This article presents an analytical framework for investigating the cruise performance of conventional helicopter configurations. Starting from the analysis of power required in straight-and-level flight, endurance and range performance of turbine- and battery-powered rotorcraft are considered, for which it is assumed that fuel consumption and constant-power battery discharge models are, respectively, made available. The original contributions of the article are represented by (a) a closed-form formulation for expected endurance and range for both classes of vehicles, where electrical helicopters have not been dealt with in previous studies and (b) the analytical derivation of an accurate estimate for best endurance and best range airspeeds as a function of relevant system parameters. The approach is validated by analyzing two reference helicopters, showing good physical insight and better accuracy with respect to other techniques available in the literature, for the identification of an energy-efficient cruise flight strategy.

本文提出了一个分析框架，用于研究常规直升机配置的巡航性能。从直线平飞所需功率分析出发，考虑涡轮动力和电池动力旋翼机的续航和航程性能，假设分别建立燃料消耗模型和电池恒功率放电模型可用的。文章的原始贡献由 (a) 两类车辆的预期续航时间和航程的封闭式公式表示，其中电动直升机在以前的研究中没有处理，以及 (b) 准确估计的分析推导作为相关系统参数的函数，以获得最佳耐力和最佳航程空速。