Maritime Knowledge Base
Browse questions and answers across marine machinery, merchant navy careers, shipboard operations and maritime glossary terms.
Browse by Category
Marine Machinery
Troubleshooting guides for pumps, boilers, purifiers, compressors and auxiliary systems.
Merchant Navy Careers
Questions about joining the merchant navy, exams, cadetships, ranks and sea-time.
Maritime Glossary
Plain-English definitions of shipping, engine-room, navigation and regulatory terms.
Shipboard Operations
Practical Q&A for watchkeeping, safety, maintenance routines and onboard documentation.
Results for "Turning gear"
Why won't the main engine start on air?
A main engine that turns on air but will not fire, or will not turn at all, points to a short list of common causes across the starting-air, fuel and control systems.
Marine MachineryWhat is a reduction gearbox on a ship and why is it used?
A reduction gearbox lowers the high rotational speed of a medium- or high-speed engine to the slower speed that turns an efficient propeller, and can combine several engines onto one shaft.
Marine MachineryWhat is the difference between a controllable-pitch and a fixed-pitch propeller?
A fixed-pitch propeller has blades set at one permanent angle, while a controllable-pitch propeller can rotate its blades to vary thrust and go astern without reversing the engine.
