At 0250 local time on June 13, 2018, the inbound bulk carrier Yochow collided with the articulated tug and barge OSG Independence/OSG 243, which was moored at the TPC Group, Inc. facility on the Houston Ship Channel in Houston, Texas. The pilot on Yochow planned to turn wide at Sims Bayou, intending to stay to the south side of the channel to pass the dredge MBI 05 operating in the channel just past the turn. He ordered “hard starboard” to make the turn. The helmsman repeated the pilot’s order but immediately put the rudder hard to port. Ten seconds later, the pilot recognized the error and ordered midships while tapping with his fingers on the rudder angle indicator above his head to get the helmsman’s attention. It took the steering gear 15 seconds to shift from hard port to midships, and then the pilot repeated his original hard-starboard order. The rudder reached hard starboard 12 seconds later, although the ship’s heading was still falling to port at about 12 degrees per minute. With the port anchor and two shots of chain deployed, the Yochow collided at approximately 4.5 knots with the port side of the tank barge OSG 243 amidships at 02:49:45.
1 | Accident snapshot
| Collision time (CDT) | 02 : 50 |
| Manoeuvre | 70 ° starboard turn at Sims Bayou Turning Basin |
| Orders in the final minute | 02 : 47 : 35 “Hard-starboard”Helmsman replied correctly but put the rudder hard-port instead |
| Result | Yochow struck the moored tank barge OSG 243 at ≈ 4.5 kn; facility, barge and ship damage ≈ US $21 m; no injuries, no spill |
The pilot noticed the wrong helm only after about 10 s; by the time the rudder was centred and re-ordered to starboard, the vessel had left the channel and could not complete the turn.
2 | HOM cue relevant to this error
| Bridge cue (advisory) | Trigger* | Crew experience |
|---|---|---|
| WRONG HELM banner + one short audible signal | Rudder begins moving opposite to the spoken helm order | Immediate, unmistakable prompt: “Wheel is the wrong way—correct now.” |
The cue never locks controls or asks for an acknowledgement.
3 | Alternate timeline with HOM active
| Actual time | Real event | HOM cue | Likely bridge response |
|---|---|---|---|
| 02:47:35 | Pilot orders “Hard-starboard” | — | — |
| 02:47:37 | Wheel goes hard-port (error) | WRONG HELM banner + brief sound | Pilot & mate spot mismatch instantly; helm ordered to starboard |
| 02:47:50 | Rudder swinging hard-starboard | Banner clears automatically | Vessel resumes planned turning path, remains in channel |
| 02:50 | (Collision in reality) | — | No collision; barge, facility and ship undamaged |
The cue appears within ≈ 2 s of the wrong-way movement—about eight seconds earlier than it was detected by eye, giving ample time to correct.
4 | Safety margin gained
- Early detection: error flagged while the ship was still > 1 ship-length from the barge berth.
- Course preservation: prompt correction keeps the track inside the 500-ft channel, clearing the facility by ≈ 40 m.
- Cost avoidance: prevents US $21 m damage and weeks of repair downtime.
Take-home message
A mis-executed helm order—not equipment failure—drove Yochow into OSG Independence-243. Helm Order Monitor’s single WRONG HELM banner, reinforced by a short sound signal, would have surfaced that mistake in seconds, giving the bridge team the clear prompt needed to correct the wheel and finish the turn safely.
