TM 55-1560-307-13&P WARNING     ELECTRICAL GROUNDING OF THE HELICOPTER.   Army regulations require the grounding of the helicopter when parked and during all fueling and defueling  operations.    No  electrical  switches  shall  be operated  except  those  necessary  for  servicing  during fueling and defueling.     Fueler must exercise caution during fueling.  If fuel is   spilled   inside   the   aircraft,   removal   of   cabin   floor panels   may   be   required,   aircraft   purged   with   clean water,  and  allowed  to  air  dry.    All  spilled  fuel  must  be removed   prior   to   continuing   operation.      See   TM   55- 1520-240-23 for additional instructions, para 2-204. 3-13. PRESSURE REFUELING. This task covers: a.     Grounding procedures. b.     Refueling ERFS tanks. INITIAL SETUP Tools:  Flashlight (explosion proof). Materials/Parts: JP-4,-5,-8 (items 7, 8, 9, Appx D) Refueling Truck Refueling Adapter Nozzle, P/N AE82605R Equipment Conditions: Same as gravity refueling. Refer to Figure 3-2. 1. Ground the helicopter as required. CAUTION No  aircraft  electrical  power  or  auxiliary power   unit   is   required   when   pressure fueling or defueling. 2. Connect fuel hose ground wire (1) to tank receptacle (2). 3. Remove  dust  cap  from  coupling  assembly  on  hose (3). WARNING The  ERFS  vents  must  be  open  during refueling and defueling operations.  The ERFS    tanks    cannot    be    exposed    to internal pressure of over 5 psi, or failure will occur. 4. Remove fuel filler port (4) cap. 5. Install   pressure   refueling   adapter   (5)   to   manifold hose (3), and install fuel truck D-1 pressure hose (6) to adapter. 6. Refueling sequence.  Tank 4, 3, 2, 1 rear to forward due to a 2 degree nose up attitude of the aircraft. NOTE After all tanks are filled, do not open all 4 tank  cam  levers  at  the  same  time.    Fuel will  seek  its  own  level  and  could  cause tanks   3   and   4   to   overfill.      This   could cause a fuel spill. 7. Ensure tank cam lever on tank to be filled is opened and   closed   on   other   tanks.      Isolate   other   tanks   by closing the quick disconnect coupling on hose connected from cam lever to manifold TEE. 8. Start  pressure  refueling  at  no  greater  than  35  psi truck   delivery   pressure   and   150   gallons   per   minute maximum. 9. With  an  explosion  proof  flashlight,  carefully  watch fuel  level  and  stop  refueling  when  level  is  up  to  top  of fuel filler port. 10.  Close tank cam lever and proceed to the next tank to be filled. 11.  Close  either  side  of  hose  coupling  to  isolate  filled tank before filling next tank. 3-14