Class Tonnage (t) Draught (m) Length (m) Width (m) Air draught (m) Description Class III 1,000 Class IV 1,000–1,500 2.5 80–85 9.5 5.2–7.0 Johann Welker[1] Class Va 1,500–3,000 2.5–2.8 95–110 11.4 5.2–7.0–9.1 Large Rhine[8] Class VIb 6,400–12,000 3.9 140 15 9.1 [8] Class VII 14,500–27,000 2.5–4.5 275–285 33.0–34.2 9.1 [8]