PAPI Installations
One row per runway end. Units per installation = boxes per bar × sides. Choose "Both" sides for a bar on each side of the runway; the cable and duct crossing the runway are added automatically. "Existing" CCR excludes a CCR from the BOQ (PAPI added to a circuit that already has capacity).
| # | Runway End | System | Sides | Lead-in (m) | Extra Duct (m) | CCR |
|---|
Lead-in = cable route length from the nearest AGL cable or vault to the first bar. CSV columns: runway_end, boxes (2 or 4), sides (1 or 2), leadin_m, duct_m, ccr (new / existing).
Construction Assumptions
Defaults are typical starting values, not manufacturer data. Replace them with your PAPI unit datasheet, project specification and cable data.
Loads a preset for lamps per unit and watts per lamp. Edit both in "Lamps & transformers" below to match the datasheet. For LED units, enter the unit's input VA (watts ÷ power factor) if the datasheet gives it, because the transformer is sized on this load.
Bill of Quantities
Add a runway end on the Calculate tab.
Material BOQ
Calculated / Nominal Quantity — not a Final BOQ Quantity. "Order qty" applies the allowance: counted items round up to whole pieces and measured items (m, m³, kg) round up to 2 decimals (3 for m³). Verify against the approved PAPI layout drawing and manufacturer data before issue.
Per-Installation Breakdown
How This Calculator Works
Each runway-end row is expanded into units, cable, trench, foundation and circuit quantities from geometry and the editable assumptions, then summed across the project.
Units and bar length
S is the spacing between adjacent units. The default is a typical value only; take the spacing from the applicable standard and your layout drawing. Each unit gets one isolating transformer, primary and secondary connector sets, frangible legs, a base and a foundation pad.
Primary cable, trench and duct
The inner-unit distance defaults to 15 m for a 4-box PAPI and 10 m for a 2-box APAPI (typical ICAO values; confirm against the applicable standard). A series circuit is a loop, so cable runs out and back (factor 2). The slack allowance is applied on top. The trench follows the single route; for both-sided installations a duct is added across the runway, plus any extra duct you enter per row.
Transformer selection
The transformer is the smallest standard size (45 / 65 / 100 / 150 / 200 / 300 / 500 W) not below the required VA.
CCR sizing
One dedicated CCR per runway-end row marked "New", selected from the standard sizes 4 / 7.5 / 10 / 15 / 20 / 25 / 30 / 50 / 70 / 100 kW. The check includes cable I²R loss. For a shared circuit, size the CCR with the CCR Selection & Loading calculator.
Foundation and structure
One concrete pad per unit (length × width × depth), reinforcement per m³, and legs, couplings, base plates and anchor bolts per unit. Excavation covers the trench (length × width × depth) and each foundation pit (pad volume, net); the sand bed comes from trench length × width × bed thickness.
What this calculator does not do
It does not locate the units, set the aiming angles or check obstacle clearance, and it does not price the BOQ. It does not size a shared circuit's CCR or check voltage drop on the series loop. Frangibility, wind loading and foundation design must be verified against the manufacturer's design.