S-61R Pelican/Systems

SECTION 2. SYSTEMS

1 Helicopter

1.1 General

The Shergood S-61R is a twin-turbine engine helicopter designed for transportation of cargo and for search-and-rescue operations in day, night, visual and instrument conditions. The helicopter is powered by two 1,400 shp General Electric T58-GE-10 turbo-shaft engines mounted above the main cabin in front of the main transmission. Drive shafts from each engine is connected to the main transmission through a mixing unit such that the rotors will continue to spin even if one engine fails. When the rotors are not turning, an APU (Auxilary Power Unit) can be used to supply electrical power and hydraulic pressure. Fuel is carried in compartments in the lower hull of the helicopter with forward and aft auxilary and main tanks. An entrance door is located on the forward right side of the main cabin, while a hydraulically powered ramp is in the back. The helicopter is fully amphibious with a "flying boat" style design.

1.2 Gross Weight

The maximum gross weight is 22,050 pounds.

1.3 Pilot-Side Instrument Panel

Figure 1: Pilot-side instrument panel

1. Marker Beacon Intensity	2. RAWS Warning	3. Fire Warning Test	4. Tail-Number plate
5. Marker Beacon Light	6. Fire Warning Light	7. Master Warning Light	8. Torque Indicator
9. Airspeed Indicator	10. Attitude Indicator	11. Radar Altimeter	12. Tri-Needle RPM
13. Vertical Speed Indicator	14. HSI	15. Altimeter	16. AFCS Indicator
17. Turn/Slip Indicator	18. Clock	19. Radio-Magnetic Indicator

1.4 Co-Pilot-Side Instrument Panel

Figure 2: Co-pilot-side instrument panel

1. Master Caution Light	2. Fire Warning Light	3. Marker Beacon Light	4. Tail-Number plate
5. Torque Indicator	6. Airspeed Indicator	7. Attitude Indicator	8. Radar Altimeter
9. Tri-Needle RPM	10. Vertical Speed Indicator	11. HSI	12. Altimeter
13. AFCS Indicator	14. Turn/Slip Indicator	15. Clock	16. Radio-Magnetic Indicator

1.5 Center Instrument Panel

Figure 3: Center instrument panel

1. Fuel Panel	2. N1 Gauge	3. Turbine Inlet Temp (TIT)	4. Fuel Flow
5. Oil Pressure	6. Oil Temp.	7. Trans. Temp & Press.	8. Gear Panel
9. Hydraulic Pressure	10. Warning/Alert Panel	11. GPS Moving Map

1.6 Overhead Panel

Figure 4: Overhead panel

1. Ice Protection	2. Exterior Lighting	3. Windshield Wiper/Wash	4. Rotor Brake Press.
5. Rotor Brake	6. Interior Lighting	7. System Master Switches	8. Electrical Systems
9. Ignition	10. Hoist Cable Shear	11. Fire Protection	12. Start Mode
13. Starter	14. Engine Control	15. Emergency Throttles

1.7 Middle Panel

Figure 5: Middle panel

1. IFF Trasponder	2. GPS Panel	3. #1 NAV Radio	4. #2 NAV Radio
5. Rear Ramp Control	6. Parking Brake	7. Nosewheel Lock	8. Navigation Control
9. Doppler Panel	10. Antenna Control	11. #1 COM Radio	12. #2 COM Radio
13. Emergency Gear Down	14. Fuel Dump Panel	15. AFCS	16. Hydraulic System Select
17. Hoist Control	18. Spotlight Control

1.8 Landing Gear Systems

Figure 6: Landing Gear Panel

The S61 has a tricycle type landing gear system with a nosewheel in front and two main gear in sponsons in the back. The gear is hydraulically actuated through the utility hydraulic system. The system includes a squat switch to prevent accidentally raising the gear while the helicopter is on the ground.

1.8.1 Landing Gear Panel

The landing gear panel (see Figure 6) is located on the center portion of the main console. Three lights on the right-hand side of the panel illuminate green when the respective gear is down and locked. The gear is controlled by a two position lever with a red "in motion" indicator light. The light illuminate when the landing gear are in motion. A test button labeled "HLD LT TEST" can be pressed to test the "in motion" indicator light. Finally, a DN LCK REL button can be used to override the squat switch allowing gear to be raised while on the ground.

Figure 7: Emergency Gear Down Handle

Figure 8: Kneel Switch

Figure 9: Parking Brake and Nosewheel Lock

1.8.2 Landing Gear Malfunctions

Normal wear and tear, or damage through a hard landing can cause the landing gear to malfunctions. Malfunctions may affect retracting, lowering or both. When changing the gear position always verify the red "in-motion" light on the handle comes on, then goes out several seconds later. When lowering gear, always verify you get three green lights indicating the gear is down and locked.

In the event that the gear fails to retract, travel to the next point of landing can be continued, but caution should be used to keep the landing as soft as possible. In the event that gear fails to lower, there is an emergency gear handle (see Figure 7) on the copilot side of the middle console. This handle deploys a compressed air bottle to force the gear into the down position. After use, the air bottle must be replaced before it can be used again. Once the emergency gear extension system is activated, the gear is prevented from retracting until repairs are made to the gear system.

1.8.3 Kneel System

A nose gear kneel switch (see Figure 8) is located on the upper console. This switch is only effective when the landing gear handle is in the down position. Flipping this switch will cause the nose wheel to retract to a 50% retracted position. This can be used to increase the clearance under the tail for loading the helicopter through the ramp. Like the landing gear system, the kneel system requires utility hydraulic pressure to operate.

1.9 Parking Brake

A parking brake (see Figure 9) is located on the pilot side of the middle console. Activating the parking brake will increase resistance to ground movement. Click the handle to toggle its position, or use the chat command:

s brake

to toggle it.

1.10 Nose Wheel Lock

A nosewheel lock (see Figure 9) is located on the pilot side of the middle console just below the parking brake. Activating the parking brake will increase resistance to rotation while on the ground. Click the handle to toggle its position, or use the chat command:

s noselock

to toggle it. The nosewheel lock should be used during rotor engagement to prevent the helicopter from turning on the ground during the high-torque stages of engagement.

2 Emergency Equipment

Figure 10: Engine Fire Detection System

Figure 11: APU Fire Detection System

Figure 12: Engine Warning Test Panel

2.1 Engine Fire Detection System

The S61 is equipped with fire sensors and two fire extinguisher bottles to detect and mitigate engine fires. The fire detection system for the #1 and #2 engines is power by the #1 and #2 AC bus, respectively. The fire detection panel is located on the upper console behind the throttle quadrant (see Figure 10). The panel has two fuel cut-off handles for each engine. The handles will light up when a fire is detected (if AC power is available). Pulling a handle will cut off fuel to an engine through a mechanical linkage.

The fire extinguishers are activate by a 3-position toggle switch between the fuel cut-off handles. The switch will have no effect except when a handle is pulled. This switch should normally be left in the middle OFF position. When deploying an extinguisher, first pull the cut-off handle for the affected engine, then switch the FIRE EXT switch to MAIN. This will deploy the bottle corresponding to the affected engine (#1 bottle for #1 engine, #2 bottle for #2 engine). If a single bottle is insufficient to extinguish a fire, you can switch the FIRE EXT switch to the RESERVE position. This will deploy the bottle from the opposite engine (#2 bottle for #1 engine, or #1 bottle for #2 engine). The fire extinguisher bottles are single use. Once they have been used, they must be replaced on the ground.

2.2 APU Fire Detection System

The APU fire detection panel (see Figure 11) is on the APU panel located on the pilot's side panel. The APU fire detection and mitigation system operates off the DC bus. A warning light will illuminate to indicate a fire has been detected. To activate the fire suppression system, flip the FUEL SHUT OFF switch and FIRE EXTING switches to the forward position.

2.3 Fire Warning Test Panel

A fire warning test panel is located on the pilot side of the main panel (see Figure 12). The panel contains a three-position switch. Flipping the switch to either side from the center position will test the fire detection system and lights for the indicated systems. When the switch is moved to the left marked NO 1 ENG, the fire detection warning light in the Engine #1 fuel cut-off handle will illuminate. When the switch is moved to the right marked NO 2 ENG & APU, the fire detection warning light in the Engine #2 fuel cut-off handle will illuminate, as well as the warning light for the APU.

2.4 Emergency Lights

Emergency lights (see Figure 13) are installed at various positions in the helicopter and provide lights for emergency evacuation in the event of a crash. They are controlled by a three position switch labeled EMER EXIT LIGHTS on the pilot-side of the upper console. In the TEST position, all emergency lights will turn on for testing. In the OFF position, the lights will always remain OFF. In the ARM position (recommended for normal flight), the emergency lights will come on in the event of a sudden acceleration or shock. Once the shock sensor has been tripped, it must be manually reset by clicking on one of the emergency lights in the helicopter.

2.5 Emergency Ramp Release

Figure 13: Emergency Lights

Figure 14: Ramp Release

An emergency ramp release (see Figure 14) is located in the rear of the aircraft on the right side near the ramp. Pulling this lever will release pressure from the hydraulic actuators and allow it to fall by gravity. Return the lever to the up position to reengage the hydraulic actuators and restore normal functioning to the ramp.

3 APU

Figure 15: APU Panel

Figure 16: APU Accumulator Hand Pump

An APU is mounted aft of the main gearbox on the left-hand side of the aircraft. The APU is operated through the APU panel (see Figure 15) located on the pilot's right-side panel. The panel contains a start/mode switch, several warning lights, a tachometer, and a fire suppression sub-panel. The APU can drive the main rotor accessory section to provide hydraulic and AC power without an engine operating. A clutch disengages the APU from the transmission accessory section when the rotor RPM reaches 100%.

3.1 Starting and Stopping the APU

To start the APU, use the following sequence:

1. Turn on the battery.
2. Advance the rocker switch to the RUN position. The LOW OIL PRESS and HIGH EXH TEMP lights will illuminate.
3. Press and hold the rocker in the START position until the RPM gauge reads at least 40%. The LOW OIL PRESS and HIGH EXH TEMP lights will go out as the APU RPM exceeds 20%.
4. The RPM will continue to increase automatically. Between 70% and 78%, the rate of increase will slow while the APU clutch engages.

To stop the APU, simply move the rocker switch to the OFF position.

3.2 APU Accumulator

While electrical power is needed for the APU controller during startup, a hydraulic accumulator is used to actually spin up the APU turbine during start. The accumulator is mounted behind the main transmission on the right-hand side of the aircraft. An APU accumulator hand pump is mounted in the main cabin on the right-side wall behind the troop seats. If the accumulator pressure reads below 3000 psi, then the pump should be actuated by hand to recharge the accumulator. In normal operation, the accumulator will be recharged automatically from the utility hydraulic system. However, if the utility hydraulic system has failed, or the APU start sequence is started but aborted before completing the start, the accumulator pressure may fall too low to start the APU. APU starts at extremely low outside air temperatures may require higher accumulator pressures for successful start.

3.3 Warning Lights

Light	Description
PRI PUMP PRESS	Indicates lack of fuel pressure from the priming pump. Could indicate damage to the APU.
LOW OIL PRESS	APU oil pressure is too low.
HIGH EXH TEMP	APU exhaust temperature is too high.
OVERSPEED	APU speed is too high. Could indicate failure of the clutch to disengage when main rotors spin up to 100%.
FIRE	Indicates a fire detected in the APU.

3.4 APU Fire Detection and Suppression System

The bottom portion of the APU control panel is the APU fire detection and suppression system. A "FIRE" warning indicator on the panel will illuminate when an APU fire has been detected. The emergency fuel cut-off switch will cut off fuel to the APU through a solenoid value. A switch labeled FIRE EXTING will deploy the APU fire extinguisher. The APU fire extinguisher is separate from the extinguishers for the main engine. Once deployed, the fire extinguisher bottle must be replaced before the system can be used again.

4 Engines and Related Systems

4.1 General

Figure 17: Pelican engine controls overlay.

The S61-R is powered by two General Electric T58-GE-10 turboshaft engines delivering 1,400 shp each. The engines are mounted above the main cabin in front of the main transmission.

4.2 Engine Control Levers

Engine control levers and emergency throttles are located on the forward overhead panel between the pilot and copilot seats. In normal operation, only the yellow engine control levers are used. To operate the levers, click in the general area of the lever to bring up the control overlay (see Figure 17). Once the overlay is active, clicking on one of the scales will move the lever under it to the selected position. To dismiss the control overlay, you can click the "X".

The blue scales in the center part of the overlay are used for the engine control levers. Clicking on one of the one of the wide blue scales will move the lever under it to the selected position. There are stops at "SHUT OFF", "GRD IDLE" (ground idle) and "MIN GOV" (minimum governed) positions. Above "MIN GOV", the engine control lever is analog and can be placed at any position to operate the engine at a specific RPM. A "100% SPEED" marking shows the approximate position for 100% RPM. In normal operations, RPM should be between 90% and 110%.

Next to each engine scale is a narrower "trim" scale. Clicking on the trim scale will nudge the engine control in the indicated direction relative to the center point. The further you click from the center point of the scale, the larger the nudge will be.

Between the two throttles is a paired scale. Clicking on this scale will move both engine control levers to the indicated position.

The engine control levers do not directly control the throttles on the engine. Instead they command a fuel controller to maintain a specific RPM. As the load on the engine is increased, the throttle is opened to maintain that RPM.

4.3 Emergency Throttle Levers

Figure 18: Ignition Switches

On the outside of the engine control quadrant are two emergency throttle levers. In normal operation, they are left in the CLOSED position. In the event of a fuel controller failure, the throttle will "stick" in its position when the controller failed. The emergency throttle levers have a mechanical linkage that allows them to open the throttle beyond the point where it failed, but the throttle cannot be closed through use of the emergency throttles. In practice, the first part of travel of the emergency control lever will have no effect until it is opened beyond the point of the stuck position.

When using an emergency throttle in flight, care should be taken to make collective movements as slow and gradual as possible to avoid overspeeding the engine. Adjustments to the collective or an emergency throttle should always be done while monitoring engine and rotor rpm.

To move an emergency throttle, click on one of the red scales of the engine control overlay. The large scales move the throttle to the selected position, while the smaller scales next to it are for trim, nudging the throttle in the indicated direction.

4.4 Ignition System

Ignition switches are located on the lower left side of the upper console. There is one three position rocker switch for each engine. The ignition system is powered by the DC bus. In the center OFF position, the engine igniters are deenergized. A spring-loaded TEST position for each rocker can be used to test the igniters. When held in the TEST position with DC power active, a clicking sound will be heard. The igniters should never be tested except when the engine control levers are in the SHUT OFF position, the starters are not running, and the engine fuel values are closed. In the NORM position, the igniters will activate while the starter is running. This position should be used for normal start and while engine is operating.

WARNING: Do not advance engine control levers out of SHUT OFF with the igniters active until N2 is above 20%.

4.5 Starter System

Figure 19: Starter Switch

Figure 20: Start Mode

Each engine is equipped with an electric starter powered by the DC Bus. The starter is activated by a three-position rocker switch on the upper console, one for each engine (see Figure 19). To engage the starter, momentarily move the switch to the START position. The switch is spring loaded an will return to the center position, but the starter will continue to run. The starter will turn the compressor stage (N1) of the engine up to 26% to allow normal flow of fuel and air for an engine start. Pressing the ABORT side of the starter switch will disengage the starter motor.

When the start mode switch (see Figure 20) is in the NORMAL position, the starter will automatically dropout when N1 exceeds 35% as the engine spins up during start. Placing the start mode switch in the MANUAL position will disable this behavior.

The electrical field from the starter motor will cause a change in the heading indicated on the magnetic compass. For this reason, it is suggested that the crew note the magnetic compass heading before engaging the starter so that they can confirm the starter dropout occurs at 35% N1. This change in the compass is the only way to know that starter dropout has occurred.

4.6 Primary Engine Instruments

Gauge	Description
	N2 - The speed of the power turbine in percent RPM. This is the speed of the main drive shaft connecting the engine to the main transmission. There is a numbered needle for each engine's N2 speed, and an additional needle marked R for the rotor rpm.
	Torque - Torque produced by the engine. Each needle is marked with an engine number. At operating RPM, this gauge represents the amount of power being produced by the engine.

4.7 Secondary Engine Instruments

Gauge	Description
	N1 - Speed of the engine compressor stage. As the name suggests, the compressor serves to compress air coming into the combustion chamber. The speed of the compressor will vary with the amount of power being produced by the engine.
	Turbine Inlet Temperature (TIT) - The temperature of the exhaust gases from the combustion chamber as the enter the turbine.
	Oil Pressure - Pressure in psi of the engine oil system.
	Oil Temperature - Temperature in degrees Celsius of the engine oil in the sump.

4.8 Engine Warnings/Alerts

The warning/alert panel includes alert lights #1 ENG OIL QTY LOW and #2 ENG OIL QTY LOW that indicate when the oil level in the engine is low. Upon seeing this alert, flight can be continued to the next planned destination, but oil should be added to the system before continued flight.

4.9 Engine Operating Limitations

TBD

5 Fuel System

Figure 21: Fuel System

5.1 Fuel System Overview

The S61R has two independent pressure-type fuel systems (see Figure 21) joined with a crossfeed connection. Each system (forward and aft) consists of a main tank and an auxiliary tank (four total tanks). The forward system feeds the #1 engine, while the aft system feeds the #2 engine. Boost pumps and transfer valves can be used to transfer fuel from the auxiliary to the main tanks. Each system has two boost pumps submerged in the main tank, and a third unboosted feed line. The engines also contain their own engine-driven fuel pump which can draw fuel on its own from the main tanks. An electrically operated crossfeed valve can be opened to allow crossfeed of fuel from one system to the opposite engine.

5.2 Fuel Tanks

The S61R is equipped is equipped with the following four fuel tanks having the following capacities:

Tank	Capacity	Feeds
Forward Tank	348 gal.	Feeds #1 engine
Aft Tank	345 gal.	Feeds #2 engine
Forward Aux Tank	184 gal.	Feeds Forward and Aft tanks
Aft Aux Tank	245 gal.	Feeds Aft Tank

Each fuel tank can be refueled using either a gravity filler or through the pressure refueling system.

5.3 Fuel Type

The S61R is designed to operate on JP-5 or JET-A fuel. When refueling with KellyFuel 3.0 or later, care must be taken to use the correct fuel type. If the incorrect fuel type is used, the fuel in that tank will be tainted, and operating the engine with tainted fuel will cause engine damage. If a tank is accidentally filled with the wrong type of fuel, the tank must be completely emptied to flush it of all contaminant. The tanks can be flushed either using the fuel dump system, or through the @Cheat menus.

5.4 Fuel Booster Pumps

Two fuel booster pumps are located in each main tank. The booster pumps are located in a collector can located in each tank. As fuel is pumped to the main engine, it is also pumped back to the main tank through an ejector unit to ensure the collector can remains full. Ejector units in the auxiliary tanks, which are activated by opening an electrically controlled valve, allow the boost pumps to transfer fuel to the main tanks.

The pumps for each tank use a different power source. In the forward system, the No 1 boost pump is powered by the #1 AC bus, and the No 2 boost pump is powered by the #1 AC Monitor Bus. In the aft system, the No 1 boost pump is powered by the #2 AC bus, and the No 2 boost pump is powered by the #2 AC Monitor Bus.

The pumps are controlled by switches on the fuel system control panel. Each pump has a low pressure indicating light above it. The indicator light is active only then the pump switch is turned on. When turning on a pump, the indicator light should flicker briefly, then go out. If the low pressure warning light remains on, it indicates the pump has failed, or is not receiving AC power from the appropriate system.

Engine may be operated with one, both or no boost pumps. However, boost pumps must be used in the following conditions:

• Above 6000 feet MSL.
• While dumping fuel
• Above 43 degrees C
• While transferring fuel
• When below 600 pounds of fuel per tank.
• Whenever a fuel filter by-pass light is illuminated
• One pump per tank during takeoff and landing
• During crossfeed operations

Note: Continuous operation of at least one boost pump per engine is recommended to prevent inadvertent operation of the aircraft during one of the above conditions.

5.5 Fuel System Control Panel

Figure 22: Fuel Control Panel

The fuel system is controlled through a fuel management panel (see Figure 22) mounted in the center portion of the main control panel.

5.5.1 Fuel Gauges

Fuel gauges for each tank are located on the center of the fuel management panel. From top to bottom the gauges are for the forward auxiliary, forward main, aft auxiliary and aft main tanks. The forward main, and aft auxiliary tank fuel gauges are powered by the #1 AC Bus, while the aft main and forward auxiliary gauges are powered by the #2 AC Bus.

5.5.2 Fuel Gauge Test Button

A red fuel gauge test button is located in the lower left corner of the fuel management panel. Press and hold this button cause all four gauges to go to a zero reading. Releasing the button will cause the gauges to return to the actual reading if they are powered and functioning correctly.

5.5.3 Fuel Shutoff Switches

At the top of the panel are two fuel shutoff valves. The shutoff switches are located below the NO 1 ENG and NO 2 ENG labels and operate electrically controlled shutoff valves.

5.5.4 Low pressure warning lights

Below the shutoff switches are two low pressure lights. The lights will illuminate when there is inadequate fuel pressure to their respective systems.

5.5.5 Boost Pump Switches

A pair of boost pump switches along with their associated low-pressure warning lights are located on each side of the fuel tank gauges. The switches on the left side are for the forward system, while the switches on the right side are for the aft system.

5.5.6 Fuel Transfer Switches

Two fuel transfer switches are located to the right of the fuel gauges. The transfer switches operate an electrically controlled valve that allows the boost pump for the tank to which fuel is flowing to force fuel from the selected auxiliary tank into that main tank. The top fuel transfer switch is three-position and can be set to transfer fuel from either the forward auxiliary to the forward main tank. The lower fuel transfer switch can be set to transfer fuel from the aft auxiliary tank to the aft main tank.

5.5.7 Crossfeed Switch

In the top center of the fuel management panel is the crossfeed switch. This switch controls an electrically controlled crossfeed valve. This switch can be used to feed an engine from the opposite fuel system. The boost pumps from the system feeding the opposite engine must be on when conducting crossfeed operations.

5.6 Low Fuel Caution Lights

The low fuel caution lights FWD FUEL LOW and AFT FUEL LOW are located on the caution and advisory panel on the main control panel. These lights will illuminate when 170-280 pounds remain in the respective main tanks. The caution lights operate off DC power. When a light illuminates, it is recommended that the pilot land as soon as practicable to refuel, or that fuel be transferred from the auxiliary tanks. Prolonged operation with a blocked filter is not recommended as it will allow unfiltered fuel to flow through the fuel control and engine, leading to possible damage to those components.

5.7 Fuel Filters

Each fuel system includes a fuel filter before the fuel is passed to the engine. The fuel filters filter contaminants from the fuel before passing into the engine. Each fuel filter includes a spring-loaded bypass valve. When the filters reach a certain level of blockage from contaminants, back-pressure from the filters will cause the valves to open, and fuel to flow around the filters.

5.7.1 Fuel Filter By-Pass Caution Lights

The fuel-filter by pass caution lights marked FWD FUEL BY-PASS and AFT FUEL BY-PASS are located on the caution and advisory panel on the main control panel. The caution lights illuminate when the fuel filter by-pass value in the respective system is open and fuel is by-passing the fuel filter. This light indicates blockage in the fuel filter and that the filter should be replaced.

5.8 Gravity Refueling

Figure 23: Gravity Refueling Ports

Gravity refueling ports are located on the left side of the aircraft in front of the left sponson. The forward auxiliary and tank fillers are located behind separate panel doors, while the aft auxiliary and main tank fillers are located behind a shared panel door. To refuel a tank through the gravity refuel system, the panel door must be open and the tank cap must be removed by clicking on them. Tanks can be filled using either KellyFuel or by using the "refuel" chat command.

The front strut can be used as a ground point while refueling. Always properly ground your aircraft before fueling to avoid a static discharge from sparking a potential fuel fire.

5.9 Pressure Refueling

Figure 24: Pressure Refueling Port

The pressure refueling port behind a panel door on the right side of the aircraft below the main cabin door. Open the panel door and undo the cap on the fuel port to prepare for fueling. Pressure refueling can be used to more rapidly refuel all tanks of the aircraft at once. Fuel flow rate while pressure refueling is approximately 10 times the rate as with gravity refueling. The pressure refueling system is compatible with KellyFuel. You can also use the "refuel" chat command while a cap is open.

The front strut can be used as a ground point while using the pressure refueling system. Always properly ground your aircraft before fueling to avoid a static discharge from sparking a potential fuel fire.

5.10 Fuel Dumping

Figure 25: Fuel Dump Control Panel

The S61 is equipped by a fuel dump system to dump fuel in flight from the main tanks. The dump system is controlled through the fuel dump control panel shown in Figure 25. The fuel dump switches control electric gate valves located off the fuel line ahead of the fuel filter. When conducting a dump, at least one boost pump in the target tank must be operating. Fuel can only be dumped from the main tanks. To dump fuel from an auxiliary tank, the fuel must first be transferred from the auxiliary to the main tank. Dumped fuel is expelled through a tube located at the back of the right sponson. The dump system is capable of dumping 140 pounds/min from each side.

5.11 Fuel Drain Ports

Figure 26: Fuel Drain Port Locations

There are 8 fuel drain ports on the underside of the aircraft: one for each auxiliary tank, two for each main tain, and one for each fuel filter. The drain ports should be checked before each flight to ensure the fuel is contaminant free. Drained fuel should be clear and have an oily smell. If there is a blue or red tint to the fuel, do not fly or start the engines. A blue or red tint indicates that the tank is contaminated with aviation gasoline. If contaminated fuel is found, the tank should be flushed before the next flight.

6 Flight Controls and AFCS

6.1 Flight Controls

The helicopter is controlled by changing the pitch of the blades collectively or cyclically. Pitch changes are made through the flight controls which include a collective, a cyclic control stick and anti-torque pedals. The pilot and copilot controls are interconnected and move together. The collective increases the pitch of all blades, controlling the helicopter vertically. The anti-torque pedals control the pitch of the tail rotor, thus changing the tail rotor thrust. The cyclic imparts unequal pitch around the blade disk to redirect thrust laterally or longitudinally. See SECTION 1 - General for details on the Second-Life control options for the controls.

6.2 AFCS

Figure 27: AFCS Control Panel

The Advanced Flight Control System (AFCS) can be used to reduce pilot workload by maintaining one or more flight axes of the helicopter. It can be used to maintain airspeed, heading, altitude or any combination of these. The system is comprised of an AFCS computer, a doppler radar system, sensors, channel monitor, an afcs indicator, actuators and a common AFCS control panel (see )

At the top of the AFCS panel are four "hold" buttons. Turning on a hold causes the selected flight axis to be maintained automatically by the AFCS. The following four holds can be maintained:

Button	Effect
HDG	Holds heading. Below 40 knots, heading will be maintained with pedals, and above 40 knots with lateral cyclic. When enaged, the current heading will be held. You can change the heading either through chat command, or by turning the heading bug on the HSI.
IAS	Holds the Indicated Airspeed you were maintaining when the button was engaged. The held airspeed can be changed through chat commands.
BARO ALT	Holds the barometric altitude (above MSL) at the time you engaged the hold. Target altitude can be changed through chat commands.
RAD ALT	Holds the radar altitude (above ground level) at the time you engaged the hold. Radar altitude can only be used to the limit of the radar altimeter. Target altitude can be changed through chat commands.

In addition to the hold buttons is an AUTOHOVER button at the bottom of the AFCS panel. Engaging AUTOHOVER will set holds on heading, airspeed and altitude and set the hold airspeed to zero. Pressing AUTOHOVER again while already in an autohover will disengage the autotpilot.

6.3 AFCS Chat Commands

he following chat commands can be used with the AFCS:

Command	Description
ap IAS	Toggle airspeed hold
ap ALT	Toggle altitude hold
ap RALT	Toggle radar altitude hold
ap HDG	Toggle heading hold
ap HVR	Enter autohover mode
ap DIS	Disconnect autopilot
ap IAS n	Set the target airspeed to n
ap HDG n	Set the target heading to n
ap L n	Set the target heading left by n degrees
ap R n	Set the target heading right by n degrees
ap ALT n	Set the target altitude to n feet
ap RALT n	Set the target altitude to n feet above ground
ap D n	Set target altitude up n feet
ap U n	Set target altitude down n feet
ap to	Take off to a low hover then enter autohover
ap land	Autoland aircraft.

6.4 AFCS Indicator

Figure 28: AFCS Indicator

An AFCS indicator gauge (see Figure 28) is mounted on the pilot and co-pilot sides of the main instrument panel. The gauge takes input from the AFCS and displays any movement of the helicopter from a stable hover. The AFCS and doppeler radar systems must be on for the AFCS indicator to function, but the AFCS does not need to be engaged. The vertical and horizontal needles show lateral and longitudinal movement relative to the ground, respectively. When the needles are centered, there is no lateral or longitudinal movement of the helicopter. The more the deflection of each needle, the higher the ground movement is. When a needle is deflected, the cyclic must be moved in the direction of the needle to stop movement of the helicopter.

The triangle indicator on the bottom of the indicatorwith a horizontal scale shows yaw motion. The more the triangle is deflected from the center, the faster the the yaw motion of the helicopter. Press the anti-torque pedal opposite the arrow deflection to stop yaw motion and center arrow.

The triangle indicator on the left side of the indicator with the vertical scale reflects vertical motion of the helicopter. The amount of deflection indicates he amount of vertical movement. Apply collective in the opposite direction of the deflection to recenter the needle and stop vertical movement.

6.5 Channel Monitor Panel

Figure 29: Channel Monitor Panel

The AFCS outputs commands on four channels: pitch (longitudinal cyclic), roll (lateral cyclic), collective and yaw. The channel monitor panel (see Figure 29, located on the pilot's side console, modulates these outputs and allows information on one or more channels to be disabled in the event of a partial AFCS failure. In normal operation, the channel switches at the top of the panel should all be left in the ON position. Moving a switch to the OFF position will disable output from the AFCS on the indicated channel.

Each channel also has a three-position hardover switch. These switches are normally left in the center OFF position. Moving a hardover switch forward or back will force output on the AFCS channel in the indicated direction.

A channel monitor test switch, located on the upper panel, can be used to test the channel monitor. When the AFCS is on, and the channel monitor test switch is in TEST mode, the control output on each channel will cycle back and forth slowly over a small displacement. Turnning off a channel switch will stop movement on the affected channel.

The channel monitor panel also includes a switch labeled VERTICAL GYRO. The vertical gyro is used to send pitch and roll information to the AFCS. The helicopter is equipped with a port and a starboard gyro. In the event one of these gyros fail, use this switch to select the other gyro.

A METER SELECTOR knob can be used to select the information that is displayed on the AFCS indicator. In normal operation only the ASE position should be used.

6.6 Doppler

Figure 30: Doppler Radar Control Panel

The autopilot/AFCS gets its lateral movement information through a doppler radar system. The doppler system is controlled by a panel (see Figure 30) on the middle console. A green indicator light on the doppler panel shows when the system is powered and functioning. In additional the doppler system has the following four switches:

Switch	Description
ON/OFF	Turns the unit on and off.
INCR/DECR	Test switch for longitudinal motion sensing. When in the INCR or DECR positions, a constant "forward motion" or "backward motion" signal will be sent to the AFCS. In normal operation this switch should be in the center position.
LEFT/RIGHT	Test switch for lateral motion sensing. When in the LEFT or RIGHT positions, a constant "left motion" or "right motion" signal will be sent to the AFCS. In normal operation this switch should be in the center position.
LAND/SEA	This switch controls the sensing mode of the doppler system. When LAND is selecting, motion sensing is optimized for land operation. When SEA is selected, motion sensing is optimized for over-water operations. If the switch position does not correspond to the type of surface the helicopter is flying over, AFCS hover performance over that surface will be degraded.

7 Hydraulic Systems

Figure 31: Hydraulic Pressure Gauges

Figure 32: Primary and Auxiliary Hydraulic Systems

7.1 General

The S-61R has two flight control hydraulic systems (primary and auxiliary) and a utility hydraulic system. All hydraulic pumps are powered by the main transmission accessory drive which is powered by either engine or by the APU. Engine and/or APU must be at above 70% RPM for hydraulic pressure to be available. A bank of three pressure gauges shows the pressure of each system (see Figure 31).

7.2 Flight Control Hydraulics

The primary and auxiliary hydraulic systems (see Figure 32) provide boost power to operate the flight controls. The flight servos also limit feedback of vibration in the rotor system to the flight controls. These act in conjunction with the direct linkages from the flight controls to the swash plate to reduce the forces needed to actuate the controls. Each system operates independently and operates a similar set of servos. In normal operation, both systems are in use during flight, but a switch on the collective can be used to disable either system in the event of a hydraulic failure on one of the systems.

7.2.1 Primary Hydraulic System

The primary hydraulic system powers three hydraulic servo units that control the main rotor swash plate for cyclic and collective control inputs. The primary hydraulic system does not provide any boost or damping for the anti-torque pedals. A low pressure sensor detects when the hydraulic pressure is inadequate and illuminates a PRI-HYD PRESS warning light on the warnings and alerts panel. A pressure gauge on the main panel also shows the pressure available in the system. The primary hydraulic system is feed by a 0.45 gallon reservoir located in the rear portion of the engine and transmission compartment.

7.2.2 Auxiliary Hydraulic System

The auxiliary hydraulic system powers four hydraulic servo units, three that control the main rotor swash plate for cyclic and collective control inputs, and a fourth servo unit driving the anti-torque pedals. The auxiliary system also handles cyclic trim and the AFCS. A low pressure sensor detects when the hydraulic pressure is inadequate and illuminates a AUX-HYD PRESS warning light on the warnings and alerts panel. A pressure gauge on the main panel also shows the pressure available in the system. The auxiliary hydraulic system is feed by a 0.45 gallon reservoir located in the rear portion of the engine and transmission compartment. Note that the auxiliary hydraulic system must be functioning for AFCS use.

When the auxiliary hydraulic system is active, and the STICK TRIM MASTER switch on the overhead console is ON, the following fine control chat commands are enabled:

Command	Description
fc	Toggles fine control on/off.
fc0	Turns off fine control.
fc1	Turns on fine control.
fc2	Turns on very fine control.

7.3 Utility Hydraulic System

Figure 33: Utility Hydraulic System

The utility hydraulic system (see Figure 33) provides pressure to all hydraulic systems other than the flight controls. A 3000psi pump drives the system. Hydraulic fluid is held in a 5.03 quart reservoir located in the aft of the engine and transmission compartment. A pressure indicator in the cockpit (see Figure 31) indicates the current pressure in the system.

The utility hydraulic system provides pressure for the following systems:

• Landing gear
• Ramp
• Hoist
• Cargo hook
• APU starter/accumulator

8 Power Train System

Engine power is supplied to the rotors through a mechanical transmission system. This system consists of a main transmission, and intermediate and tail rotor gear boxes. An overruning sprag clutch for each engine in the main transmission allows the rotor system to continue turning in the event of an engine failure. The main transmission includes an accessory section which drives the hydraulic pumps and generators; and a main drive section which drives the main rotors. An output shaft from the main rotor drives an intermediate gearbox at the base of the tail, which in turn drives a tail rotor gearbox at the top of the tail which ultimately drives the tail rotor.

The transmission can be monitored from the cockpit through pressure and temperature gauges as well as alert lights indicating when tolerances are exceeded. The main transmission temperature and pressure gauges are mounted on the center portion of the main panel (see Figure 3, Item 6). Each transmission system includes a chip detector. The chip detector consists of two magnetized electrodes. Any metal particles in the lubrication system will collect on the electrodes and bridge the gap forming an electrical connection. This will a trigger the chip warning light on the warning and alert panel in the cockpit. The chip lights are XMSN CHIP MAIN, XMSN CHIP INTMED and XMSN CHIP TAIL for the main, intermediate and tail-rotor transmissions, respectively. The main transmission also has two additional warning lights for the main transmission oil temperature and pressure, XMSN OIL HOT and XMSN OIL PRESS.

9 Rotor System

Lift is produced by a single counter-clockwise rotating main rotor with five blades. A five blade tail rotor produces thrust for yaw and to counter-act torque from the main rotor. Rotor RPM is displayed on a tachometer (in percent RPM) on the pilot and copilot sides of the console along with the engine RPM (see Figure 1, Item 12).

9.1 Inflight Blade Inspection System

The main rotor blades are equipped with an Inflight Blade Inspection System - IBIS, this system alerts the pilot to damage to the rotor blades that may signal an impending failure of the rotor system. IBIS consists of pressurized main rotor blades, a trip mechanism at the root of each main rotor blade, a detector on the aircraft and a BLADE PRESS warning light on the caution light panel. In the event of any damage to a rotor blade, such as cracks in the blade, the blade will depressurize, activating the trip mechanism. The trip mechanism then exposes a tiny radioactive source that is detected by the detector on the aircraft, which then illuminates the BLADE PRESS warning light. In the event the BLADE PRESS warning light illuminates, an immediate landing should be made.

10 Electrical System

Figure 34: Electrical Systems

Figure 35: Electrical Panel

Figure 36: External Power Port

10.1 Overview

The S-61R electrical system (see Figure 34) consists of two AC buses, two AC monitor buses, a DC bus, and a hot battery bus. Each AC bus is powered by a 115V, 400 Hz generator. The AC buses are connected by current limiters. In normal operation, both buses can be powered by either generator, but in the event of a short on one of the buses, the current limiters will allow the other bus to continue to function normally. Connected to each AC bus though a relay is a monitor bus. A control circuit will disconnect both monitor buses unless both AC generators are producing power. If either generator is off, damaged, or there is a short on one of the AC buses, the monitor buses will disconnect.

The DC system operates at 28 volts when powered through converters from either AC bus, or from a 24-volt nickel-cadmium battery. The hot battery bus supplies power to several devices even when the BATT switch is OFF. These devices include the digital clock and the anchor light.

The table below summarizes the electrical buses in the S-61R:

Bus	Powered By
Battery Hot Bus	Battery (At all times)
DC Bus	DC Converters 1 & 2 or Battery (with battery switch on)
#1 AC Bus	#1 Generator (#2 will power if #1 fails)
#2 AC Bus	#2 Generator (#1 will power if #2 Fails)
#1 AC Monitor Bus	#1 AC Bus (Dropped if either generator fails)
#2 AC Monitor Bus	#2 AC Bus (Dropped if either generator Fails)

10.2 Electrical Panel

The electrical system is controlled through a set of 6 switches on the overhead panel (see Figure 35). A switch labeled BATTERY energizes the DC bus from the battery when turned ON.

Switch	Description
BATTERY	Energizes the DC bus from the 28V DC battery
GEN1/GEN2	Enables the generators for each AC bus. The main transmission accessory section must be powered by an engine or the APU for the generators to produce power.
CONV1/CONV2	Energizes the DC bus by converting power from an AC bus
EXT PWR	Enables external power to all buses.

10.3 External Power

An external power port is located at the front of the aircraft on the right-hand side (see Figure 36). A Ground Power Unit (GPU) can be connected to this port to provide DC and AC power on the aircraft. In addition to connecting the ground power unit, the EXT PWR switch in the cockpit must also be ON in order for external power to be available in the aircraft. To recharge the battery, the BATTERY switch must also be on. When external power is connected and turned on a green EXT PWR advisory light will illuminate in the cockpit.

11 Utility Systems

Figure 37: Ice Protection

11.1 Ice Protection

Ice protection systems are controlled through a panel on the overhead console (see Figure 37). These systems are described in the following sections.

11.1.1 Engine Anti-Ice

The engine anti-ice systems is comprised of a set of sensors and heaters in each engine inlet. The purpose of the system is to prevent ice from forming at the engine inlets and possibly being ingested by them. When the anti-ice system is engaged, the #1/#2 ENG-IVE ANTI-ICE advisory light for the affected engine will illuminate. Also, while the anti-ice system is engaged, and the inlet temperature is below 38C, the #1/#2 INLET ANTI-ICE warning light will illuminate. When first turning on the anti-ice switch, the #1/#2 INLET ANTI-ICE warning light may illuminate until the inlet surface temperatures warm up above 38C. It is also possible for the #1/#2 INLET ANTI-ICE warning lights to come on in extremely cold temperatures if the inlet surfaces cannot be warmed above 38C.