ULD Build-Up for Narrow-Body Ops: A Practical Checklist

Narrow-body ULD build-up at Kuwait International Airport runs on a tighter envelope than wide-body work. Smaller containers, lower weight limits per ULD, less floor area in the cargo hold, and less margin for error on the load plan. Most of the belly-hold cargo moving through KWI on the regional and short-haul lanes is built up against this envelope, and the operations that go cleanly are the ones where the build-up team and the airline’s load planning team are aligned on the basics before the pallets reach the build-up bay. This post sets out the practical checklist the cargo desk works against — ULD types, weight limits, build sequence, tie-down standards, and the documentation handover.

The narrow-body ULD set

The aircraft types that drive narrow-body ULD build-up at KWI are the A320 family and the 737 family. The A320 family — A319, A320, A321 — accepts the AKH (LD3-45W) container in the forward and aft holds, plus loose-loaded bulk cargo in the bulk compartment at the rear. The A321 with the optional cargo loading system also accepts the AKH; the older A320 and A319 without the system are loose-load only. The 737NG and 737 MAX families are loose-load throughout the holds — no ULDs, all bulk. That distinction is the first thing to confirm at the planning stage: whether the inbound aircraft has the cargo loading system fitted at all, and which holds are container-capable.

The AKH is a half-width LD3 derivative — eight-foot floor footprint, contoured to the lower-deck shape of the A320 family. Maximum gross weight is typically 1,134 kg, though airline limits vary. The full-width LD3 sometimes seen on regional wide-bodies is not narrow-body equipment and is rarely seen at KWI on the A320 lane. The DPE pallet — a half-pallet for narrow-body floor loading — is occasionally specified by operators carrying outsized cargo on flexible aircraft; we build it on request but the standard narrow-body request is AKH or bulk.

Weight limits and the load plan

Maximum gross weight per ULD is the headline number, but the working limit is set by the airline’s weight and balance manual for the specific aircraft and hold position. The forward hold and the aft hold on a narrow-body have different floor strength ratings; the bulk compartment at the rear has its own limit again. The build-up team works against the load plan supplied by the airline’s load control team, and the load plan names the position-by-position limits that apply for the day.

Centre-of-gravity matters more on a narrow-body than a wide-body simply because the moment arms are shorter and the same weight further from the reference point shifts the index more. A heavy AKH in position 11 versus position 41 has a meaningful effect on the trim sheet. The build-up record names which AKH carries which gross weight, and the load planner allocates positions against that record. Loose-load bulk is summarised as a total weight in the bulk compartment with the centre of mass declared. The cargo handling team at KWI works to the airline’s load instruction report and returns the build-up record before the load is dispatched to the ramp.

The build-up sequence

The sequence the build-up team follows in the warehouse is consistent across the narrow-body operations at KWI:

• Pallet or container preparation. The empty AKH is inspected for serviceability — door operation, net condition, rail engagement points, ULD identification number visible. Damaged ULDs are tagged out and not built; the airline is notified to issue a replacement number against the load plan.
• Acceptance of cargo to the bay. Each consignment for the build is matched to the manifest line. Weights are verified against the air waybill; discrepancies are resolved before the cargo enters the build-up bay.
• Compatibility check. Where DG is in the build, the IATA segregation table is checked against the rest of the consignments going into the same ULD or the adjacent positions. Incompatible segregation is broken across multiple ULDs as required.
• Build sequence inside the ULD. Heavy items at the base, lighter on top, fragile material protected and oriented per shipper marks, perishables and live animals positioned for ventilation as required. Loose bulk is stacked against the bulkhead first and worked outwards.
• Net and tie-down. The cargo net is fitted and tensioned to the manufacturer’s specification. Loose-load positions are restrained against the airline’s tie-down standard for the aircraft type — typically a tie-down ratio matching the published manual.
• Final weighing and labelling. Each ULD is weighed on the warehouse scale; the gross weight is recorded against the ULD identification number on the build-up record. Position labels for the aircraft are applied per the load plan.

The sequence reads like an assembly line because that is what it is. The build-up team works against a printed load instruction report, ticks off each step on the build-up record, and signs the document at the end. The build-up record is the primary handover document to the ramp.

Tie-down and restraint

The tie-down inside an AKH is the cargo net plus the engagement of the ULD itself with the aircraft’s lock and rail system. The build-up team’s responsibility ends with the net correctly fitted; the lock and rail engagement is the ramp loadmaster’s responsibility at the aircraft. For loose-load bulk, restraint is the build-up team’s full responsibility. Straps, nets, and stanchions are deployed against the airline’s published tie-down diagram for the bulk compartment of the specific aircraft type. A loose-load configuration that passes the warehouse inspection but fails the ramp inspection has to be reworked at the aircraft side, which costs ground time and is a poor use of the operating window.

NOTOC, build-up record, and the ramp handover

The handover from build-up to ramp travels on three documents. The build-up record names every consignment in every ULD or bulk position with weight and seal number where applicable. The Notification to Captain — NOTOC — names every DG package on board with class, UN number, position, and net quantity per package. The load instruction report from load control names the position allocation. The ramp loadmaster works against all three. A clean handover means the three documents reconcile — same weights, same positions, same DG entries — without on-the-ramp recalculation.

If a build runs late and the ramp has to load against a partial document set, the most common failure is a NOTOC that reaches the flight deck after the doors are closed. The wider cargo handling workflow through the bonded warehouse is built specifically to avoid that compression — the build-up bays are sized so concurrent narrow-body builds do not stack against the same ramp window. We design the build-up timeline backwards from the published off-block time and target completion of the build no later than thirty minutes before the load is required at the aircraft side, so the ramp has the document set in hand before the aircraft is open for loading.

The takeaway for narrow-body operators

Narrow-body ULD build-up is unforgiving in a way that wide-body work is not — the aircraft is smaller, the load is smaller, and the timing window between scheduled on-block and scheduled off-block is shorter. The cleanest builds are the ones that work against a load plan supplied early, an accurate manifest, and a standing communication channel between the airline’s load control team and our cargo desk. Operators new to KWI on the narrow-body lanes can scope the build-up workflow against a specific schedule through the RFQ form and the desk will return a planning brief that names the equipment, the staffing, and the documentation timeline for the planned operation. The procedural detail above is the same playbook the team works against every shift.