Article · Wikipedia archive · Last revised Jun 12, 2026

Straight-nine engine

The straight-nine engine is a piston engine with nine cylinders arranged in a straight line along the crankshaft. The most common application is for large diesel engines used by ships.

Last revised
Jun 12, 2026
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≈ 1 min
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Wikipedia ↗

The straight-nine engine (also referred to as an inline-nine engine, abbreviated as I9 or L9) is a piston engine with nine cylinders arranged in a straight line along the crankshaft. The most common application is for large diesel engines used by ships.

Examples of straight-nine engines include:

  • Rolls-Royce Bergen B, C and K series1
  • Wärtsilä RT-flex60C-B,2 RT-flex82C, RTA84T-D, RTA84C, RTA96C, 20, 26, 32, Wasa32LN, 38, 46 and 46F series
References

References

  1. "Historie om bedriften" [Company history]. FF klubben (in Norwegian).{{cite web}}: CS1 maint: deprecated archival service (link)
  2. "The Sulzer RT-fl ex Common-Rail System Described" (PDF). Wärtsilä. August 2004. p. 2. Retrieved 2025-01-24.