🔍 Key Concepts

• Count how many distinct gear "stages" the power passes through from input shaft to output shaft to decide between single vs double reduction. • Look for any clutch packs, cone clutches, or sliding gears that would allow the output shaft to be driven in ahead and astern without changing engine rotation – that’s what makes a gear reversing. • Identify whether there is one engine driving the gear (single input) or some arrangement for multiple engines/inputs.

💭 Think About

• Trace the power flow: starting at the engine input shaft, how many separate meshes between small and large gears does the torque go through before reaching the output shaft? • Examine the output side: do you see any mechanism that could disengage and re‑engage different gears to reverse the propeller, or is it just a fixed train of gears? • From the housing and flange arrangement, does the drawing suggest more than one input shaft, or a single main input from one engine only?

✅ Before You Answer

• Be sure you can clearly see two different size gear meshes in series if you decide it is double reduction. • Confirm whether there is an obvious reversing clutch or sliding gear on the output shaft before choosing a reversing option. • Verify you see only one main input shaft from the engine before committing to any answer.