FUEL SYSTEM The fuel system is comprised of three interconnected crash resistant fuel cells. Two forward fuel cells are located under the aft facing passenger seats. The aft fuel cell is located beneath and behind the aft passenger seat. Fuel from the two forward fuel cells is transferred to the aft fuel cell by means of a dual element ejector pump, located between the forward cells. All fuel cells are vented overboard by a common vent line.

L/FUEL PUMP R/FUEL PUMP FUEL LOW A dual element boost pump is located in the sump of the aft fuel cell. In the event of boost pump failure, flow switches activate the L/FUEL PUMP or R/FUEL PUMP caution light on the instrument panel. Fuel quantity probes are located in the left forward fuel cell and the aft fuel cell. A fuel quantity transmitter in the aft fuel cell is electrically connected to the fuel quantity probes and to the fuel quantity gage. A low fuel switch, located in the aft cell sump, is connected to the FUEL LOW caution light on the instrument panel. The caution light will illuminate when approximately 65 lb. (10 gal) of usable fuel remains in the aircraft. The fuel cell sump is also equipped with an electric solenoid drain valve, actuated by a button located on the lower right side of the aft fuselage

FUEL SYSTEM CAPACITY Total Capacity112.0 Gal. JP-4 (6.5 lb/gal)728.0 Lbs. JP-5 (6.8 lb/gal)761.6 Lbs. Usable Fuel110.7 Gal. JP-4 (6.5 lb/gal)719.6 Lbs. JP-5 (6.8 lb/gal)752.8 Lbs. Unusable Fuel1.3 Gal. JP-4 (6.5 lb/gal)8.5 Lbs. JP-5 (6.8 Ib/gal)8.8 Lbs.

FUEL SYSTEM 1 Helicopters not equipped with Fuel QTY switch 1 FUEL SYSTEM

RIGHT FWD CELL LEFT FWD CELL R/FUEL PUMP L/FUEL PUMP FLOW SWS CHECK VALVES INLINE FILTERS DUAL ELEMENT EJECTOR PUMP

DUAL ELEMENT ELECTRIC PUMPS FUEL PROBE FWD TANK FILLER PIPE EJECTOR PUMP RETURN LINE FUEL LOW SENSOR L R

FUEL SHUT-OFF VALVE FUEL PRESSURE TRANSDUCER

Pressure xmit Shut Off

2 SHORT PROBES (ONE FWD, ONE AFT) ONE LONG PROBE AFT

FULL Gal Lbs MOST FWD CG 70.0 Gal Lbs MOST AFT CG 46.9 Gal Lbs FUEL BURN vs CENTER OF GRAVITY A/C without Fuel Quantity Selector Switch installed

FUEL BURN vs CENTER OF GRAVITY A/C with Fuel Quantity Selector Switch installed FULL Gal Lbs 70.0 Gal Lbs MOST FWD CG 28.8 Gal Lbs MOST AFT CG 16.1 Gal Lbs

FUEL LOW EMPTY RED INDICATIONS FOR A/C WITHOUT FUEL QUANTITY SWITCH BLACK INDICATIONS FOR A/C WITH FUEL QUANTITY SWITCH All Weights are given for Jet-B Fuel

MOST AFT CG MOST FWD CG FULL

MAIN DRIVE SHAFT The main drive shaft consists of a flanged hollow shaft with flexible splined couplings. This assembly is installed between the freewheeling adapter flange and the transmission input pinion adapter flange. A spring in each coupling assists in centering of drive shaft during operation.

MAIN DRIVE SHAFT

Transmission Viewed from left side

DRIVE TRAIN

ROTOR BRAKE The rotor brake is attached to the aft coupling of the main drive shaft and used for manually stopping drive train rotation upon shutdown. Engine starts with rotor brake engaged are prohibited. During prestart checks ensure the ROTOR BRAKE handle is Up and Latched. During the shutdown sequence the rotor brake may be applied between 38% and 30% Rotor RPM. Return the handle to the stowed position after main rotor stops.

CAUTION AVOID RAPID ENGAGEMENT OF THE ROTOR BRAKE IF HELICOPTER IS ON ICE OR OTHER SLIPPERY OR LOOSE SURFACE TO PREVENT ROTATION OF HELICOPTER. This is an optional item to the basic aircraft and information on its procedures and limitations may be found in the Supple- ments Section of the Flight Manual.

ROTOR BRAKE

FREEWHEELING ASSEMBLY The freewheeling assembly is mounted on the engine accessory gearbox and its shaft is splined directly to the power takeoff gear shaft. Engine power is transmitted to the outer race of the freewheeling assembly, then through the full- phasing sprag elements of the assembly which couples the engine power to the transmission driveshaft.

The forward tail rotor drive short shaft connects through a flexible coupling to a splined adapter on the aft end of the freewheeling shaft that passes through the engine reduction gearbox During autorotation the main rotor drives the inner race shaft assembly. Under this condition, the freewheeling assembly provides a disconnect from the engine so the rotational forces of the main rotor are free to drive the transmission, tail rotor, and all transmission mounted accessories.

FREE WHEELING UNIT

POWERED AUTOROTATION

FREEWHEELING UNIT

TAIL ROTOR DRIVE SHAFT The tail rotor driveshaft is made up of the following: forward short shaft, the oil cooler fan shaft, the aft short shaft, (5 ea.) identical, interchangeable segments connecting to the tail rotor gearbox. There are seven deep grooved ball bearings supporting these shafts, which require lubricant each 300 flight hrs. Flexible steel disc couplings connect the shaft sections. The forward short shaft and oil cooler fan shaft are made of steel, while the aft short shaft and five segments are constructed of aluminum alloy.

FWD / AFT SHORT SHAFT OIL COOLER FAN SHAFT

DRIVE SHAFT SEGMENTS TAILROTOR GEARBOX