Classification
- Incident Type: Allision
- Severity: Medium
- Investigation body: National Transportation Safety Board
Vessel Details
| Field | Value |
|---|---|
| Vessel Name | Riverside |
| Vessel Type | Tanker |
| Flag State | Malta [MT] |
| IMO Number | 9412464 |
| Gross Tonnage | 62856 |
| LOA (m) | 249.9 |
| Breadth (m) | 44.0 |
| Owner/Operator | Glory Riverside Navigation LTD / Thome Ship Management PTE LTD |
| Year Built | 2009 |
| Engine | 1 x 13,560 kW STX MAN B&W 6S60MC-C diesel engine |
| Crew Size | 21 crew and 2 pilots |
Incident Details
| Field | Value |
|---|---|
| Date | 2021-03-15 |
| Time | 13:02 CDT |
| Location | Corpus Christi Channel, Ingleside, Texas |
| Coordinates | 27.8186, -97.2088 |
| Region | United States |
| Fatalities | |
| Injuries | 0 |
| Missing | |
| Persons on Board | 23 |
| Pollution | None reported |
| Direct Damage | USD 7.55 million |
| Economic Damage |
Key facts
- At about 13:02 CDT, the loaded tanker lost propulsion and its port bow struck the dock's mooring dolphin and catwalk at about 5 knots.
- Riverside carried 717,554 barrels of crude oil and was bound for Lisbon, Portugal.
- Tug Honor pushed the port bow, then joined tugs Strength, America, and Courageous in stopping the vessel about 1,600 feet beyond the dock.
- The NTSB estimated damage at USD 550,000 to Riverside and USD 7 million to the facility. No injuries or pollution were reported.
- The NTSB identified an unresolved main-engine start problem and fouling of the No. 6 air-start actuator valve as central to the casualty.
Narrative
On March 15, 2021, two Aransas-Corpus Christi pilots boarded Riverside at 10:18 CDT to assist with its departure from the Port of Corpus Christi. The tanker left the EPIC Marine Terminal at 10:54 with two tug escorts, carrying 717,554 barrels of crude oil for Lisbon. After Riverside passed the Harbor Bridge at noon, the escort tugs departed and the vessel continued outbound in the Corpus Christi Ship Channel.
The pilots slowed Riverside to allow the tanker Nordic Aquarius to leave the Moda Ingleside Energy Center No. 4 dock ahead of it. At 12:55, Riverside was making about 8 knots when the pilot ordered the engines stopped. As the vessel slowed, it sheered to port. A hard-starboard rudder order did not correct the heading, so the pilot ordered dead slow ahead to increase water flow over the rudder. The main engine failed to restart from the bridge and again from the engine control room. Tug Honor pushed on the port bow, but moved clear to avoid being trapped between the ship and dock. A local attempt to start the engine astern also failed. The crew and pilots considered using the starboard anchor but rejected that option because of the vessel's speed and shallow water near the dock.
At 13:02, Riverside's port bow struck the No. 4 dock's mooring dolphin and catwalk at about 5 knots. The vessel continued past the pier until Honor, assisted by Strength, America, and Courageous, stopped it about 1,600 feet beyond the dock and helped berth it at the adjacent Flint Hills dock. The dock and mooring dolphin sustained significant damage, including a missing catwalk section. Riverside sustained hull indents, bent internal frames, scraping, and a bent port anchor shank. The NTSB reported no injuries or pollution and estimated total property damage at USD 7.55 million.
The NTSB determined that the probable cause was the ineffective evaluation and incorrect solution of the main-engine start problem by the company and shipboard engineers. Investigators found that fouling of the No. 6 air-start actuator valve had been overlooked. The NTSB also identified moisture and insufficient routine drainage of the air-start system as contributing factors because they allowed hardened grease to build up in the actuator valve.
Sequence of events
| Date/time | Event |
|---|---|
| 2021-03-15 10:18 CDT | Two Aransas-Corpus Christi pilots boarded Riverside to assist with departure. |
| 2021-03-15 10:54 CDT | Riverside departed the EPIC Marine Terminal with two tug escorts. |
| 2021-03-15 12:00 CDT | Riverside passed the Harbor Bridge; the escort tugs departed. |
| 2021-03-15 12:45 CDT | The pilots agreed to slow Riverside to allow Nordic Aquarius to depart the Moda dock ahead. |
| 2021-03-15 12:55 CDT | The pilot ordered the engines stopped while Riverside was making about 8 knots. |
| 2021-03-15 12:58 CDT | Riverside sheered to port; the rudder order had no effect and the main engine failed to restart. |
| 2021-03-15 13:02 CDT | Riverside struck the No. 4 Moda dock's mooring dolphin and catwalk. |
| 2021-03-15 after 13:02 CDT | Four tugs stopped Riverside and assisted it to the adjacent Flint Hills dock. |
Contributing factors
| Factor | Evidence status | Description |
|---|---|---|
| Ineffective evaluation of the main-engine start problem | Confirmed finding | The NTSB found that company and shipboard engineers did not identify and correct the fouling of the No. 6 air-start actuator valve. |
| Moisture and insufficient routine drainage | Confirmed finding | The NTSB found that moisture in the air-start system and inadequate routine drainage allowed hardened grease to build up in the actuator valve. |
| Reliance on an incorrect temporary solution | Confirmed finding | The chief engineer engaged fuel-injection limit-cancel mode without identifying the underlying start-system fault; NTSB analysis states that this setting did not affect starting. |
Investigation
The National Transportation Safety Board completed Marine Investigation Report MIR-22/07, working with the U.S. Coast Guard Sector Corpus Christi. The NTSB determined the probable cause and contributing factors described above. Its lesson learned was that unresolved slow-speed diesel starting problems require timely, thorough evaluation and, when necessary, assistance from a qualified diesel technician.
References
- NTSB Marine Investigation Report MIR-22/07
- NTSB investigation page DCA21FM017
- NTSB press release on the Riverside investigation