Marine Board of Investigation hears testimony in Boston

BOSTON – The Coast Guard and National Transportation Marine Board of Investigation re-convened the Alaska Ranger investigation here at the J.F. Williams Bldg. today.

This is the fourth convening of the board, whose purpose is to determine the cause of the sinking of the Alaska Ranger, and to make recommendations for preventing future maritime disasters.

Two witnesses testified at the hearing, which was open to the public.

The first witness, Herbert Roeser, owner of Trans Marine Propulsion Systems in Seattle, testified of his company’s relationship with the Alaska Ranger.

The following is a synopsis of Roeser’s testimony:

The Fishing Company of Alaska owns the Alaska Ranger, and Trans Marine Propulsion has been working with them since 1987. The Alaska Ranger came to Seattle from Singapore where she was originally a supply vessel. Trans Marine Propulsion was involved with machinery design and engine room layout on the Alaska Ranger, and had nothing to do with the structural modifications. For example, Trans Marine Propulsion installed shaft generators and rebuilt and upgraded the main engines.

He was in Spokane, Wash. when he got a call that the Alaska Ranger was in trouble. He asked where the water was coming in and was told the steering flat. He attempted to call the ship to talk with the Captain, but the Captain was very busy and was not able to speak with Mr. Roeser.

Mr. Roeser wanted to know how the water was coming into the steering compartment because of its double hull, and was surprised that water would be coming in there. He thought the water was coming through the rudder bearing.

The owners had the vessel retrofit with a double hull in the aft end of the ship because of damage to other vessels due to the trawl doors. Sometimes the heavy trawl doors damaged to the hull while hauling back the nets.

Roeser went on to talk about the Central Pitch Propeller System, which was one of the main topics of today’s hearing.

The vessel had a Central Pitch Propeller System when Fishing Company of Alaska purchased the Alaska Ranger. Initially when the vessel was first purchused the Central Pitch Propeller System had been overhauled by Bird Johnson Company. The ship was modified in 1992 to make it more fuel efficient. The modifications included kort nozzles and new propeller blades that helped in lowering fuel consumption. At the time of purchase, the ship was using a pneumatic control system; it was replaced by an electrical control system. The new system was reliable and still in use when the vessel sank.

Mr. Roeser stated that when the Central Pitch Propeller System lost hydraulic pressure, the blades would automatically go astern. He saw this happen on the Alaska Ranger’s sea trials, when the loss of hydraulic pressure was tested.

Mr. Roeser stated “This vessel was a very safe vessel. The Alaska Ranger was by far the best vessel we had in the fleet. We had very little problems with her.”

The second witness to testify was Thomas Quinn of Rolls Royce Naval Marine Company. Quinn is the product manager for the Central Pitch Propeller System. He is responsible for all Central Pitch Propeller System product and assist with its servicing.

The following is a synopsis of Mr. Quinn’s testimony:

He had never been on the Alaska Ranger, but was very familiar with the type of Central Pitch Propeller System installed onboard. Mr. Quinn provided diagrams and explained in detail how Central Pitch Propeller System systems work. The Central Pitch Propeller System on the Alaska Ranger was a very common system from its era. There may be 50-100 other vessels still using the same system.

On the Alaska Ranger, the original control box was provided by Bird Johnson and was a pneumatic control system. He explained that while the system was designed to fail “as is”, meaning the control box would hold the last command that was sent, the propellers would go astern as air pressure bled down or if another pitch command was applied.

When asked about possible scenarios he stated there were many different ones for how this system could have failed.

When asked his opinion by the Marine Board of Investigation on what happened, Quinn said, if a vessel is going full ahead and there’s flooding in the engine room, and then the vessel is going astern in my mind I think the control system may have shorted out. The electrical system may have shorted out because the boat was taking on water.

The Marine Board of Investigation will meet again here Friday morning at 10 a.m. to hear testimony from one additional witness. The Marine Board of Investigation will then tour the Rolls Royce Central Pitch Propeller System facility to more fully understand how that system works.

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