft includes a lift propeller configured to provide lift during takeoff, landing and hover operations. The lift propeller is configured to be stowed close to a boom surface when not in use during, e.g., cruise flight, to minimize drag around propeller surfaces. The lift propeller may be displaced vertically with respect to the boom when switching to a lift configuration to provide greater separation from the boom to improve lift efficiency and reduce unwanted vibrations. The lift propeller may have a fail-safe configuration that allows the propeller to move passively between lift and stowed configurations, and to fully rotate even when fully retracted.

Abstract: In large distributed computing environments, application execution may be distributed between a plurality of groups, the plurality of groups containing a set of host computer systems responsible for the execution of one or more operations of the application. Group membership may be determined by generating configuration information based at least in part on the plurality of groups. The configuration information may be provided to a plurality of host computer systems and each host computer system of the plurality of host computer systems may determine membership to a particular group of the plurality of groups based at least in part on the configuration information.

Abstract: A method, system and program product includes capturing at least a location of a user and communicating with a server system. The server system is operable for extracting crime incident data sets from data sources, processing the collected data, and generating forecasted incident risks for a plurality of geographical locations. A forecasted incident risk for the location is received. A notification for the user is generated. The notification at least includes a change in the forecasted incident risk for the location. A representation of the forecasted incident risk and the change in the forecasted incident risk is displayed.