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Crash Manouevring

It is the application of brake air , while  engine is still running (turning ) in opposite direction

In B&W

  • Acknowledge the bridge request for reversal of direction
  • Start air cam gets reversed due to telegraph acknowledgement.
  • Fuel is cut off by running direction interlock.
  • Put the fuel lever to " 0 " setting.
  • When rpm reduces to 20 % to 40% MCR rpm , put the fuel lever to min: start setting.
  • Astern rpm is much less than ahead rpm as engine is tremendously overloaded due to increased propeller slip.
  • Start air becomes braking air because start air cam reversal allows air supply in for astern timings , when the engine is still moving with ahead timings
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