A. LOADING GENERALITIES
6.3. Tie-down computation
6.3.1. 3.1 Tie-down equipment
a) Breaking strength
The breaking strength for a lashing or a tie-down fitting represents the maximum load that the item shall withstand without failure. Only equipment for which the breaking strength is ascertained should be used.
b) Lashing equipment
Different types of equipment can be used for lashing: nets, cables, ropes or straps. Lashing equipment must indicate permanently the maximum breaking strength, except when the restraint equipment is part of a pallet or an aircraft compartment (pallet nets and divider nets).
c) tie-down fittings
Airbus cargo hold floors are equipped with tie-down points enabling quick fastening of small rings
only (single stud fittings). Only the tie down points which are not required for net fastening may
be used for restraint of packages.
The maximum breaking strength of a single stud fitting is 900 kg (2000 lb).
Heavy rings (double stud fittings), can not be used for direct tie-down on the cargo floor, but for
tie-down on pallet‘s or container‘s rims.
The maximum breaking strength for a double stud fitting is 2270 kg (5000 lb).
LOADING LOADING
A. LOADING GENERALITIES
6.3.2. General tie-down recommendations
. It is prohibited to tie-down a load with different lashing equipment (straps and ropes as an example).
. Single stud fittings and ropes can be used in case of absolute necessity, when no other equipment is available, for tie-down in bulk compartments or inside containers.
. Tie-down shall ensure restraint in the forward, aft, up, left and right directions. With a standard lashing, lateral tie-down is generally covered if tie-down in the forward, aft and up directions is adequately performed except for irregular shape loads and for high CG loads.
. A minimum distance between two tie-down points shall be respected (generally 30 cm between two single stud fittings and 50 cm between two double stud fittings).
. Each strap or rope shall make a maximum angle of 30 degrees with the direction of restraint (e.g. αΑ, αF, δ, βA, βF).
αA = Floor angle
(Restraint in the AFT direction)
α
F = Floor angle
(Restraint in the FWD direction)
δ
L / R = Wall angle Left / Right
(Restraint in the UP direction)
Wall angle Left / Right
β
A L / R =
(Restraint in the AFT direction)
β
F L / R = Wall angle Left / Right (Restraint in the FWD direction)
. It is prohibited to use two ropes or straps attached to the same tie-down point and restraining the load in the same direction.
A. LOADING GENERALITIES
6.3.3. Standard lashing
A standard lashing consists into four straps or ropes (2 Up, 1 Forward, 1 Aft), attached to 4 tie-down points (2 on each side of the piece in the flight direction). This basic pattern solves most of the lashing problems. A security rope may be used to maintain straps in correct position and prevent them from slipping down.
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