Preflight the TH-57

Aircraft

1. Aircraft....... Check general condition:

FOD Puddles from leaks Listing of the mast Ties removed Unsecured panels Smiling Helo (bent cross tube for the skids indicating a hard landing) General condition. Check for damage, un-repaired cracks, and cleanliness

Note: It will not be mentioned again that you are responsible for ensuring that all castellated nuts are cotterkeyed, noting warped metal and looking for popped rivets. Furthermore, slip marks should be aligned. Key safety wiring is mentioned, however, ensure that wiring not mentioned is gainfully employed.

2. Battery and battery compartment - Connections, mounting, vent lines, hour meter, circuit breaker.

Battery counter and circuit breaker - condition and ensure the breaker located on the back wall of the battery compartment is in. Battery vent (air in) and drain (air out) - connected. The two tubes on the top of the battery. Battery - condition, security and connection This is a 24-volt, 17-amp hour sealed lead-acid battery (SLAB). There are two sensors located under the battery that connect to the caution panel. Sensing of a temperature 54 +/- 3 degrees Celsius will illuminate the BATTERY TEMP light and temperature 60+/- 3 degrees Celsius will illuminate the BATTERY HOT light. Lights will extinguish in the event that temp falls below warning level (n 2-22). The connector arm is vertical when correctly connected. As of 30 Aug 2006 the last of the new SLABs was installed and so the NiCad that is referenced in the Systems Pub is gone. A couple of notes from maintenance personnel are interesting regarding this new battery: 1) because it is a "sealed" battery the vent and drain lines are not used by the battery. They are, however, continually maintained as per FAA guidelines. 2) also because this is a "sealed" type battery, the temperature sensor that triggers the BAT HOT and BAT TEMP caution lights is rendered useless. Relays - connection and condition The two identical, oval shaped objects in front of the battery. The one closest to the battery is the battery relay and the other is the APU relay. Switching the battery on energizes the BATTERY relay thereby connecting the battery to the DC common bus. The same logic is applied to a connected APU w/power applied. General-purpose diode - condition In the front of compartment, on the service deck, there is a small (about 1.5 inches) protruding object. This is a for polarization protection (maintenance personnel). Battery door - security

Front Section

1. Free-air temperature bulb - security Located atop the windshield a 2-3 inch silver cylinder is visible just to the pilot's side of center. This is a bimetal, free-air temperature indicator that displays temperature reading in Celsius and Fahrenheit (n 2-40). 2. Windshields - Cleanliness, Condition 3. Battery Compartment access door - Condition and Security. 4. Pitot tube - Cover Removed/Unobstructed Ensure the word "TOP" is in fact on top. As with all pitot tubes there is one hole in front and a smaller one underneath. Check both. 5. APU receptacle and door - Condition and Security. Located directly below the battery access panel 6. Ram air ducts - Free of Obstructions. Grills in the nose on either side of the battery access panel Two push/pull cables on either side of the center console control the ventilation system. These intakes direct air to a manifold assembly that in turn provides air to the defog system or direct cabin air ventilation. The starboard duct air runs to a fan which sits on top of a second air conditioner evaporator located directly beneath it. This evaporator is not mentioned in NATOPS or the Systems book but there it is, big as life. Ram air drains (one on each side) - check condition- These drains protrude from the chin bubble and tubing connecting the drains and the ram air vents is visible through the chin bubble. These drains provide an outlet for water taken in ram air vents during inclement weather. Note the starboard drain tube has an additional connection, this is a condensation drain from the evaporator. 7.Searchlight - cleanliness, security Located under the fuselage, just aft of the nose. The on/off/stow switch controls the searchlight as well as a directional control switch located on the pilot's collective. The searchlight system is protected by two circuit breakers located on the overhead panel, one for the power and one for the control. The light is adjustable to 120 degrees of extension. From 0 to 60 degrees extension, the light will rotate 90 degrees left or right. From 60 to 120 degrees the light will rotate 360 degrees. (n 2-41) While you are here check the Pitot and static drains - security They are located on the starboard side of the searchlight. Pitot is on the port side and static is on the starboard side (they are labeled). 8. Landing light - Cleanliness and Security. This light will illuminate the area beneath the helicopter for hovering operations. It is protected by a circuit breaker that is integral to the LDG LT switch. CAUTION: Excessive use of the landing light (10 minutes or more during periods of prolonged hovering or taxiing) may cause overheating with a resultant fire hazard. The landing light is not often used in landing because the searchlight points forward and is easier for ground personnel to see. However, the landing light is sometimes used to signal a hot seat to enter or depart the rotor arc, because the light is indirect and will not blind them as the spot would. 9. Battery vent/drain - free of obstructions Located on the port side of the searchlight. Remember that vents face fore and drains face aft. These connect to the top of the battery. 10. Instrument panel console vent screen - free of obstructions Located under fuselage in aft of the searchlight. 11. Chin bubbles, pedals - FOD Condition and Security Since you are looking at the pedals through the chin bubble, make a point to look for cotterkeys as well.

Cockpit

1. All Switches - off (in the aft position) Five switches may remain on: Hydraulic Boost, Force Trim, the Fuel Valve, and Comm 1 and 2 for each radio. (don't forget to ensure searchlight is off) 2. Twist grip - Check and closed (check full travel, no binding, idle detent) Twist the grip to the full open position, swiftly bring back to flight idle to ensure the idle detent prevents securing the engine, then, by pressing the idle release button, fully close the twist grip. 3. Circuit breakers - In       Do not forget ENC and TQ on the lower consul. ENC corresponds to the mode C function of the transponder and TQ is for the digital display on the torquemeter (C) 4.Voltmeter select switch - MAIN BAT 5. BAT switch - ON. Check minimum 24 Vdc 24-volts minimum for battery start 17 volts minimum for APU start 6. Torquemeter and TOT gauges - check the digital displays to ensure that no limits have been exceeded overtorque/overtemp -- The digital display will read as such: _O_E flashing twice per second followed by the previous Max torque reading and duration in seconds. More guidance on what information the digital displays of the torquemeter and TOT gauge provide on power up can be found in NATOPS 2-4. (C) 7.STBY ATT IND switch - ON. 8. Caution lights - Check (T.H.E.R.G.(S)) and no CHIP Lights. The caution panel is powered by the essential No. 2 bus in the Charlie model and in both models is protected by the CAUTION LT circuit breaker T. Transmission oil pressure H. Hydraulic pressure E. Engine out R. Rotor low RPM G. Generator failure S. (C) STBY GEN FAIL 9. Fuel quantity gauge - Note Fuel Quantity 76 gallons max for old bravo models (161xxx) and 91 gallons max for all others. These are maximums, you will be checking for an indication in line with your weight and balance sheet requirements/limitations. 65 is normal for FAMs. 10. Airframe fuel filter button - test. Check A/F fuel filter caution light illuminates. The A/F fuel filter button is at the 7 o'clock position on top of the fuel filter (inside starboard engine cowling). If you are alone you can leave the battery on and press the button yourself and look through the window for caution light illumination. If with a partner one person can press the button and the other can look. 11. Chip Detector System Power Unit - Check all lights extinguished This is also in the rear cabin by the comm box on the starboard side. Lift the lid and ensure that, with the battery on the lights remain off. You can do it yourself or have your partner do it. (C) 12. Voltmeter select switch - STBY BATT 13 Battery switch - Off after standby attitude indicator off flag disappears Stby indicator is C model only (C) 14. Check STBY BATT ON caution light is illuminated and STANDBY BATTERY voltage is a minimum of 20Vdc (C) STBY ATT IND switch - OFF 16. Fire extinguisher - Check (current, sealed and secured). This is a 2-pound BCP Haylon 1211(bromochlorodifluoromethane) fire extinguisher (n 2-44). Check for: a. Security b. monthly inspection c. pressure in the green d. sealed - cotterkey 17. First aid kit - Check (current, sealed and secured). Located behind the pilot's seat. 18. Seatbelts and harness - Condition and security Inertial locks are located behind each seat and are activated by a 2g-3g decelerating force. You are checking the harnesses and not the locking mechanism itself. Belts should be stowed if not being used. 19. Cockpit - Free of loose gear Check for FOD, General condition of cabin area Passenger compartment - FOD and leaks -- Fluid in the cabin will most likely collect in the "ditch" on the floor directly in front of the rear seats. There is an access panel behind the starboard passenger's seat that leads to the avionics shelf. (you don't have to touch this) Behind the port passenger's seat, there is a black screen. Warm, cabin air is drawn through the screen by the evaporator fan and passes over the evaporator coils where the expanding Freon, absorbing the heat, cools it. The cool air is then passed back to cabin (through the cooling air vents) and the warm, gaseous Freon is passed on to the compressor where the cooling cycle begins. This system is not connected to the forward vents which rely on the forward evaporator for cool air. 20. Right pedal- Full Forward (to expose tail rotor output shaft) 21. Cockpit doors (hinges, jettison handle and mechanism) - Condition and Security. Pilot's door and window - Cleanliness, damage, and proper function of hinges, Ensure the front door is cotterkeyed. Passenger door - Cleanliness, damage, and proper function of hinges. It is not essential that passenger doors be cotterkeyed. The Jettison handles are bright yellow and located near the door high up.

Fuselage (Right Side)

The forward area is constructed of aluminum honeycomb and parts are covered by aluminum or fiberglass as dictated weight to strength ratio and soundproofing the cabin needs.

NOTE: This preflight combines 7.6.3 "Forward Fuselage" and 7.6.7 "Aft Fuselage" because it makes more sense. Your IP may prefer to go by the book. Defer to his or her judgment.

Forward

1. Starboard static port(s) - condition/clear Check baffles are not bent Static air is used for the altimeter, encoding altimeter, airspeed indicator, and vertical speed indicator. In the C model an alternate static vent is located beneath the copilots seat and is selected by pulling the alternate static source knob on the lower left of the instrument panel (n 2-30) 2.Lower antennas - Condition and security The UH10-76 UHF antenna is the large, black blade antenna located below the copilot's seat. The KA-60 transponder antenna is the small, white antenna located below the pilot's seat. 3.Cabin doors (hinges, jettison handle, and mechanism) Condition and Security 4.Cabin - Free of loose gear. see above 5. Landing gear and bumpers - Condition Tow ring - retracted position (forward end of each landing skid) Tube - general condition and clamped, 6 Mormon clamps on skid tube Shoe - The mormon clamps hold on a replaceable steel skid shoe. This part wears out so the skid tube doesn't.       Tube/cross tube connection joint - rivets 3,2,1,0 - any three rivets missing, no two rivets in a row missing, no corner rivets missing, no screws missing. However, it is rare for any rivet to be missing and may be cause for calling it to the attention of your IP or local maintenance tech. Cross tubes - cracking and signs of stressing (bowing) Metal strap assemblies - (Front cross tube connection points) Condition, deterioration, Rubber Bumpers - check for cracking, and no metal to metal contact Cross tube well - (Aft cross tube connection point) no metal bowing or cracking 6. Tiedown Clevis - Security and Safety Wired 7. Ground handling wheels - removed How you got this far without noticing your helicopter had wheels is beyond me, but if you should notice them don't attempt to remove them yourself unless you are away from home field and you have been trained to do so. Otherwise, call a troubleshooter.

AFT

1. Fuel cap - Security Fuel cap should face aft Maximum refueling pressure is 40psi. Ensure that cap lock is in a position such that the wind could not lift it up       The panel above he fuel cap is the location for the fuel pressure transducer and fuel shut-off valve. The fuel pressure transducer is positioned between the boost pumps and the shut-off valve and senses boost pump pressure, it then sends a signal to the fuel pressure gauge. The fuel pressure gauge is protected by a 1/2-amp circuit breaker located on the overhead panel. The fuel shut-off valve is a motor-operated shut-off valve installed in the main fuel supply line. The valve is controlled by an ON/OFF switch located in the instrument panel and is protected by a circuit breaker located on the overhead panel. In the event of an electrical failure, the valve will remain in the last position selected before failure (s 3-8). 2. Drain holes and vent lines - Free of obstructions Vents face forward and drains face aft. The following six drains and vents are (and can be remembered) as follows: TH-57 - Transmission Deck This drain, often attributed to the Hydraulics, is actually the Transmission Deck drain (note the lack of oil streak down the side of the aircraft). The hydraulics drain flows from the reservior to the engine compartment just aft of, and below, the A/F fuel filter. The tranmission deck has two holes in the aft left and right corners, which drain overboard. Flyers - Fuel ram air vent Get - Gang drain Evil - a/c Evaporator Chicks - a/c Compressor (informed by a mx tech that everyone thinks it's the condensor drain but, they're wrong) Often - Oil (the oil drain is the shorter and more inboard drain, the outside one is the condenser) There is an additional drain, the fuel drain, located in the middle of the under fuselage, about where you would expect the fuel bladder to be. The large circular access just aft of the a/c condenser drain and the oil cooler drain goes to the evaporator blower. The hot, pressurized Freon from the compressor is sent to the condenser where the blower cools it as it passes through the condenser coils (visible from the condenser air vent on the port fuselage). The, still pressurized but now cool, Freon is then stored in the receiver dryer until needed. Now, when the a/c is turned on (and becomes functional) a low pressure is created between the compressor and the evaporator, which in turn opens an expansion valve. The expansion valve meters the Freon to the evaporator (s 7-4). 3. RAD ALT antennas (2) - Condition and security The KA-54 radar-altimeter antennas are the two, flat, disc shipped antennas located on the bottom of the helo by the condenser and oil cooler drains. If you did not find them, look again. They look like circular access panels. One antenna transmits continuously while the other receives continuously. 4. Tiedown clevis - Security and Safety Wired Check that it has not swung aft and cracked the lower anti collision light. 5. Lower anti-collision light - condition and security. Water may accumulate in bottom of light casing. 6.VHF antenna - condition and security The DMC70-1A VHF antenna is the spear-type antenna located on the underside of the tailboom. 7. VOR/NAV antenna - Condition and security The DM N4-4 VOR nav is often called the "pull-up bar" antenna don't try it, the darn thing is fragile. 8. Engine oil tank - Check oil level. It may make more sense to check the oil after you close the engine compartment, just don't forget, the sight gauge is not enough, engine oil must be physically checked. That's because there is only one small seal keeping transmission oil separate from engine oil at the freewheeling unit. The only way to tell if that seal has failed is an overfull condition at the Engine Oil tank. If oil doesn't come pouring out, your seal is good. The engine oil system has a capacity of 5.5 qt (11.2 pints); .5 qt in the system and 5.0 qt in the tank (maintenance personnel) and uses AEROSHELL 560. If any other oil is added, flight time is limited to 5hrs due to potential bearing failure because other oils tend to create sludge. Oil from the tank is delivered to the pressure pump that pumps oil through the filter and to various points of lubrication. the system pressure is adjusted to a max of 130 psi by the pressure regulating valve. s 2-15).       On top of the oil tank, at the 12 o'clock position, there is some plumbing and a large, gray box. The smaller tubing is an oil vent line, the larger tubing is the oil cooler and associated bypass plumbing. The gray box is the radiator-type oil cooler. Directly below the cooler is the squirrel cage fan (it is visible from the other side). If return oil is approximately 160 degrees Fahrenheit (71 Celsius) or above, it is routed through the cooler before entering the oil tank (s 2-17).     9. Oil filler cap - Security

Upper Forward Cowling Access Door (Right Side)

(C) 1. rotor brake master cylinder filler cap - secured 2.Hydraulic control servo actuators - leakage and security Forward portions of the compartment - 3 silver tubes, side by side, oriented fore to aft. The center actuator assembly is for collective control and the others are for cyclic control (n 2-24). 3. Control tube actuator assemblies - condition and security Tubes located above the solenoid, not directly connected to the hydraulics. 4. Hydraulic fluid sight gauge - Full (BB at top) This is a round fluid sight window located toward the top of the Hydraulic Power Pack. The Power Pack is the large finned assembly toward the rear of the compartment. Fluid level can be determined by visually inspecting a floating "BB". This will have the appearance of a light reflection on the window and should appear toward the top of the sight gauge. The Power Pack assembly consists of the hydraulic reservoir, pump, pressure regulator and Nr tach-generator mounting pad and is itself mounted to the transmission and driven by the transmission accessory drive shaft. The Power Pack houses the hydraulic fluid reservoir and the system uses 2.25 pints (about 1 pint in the reservoir) of MIL-H-83282 (alt MIL-H-5606) fluid. The filler cap is located on top of the Power Pack and can be inspected from the main rotor hub (n 2-22, n 3-4/6). The Nr tach-generator is driven by the transmission accessory gear shaft and powers the Nr tachometer. The normal operational range of the Nr turbine is 90% - 107%; 107% maximum. If the turbine slows to 90 +/- 3%, the ROTOR LOW RPM caution light is illuminated. Since it is a generator, it creates its own power as long as the gear shaft is turning 5. Hydraulic filter - Leakage and Position of WARNING BUTTON (visible red button indicates a clogged filter). The 15-micron metal filter is located directly to the left of the starboard access panel. Check the warning indicator by feeling the top of the filter. If there is contamination, a red warning button extends upward; otherwise you will feel a dimple where the button is recessed. Check this with your eyeballs; use your fat finger and you'll push in the button and will never know it popped in the first place. Remember that there is no bypass for the hydraulic filter. Hydraulic fluid is fed to the filter by the hydraulic pump (gear-driven, pressure-loaded; located at the base of the power pack) at 600 +/- 25psi. (These numbers double checked with maintenance pubs in Aug 2006, though NATOPS/Systems books have it at 600 +/- 50psi). The Hydraulic low pressure switch is a vertical metal cylinder just forward of filter. The low-pressure switch monitors system pressure. If pressure falls below 300psi, a circuit is closed and the HYDRAULIC PRESSURE light illuminates. The light will self-extinguish if pressure rises above 400psi. Solenoid valve - The solenoid is located in the center of the compartment on the service deck and is easily identified by multiple fluid lines connecting to it. This is a spring-loaded, "fail-safe" valve controlled by a ON/OFF toggle switch located on the pedestal and protected by the HYD BOOST circuit breaker in the overhead panel. Selecting the OFF position on the switch terminates hydraulic boost to the flight controls. It is a "fail-safe" system because it is spring loaded open and will automatically return to the open position in the event of power loss (or a pulled circuit) even if OFF is selected (s 6-4).

Transmission Access Door (Right side)

1. Transmission - condition and leakage The transmission is lubricated by a wet sump system with pressure provided by a self-contained oil pump immersed in the sump. The pump delivers oil through the system at a rate of 4.5-5.0 GPM and an operational range of 30-50psi; 70psi maximum. The transmission oil casing has a capacity of 5 qt. (10 pints) and uses AEROSHELL 555. This system also provides oil to the free wheeling unit via plumbing visible from the port side. The transmission has a gear reduction of 15.22:1 from the output shaft (394 RPM from 6000 RPM)(n 2-12, s ch 4). 2. Pylon support mount - condition and security Large yellow mounting bracket between the air duct and transmission casing. After checking general condition, grip it with your hand such that your thumb is on the washer at the top, sound off "Rocking Rotors" (acknowledged with a "Clear!") and give the A-frame a firm shake. You are checking that: You do not feel a pinching movement under your thumb. See a visible and independent movement of the main rotor shaft from the fuselage (most obvious while looking toward the main rotor). You observe movement of the transmission spike within the surrounding well. There is no popping of a bearing behind the A-pylon washer 3. Transmission oil sight gauge - check for visible oil level (oil level on the first flight of the day is at or below the center bull's eye; an air bubble must be visible on subsequent hops.) 4. Chip detector and magnetic drain plug - security and leakage Located at the bottom of transmission casing at the one o'clock position (should have rubber boots covering them). One of the chip detectors doubles as a drain plug. (s 4-5) Ensure seals are secure and no oil leakage. 5. Transmission spike and well area - condition (sheered rivets, etc) Spike protrudes from the bottom of transmission at the six o'clock position and penetrates the service deck. The spike actually ends right there and is surrounded by the spike well which provides space for the normal movement of the spike. The well is secured to the service deck by rivets; sheared rivets, a warped or loose well plate, or the spike itself being sheared off are indications of excessive transmission movement or a hard landing. It is common for water to collect in the spike-well. 6. Transmission dual focal mount - condition and security (aka: drag link and isolation mount) Square box to the left of the spike-well area. The isolation mount (the box) is constructed of layered "elastomer" and metal which will move under the load of the transmission, then return to its original position when the load is removed. The drag link connects it to the transmission. Inspect the drag link connection and the surface of the isolation mount for unpainted scratches or gauges created by barbell shaft contact indicating excessive transmission movement or a hard landing (s 4-12). 7. The drive shaft is located directly above the isolation mount and goes through the firewall. The KA-Flex drive shaft has flexible couplings at each end and allows for momentary misalignment of the shaft between the engine and the transmission due to transmission movement. The shaft is manufactured by KA-Flex (pronounced K-Flex) and its couplings have the appearance of a leaf-spring construction. 8. Oil cooler air duct - condition and security A thick, coil-hose that blocks the view of everything else. It provides cooling air from the squirrel-cage fan to the transmission oil cooler. In the top left corner of the access door, you will see a connector for the engine wash system. This system cleans the compressor blades only and is not part of the transmission but is integral to the cowling.

Engine Compartment (Right Side)

1. Engine inlet cover - Removed 2. Right side intake duct - Free of FOD/obstructions 3. Engine exhaust stack covers - Removed 4. Exhaust stack - Condition and Security (cracks, dents, burned spots) Look for bluing, signs of overtemp or overstress Ensure there is no contact with the engine cowling. The high temp of exhaust stacks could melt the fiberglass. Check both inside and out 5. Exhaust clamps - Security and safety wired 6. Air frame fuel filter - check Mounted on the forward firewall (right-hand side as you are looking at it). Press the manual test button and verify the caution light in the cockpit. Ensure the drain valve switch is in the horizontal position. There are two different types of A/F fuel filters, each functions identically, but can be identified by the safety wiring. One is safety wired toward the bottom, the other toward the top. The filter assembly consists of a filter bowl, a replaceable filter element, a drain valve, a bypass valve, an impending bypass switch and a manual test button. All of the components are internally located except the manual test button (on top of the filter at the 7 o'clock position) and the drain valve (directly below the filter)(n 2-14). 7. Diffuser scrolls, air transfer tubes and combustion section - cracks and security Aside from the obvious dents and cracks that you are looking for, keep an eye out for bluing on the combustion chamber. This would indicate an overtemp or an internal problem with the combustion chamber (e.g. improper flow of cooling air). Physically check transfer tubes for security (i.e. clamps) if engine not hot. 8. Fire detection element - condition and security The control box is located at the top of the engine compartment at the very front. It is about the size of a battery and lies on its side port-to-starboard. If you are unable to locate it, there is a thin wire that encircles the engine compartment that can lead you to it. The thin wire is filled with argon gas which, when heated, creates a pressure differential. The pressure then trips a switch in the control box that illuminates the ENG FIRE caution light. The fire detection system is protected by the FIRE DET circuit breaker and can be test by a press-to-test button located on the caution panel (n 2-34). This system has a very low false positive incidence; there is a better chance that you're on fire and you have no light than you have a light with no fire. If the light comes on, you are on fire: land immediately. 9. Engine mount - security Place hand on aft end of combustion section and attempt to rock fore and aft. Again, if engine not hot. 10. Right side of engine - condition and leakage (C)11. Rotor brake - condition and security At front of the engine looks like a disk brake. 12. Scavenge oil chip detector - Condition and security Located on the lower, front of the accessory gearbox in the same vicinity as the freewheeling chip monitor. It is the forward most chip detector. 13. Freewheeling unit magnetic drain plug - Leakage and Security The freewheeling unit is mounted to the lower, front portion of the accessory gearbox. The plug is located on its lower starboard side, in the area behind the ECS line. This monitor is not connected to the caution light system (hence the lack of wires) and is only inspected if one of the other detectors illuminate a caution light or during routine servicing (n 2-11). 14.Accessory gearbox chip detector - Leakage and security Located at the accessory gearbox's 6 o'clock position. 15. Twist grip control linkage - condition, security The linkage runs horizontally from the forward firewall to about mid-engine, where it is connected to vertical control rod, which connects to the FCU. 16. Fuel control - Condition and security If you found the throttle linkage, you have found the FCU. 17.Fuel lever stop arm - making Contact with Minimum Speed Stop Ensure FCU fuel lever stop arm makes contact with minimum speed stop and that the corresponding indicator is between 0-5. The fuel lever stop arm is located at the 1 oâclock position as you look at the FCU and the indicator is on the face of the FCU. Both are easily identified if someone moves the twist grip while you are watching. 18.Starter-generator - condition and security Large black cylinder located about mid-engine at the engine's 5 o'clock position. Ensure the (2) Mormon clamps are secure and safety wired. Check for any signs of arcing. This is a 30v, 150amp generator, but regulated to 28v, 105amps. The regulator is on the electronics shelf behind the passenger compartment. 105 is 70% of 150 which is why loadmeter redline is 70% though the gauge itself goes to 100%. When the starter is energized, a circuit is opened between the regulator and the generator, isolating the generator from the electrical system (n 2-20). This information is normally written on a placard on the side of the generator. 19. Generator cooling air duct - condition and security This is air in, not air out. 20. Fuel, oil, ECS lines and electrical connection - condition, security This is on going. Make sure that all hoses and lines are in good condition and that they are properly secured at their connection points.

FYI

1. The Internal oil filter housing Large gray assembly between the diffuser scroll and the exhaust stack. The housing contains the internal oil filter, associated bypass valve and a pressure-regulating valve. As you look at it, the regulating valve is closest and the filter and bypass are directly behind it (i.e. behind being closer to the port side). If you cannot see the safety wiring on top, rub your hand across the top and feel for two distinct wires. 2. Heat shield Square aluminum plate just below the air transfer tube that separates the main engine from other components directly below. Oil or fuel should not be pooled here. 3.Main oil pump Mounted within the accessory gearbox, the pump is run by the Ng turbine, therefore, it provides more oil as Ng and its demand increase. The oil is then sent to the regulating valve, which maintains oil pressure between 50psi minimum and 130psi maximum, with a normal operational range of 90psi to 115psi. This high-pressured oil is needed to balance high axial gear thrust in the torquemeter, which is needed to minimize friction effects and provide an accurate measurement of torque (n 2-5). 4. Compressor bleed air control valve Located to the right of the diffuser scroll. There should be a visible gap (about 1").       The bleed air valve is located on the compressor and bleeds 5th stage air during starting, accelerating and low compressor pressure ratio operations via the control valve which is connected by the required plumbing.     5. Ng tach-generator        Located at 5 o'clock position on the front of the accessory gearbox, just behind the orange oil lines. The Ng tach-generator is driven by the gas power turbine and powers the Ng tachometer. The normal operational range of the Ng turbine is 59% - 105%; 105% maximum (at 100%, Ng rotates at 51,989 rpm). If the turbine slows to 55+/-3%, the ENG OUT caution light is illuminated. Since it is a generator, it creates its own power as long as the Ng turbine is turning     6. A/C compressor        Located near the aft firewall, directly below the tail rotor driveshaft. Though the compressor is connected (through the belt) to the tail rotor driveshaft and therefore constantly turning, it is not functioning unless AIR COND is selected on the environmental control switch panel. Then the compressor relay closes, completing a circuit through the temperature control relay to the compressor. An electrical clutch is then engaged, allowing the routing of compressed Freon gas to the condenser(s 7-4).

Tailboom (Right Side):

The tailboom is a full monocoque structure of aluminum alloy that is lightweight and very strong

1. Tailboom attach point - Condition and security Place finger on seam between aft fuselage and tailboom, rock tailboom and feel for any movement. Behind the panel just forward of seam is the location of the KMT-112 Flux Valve Transmitter for the HSI and RMI)    2. Tail rotor driveshaft cover - security (DZUS fasteners at 45 degrees, last fastener is vertical. A DZUS looks just like a screw head, fasteners shall be 45 degrees (fwd or aft) from vertical except last one, which is vertical (n 7-7). 3. Stabilizer attach point - security of attaching bolts. Check Angle Arm not contacting Stabilizer 4. Horizontal Stabilizer - Condition (dents, cracks, loose rivits) Drain holes. Inspect horizontal stab for cracks, dents, loose or missing rivets; tail boom connections not touching stabilizer; no galvonic corrosion; and (4) condensation drains free of obstructions. Do not mistake drains for the (4) maintenance holes. Note the negative camber (5.5 degrees) to assist with pitch control in forward flight. 5. Right position light -Condition and Security Security of green position light. 6. Main rotor tiedown lanyard - remove At IP's discretion. 7. Vertical fin - condition (dents, cracks and loose rivets). Check the vertical fin bolts (4) - slip marks The vertical fin is a semi-monocoque construction made of aluminum honeycomb and covered with aluminum skin. The fin is offset 5.5 degrees from the longitudinal axis creating a horizontal lift component to assist in countering main rotor torque during forward flight Check for rubber bumper on bottom of fin between the fin and the stinger. 8. Upper anti-collision light - condition and security 9.Tail skid - security The tailskid (aka Stinger) acts as a warning in the event of a tail-low landing and serves to protect the vertical fin in such cases. The skid is rated for 200 lb. downward and 400 lb. upward loads. To ensure the skid is at normal height take a mental note of where on your leg (approx mid shin) the skid bottom normally rests. If there is any deviation it may indicate a hard landing. The cover hole, located at the base of the tailskid, is inspected by looking through the hole. A covered hole is an indication of an excessive tailskid load. Not all of the helos have this hole, some simply have a bolt running through where the hole should be. 10. Tail position light - condition and security 11. Tail rotor gearbox fairing - condition and security.

Tail Rotor Assembly

1.Tail rotor oil level - check oil level 1/8 inch above the line in the sight gauge, oil cap installed. Inspect by looking in the portside grill. Make "ok" sign with fingers and look through thumb/forefinger hole. Verify the cap is in place. The yellow oil cap will be hard to see; look toward the rear and top of compartment. The oil level sight window is just to the left of the chip detector. Verify the chip detector is in place. The tail rotor gearbox provides a 90-degree change in direction of drive shaft as well as 2.35:1 gear reduction (2554 RPM from 6000 RPM). The magnesium gearbox uses 3/8 pint of oil and is splash lubricated. The gearbox uses the same oil as the engine and transmission and should be 1/8" above centerline. The chip detector also serves as a drain plug (n 2-14).    2. Chip detector - Security    3. Crosshead retaining nut - security.        Located furthest from the tail boom in the tail rotor assembly. Look for slip mark and at least one full thread extending through nut     4. Pitch change links - Security.        The links are horizontal and dumbbell shaped. They connect the crosshead and the pitch change horns. They should move freely about their spherical bearings, but there should not be excessive movement. Inspect nuts, disc-shaped washers and spherical bearings for condition and security     5. Pitch change shaft - Condition        Located between the crosshead and the knurled nut. This shaft will not be exposed if the right pedal is not pushed full forward. Inspection is accomplished by scraping your fingernail along the shaft. If you are able to "snag" your fingernail, ground personnel shall be notified immediately. 6. Knurled nut and balancing wheel - Security and Safety wired. The knurled nut is safety wired to the balance wheel, which provides "dynamic balance" to the tail rotor (the wheel, not the wiring). 7. Output shaft hub nut and safety washer - security and safety washer should be bent outboard over two flats of the nut and one flat inboard over the static stop Located in the same area as the rubber bumper. The washer is not easy to see and will require moving the rubber bumper. Inspect for safety wiring and the washer for (2) bends outward and (1) bend inward about the static stop 8. Rubber bumper between yoke and static stop - deterioration Only one is required, but there are usually two present. 9. Inboard end of pitch change links - Condition 10. Trunnion grease fitting - security and safety wired Blue caps located on both sides of the yoke assembly. Inspect for chordwise balance weights and ensure that the nuts are safety wired. The washers below the nuts are actually the balance weights that provide chord-wise balance for the tail rotor. 11. Flapping movement of tail rotor - freedom of movement The trunnion is located inside of the hub (under the blue caps, see Systems pg. 5-9) and cannot be seen, but you are checking for binding in the flapping axis. Blade cannot come within 1" of tail boom and should move easily.       Weights in the trunion or washers on it provide cordwise balancing.     12. Tail rotor pitch change horns - security and safety wiring        The tail rotor pitch change horns are silver and circular, they surrond the blade roots.        Check the tail rotor creep bolts. The creep bolts are located at the root end of each blade. Ensure condition and safety wiring.     13. Tail rotor bolts, nuts and spherical bearings and balancing washers - condition and security        This is the connecting point between the yoke and the blades. The spherical bearings are what the blade actually moves on when it changes pitch. Once you've found them the bolts and nuts should be apparent.        Inspect nuts and bearings for condition and bolt slip mark.        The very thin washers beteween the nuts and the thick washers provide span wise balance for the tail rotor. 14. Tail rotor blades - condition, dents, and cracks The blades are all metal and have a diameter of 5'5". They are constructed of aluminum honeycomb and covered by a stainless steel skin. Stainless steel doublers (the layered effect) have been added at the root end for strength and a stainless steel strip has been added to the leading end to reduce erosion. .    15. Tail rotor blade balance screws - Security.        Each end of the blades have ballast stations for mass balancing and additional weights are added, as required, to balance the blade (i.e. blade weight balance screws at the blade tip) at the time manufacturing. Chord, span and dynamic balance is set at time of assembly     16. Tail rotor output shaft - condition of shaft and leakage around garlock seal        The output shaft is located between yoke and tailboom. Scoring and scraping is acceptable, but excessive damage shall be reported immediately.        The garlock seal is located at base of output shaft, just inside of the gearbox fairing. It forms the seal between the output shaft and the gearbox.

Tailboom (Left Side)

Check/inspect port side of tail boom for same criteria as starboard side after completing tail rotor check Aft Fuselage (left side)

1. Engine oil tank sight gauge - level Visible through screen just forward of the access panel. Ensure that oil is above the half way mark. 2. Scavenge oil filter impending bypass indicator - not extended. This filter has a 10-micron rating. Scavenge oil comes in from behind the filter, is filtered, then sent to the oil cooler through the line visible front access panel. 3. Driveshaft safety pin - freedom of movement This pin looks like a small knurled nut and is located just aft of the Thomas coupling on the driveshaft. It should be loose and free to twist. If not, it is an indication that the tail rotor driveshaft has be overstressed. 4. VOR/NAV antenna - condition and security. 5. Baggage compartment - Gear adrift, condition leaks (C)6. Standby battery circuit breaker - In. 7. Bagage compartment door - Security.

FYI

1. That disk in the tail rotor drive is a Thomas Coupling -Looks like a bunch of washers bolted together. Ensure there is no excessive gaping between the discs. 2. The Oil Drain Valve is just to the left of the filter and below the oil tank. It should be in the horizontal/closed position 3. Located at the front of the access area is the Squirrel Cage. The fan is driven by the tail rotor driveshaft and provides cooling air to the oil, transmission and hydraulic systems.

Engine Compartment (Left Side)

1. Engine inlet cover - Removed 2. Left side intake duct - free of Obstruction /FOD 3. Engine exhaust stack cover - removed 4. Exhaust stack - Condition and security (cracks, dents, burned spots) Ensure there is no contact with the engine cowling. 5. Exhaust clamps - security and safety wired. 6. Fire detector element - condition and security. 7. Anti-ice actuator arm - forward (off position) There is a small motor just aft of the lever, which takes about 10-15 seconds to open/close the valve. If it is fwd, go to cockpit, turn on battery and cycle anti-ice switch on (15 sec) then off (15 sec), then recheck lever. 8. Diffuser vent stand pipe - oil leakage and security A 2"-3" protrusion just to the left of center on the diffuser scroll. This vents air in the event of an overpressure in the diffuser. Oil leakage will be an indicator that this has happened. 9. Scroll, air transfer tube, combustion area - cracks and security 10. Igniter - condition and security The igniter plug is on the port side of aft of the combustion section and a silver connection goes directly from it to the exciter box. The igniter only operates when the starter is energized and the generator is isolated. 11. Combustor drain - security and leakage Located at the lowest part of the combustion chamber. The plug directly aft of the drain valve is an alternate location for the valve when this engine is used in different aircraft (maintenance personnel). Combustor drain is held shut by air pressure, when Ng hits zero this drain opens. 12. Fuel line and nozzle - Condition and leakage Located on the very back of the combustion chamber. The fuel manifold plug is on the starboard side and has an orange fuel line running to it. 13. Thomas couplings, tail rotor driveshaft - Condition and security 14. ECS compressor/drive belt - condition and security. 15. Heat shield drain - Fuel or Oil Leakage If you are having trouble finding this drain look for the silver drain tube just forward of the small silver box under the heat sheild. That box is the Turbine 6th, 7th, and 8th oil sump tank. 16. Accumulators - Cracks and security Two identical cylinders connected at a 90-degree angle, just above the governor. These dampen transient surges of air pressure. 17. Nf governor - condition and security Located behind the accessory gearbox at the 9 o'clock position, just above the tail rotor driveshaft. Varies the air pressure signals to the fuel control unit in order to prevent lag time between Ng and Nf. The system has no effect unless the twist grip is in the full open position. (s 2-21) (C) 18. Standby generator - condition and security. On the B model there is plate fastened to the aft of the accessory gear box by four bolts covering the point where the starter generator would be mounted. 19. Engine fuel pump, filter and drain - condition and security. Mounted below the forward end of the tail rotor driveshaft. The pump is a gear-driven, pressure fed pump that delivers fuel at 650-750psi. 20. Start counter - condition and security. On many aircraft this has been removed. You will see two holes on the port side of the Accessory gearbox where it used to be bolted on. If it is present it is small (~1.5"x5"), mostly hidden, located under the side of the accessory gearbox. Numbers can be read from the back of the counter. This counter is for maintenance and does not effect the helo. 21. Fuel, oil, ECS lines, and electrical connections - condition and security. 22. Engine mounts - security 23. Linear actuator and mount - security The whole system is for "droop compensating" (s 2-22). The linear actuator is for fine adjustments "beep control/inker-dinker" and the throttle linkage is for collective pitch change adjustments. 24. Main driveshaft coupling - condition, security, and grease leakage. Check temp-plates (four places) for evidence of elevated temperature indicated by dot changing color to black. CAUTION: If any temp-plate is missing or has black dots, consult maintenance personnel. These dots are not present on the new KA-Flex drive shaft.

FYI

1. Located on top of the turbine section on the right are four bayonet-type thermocouples that sense the temperature between the Ng and Nf turbines. The readings are averaged and then relayed to the TOT gauge in the cockpit. This portion of the system does not give any indications to the pilot, rather the diamond J, TOT gauge displays the temp and signals the TOT caution light if 927 degrees Celsius is exceeded or a time/temp situation occurs for the time limited ranges (s 2-8) 2. The plumbing on the left of the thermocouples is engine oil for turbine lubrication and cooling. 3. Drain plug - on the lower aft of the engine is another drain for aircraft where this engine is mounted at an angle. This plug should be safety wired. 4.The Pc air filter - Filters air before it is passed on to the Nf governor. Reverse installation is possible with the filter; nut facing aft is the correct way. It is located near the diffuser, which it is connected to by a silver tube 5. Nf tach-generator - A Black cylinder, located behind the linear actuator. Driven by the free power turbine and powers the Nf tachometer. The normal operational range of the Nf turbine is 97% - 100%; 100% maximum (at 100%, Nf rotates at 33,956 rpm). Since it is a generator, it creates its own power as long as the Nf turbine is turning 7. Exciter box - Located on the front of the accessory gearbox at the 7 o'clock position, the exciter box is an electrical capacitor which changes the aircraft's small nominal DC current to a large pulsating DC current. (The same as in the T-34)

Transmission Access Door (Left Side)

1. Transmission oil cooler - leakage and Free of Obstruction Located on top of the transmission at the 6 o'clock position. The oil cooler receives its oil directly from the filter and its air from the squirrel cage, cooling fan. It has a thermal bypass, which closes when oil temperatures rises, forcing the oil to be cooled by the radiator-type cooler. The regulated air then is passed to either transmission jets or the freewheeling unit. 2. Transmission oil filter - Leakage The large visible portion is the filter housing, inside of the housing is the filter. Mounted to the front is the oil filter head, which houses: The oil monitor - hexagonal nut mounted at an angle. This is a magnetic chip monitor, but is not wired to caution light system. It is only checked during routine servicing or if the pilots are alerted through the caution light. Drain valve - drains oil from the filter for maintenance purposes. Temp bulb - transmits oil temp to gauge in cockpit. Normal operating range is 15 - 110 degrees Celsius; 110 degrees maximum. Located on the forward end of the transmission oil filter. It is the outboard most of the two electrical components. By feel it has two wires coming out of it. Filter bypass valve - in case of a clogged filter High temperature switch - exceeding 110 degrees will close the switch, which illuminates the TRANS OIL TEMP caution light (s 4-4). This is located right next to the Temp Bulb, on the inboard side. It's hard to see but by feel it only has one wire coming out of it. 3. Left side of transmission - Condition and leakage The T-fitting sends oil forward for a direct, wet-line reading of transmission oil pressure. There is a low pressure switch connected to this line that illuminates the TRANS OIL PRESS caution light if it senses a pressure of 30 +/- 2psi. The other line enters the freewheeling unit at the back of the accessory gearbox and the oil is returned in the line directly above the T-fitting (s 4-5). The thin cylinder sticking out about halfway up the transmission casing at the 7 o'clock position is the system's pressure regulating valve. It is a spring-type valve that bleeds off internal pressure by allowing oil directly back into the sump, bypassing the jets (n 2-12). 4. Pylon support mount - Condition and security. Same as starboard. 5. Main driveshaft coupling - condition, security and grease leakage. Check Temp-Plates (four places) for evidence of elevated temperature indicated by dot changing color to black. CAUTION if any temp late is mission or has black dots, consult maintenance personnel. These dots are not present on the new KA-Flex drive shaft.

Upper Fuselage Area

Caution: Walking on aircraft roof may damage the airframe. Stand only on aft 12 inches of black nonskid area. You must wear your helmet (chin strap fastened) to climb on top of the aircraft. For practice preflights sign a helmet out of the paraloft.

1. Engine oil cooler radiator - free of obstructions Located at the rear in the aft fairing. 2. Exhaust stacks - Cracks, dents, burned spots. 3. Upper fairing and cowling - condition and security The forward fairing is constructed of aluminum honeycomb with a fiberglass skin. The aft faring is constructed of aluminum honeycomb with a fiberglass skin. The engine fairing is made of a heavy aluminum alloy. The induction fairing is constructed of fiberglass for weight saving and to channel air to the engine. (C)4. GPS antenna - condition and security. 5. Transmission compartment - FOD, security 6. Cooling air ducts and fittings - security There is an orange and black tube that is used by the transmission oil cooler. 7. Hydraulic filler cap - security This is the top of the Power Pack located at the transmission's 11 o'clock position ensure safety pin properly installed. 8. Transmission oil filler cap - security Located on to of the transmission at the 1 o'clock position. Ensure security by physically twisting the cap. 9.Control rod ends - security Visually inspect the Actuator Control Tubes and their connections to the Main Rotor controls. Up arrows, bolt heads in direction of travel of the hub, lower ends torque striped, upper end safety wired.

Rotor System:

1. Swashplate and lower end of pitch change control rods - security The swashplate and support assembly consists of rotating and stationary swashplates, pivot sleeve, swashplate support and drive link. The drive link is connected to the connected to the mast (via a lever and a spline mounted collar set) at the top and to the rotating swashplate at the bottom. The rotating swashplate is connected to the stationary swashplate by a set of bearings and bearing cap. The stationary swashplate is connected to the top of the pivot sleeve, which is of a uniball construction. The pivot sleeve is mounted to the swashplate support, which in turn is mounted to the transmission (s 5-12). Cyclic controls tilt the stationary swashplate about the uniball, subsequently tilting the rotating swashplate. This tilting will cause the blades to change their plane of rotation. Collective controls lower the front of the collective lever, causing the back to rise, which lifts the whole pivot sleeve. This lifting will cause the pitch angle to increase and vice versa. Have plane captain raise and lower collective to ensure freedom of movement within the whole system. Verify the word "TOP" is in fact on the top of the collective lever. 2.Collective boot - security and safety wired bottom, safety clamped top This is the black, rubber boot at the base of the mast. 3. Drivelink, lever collar set - security. These will cause the rotating swashplate to rotate at the same speed as the rotor system. The drive link is vertical and the lever is horizontal. 4. Mast - condition (nicks, cracks, etc) 5. Static stops - condition and security These two stops are mounted to the bottom of the rotor hub. 6. Inside of hub assembly -condition and security check end of torsion straps. Potting compound should be all that is visible on the butt end of tension torsion straps. 7.Control rods to the pitch horns - Security Ensure proper installation of the pitch change rods by verifying the course threads are on the bottom and fine threads on top. 8. Flap restraint assembly - condition and security Designed to prevent excessive flapping at low rotor RPM. At low RPMs (32-25% Nr), the springs will pull the restraint arms (flyweight design). 9. Mast nut and locking device - Security 10. Pillow block and blade grip reservoirs condition and excessive grease around seals. These are the rounded caps toward the top of the yoke. They have grease gun fittings on top to allow for lubrication of the inner assemblies (e.g. flap bearings). The blade grip resevoirs are checked by inspecting the brass nut on the top of the blade grip. This is where overflow grease comes out. Also there is a rubber seal between the blade grips and the pitch change horns. This should be inspected for ware and leakage. During the summer you may see fluid resembling hydraulic fluid. This is just the grease getting broke down by the heat. There is no need for concern unless it is excessive. The yoke is mounted to the mast by a splined trunnion that is held in place by pillow blocks. The pillow blocks have bearings inside, allowing the blades to flap about the trunnion. The yoke has 2.25 degrees of preconing to relieve bending stress on the yoke, blade grips and the root ends of the rotor blades. 11. Blade grip assembly - Security They have grease gun fittings on the side to allow for lubrication of the inner assemblies (e.g. pitch change bearings). Check for (3) retaining bolts. 12. Blade latch nut - (a.k.a. horizontal latch bolt) 13. Blade retention bolt and nut - condition and security; plastic cap on top of bolt. (a.k.a. vertical through bolt) 14. Main rotor blades - condition; position blades at 90/270 Position. Turn blades in a clockwise rotation from the hub.

CAUTION: When rotating main blades from the hub, if blades will not turn or resistance is felt, discontinue. Do not force the rotation and proceed with applicable maintenance directives. Forcing the rotation may damage the Nf turbine.

This is an indication of carbon lock. Carbon lock is a buildup of carbon (soot from combustion) in the turbine section. The carbon causes the turbine rotors to jam. Do not rotate from blade tip - you might not be able to feel the binding.

FYI

The blades are of a nonsymmetrical droop design composed of an extended aluminum alloy nose block and stainless steel skin over honeycomb filler. The main rotor blades have a diameter of 33'4" with a 13" chord and weigh approximately 94 pounds each. Like the tail rotor, stainless steel doublers (the layered effect) have been added at the root end for strength. There are three items added to each blade:

Drag plates - Located at root on the trailing edge. These are mounted on the blades at the time manufacturing and are balance Steel bonding doublers - The layering at the root of the blade Trim tabs - One in the middle and one toward the tip

Upper Forward Cowling Access Door (Left Side):

1. Hydraulic control servo actuators - Leakage and Security

Same as starboard side

2. Control tube actuator assemblies - Condition and Security

Same as starboard side Forward Fuselage (Left Side):

1. Cabin Doors, Hinges, jettison handle, and mechanism - Condition and Security 2. Landing gear - condition

Same as starboard

3. Tiedown Clevis - Security and Safety Wired. 4. Ground Handling Wheels - Removed

Should be removed by maintenance

5. Cargo hook and release cable - condition, security

Stowed Position is 45 degrees aft. The cargo hook cannot be mounted on older Bravo models. Total structural weight capability is 1500 lbs but aircraft gross takeoff weight may limit max weight you can lift. It has three releases: one electrical (Cargo Release Switch - upper button on cyclic) and two manual (release at the hook for ground handler; emergency release in cockpit)

6. Vertical landing light - security 7. Antennas (Transponder, UHF) - condition and Security 8. Cockpit door jettison handle and mechanism - Condition and Security 9. Left Static port - Condition/Clear 10. Fuselage underside - Condition and Leakage