KLM Royal Dutch Airlines Boeing 777-300ER seat map

Four-tier KLM long-haul stack on the refurbished Boeing 777-300ER: World Business Class (JAMCO Venture, 1-2-1, with a new sliding privacy door), Premium Comfort (2-4-2), Economy Comfort (extra-legroom zone within Economy) and Economy (3-4-3, 10-abreast). LAYOUT DERIVED_FROM_COUNTS: KLM's own aircraft page (klm.com) times out for automated fetch and KLM publishes no citable per-seat raster, so the row grid is a structural reconstruction from published counts (Wikipedia KLM fleet table NEUTRAL for the split; news.klm.com PRIMARY for the products), hence every cabin carries derived:true and layoutProvenance derived_from_counts. COUNTS (Wikipedia KLM fleet table): 16 airframes, 35 World Business / 24 Premium Comfort / 56 Economy Comfort / 266 Economy = 381; the 21-28 Premium Comfort seats-per-type range and fleet-wide 777/787 Premium Comfort rollout are confirmed by the KLM newsroom completion release. MODELLING: business is split into a forward WBC cabin (rows 1-6, 24 seats) and a small rear WBC cabin (rows 7-9, 11 seats); 35 does not divide evenly into 1-2-1 rows, so the final derived business row seats a window plus the centre pair (3 seats) with the K position given to a galley/closet monument. Premium Comfort is 2-4-2 on the wider 777 (unlike the 787-10's 2-3-2), 3 full rows of 8 = 24. Economy Comfort is modelled as a ZONE within the single Economy cabin per AUTHORING §6 (location-priced extra-legroom tier via seatTypeId economy-comfort, canonicalTier extra_legroom_economy, contributing the 56N token) — NOT a separate cabin: rows 14-18 full 10-abreast (50) plus a 6-seat exit row 19 at door 3 where the centre bank is interrupted by the cross-aisle (56 total). Standard Economy is rows 20-46 (266): rows 20-45 full 10-abreast except the pre-exit row 33 (limited recline ahead of the door-4 exit row 34, which carries extra legroom) and the near-galley row 45, plus a 6-seat last row 46 that narrows to two triples ahead of the aft galley/lavatories. DERIVATIONS / UNPUBLISHED: door and exit positions (doors 1-5), the over-wing span (rows 27-41), all partial-row narrowing, and all seat-type pitch/width/recline except the published 38-inch Premium Comfort pitch are structural estimates; row 13 is skipped per common KLM numbering. windowAlignment is left 'unknown' for window seats because the grid is derived and a real window cannot be proven to line up (no 777 window grid exists). PH-BVA is one representative registration of the 16-airframe subfleet (Wikipedia notes it as a 777-300ER in special orange livery).