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Minimum control speeds (VMCs) are so-called V-speeds that are included in the limitations section of airplane flight manuals (AFM) of all multi-engine airplanes. In general, a minimum control speed is the calibrated airspeed below which directional or lateral control of an airplane (i.e. the desired heading or bank angle) on the ground (runway) or in the air can no longer be maintained by the pilot after failure of a wing-mounted engine, or while such an engine is inoperative, as long as the thrust of the opposite engine on the other wing is at the maximum (takeoff) setting. VMCs are also used by airplane design engineers for sizing the vertical tail or stabilizer and the aerodynamic flight control surfaces. Many manuals for pilots and reports by accident investigators present and use VMCs as they are defined in aviation regulations that are for design and certification of multi-engine airplanes, such as FAR 23 or FAR 25 or equivalent and not as they apply to the operational use of the airplanes by pilots. Therefore, this article intends to bridge the knowledge gap between design engineers, flight-test crews, multi-engine rated (airline) pilots, and airplane accident investigators, by explaining the minimum control speeds VMC as taught by aeronautical universities and used in airplane design and by (experimental) test pilot schools, such as the USAF Test Pilot School, the Empire Test Pilot's School and the US Naval Test Pilot School. == Regulatory minimum control speeds VMC == Aviation regulations (such as FAR and EASA CS parts 23 and 25 and equivalent)〔〔 define several different VMC’s and require design engineers to size the vertical tail and the aerodynamic flight controls of the airplane to comply with these regulations. The minimum control speed airborne (or in the air - VMCA) is the most important minimum control speed of a multi-engine airplane. In many aviation regulations and AFMs, VMCA is listed as VMC though,〔〔 with the addition that VMC is the minimum control speed for the takeoff configuration. However, during other flight phases, such as continued takeoff after flap retraction, cruise flight and approach for landing when the flaps are still up, a VMCA applies as well. Therefore most test pilot schools teach to use VMCA, rather than VMC, and include the airplane configuration or flight phase with it. Other defined VMCs are minimum control speed on the ground (VMCG) and minimum control speed during approach and landing (VMCL). In addition, on four or more engine airplanes, VMCs exist for cases with either one or two engines inoperative (on the same wing). Figure 1 illustrates the VMCs that are defined in the applicable civil aviation regulations〔〔 and in military specifications. The following table lists all VMCs. To avoid misunderstanding, this article uses VMC(A) when either VMCA or VMC for a flight phase is meant. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Minimum control speeds」の詳細全文を読む スポンサード リンク
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