CS 25.1337 Powerplant instruments

• ED Decision 2003/2/RM found in: CS-25 Amdt 27 - Large Aeroplanes (Jan 2023)

CS 25.1337 Powerplant instruments ED Decision 2003/2/RM (a) Instruments and instrument lines (1) Each powerplant instrument line must meet the requirements of [CS 25.993](#_DxCrossRefBm1709821479) and [CS 25.1183](#_DxCrossRefBm1709821170). (2) Each line carrying flammable fluids under pressure must – (i) Have restricting orifices or other safety devices at the source of pressure to prevent the escape of excessive fluid if the line fails; and (ii) Be installed and located so that the escape of fluids would not create a hazard. (3) Each powerplant instrument that utilises flammable fluids must be installed and located so that the escape of fluid would not create a hazard. (b) *Fuel quantity indicator*. There must be means to indicate to the flight-crew members, the quantity, in litres, (gallons), or equivalent units, of usable fuel in each tank during flight. In addition – (1) Each fuel quantity indicator must be calibrated to read ‘zero’ during level flight when the quantity of fuel remaining in the tank is equal to the unusable fuel supply determined under [CS 25.959](#_DxCrossRefBm1709820721); (2) Tanks with interconnected outlets and airspaces may be treated as one tank and need not have separate indicators; and (3) Each exposed sight gauge, used as a fuel quantity indicator, must be protected against damage. (c) *Fuel flow meter system*. If a fuel flow meter system is installed, each metering component must have a means for bypassing the fuel supply if malfunction of that component severely restricts fuel flow. (d) *Oil quantity indicator*. There must be a stick gauge or equivalent means to indicate the quantity of oil in each tank. If an oil transfer or reserve oil supply system is installed, there must be a means to indicate to the flight crew, in flight, the quantity of oil in each tank. (e) *Turbo-propeller blade position indicator.* Required turbo-propeller blade position indicators must begin indicating before the blade moves more than 8° below the flight low pitch stop. The source of indication must directly sense the blade position.