B. Nose Lift Dolly - G8950, Mercer Robinson, Div. of Squibb Machine and Tool Co., Easton, Pennsylvania 18043 (used to lift 78 inches maximum)
C. Nose and Main Landing Gear Ground Lockpins - F72735
3. Prepare to Tilt Airplane
A. Defuel airplane to approximately 6000 pounds of fuel (Ref 12-11-0).
B. Drain potable water and waste water tanks (Ref 12-14-0 and 12-7-0).
C. Restrain nose shock strut with nylon strap, rope, sling or other suitable means so that dimension X, Fig. 203, is 22 inches maximum. Refer to 12-15-41 for inflation nose shock strut.
D. Check that main gear shock struts are serviced to 1-1/2 +1/8 inches extension (Ref 12-15-31).
500
May 20/82 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. 7-13-0 Page 201
E. Determine how high nose must be lifted to gain required tail clearance. (See figure 202.)
CAUTION: NOSE SHOULD NOT BE LIFTED MORE THAN 84 INCHES. FAILURE TO COMPLY COULD DAMAGE AIRPLANE.
F. Center airplane nose landing gear.
G. If using hose lift dolly D1000, install 4-inch collar around nose gear exposed inner cylinder to prevent excessive compression of nose gear inner cylinder. This will prevent damage to lower fuselage by contact with lift dolly.
H. Remove rear lock bar from the dolly and roll dolly into position centered on the nose gear.
I. Disconnect nose gear torque links and install dolly lock bar behind tires.
Nose Lift Dolly 500
7-13-0 Figure 201 Feb 15/73
Page 202
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
G53203
500 Vertical Tail Height VS Nose Gear Jacking Height
Feb 15/73 Figure 202 7-13-0
Page 203
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
4. Tilt Airplane
A. Check that all landing gear downlocks are installed.
B. Loosely chock main landing gear wheels.
C. Ensure that airplane brakes are released.
D. Raise nose to the required uplock on the dolly. Operate gear scoop "down" to settle securely in the uplocks.
E. Ensure that strut extension (dimension X) has not increased to more than 22 inches. If dimension X is exceeded release strut pressure until dimension X is 22 inches or less. Readjust restraints.
CAUTION: IF STRUT EXTENSION (DIMENSION X) IS MORE THAN 22 INCHES DO NOT ATTEMPT TO TOW AIRPLANE. THE NOSE GEAR CENTERING CAMS CAN BE DAMAGED IF THIS CONDITION EXISTS.
5. Balance Check for Towing Tilted Airplane
A. As the airplane is rotated into a tilted position the center of gravity moves aft with respect to the main gear axle. This aft movement, plus the adverse effects or wind, upgrades, and fuel movement due to tilting, could cause the airplane to tip and the aft fuselage settle on, or momentarily touch the ground. Therefore, a balance check form must be filled out to ensure that the airplane will not be overbalanced when tilted. If it is determined that the airplane will tip, either add forward ballast to counter the overbalance or restrain nose gear wheels to lift dolly so the dolly acts as ballast.
Nose Gear Shock Strut Extension 500
7-13-0Page 204 Figure 203 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. May 01/76
B. The balance check consists of adding moments about the main gear due to airplane weight (Fig. 204), tilting airplane (Fig. 205), fuel shift (Fig. 206), wind (Fig. 207), tow vehicle acceleration (Fig. 208), and upgrades (Fig. 209). The sum of these moments is required to be more than +900,000 inch-pounds (+900 x 103 inch-pounds).
C. Any accumulation of snow or ice on the empennage should be removed before tilting or accounted for in the balance check.
D. Figure 212 presents the maximum nose gear load for tilted airplanes. The lift dolly must have capacity equal to maximum expected nose gear load.
E. Figure 213 provides a sample balance check for towing a tilted airplane, and Fig. 214 the tilt and clearance data.
6. Tow Airplane While Tilted
CAUTION: WITH THE AIRPLANE IN THE NOSE-UP ATTITUDE, SUDDEN STARTS CAN DAMAGE THE NOSE GEAR OLEO. TOW AIRPLANE SMOOTHLY AVOIDING SUDDEN STARTS AND STOPS. DO NOT MAKE SHARP TURNS WHILE TOWING A TILTED AIRPLANE.
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