🔍 Key Concepts

• Review how a Synchro-Self-Shifting (SSS) clutch engages – is it hydraulically/air operated or purely mechanical and speed‑sensing? • Think about which shaft in a gas‑turbine reduction gear train must be slightly faster for the clutch teeth to line up and self‑engage. • Use the illustration labels (Input Assembly, Output Assembly, Main Sliding Assembly) to visualize which side is driving (turbine) and which side is driven (gear train).

💭 Think About

• Ask yourself: does an SSS clutch need any external fluid (oil, LP air, HP air) to push it into engagement, or does it automatically engage when the correct speed relationship exists? • Between the turbine input shaft and the reduction gear shafts, which one has to be leading in speed so the clutch can smoothly pick up the load without shock? • Look at the gear train: if one shaft is ahead in rpm and the other is lagging, which combination would avoid back‑driving the turbine when disengaged?

✅ Before You Answer

• Eliminate choices that require external air supply if you know an SSS clutch is a mechanical, speed‑sensing device. • Identify which answer states a condition where the driving shaft speed is greater than the driven shaft speed, which is necessary for self‑synchronizing engagement. • Confirm that the condition you pick would allow the clutch to engage automatically as speeds match, without manual or pneumatic actuation.