{"id": "hull_m", "code": "HX-M", "name": "Coque cargo moyen", "description": "Cargo 2 colonnes × 3 rangs : 6 slots C1, épine centrale à bras de serrage doubles, 3 tuyères.",
 "rows": [["C1", "C1"], ["C1", "C1"], ["C1", "C1"]], "fore_len": 5.0, "aft_len": 3.4, "keel_h": 1.60, "engines": 3, "skid_h": 1.00}