1C-5M-2-1_401-500.pdf

• Ground all equipment used during this defueling procedure. Failure to comply could result in injury to person-nel.

• Ensure that the hose is securely tted to the jettison mast. Failure to comply could result in injury to personnel or damage to equipment.

c. Connect a 3-1/2-inch inside-diameter, rubber impregnated canvas hose that will withstand 15 PSI from the beaded end of the fuel jettison mast being used to the external defueling unit or fuel truck. The hose must be secured to the jettison mast with a clamp and to the external defueling unit with appropriate connector or coupling to prevent the hose from coming loose during defueling operations. To support the defueling hose, position a maintenance stand aft of the fuel jettison mast and secure the hose to the stand with a clamp.

Carefully monitor the receiver unit during defueling to prevent fuel over ow. Failure to comply could result in injury to personnel or damage to equipment.

d. Depressurize fuel tanks in accordance with instructions in TO 1C-5M-2-5, Chapter 2.

Control of individual tank defueling is provided by removing both boost pump elements from the tank until the tank is to be defueled and by removing the fuel control valves from all tanks (including main tanks) to prevent uncontrolled gravity ow of fuel into tanks. Failure to comply could result in injury to personnel or damage to equipment.

e. Open the fuel level control valve circuit breakers and tag with a warning tag. (See Figure 1-18.) Remove the fuel level control valve from all tanks (including main tanks) to prevent gravity ow of fuel into the tanks. (Refer to TO 1C-5M-2-5, Chapter 5.) Do not close the circuit breakers until tank has been closed and fuel level control valve has been installed.

f. Remove fuel boost pump elements from all extended range and auxiliary tanks that contain fuel. (Refer to TO 1C-5M-2-5, Chapter 7.)

g. Gain access and place the following valves in positions indicated by using the manual override lever:

VALVE POSITION

Center Separation Closed Left Separation Open Right Separation Open Aerial Refuel (Both) OFF No. 1 Isolation Closed No. 2 Isolation Closed No. 3 Isolation Closed No. 4 Isolation Closed Left Jettison Closed Right Jettison Closed Ground Refuel OFF Crossfeed Valves L and R Closed

TO 1C-5M-2-1

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h. Position personnel at left and right jettison masts. Secure the hose to the maintenance stand in such a manner as to provide sufficient length to reach the jettison mast. The weight of the hose is to be supported by the stand. Failure to comply could cause damage to the jettison mast.

i. Ensure that the aps are down or that the hinged access panels, 3233-3 (LH) or 4233-3 (RH), are open.

j. Attach hose to jettison masts, securing it with a clamp.

k. Secure the other end of the hose to an approved type of fuel container. (Refer to TO 1-1-3.)

Defuel tanks in the sequence noted:

No. 2 and No. 3 extended range No. 1 and No. 4 extended range No. 2 and No. 3 auxiliary No. 1 and No. 4 auxiliary Failure to comply could cause structural damage to the airplane.

l. Defuel the No. 2 and No. 3 extended range tanks as follows:

(1) Install both fuel boost pump elements. Refer to TO 1C-5M-2-5, Chapter 7.

Verify hose security to fuel container and mast. Failure to do so could result in injury to personnel, loss of life, and/or extensive damage to equipment.

(2) Manually place the left and right jettison valves in the open position. Ensure that drain hose is securely connected to fuel container and to mast.

RESULT: Fuel should ow from both masts.

(3) After fuel has stopped draining, manually close the jettison valves.

NOTE

After the above procedure is accomplished, signi cant amount of fuel will remain in the tanks.

(4) Pull both fuel boost pump elements down to the rst stop in accordance with instructions in TO 1C-5M-2-5, Chapter 7.

(5) Drain fuel boost pump cavity by removing the drain plug.

(6) Insert a hose adapter into the drain port. Attach a hose to the adapter and secure the other end to an approved fuel container. Ground container to airplane and approved earth ground. (Refer to TO 1-1-3.)

(7) Reinsert both fuel boost pump elements into housing.

RESULT: Fuel should drain into container.

(8) After fuel stops draining, remove hose and adapter. Reinstall the drain plugs.

(9) A small amount of fuel will remain in the tanks. This fuel can be removed by draining through the condensate drain valves in accordance with instructions in this chapter.

m. Defuel No. 1 and No. 4 extended range tanks by repeating procedures in Step l.

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n. Defuel No. 2 and No. 3 auxiliary tanks by repeating procedures in Step l.

o. Defuel No. 1 and No. 4 auxiliary tanks by repeating procedures in Step l.

3.2.13 Ground Transfer of Fuel from Tank to Tank. Refer to TO 1C-5M-2-5, Chapter 5, for procedures to transfer fuel from tank to tank.

3.2.14 Draining Condensate from Fuel Tanks. (See Figure 3-8.) Drain valves in the lower surfaces of the wings permit water condensate to be drained from the fuel tanks as follows:

All electrical power must be removed from airplane prior to draining fuel and all equipment in use must be grounded. Failure to comply could result in injury to personnel and damage to airplane or equipment.

a. Depressurize the fuel tanks in accordance with TO 1C-5M-2-5, Chapter 2.

b. Place the top of the condensate drain tube (PN 61D25082 or equivalent) in the center of the condensate drain valve.

(See Figure 3-8.)

c. Push upward on the condensate drain tube until the poppet opens and allows condensate to drain into jar.

d. Remove the top of the condensate drain tube from poppet seat when all condensate has drained into the jar.

e. Repressurize the fuel tanks in accordance with TO 1C-5M-2-5, Chapter 2.

3.3 CONCURRENT SERVICING.

The following paragraphs provide, in abbreviated form, procedures for concurrent servicing of C-5 airplanes. Concurrent servicing operations are not required on MAF (Mobility Air Forces)/Commercial carrier aircraft unless refueling defueling with JP-4, loading/downloading munitions or explosives, or servicing LOX while performing maintenance. Simultaneous srevicing of fuel while loading passengers, cargo, performing maintenance, aircrew members performing inspections, or operating aircraft system is considered to be a normal fuel servicing operation. Concurrent servicing is de ned as the simultaneous servicing of JP-4, loading/downloading munitions or explosives, or servicing LOX while performing mainte-nance. The requiremens of the following procedures must be adhered to when the concurrent servicing of C-5 airplanes is accomplished. It is the responsibility of all involved supervisors to ensure that personnel participating in the operation are thoroughly trained when using these procedures.

3.3.1 Concurrent Servicing Terms and Abbreviations. The following terms and abbreviations are used during concur-rent servicing:

CSS Chief Servicing Supervisor SPRM Single Point Refueling Monitor REO Refueling Equipment Operator RPO Refuel Panel Operator CFR Crash Fire Rescue

3.3.2 Location of Personnel During Concurrent Servicing. The concurrent servicing personnel shall be stationed at the following locations:

CSS Stationed at the nose of the airplane. Moves as required.

SPRM Stationed at the SPR. (Note: One required at each SPR being serviced.)

REO Stationed at refueling equipment unit.

RPO Stationed at ight engineer panel.

Transportation Personnel Stationed at passenger and baggage/cargo areas as required.

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Loadmaster or Passenger Representative Positioned in the passenger compartment when passengers are onboard.

3.3.3 Fuel Servicing Safety Zone. The servicing safety zone is the area within 25 feet of the airplane fuel vents and 50 feet from any pressurized fuel servicing component.

3.3.4 Refueling Team. The refueling team will consist of the following personnel:

a. One CSS, one person to monitor each SPR being serviced, one person to operate the refuel panel, one fuel specialist (2F0X1) for each fuel servicing unit used, and a passenger compartment monitor (loadmaster or passenger represen-tative) if passengers remain onboard during refueling. These are minimum requirements. Additional personnel are optional.

b. The CSS shall have full and nal authority over all participating personnel and phases of the concurrent servicing operation with the exception of the deployment and control of CFR vehicle and personnel.

c. The CSS will wear a re ective vest with the letters CSS on the front and back. Letters will be at least 6 inches high and 4 inches wide, and made of re ective material. Re ective material used must be at least 1 inch wide.

3.3.5 CSS Duties Prior to Airplane Arrival. The CSS must determine, de ne, or ensure the following prior to airplane arrival:

a. Speci c servicing requirements to include grounding/bonding sequence for the speci c airplane.

b. Timing of any servicing and maintenance required, cargo/baggage loading/unloading, eet servicing, catering/food service functions, and any other function that requires personnel or equipment movement into or within the fuel servicing area.

The 40K loader open- ame heater will not be used in servicing area. Failure to comply could result in injury to personnel or damage to airplane.

c. Verify that vehicles involved in the concurrent servicing operation are equipped with a spark arresting device. Vehicles not meeting these requirements will not be allowed in the concurrent servicing area as long as refueling is in progress.

d. Ensure that required interphone headsets are available. At least four intercom headsets are required for C-5, two with 100 foot cords and two with 50 foot cords.

e. Prior to airplane arrival, ensure refueling equipment is checked for serviceability under pressure.

f. Ensure all personnel involved in concurrent operations, such as maintenance teams, aerial port, passenger service, etc., are aware of the total requirements of the servicing prior to airplane arrival. Individual requirements are:

(1) Report to the CSS any condition that might jeopardize safety.

(2) Coordinate all phases of their operation with the CSS.

(3) When concurrent servicing operations are in progress, all personnel, unless previously cleared, shall report to and receive the CSS’s concurrence prior to entering the concurrent servicing area.

g. The CSS will ensure communications to the re department through Job Control or the Command Post are operational and immediately available. Ensure the re department is noti ed at least 15 minutes before starting concurrent servic-ing operations to allow airplane rescue and re ghting vehicle positioning for a 3-minute response time. When passengers/patients are on board, the number of passengers/patients will be given to the re department.

h. Ensure that concurrent servicing team members are aware of emergency procedures. In the event of an emergency:

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(1) Stop fuel ow.

(2) Determine if evacuation of passengers from airplane is required.

(3) Initiate normal or emergency evacuation of airplane as necessary.

(4) If situation/hazard warrants, bring in CFR and turn operation over to Crash Fire Rescue personnel.

(5) Assist CFR personnel as required.

3.3.6 CSS Duties upon Airplane Arrival. The CSS will ensure that the following is accomplished upon airplane arrival:

a. Ensure correct airplane parking, grounding, and chocking.

Operating external power units will be parked at least 50 feet from pressurized fuel carrying servicing components and at least 25 feet from aircraft fuel cents during fuel servicing operations. They will be placed outside the fuel servicing safety zone and when possible positioned upwind from the servicing operation.Failure to comply could result in injury to personnel or damage to airplane.

b. Direct positioning and connecting of external units. Remain in constant intercom contact with personnel in cockpit and at the airplane refueling control panel during and until refueling is terminated. When passengers are onboard, remain in constant intercom contact with passenger compartment supervisor.

c. Determine the status of the airplane and its systems, and call for maintenance specialists as required.

d. Ensure that cabin crew personnel have briefed passengers concerning fuel servicing precautions, including emergency egress procedures, if they are to remain onboard.

e. Verify ight crew member or passenger representative remains in attendance within the airplane when passengers are onboard.

f. Verify that a major CFR (P-2/4/15/19/23) is standing by in immediate area when passengers are to remain onboard during refueling with JP-4 or Jet B fuel.

g. Remain near nose of the airplane to observe all operations and remain on interphone during the entire refueling phase of the operation.

h. Clear support equipment to be positioned at airplane.

i. Position lavatory servicing truck and potable water truck as required.

j. Position and ground hydrant hose cart(s) or refueling vehicles as required.

Maintenance stands and equipment used in concurrent servicing must be positioned to ensure that the airplane is not damaged when it settles during refueling operations.

k. Positioning maintenance stands and bonding to airplane. Rubber wheeled maintenance stands need not be grounded, but will be bonded, and may be unbonded while being repositioned during concurrent servicing. Maintenance stands should not be closer than 1 foot from the underside of fuselage, nacelles, or wings.

l. Ensure that ramps and stairs are in their proper position and unobstructed to enable emergency egress.

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Voice contact must be established and maintained at all times during the fuel servicing portion of concurrent servicing operations when passengers are on board the airplane. The airplane intercom system should be used as the primary means of maintaining voice contact between the fuel servicing team members. If the airplane intercom system is inoperative and cannot be used to maintain voice communications, portable hand-held radios may be used to provide voice contact subject to the following stipulations. Radios can be used within the fuel servicing safety zone, however, only intrinsically safe radios can be used within 10 feet of any airplane fuel vent outlet, fuel spill, or fuel tank truck being lled from airplane defueling. Failure to comply could result in injury to personnel or damage to airplane.

m. Position a serviceable re extinguisher in the immediate vicinity of each of the airplane SPR being serviced and another at the ground power unit and/or at each operating APU which does not have an operable internal re suppres-sion system.

Team members will not break interphone contact unless directed by or coordinated with the CSS. At no time will the interphone system be disconnected during refueling operations. The refuel panel operator and SPR operator shall maintain constant voice contact with the CSS during concurrent fuel servicing. The airplane interphone system will be used for this purpose. Failure to comply could result in damage to airplane.

n. Direct all refueling team members to take their positions and establish interphone contact.

3.3.7 Concurrent Servicing Procedures.

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• Servicing of gaseous or liquid oxygen simultaneously with petroleum servicing is not authorized. Failure to comply could result in injury to personnel or damage to airplane.

• A clear exit path shall be maintained to permit rapid evacuation of refueling vehicles, personnel, and other equipment in the event of an emergency. Failure to comply could result in injury to personnel.

• Ensure driver(s) stay in vicinity of their vehicle(s). Vehicles will only be started and moved upon command of the CSS. Failure to comply could result in injury to personnel or damage to airplane.

• Personnel entering fuel servicing safety zone will dissipate static electricity by grasping an approved ground point. Refueling personnel will periodically ground themselves as they move about performing their duties.

Failure to comply could result in injury to personnel or damage to airplane.

All servicing vehicles will be chocked during servicing operations. Failure to comply could result in damage to equipment or airplane.

NOTE

• The following additional precautions and procedures shall be strictly adhered to when passengers are permitted to remain onboard or are loaded/unloaded during concurrent operations.

• Concurrent servicing operations are not required on MAF/Commercial carrier aircraft unless refueling/defuel-ing with JP-4, loading/ downloading munitions or explosive, or servicing LOX while performing maintenance.

Simultaneous servicing of fuel while loading passengers, cargo, performing maintenance, aircrew members performing inspections, or operating aircraft system is considered to be a normal fuel servicing operation.

a. All passengers will be briefed on the hazards of fuel servicing and, conditions permitting, be given the option to deplane prior to beginning the operation. Passengers remaining onboard will remain seated during concurrent opera-tions unless otherwise directed. No smoking will be allowed.

b. Personnel participating in cargo operations and maintenance on the airplane may remain in the area and are not considered passengers.

c. Exits shall be unlocked and opened insofar as practical. Necessary ramps/stairs shall be positioned and unobstructed so that passengers can be expeditiously evacuated. An external staircase should be provided for upper deck passengers whenever the internal stairs are stowed due to cargo loading operations being conducted concurrently with fuel servicing.

d. During concurrent fuel servicing, the deadman control valve associated with the K-500 or K-9 refueler and hydrant hose trucks will be operated/held by the SPRM, the CSS, or the REO.

e. Maintenance Limitations. The following types of maintenance are authorized:

(1) Interior power-on electrical maintenance to include LRU exchange and checkout. (Transmitting on the high frequency (HF) and SATCOM radios, radar, radar altimeter, TACAN, or IFF equipment is prohibited.) Inertial Navigation System (INS) and Fuel Saving Advisory (FSAS) may remain energized. Satellite Communications (SATCOM) radios may be operated in the transmit mode if the antenna beam is pointed at least ten degrees above the horizon.

(2) Exterior power-on electrical maintenance of airplane installed equipment outside the fuel servicing safety zone.

(3) Maintenance and servicing of unpressurized hydraulic systems.

f. Maintenance Prohibitions. The following types of maintenance are prohibited:

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(1) Maintenance on airplane or engine fuel systems which requires the opening of fuel lines, fuel tanks, or replace-ment of plug-in components (fuel probes).

(2) Maintenance in wheel wells when refueling equipment is pressurized, however, liquid nitrogen servicing and single wheel replacement are permitted.

(3) Maintenance requiring the use of jacks shall not be performed with the exception of single wheel changes on multi wheel main landing gear or dual nose wheel landing gear provided the jacking is performed at the affected gear.

(4) No ammable uid carrying lines will be broken unless equipped with quick disconnects.

g. Cargo Loading Limitations. The following cargo loading limitations apply:

(1) Powered vehicles may be driven on and off the airplane during fuel servicing; those without spark arrestors, however, will not be driven into the fuel servicing safety zone until the fuel servicing equipment is depressurized.

After these vehicles are completely inside the cargo compartment or outside the safety zone, fuel servicing may be resumed.

(2) Winching rolling stock and non-sparking palletized cargo is permitted during fuel servicing.

(3) A loadmaster or passenger representative will not leave the cabin while passengers are onboard.

(4) Passengers will not be allowed in cargo compartment while winching of rolling stock or pallets is being accom-plished.

3.4 HYDRAULIC SYSTEMS SERVICING.

3.4.1 Hydraulic Servicing Provisions.

Do not service any hydraulic reservoirs while maintenance is being performed on the associated hydraulic system.

Failure to comply could result in injury to personnel.

(See Figure 3-9 and Figure 3-10.) Two methods are available for hydraulic reservoir servicing. A ground ll connection in the right MLG fairing is provided for external servicing. A hand pump and uid receptacle are provided in service center No.

3 for in ight or ground servicing. A selector valve in service center No. 3 is used for servicing each of the four hydraulic systems on the airplane. An unpressurized cylindrical reservoir with a sight gage attached is contained in each of the hydraulic systems. For hydraulic reservoir draining see TO 1C-5M-2-3, Chapter 2.

3.4.2 Internal Hydraulic System Servicing.

a. Prepare hydraulic system before servicing reservoir. (Refer to No 1, 2, 3, or 4 Hydraulic System Servicing, Step a.)

b. Reduce system pressure to zero PSIG.

c. Locate the reservoir ll receptacle at service center No. 3 and provide source of hydraulic uid; use Speci cation

MIL-PRF-83282.

d. Position the selector valve handle to ll the desired system reservoir.

e. Depress and hold the selector valve handle.

f. Operate the reservoir ll hand pump.

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g. Monitor the sight gage on the selected system reservoir; advise when to release the selector valve as the hydraulic uid reaches the FULL 0 PSIG mark on the sight gage.

h. Remove the emptied uid containers and clean up any spillage.

3.4.3 No. 1 Hydraulic System Servicing. (See Figure 3-9 and Figure 3-10.) Service the system in accordance with the following procedures. The reservoir uid capacity is as follows:

SYSTEM RESERVOIR CAPACITY -

US GAL

REFILL CAPACITY - US GAL

AF68-0213, AF68-0216, and AF69-

10.01 2.70

AF83-1285 and up 9.4 2.7

a. Ensure that the following items are accomplished before servicing the No. 1 hydraulic system:

(1) Flight controls faired.

(2) Cargo doors closed in accordance with TO 1C-5M-2-12, Chapter 2 and TO 1C-5M-2-12, Chapter 3.

b. Reduce system pressure to zero PSI.

c. Open the ground ll connection access door.

d. Connect a hand-operated hydraulic service cart to the ground ll connector.

e. Position the selector valve handle in service center No. 3 to ll the No. 1 system reservoir.

f. Depress and hold the selector valve handle while pumping Speci cation MIL-PRF-83282 hydraulic uid into the system.

g. Monitor the sight gage on the No. 1 system reservoir.

h. Release the selector valve handle when the hydraulic uid reaches the FULL 0 PSIG mark on the sight gage.

i. Disconnect the service cart and replace the cap on the ground ll connector.

j. Close the ground ll connection access door.

3.4.4 No. 2 Hydraulic System Servicing. (See Figure 3-9 and Figure 3-10.) Service the system in accordance with the following procedures. The reservoir uid capacity is as follows:

SYSTEM RESERVOIR CAPACITY - US

GAL

REFILL CAPACITY - US GAL

AF68-0213, AF68-0216, and

AF69-0024

5.70 1.54

AF83-1285 and up 6.30 1.40

a. Ensure that the following items are accomplished before servicing the No. 2 hydraulic system:

(1) Flight controls faired.

(2) RAT retracted.

b. Reduce system pressure to zero PSIG.

c. Open the ground ll connection access door.

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d. Connect a hand-operated hydraulic service cart to the ground ll connection.

e. Position the selector valve handle in service center No. 3 to ll the No. 2 system reservoir.

f. Depress and hold the selector valve handle while pumping Speci cation MIL-PRF-83282 hydraulic uid into the system.

g. Monitor the sight gage on the No. 2 system reservoir.

h. Release the selector valve handle when the hydraulic uid reaches the FULL 0 PSIG mark on the sight gage.

i. Disconnect the service cart and replace the cap on the ground ll connector.

j. Close the ground ll connection access door.

3.4.5 No. 3 Hydraulic System Servicing. (See Figure 3-9 and Figure 3-10.) Service the system in accordance with the following procedures. The reservoir uid capacity is as follows:

SYSTEM RESERVOIR CAPACITY - US GAL REFILL CAPACITY - US

GAL

AF68-0213, AF68-0216, and

AF69-0024

5.70 1.54

AF83-1285 and up 5.9 1.4

a. Ensure that the ight controls are faired before servicing the No. 3 hydraulic system.

b. Reduce system pressure to zero PSIG.

c. Open the ground ll connection access door.

d. Connect a hand-operated hydraulic service cart to the ground ll connection.

e. Position the selector valve handle in service center No. 3 to ll No. 3 system reservoir.

f. Depress and hold the selector valve handle while pumping Speci cation MIL-H-83282 hydraulic uid into the system.

g. Monitor the sight gage on the No. 3 system reservoir.

h. Release the selector valve handle when the hydraulic uid reaches the FULL 0 PSIG mark on the sight gage.

i. Disconnect the service cart and replace the cap on the ground ll connector.

j. Close the No. 4 hydraulic servicing panel and remove equipment from the area if external servicing was accomplished.

3.4.6 No. 4 Hydraulic System Servicing. (See Figure 3-9 and Figure 3-10.) Service the system in accordance with the following procedures. The reservoir uid capacity is as follows:

SYSTEM RESERVOIR CAPACITY - US GAL REFILL CAPACITY - US

GAL

AF68-0213, AF68-0216, and

AF69-0024

10.01 2.70

AF83-1285 and up 10.7 2.7

a. Ensure that the following items are accomplished before servicing the No. 4 hydraulic system:

(1) Flight control faired.

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(2) Cargo doors closed in accordance with TO 1C-5M-2-12, Chapter 2 and TO 1C-5M-2-12, Chapter 3.

b. Reduce system pressure to 0 PSIG.

c. Open the ground ll connection access door.

d. Connect a hand-operated hydraulic service cart to the ground ll connection.

e. Position the selector valve handle in service center No. 3 to ll No. 4 system reservoir.

f. Depress and hold the selector valve handle while pumping Speci cation MIL-H-83282 hydraulic uid into the system.

g. Monitor the sight gage on the No. 4 system reservoir.

h. Release the selector valve handle when the hydraulic uid reaches the FULL 0 PSIG mark on the sight gage.

i. Disconnect the service cart and replace the cap on the ground ll connector.

j. Close the ground ll connection access door.

3.5 MLG SYSTEM SERVICING.

The following tools and test equipment are required for MLG system servicing.

NOTE

Failure of MLG to fully contact kneeling collars during kneeling operation is not an indication of an internal problem with the MLG. Due to high frictional forces internal to the MLG and individual servicing of the MLG in service, it is possible for the gear to be serviced correctly and not contact the collars. It is recommended that personnel verify that the aircraft is on a level parking spot, properly con gured, and that the NLG is properly serviced, prior to attempting to correct the servicing of the MLG. It is also recommended that the aircraft be fully jacked and all gear serviced at the same time to alleviate any side loading and additional friction effects on the gear.

Table 3-2. Tools and Test Equipment Required

Figure and Index No.

Nomenclature AN Type Designation or Part No.

Alternate Use and Application

Trailer, Compressed Gas Cylinder

Model MD-3 NSN 2330-00- 541-1385

Equivalent nitrogen source

To in ate landing gear strut, tires, accumula-tors, pitch positioner.

Gage, Dial Indicating 0 to 3,000 PSI mini-mum

MIL-DTL-8348 Equivalent gage con-forming to MIL-

DTL-8348

To check landing gear.

Gage, 0 to 400 PSI 236D100-3 NSN 6685-00- 440-7183

PN 3648C NSN 4910-

00-640-4188 or equivalent

To check tire pressure.

Gaseous Nitrogen A-A-59503, Type 1, Class 1, Grade B

To pressurize struts and accumulators.

3.5.1 MLG Shock Strut Fluid Servicing. (See Figure 3-11.)

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• Ensure that the area under the fuselage, wings, engines, and horizontal stabilizer is clear of all platforms and equipment ; unless airplane is fully jacked using complete fuselage mode. Failure to comply could result in injury to personnel or damage to the airplane or equipment.

• Failure to fully jack airplane when servicing all struts simultaneously may result in injury to personnel or damage to the airplane.

If the affected gear being serviced is an aft gear and the airplane is off jacks, kneel the opposite forward gear in accordance with instructions in TO 1C-5M-2-10CL-1, or stabilize airplane using two jacks in accordance with Chapter 2. Failure to comply could cause the airplane to fall or tip onto the de ated strut causing damage to the airplane.

NOTE

• Both forward gears may be simultaneously depressurized if both aft gears are unknelt and serviced. Both aft gears may be simultaneously depressurized if both forward gears are unknelt, serviced and airplane is stabilized using two jacks at the aft fuselage jack points in accordance with Chapter 2 .

• Servicing of all struts simultaneously is permitted only when airplane is fully jacked. When servicing the NLG shock strut, refer to NLG Shock Strut Fluid Servicing in this chapter.

a. Ensure secondary chamber is serviced to 2,350 (±100) PSI.

b. Remove the valve cap (1) from the high pressure valve at the top of the strut.

There are two nuts on the valve assembly. Do not turn the nut that has safety wire attached. This nut loosens the valve assembly which can blow out explosively and result in injury to personnel if loosened while pressure is in the strut.

NOTE

Hose assembly may be made using a straight or 90-degree No. 4 hose end and a minimum of 10 feet of No. 4 hose.

c. Install a high pressure air chuck and hose assembly on the high pressure valve and place the loose end of the hose into a container suitable to collect the hydraulic uid as it is released. Loosen the swivel nut (2) a maximum of 2-1/2 turns counterclockwise to slowly discharge the chamber. The rate of discharge is established by the amount the nut is loosened.

d. Jack the strut to obtain an X dimension of 7.375 (+0.125, 0.000) inches. (See Figure 3-11.)

e. Mark position of tting (7). Remove bolt (6) and remove tting (7) from the top of the strut.

f. Fill the strut to the level of the ller hole with Speci cation MIL-PRF-83282 hydraulic uid.

g. Lower the strut piston and remove the jack.

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Ensure that the valve tting installed in Step h is installed in its original indexed position. Failure to comply could result in injury to personnel or damage to equipment.

h. Install new packing (8) and insert the bolt (6) through the tting (7). Install the O-ring (9), then reinstall the tting.

Ensure the complete assembly is properly oriented. Tighten the bolt (6) to 70 (±10) inch-pounds and safety-wire the bolt.

NOTE

• Use clean dry nitrogen per A-A-59503, Type 1, Class 1, Grade B (or better) to service the MLG shock strut. If anything other than dry nitrogen as speci ed is used, an AFTO Form 781A entry must be made re ecting the condition and type of service accomplished. Upon return to home station the shock strut shall be reserviced in accordance with this paragraph and rein ated with clean dry nitrogen as speci ed.

• During the pressure stabilization period, gas entrainment occurs. Gas entrainment is the dispersion of gas into the hydraulic uid under pressure, resulting in a net loss of gas volume against the uid in the strut. When a strut is depressurized, the uid will desaturate and is indicated by gas bubbling from the uid that may persist for up to one hour or more. This is normal and should be considered when adjusting strut uid levels.

i. Attach Pressure Gage to the strut air valve. Attach the hose from the nitrogen cart to the pressure gage.

Safety goggles or face shield shall be worn by nitrogen servicing personnel. Failure to comply could result in injury to personnel.

j. Loosen the swivel nut (2) a maximum of 2-1/2 turns counterclockwise and in ate the strut primary (upper) chamber in accordance with the chart on the instructions plate (380 PSI with strut fully extended).

k. Tighten the swivel nut (2) to a torque value of 60 (±10) inch-pounds.

Do not remove the pressure source until the swivel nut is tightened and the pressure source is turned off. The servicing hose must be bled of pressure before disconnecting from valve. Failure to comply could result in injury to personnel or damage to equipment.

l. Turn off the servicing unit, bleed the servicing hose, and disconnect the hose.

m. Check for leaks using Speci cation MIL-PRF-25567 leak detection compound.

n. Replace the valve cap (1) and tighten nger tight.

3.5.2 MLG Shock Strut Deflation Procedure. (See Figure 3-11.)

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• Ensure that the area under the fuselage, wings, engines, and horizontal stabilizer is clear of all platforms and equipment; unless airplane is fully jacked using complete fuselage mode. Failure to comply could result in injury to personnel or damage to the airplane or equipment.

• Failure to fully jack airplane when servicing all struts simultaneously may result in injury to personnel or damage to the airplane.

• Do not loosen or remove the valve body or valve core to exhaust nitrogen charge. All pressure must be released before removal or the valve body or valve core; if not, those parts may be blown out with a force that may cause serious injury.

If the affected gear being serviced is an aft gear and the airplane is off jacks, kneel the opposite forward gear in accordance with instructions in TO 1C-5M-2-10CL-1, or stabilize airplane using two jacks in accordance with Chapter 2. Failure to comply could cause the airplane to fall or tip onto the de ated strut causing damage to the airplane.

NOTE

• Both forward gears may be simultaneously depressurized if both aft gears are unknelt and serviced. Both aft gears may be simultaneously depressurized if both forward gears are unknelt, serviced and airplane is stabilized using two jacks at the aft fuselage jack points in accordance with Chapter 2.

• For routine de ation of both primary and secondary chambers, de ate the primary rst followed by the sec-ondary chamber. When de ating the strut to compress the lower piston for shipping, de ate the secondary chamber rst followed by the primary chamber.

a. De ate MLG Shock Strut Primary (Upper) Chamber as follows:

Rapid release of the air charge may cause hydraulic oil in the chamber to atomize during de ation. Safety goggles or face shield shall be worn by nitrogen servicing personnel. Failure to comply could result in injury to personnel.

(1) Remove the valve cap (1) from the high pressure valve at the top of the strut.

There are two nuts on the valve assembly. Do not turn the nut that has safety wire attached. This nut loosens the valve assembly which can blow out explosively and result in injury to personnel if loosened while pressure is in the strut.

NOTE

Hose assembly may be made using a straight or 90-degree No. 4 hose end and a minimum of 10 feet of No. 4 hose.

(2) Install a high pressure air chuck and hose assembly on the high pressure valve and place the loose end of the hose into a container suitable to collect any hydraulic uid as it is released.

(3) Loosen the 3/4-inch hex swivel nut (2) a maximum of 2 1/2 turns counterclockwise to slowly discharge the chamber. The rate of discharge is established by the amount the nut is loosened.

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(4) When the nitrogen charge is completely released, the valve body can be loosened and removed from the shock strut.

b. De ate MLG Shock Strut Secondary (Lower) Chamber as follows:

Rapid release of the air charge may cause hydraulic oil in the chamber to atomize during de ation. Safety goggles or face shield shall be worn by nitrogen servicing personnel. Failure to comply could result in injury to personnel.

NOTE

The secondary chamber is serviced with 15 cubic inches (approximately 8 ounces) of MIL-PRF-7870 lubricating oil during build-up. This oil may be expelled during de ation. If it is necessary to replenish the secondary chamber, service using 8 ounces of MIL-PRF-83282 hydraulic uid through the servicing block port.

(1) Remove the valve cap (1) from the high pressure valve at the lower aft side of the strut.

There are two nuts on the valve assembly. Do not turn the nut that has safety wire attached. This nut loosens the valve assembly which can blow out explosively and result in injury to personnel if loosened while pressure is in the strut.

(2) Install a high pressure air chuck and hose assembly on the high pressure valve and place the loose end of the hose into a container suitable to collect any hydraulic uid as it is released.

(3) Loosen the 3/4-inch hex swivel nut (2) a maximum of 2 1/2 turns counterclockwise to slowly discharge the chamber. The rate of discharge is established by the amount the nut is loosened

(4) When the nitrogen charge is completely released, the valve body can be loosened and removed from the shock strut.

3.5.3 MLG Shock Strut Primary (Upper) Chamber Inflation Procedure. (See Figure 3-11.) Use the following proce-dure to in ate the shock strut primary chamber.

Ensure that the area under the fuselage, wings, engines, and horizontal stabilizer is clear of all platforms and equipment; unless airplane is fully jacked using complete fuselage mode. Failure to comply may result in injury to personnel or damage to the airplane or equipment.

a. Ensure secondary chamber is serviced to 2,350 (±100) PSI.

b. Remove the valve cap (1) from the valve at the top of the strut.

NOTE

Use clean dry nitrogen per A-A-59503, Type 1, Class 1, Grade B (or better) to service the MLG shock strut. If anything other than dry nitrogen is used, an AFTO Form 781A entry must be made re ecting the condition and type of service accomplished. Upon return to home station, the shock strut shall be reserviced in accordance with the paragraph titled MLG Shock Strut Fluid Servicing in this chapter and rein ated with clean dry nitrogen as speci ed.

c. Attach Pressure Gage to the strut valve. Attach the hose from the nitrogen cart to the gage.

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• There are two nuts on the valve assembly. Do not turn the nut that has safety wire attached. This nut loosens the valve assembly, which can blow out explosively and result in injury to personnel if loosened while pressure is in the strut.

• Safety goggles or face shield shall be worn by nitrogen servicing personnel. Failure to comply could result in injury to personnel.

• Do not overpressurize the shock strut. While performing Step c, monitor the source pressure gage and Servic-ing Gage. If, at any point, either gage indicates a pressure greater than the desired pressure, stop servicing immediately and determine the cause. Failure to comply could result in catastrophic failure of the MLG shock strut causing injury or death to personnel and/or severe damage to equipment.

d. Loosen the swivel nut (2) a maximum of 2-1/2 turns counterclockwise and in ate in accordance with the chart on the instruction plate or Figure 3-11. If X dimension cannot be obtained, check strut uid level.

e. Tighten the swivel nut (2) to a torque value of 60 (±10) inch-pounds.

Do not remove the pressure source until the swivel nut is tightened and the pressure source is turned off. The servicing hose must be bled of pressure before disconnecting from valve. Failure to comply could result in injury to personnel or damage to equipment.

f. Turn off the servicing unit, bleed the servicing hose, and disconnect the hose.

g. Check for leaks using Speci cation MIL-PRF-25567 leak detection compound.

h. Replace the valve cap (1) and tighten nger tight.

3.5.4 MLG Shock Strut Secondary (Lower) Chamber Inflation Procedure. (See Figure 3-11.) Use the following procedure to in ate the shock strut secondary chamber.

Ensure that the area under the fuselage, wings, engines, and horizontal stabilizer is clear of all platforms and equipment; unless airplane is fully jacked using complete fuselage mode. Failure to comply may result in injury to personnel or damage to the airplane or equipment.

a. Remove the valve cap (1) from the valve at the lower aft side of the strut.

NOTE

• Use clean dry nitrogen per A-A-59503, Type 1, Class 1, Grade B (or better) to service the MLG shock strut. If anything other than dry nitrogen as speci ed is used, an AFTO Form 781A entry must be made re ecting the condition and type of service accomplished. Upon return to home station the shock strut shall be reserviced in accordance with the Paragraph 3.5.1 and rein ated with dry nitrogen as speci ed.

• Servicing pressure gage should indicate a maximum of 50 PSI per smallest scale division, be capable of an accuracy of at least ±50 PSI and should not exceed 5,000 PSI max full scale range for this application.

b. Attach Pressure Gage to the strut valve. Attach the hose from the nitrogen cart to the pressure gage.

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• Safety goggles or face shield shall be worn by nitrogen servicing personnel. Failure to comply could result in injury to personnel.

• There are two nuts on the valve assembly. Do not turn the nut that has safety wire attached. This nut loosens the valve assembly, which can blow out explosively and result in injury to personnel if loosened while pressure is in the strut.

• Do not overpressurize the shock strut. Failure to comply could result in catastrophic failure of the MLG shock strut causing injury or death to personnel and/or severe damage to equipment.

c. Loosen the swivel nut (2) to a maximum of 2-1/2 turns counterclockwise and in ate the strut to 2,350 (±100) PSI while monitoring the source pressure gage and Servicing Gage. If, at any point, either gage indicates a pressure greater than the desired pressure, stop servicing immediately and determine the cause.

d. Tighten the swivel nut (2) to a torque value of 60 (±10) inch-pounds.

Do not remove the pressure source until the swivel nut is tightened and the pressure source is turned off. The servicing hose must be bled of pressure before disconnecting from valve. Failure to comply could result in injury to personnel or damage to equipment.

e. Turn off the servicing unit, bleed the servicing hose, and disconnect the hose.

f. Check for leaks using Speci cation MIL-PRF-25567 leak detection compound.

g. Replace the valve cap (1) and tighten nger tight.

3.5.5 Landing Gear Tire Cold Weather Servicing.

NOTE

Tire air pressure will decrease somewhat as the temperature drops. Excessive de ation could indicate cold weather leakage at the tire air valve or tire seal. Avoid unnecessary pressure checks.

a. Check tires for excessive de ation.

b. When pressure checking tires in cold climates, always apply heat to air valves and surrounding areas before unseating valve seal.

c. Continue application of heat during rein ation to ensure air valve seal exibility when valve closes.

d. Do not allow tires to stand in snow soaked with jet fuel or on fuel covered ramp areas.

3.5.6 MLG Tire Servicing Procedures.

To prevent damage to eyes when checking pressure during in ation/de ation of tires, adequate eye protection must be used. Failure to comply could result in injury to personnel.

a. Remove valve cap and check tire pressure with a 0- to 400-PSI gage.

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• Ensure that servicing pressure does not exceed 250 PSI. Failure to comply could result in injury to personnel.

• Comply with all applicable requirements of TO 4T-1-3, TO 00-25-172, and TO 35D3-1-101. Stand forward or aft of the tire being serviced. Ensure that the hose is fully extended if the servicing kit is used. Failure to comply could result in injury to personnel and damage to equipment.

NOTE

• When nitrogen service units are not available, tires may be in ated with a low pressure air compressor.

• If low tire pressure is required for substandard air eld operations, see Figure 3-12.

b. When servicing tires on the ight line, use a Speci cation MIL-I-85352 tire in ation assembly. In ate tires using a nitrogen cart or other equivalent nitrogen source.

c. The standard in ation pressure for MLG tire servicing is 145 (±5) PSIG. Service in accordance with Table 3-3.

Table 3-3. Normal Tire Servicing Requirements

Tire Pressure Required Action Condition

NOTE

No additional tire changes required unless close inspection reveals further damage.

Below 70 PSIG If airplane has been towed or taxied, remove and replace tire and tag in accor-dance with criteria in TO 4T-1-3. If airplane has not been towed or taxied, in ate tire to 145 (±5) PSIG and continue in service after tire passes a 12-hour leak check. Leak check must be accomplished before tire returns to ser-vice.

Between 70 and 144 PSIG In ate to 145 (±5) PSIG Between 145 and 150 PSIG No action Over 150 PSIG Determine cause(s) of high pressure readings. Extreme caution should be used.

High pressure could be from hot tires. If tires are not hot when touched, de-ate to 145 (±5) PSIG. If tires are hot to touch, no pressure adjustment is nec-essary until airplane has reached a base where time permits tires to reach am-bient temperature. If a difference of 10 PSIG is detected between tires, the pressure will be equalized to highest tire pressure.

The servicing hose must be bled of pressure before disconnecting from valve. Failure to comply could result in injury to personnel or damage to equipment.

d. Turn off nitrogen source, bleed servicing hose, and disconnect hose.

e. Replace valve cap and tighten nger tight.

3.5.7 Precharging the Parking Brake Accumulator. (See Figure 3-13.) The parking brake accumulator is located on the right side of the cargo compartment aft of FS 1303. Service the accumulator as follows:

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NOTE

Use clean dry nitrogen per A-A-59503, Type 1, Class 1, Grade B (or better) to service the parking brake accumu-lator. If anything other than dry nitrogen as speci ed is used, an entry must be made onto AFTO Form 781A re ecting the condition and type of service accomplished. Upon return to home station the accumulator shall be reserviced in accordance with this paragraph and rein ated with clean dry nitrogen as speci ed. All personnel involved in nitrogen servicing shall be in communication.

a. Ensure that hydraulic system No. 4 power is off.

b. Reduce the hydraulic uid pressure to zero by pumping the brake pedals.

NOTE

Servicing pressure gage should indicate a maximum of 10 PSI per smallest scale division, be capable of an accuracy of at least ±20 PSI and should not exceed 1,500 PSI max full scale range for this application.

c. Attach Servicing Gage to accumulator valve.

Safety goggles or face shield shall be worn by nitrogen servicing personnel. Failure to comply could result in injury to personnel.

d. Attach hose from nitrogen cart to servicing gage.

There are two nuts on the valve assembly. Do not turn the nut that has safety wire attached. This nut loosens the valve assembly which can blow out explosively and result in injury to personnel if loosened while pressure is on the unit.

e. Loosen swivel nut (5) a maximum of 2-1/2 turns counterclockwise for desired ow.

If accumulator piston is not fully bottomed prior to nitrogen precharging, emergency braking capability may be reduced. Failure to comply could result in injury to personnel or damage to equipment.

f. With nitrogen servicing pressure applied, pump brake pedals several times to bottom out piston.

Park brake accumulator nitrogen servicing must be veri ed by a certi ed pressure gage. The pressure gages installed on the components being serviced are for reference only and are not for servicing. Improper servicing can result in damage to the parking brake accumulator.

g. Recharge accumulator to precharge pressure given on chart (Figure 3-13) for existing ambient temperature. Ensure pressure readings on installed gage and servicing gage are the same, if not replace accumulator pressure gage.

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Do not remove the pressure source until the swivel nut is tightened and the pressure source is turned off. The servicing hose must be bled of pressure before disconnecting from valve. Failure to comply could result in injury to personnel or damage to equipment.

h. Retighten the swivel nut to a torque value of 60 (±10) inch-pounds when the desired pressure is obtained.

i. Turn off the service unit, bleed hose of pressure, disconnect from servicing gage.

j. Disconnect servicing gage from accumulator valve.

k. Check for leaks using Speci cation MIL-PRF-25567 leak detection compound.

l. Replace the valve cap and tighten nger tight.

3.5.8 Precharging the Pitch Positioner. (See Figure 3-14.) There is a pitch positioner on each of the four MLG bogie beams. The positioner is on the inboard side of the bogie. Service the positioner as follows:

NOTE

Use clean dry nitrogen per A-A-59503, Type 1, Class 1, Grade B (or better) to service the pitch positioner. If anything other than dry nitrogen as speci ed is used, an entry must be made onto AFTO Form 781A re ecting the condition and type of service accomplished. Upon return to home station the pitch positioner shall be reserviced in accordance with this paragraph and rein ated with clean dry nitrogen as speci ed. All personnel involved in nitrogen servicing shall be in communication.

a. Check the pressure gage on the positioner. Verify that the gage pressure is equal to the pressure speci ed in Figure 3-14 (+50, -150 PSIG) for the existing ambient temperature.

b. Remove the valve cap.

NOTE

Servicing pressure gage should indicate a maximum of 10 PSI per smallest scale division, be capable of an accuracy of at least ±50 PSI and should not exceed 3,000 PSI max full scale range for this application.

c. Attach Servicing Gage to positioner valve.

Safety goggles or face shield shall be worn by nitrogen servicing personnel. Failure to comply could result in injury to personnel.

d. Attach hose from nitrogen cart to servicing gage.

There are two nuts on the valve assembly. Do not turn the nut that has safety wire attached. This nut loosens the valve assembly which can blow out explosively and result in injury to personnel if loosened while pressure is on the unit.

e. Loosen the swivel nut (4) a maximum of 2-1/2 turns counterclockwise for the desired ow.

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Pitch positioner nitrogen servicing pressure must be veri ed by a certi ed pressure gage. The pressure gages installed on the components being serviced are for reference only and are not for servicing. Improper servicing can result in damage to the MLG during retraction.

f. Recharge the positioner to precharge pressure given on the chart (Figure 3-14) for existing ambient temperature.

Ensure pressure readings on the installed gage and the servicing gage are the same, if not replace the positioner pressure gage.

Do…