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underspeed condition
Definição1
A propeller governor is in its underspeed condition when the engine is operating at a speed lower than the governor calls for. The speeder spring holds the pilot valve down and the flyweights in. With the pilot valve down, the governor directs oil in the proper direction to decrease the pitch of the propeller blades. When the blade pitch decreases, the RPM increases, the governor flyweights spin out to an on-speed condition, and oil is trapped in the propeller to hold the pitch.
Fonte1
CRANE, Dale (ed.). Dictionary of aeronautical terms. 2nd ed. Renton: ASA, 1991.
Fonte2
INTERNATIONAL CIVIL AVIATION ORGANIATION. Annex 8 to the Convention on International Civil Aviation. Airworthiness of aircraft. 11th ed. Montreal, 2010.
Nota adicional1
Information regarding this term is a result of researches developed by DECEA in cooperation with ANAC.
Contexto
b) Rotor underspeed warnings for single engine helicopters, and for multi-engine helicopters not having an approved device for automatically increasing power when an engine fails. When the helicopter approaches a rotor rotational speed limit, with or without engines inoperative, clear and distinctive warnings shall be apparent to the pilot. The warnings or initial characteristics of the condition shall be such as to enable the pilot to arrest the development of the condition after the warning begins and to recover the rotor rotational speed to within prescribed normal limits and to maintain full control of the helicopter.
Subárea1
Rotorcraft
Related Term
overspeed condition
Português
condição de baixa velocidade