TM 1-1500-250-23
3-1
Change 4
CHAPTER 3
TIE-DOWN PROCEDURES
3-1.
General Tie-Down Procedures. Line ten-
sion tie-down lines from all main rotor blades shall
be taut, but care must be taken to ensure excessive
deflection of blades below the static jacking, droop
position, as stated in the specific aircraft -23 TMs,
is not exceeded.
3-2.
Specific Aircraft Tie-Down.
a.
OH-58D tie-down blades as specified in the
-23 Technical Manual and as shown in figure 3-1 of
this general TM. Use the polyester rope referenced
in this manual.
b. OH-58A/C tie-down blades as specified in
the -23 Technical Manual and as shown in Figure
3-2 of this general TM. Securely tie the straps of the
boot to the polyester rope near the boot. Ensure the
ropes are long enough to cross and tie in the posi-
tion illustrated. The forward blade shall be tied down
using the same boot strap/rope arrangement de-
vice. The ropes shall be tied to the forward eyebolts
of the landing skid. The ropes, as an option, can be
secured to the forward eyebolts of the landing skid
by either tying or using a self closing hook that is the
same strength or as strong as the polyester rope, to
anchor tie-down rope to the skid rings.
NOTE
Optional tie-down procedure for the OH-58A/C
is applicable also to the UH-1 and AH-1 aircraft.
c.
AH-64 tie-down blades as specified in the
-23 Technical Manual and as shown in figure 3-3 of
this general TM. Ensure that the main rotor blade
tie-down boot is in good repair and that the two ny-
lon end straps are securely attached (refer to figure
3-3, blow-up). Replace the 3/8 inch nylon rope with
polyester rope. 3/8 inch diameter standard polyes-
ter rope can be substituted directly. 1/2 inch diame-
ter standard polyester rope can be secured to the
boot by forming a small loop with the existing nylon
rope and tying the polyester rope to the loop. En-
sure that the rope is long enough to reach the proper
aircraft hardpoints. The right aft boot must have an
additional length of rope to secure to the aft out-
board wing pylon sway brace or to secure to the aft
wing store suspension lug. The other rope attaches
to the aft jacking fitting at FS 450. This configuration
will prevent the boot from slipping off.
d.
UH-60 tie-down blades as specified in the
-23 Technical Manual and as shown in figure 3-4 of
this general TM. To prevent damage from the lock
release cable in strong winds, wrap the cable sever-
al times around the tie-down rope and slip the end
loop through one of the cable wraps.
e.
AH-1 tie-down blades as specified in the -23
Technical Manual and as shown in figure 3-5 of this
general TM. Engage hook of main rotor tie-down in
hole of fitting on each rotor blade and position blade
above tailboom. Pul on tie-down to remove span-
wise slack from the rotor system and secure rotor
blade by wrapping the tie-down rope firmly around
tailboom as shown in figure 3-5. Tie forward tie-
down rope to tow rings, as shown in figure 3-5, on
landing gear skid. Additional security of main rotor
tie-down can be accomplished by inserting an
AN416-2 safety retaining pin through a 0.060 inch
hole drilled through the hook of the main rotor tie-
down. The hole is drilled perpendicular to the plane
of the handle, 0.25 inch from the insertion end of the
hook. Secure the safety retaining pin to the hook
handle with a 6-inch piece of NAS1455B30-6P
chain and safety wire. Insert the safety retaining pin
through the hook after inserting the hook through
the rotor blade fitting. In the final tie-down position,
the blades must be in a level position.
f.
UH-1 tie-down aft blades as specified in the
-23 Technical Manual and as shown in figure 3-6 of
this general TM. Engage hook of main rotor tie-
down in hole of fitting on each rotor blade and posi-
tion blade above tailboom. Pull on tie-down to re-
move spanwise slack from the rotor system and
secure rotor blade by wrapping the tie-down rope
firmly around tailboom as shown in figure 3-6. Tie
forward rope tie-down rope to tow rings, as shown
in figure 3-6, on landing gear skid. Additional securi-
ty of main rotor can be accomplished by inserting an
AN416-2 safety retaining pin through a 0.060 inch
hole drilled through the hook of the main rotor tie-
down. The hole is drilled perpendicular to the plane
of the handle, 0.25 inch from the insertion end of the
hook. Secure the safety retaining pin to the hook
handle with a 6-inch piece of NAS1455B30-6P
chain and safety wire. Insert the safety retaining pin
through the hook after inserting the hook through
the rotor blade fitting. In the final tie-down position,
the blades must not exceed 6 inches of additional
droop from having been pulled down. This applies
to both metal and composite blades.
g.
CH-47 tie-down blades as specified in -23
Technical Manual and figures 3-7 or 3-7a of this
general TM. Use figure 3-7 for normal aircraft tie-
down. As an option, the CH-47 blades may be se-
cured to the mooring pad hardpoints, as shown in
figure 3-7a, provided the aircraft is secured using
the mooring procedures in this TM.