The Gas Turbine Engine (GTE) is directly coupled to which component?

The Gas Turbine Engine (GTE) is directly coupled to which component?

• A. Main crankshaft
• B. High Speed (HS) pinion shaft
• C. Turbine rotor shaft
• D. Low Speed (LS) pinion shaft

Answer: (B)

Power from a gas turbine is carried by the engine’s high-speed drive shaft into a reduction gearbox. The input gear of that gearbox is a pinion mounted on the high-speed shaft, so the engine is directly coupled to the high-speed pinion shaft. This arrangement lets the turbine’s very high rpm be stepped down to a usable speed for generators, pumps, and other accessories. The other options don’t fit because a gas turbine doesn’t use a crankshaft like a piston engine, and while the turbine rotor shaft is the power source, the direct coupling to the gearbox input is specifically the high-speed pinion shaft, with the low-speed pinion shaft handling other, lower-speed accessory drives.

Power from a gas turbine is carried by the engine’s high-speed drive shaft into a reduction gearbox. The input gear of that gearbox is a pinion mounted on the high-speed shaft, so the engine is directly coupled to the high-speed pinion shaft. This arrangement lets the turbine’s very high rpm be stepped down to a usable speed for generators, pumps, and other accessories. The other options don’t fit because a gas turbine doesn’t use a crankshaft like a piston engine, and while the turbine rotor shaft is the power source, the direct coupling to the gearbox input is specifically the high-speed pinion shaft, with the low-speed pinion shaft handling other, lower-speed accessory drives.