SPIRAL UP

CLOSE THE GAP

Systems Trivia: H60T Transmission

by · Published · Updated

  1. Q: Function of the input modules? 
    A: Allow the engine to drive the transmission and allows the transmission to spin freely when drive from the the engines is absent (free wheeling unit). 
     
  1. Q: Function of the accessory modules? 
    A: Drive an AC generator and a hydraulic pump (not contingent on the engine – transmission drives these even in an autorotation). 
     
  1. Q: Function of the main module? 
    A: Transfers individual or combined engine output to the main and tail rotors. Also, houses the internal lubrication system that lubricates all five MGB modules. 
     
  1. Q: Basics of the transmission lubrication system? 
    A: Wet sump, all internal system. Only external lines are to the oil cooler.  
     
  1. Q: Basics of transmission oil supply? 
    A: Two pumps are driven by transmission gears. The pumps provide oil through a filter then an oil cooler. The pressure sensor and temp switch are located after the cooler. The pressure switch is on the no. 1 accessory module (farthest from the pumps) and the temperature sensor is in the main module sump. 
     
  1. Q: Basics of transmission oil scavenge? 
    A: The same two pumps recycle the oil back to the main module sump. 
     
  1. Q: Components of the transmission lubrication system monitoring? 
    A: A  temp and pressure sensor and a temp and pressure switch are in the supply and chip lights for each module are in the scavenge. The sensors and switches are independent and are at different locations in the supply.
     
  1. Q: Oil filter bypass? 
    A: Bypass is indicated by a red button. Viewed through a sight glass. If the button is popped, it can’t be reset without removing the filter. In flight, if a bypass is indicated you can continue. If the bypass indication is discovered on preflight, maintenance action is required.  
     
  1. Q: Tail rotor drive shaft sections? 
    A: Five drive shaft sections connected by viscous (oil filled) bearings and flex (thomas) couplings. 
     
  1. Q: Tail modules? 
    A: Intermediate gearbox, trail rotor gear box. 
     
  1. Q: Intermediate gearbox rpm? 
    A: 4000 decreased to 3000. 
     
  1. Q: Tail gearbox rpm? 
    A: 3000 decreased to 1000. 
     
  1. Q: Tail gearbox lubrication? 
    A: Each gearbox uses a wet sump “splash” system. 
     
  1. Q: Tail gearbox monitoring? 
    A: Each gearbox has a temp./chip switch. 
     
  1. Q: Temp. switch and “fuzz” burn activation and deactivation? 
    A: Temp. switch is activated at 140 °C and “fuzz” burn is deactivated at the same temp. 
     
  1. Q: Sight gauge? 
    A: Each gearbox has a sight gauge. At a minimum, the oil level needs to be at the bottom of the circle on the glass.  
     
  1. Q: Transmission lubrication system sequence? 
    A: Wet sump, pumps, filter, cooler pressure and temp sensor, manifold, modules/generators (pressure switch on lt accessory module), input/accessory chip detectors on scavenge, main module chip detector in wet sump. 

Leave a Reply

Your email address will not be published. Required fields are marked *