posted 06-15-2003 12:45 PM ET (US)        

In its report, the National Transportation Safety Board has included several photographs of the Boston Whaler 24-foot hull after the collision. These may be of interest to readers of continuousWave. A hyperlink to the NTSB report is provided below.

The NTSB report provides many details of the collision and in general is interesting reading material for mariners.

Inasmuch as the collision occurred at night, I found it interesting to note that the federally required navigation lights on both the Coast Guard boat and the other boat were not in compliance with regulations.

In the case of the Coast Guard boat, the location of the red and green side lights had been moved to the T-Top from the original location as installed by Boston Whaler, probably on the forward gunwales of the boat.

The white all-around light had also been moved to the top of the T-Top and installed on a 1-foot extension. Presumably this modification was also performed after the boat was delivered to the Coast Guard by Boston Whaler.

These moves reduced the vertical separation between the boat's white all-around light and its side lights to less than the specified distance. The separation was "about one foot", a violation of the required minimum of 3.3 feet for a vessel of this size.

To make matters more interesting, the visibility of the white all-around light on the Coast Guard boat was blocked by the presence of a radar antenna which was mounted forward of the light on the T-Top. The radome blocked visibility of the white all-around light to vessels approaching from about 10-degrees on either side of dead ahead.

On the other boat involved, the navigation lights were also found to not be in compliance with the regulations. The required vertical separation of the masthead light above the gunwales was insufficient. The arc of visibility of the sidelights was too great by about 30-degrees. The stern light was actually an all-around light fixture which had been modified by application of duck tape to limit its arc of visibility.

The other boat was subject to Coast Guard inspection and had been inspected and found to be in compliance approximately six months earlier.

A second area of interest was the operation of the engine cut-off switch ("kill switch"). The kill switch failed to shut off the engines after the helmsman and crew of the Coast Guard boat had been ejected.

According to the NTSB, the design of the circuit providing the kill switch function required that the kill switch provide a contact closure to the engine in order to shut off the ignition of the engines. One might think that in a failsafe device like this, it would be better to require the kill switch to maintain a closed circuit to enable engine operation, and use a opening of the circuit to prevent operation.

In the case of this accident, the entire helm console of the Coast Guard boat was detached from the deck and ejected overboard, yet the engines continued to operate at full throttle. The circuit to the kill switch was found to have become disconnected, thus preventing it from affecting the engine operation. If the kill switch circuit was designed for the opposite action, loss of continuity through the circuit would have stopped the engines.

I thought that it was particularly ironic that neither boat was in compliance with the required display of navigation lights, yet one was operated by the agency responsible for enforcing the regulations and the other had passed a recent inspection by that agency and found to have been in compliance. This was not the Coast Guard's finest hour.

It strikes me also as ironic that the kill switch circuit could tolerate being ripped right out of the boat and not affect the engine operation. Clearly the design was not failsafe in nature.

NTSB Report:

posted 06-18-2003 03:05 PM ET (US)            

There are some portions where you can only imagine how much worse it was than official language indicates.

My favorite is where the CG crew made an "unplanned departure" from their vessel. It makes it sound like like they decided to wander off for a break, rather than being violently ejected with such force as to rip off the console and break the stainless steel wheel.

posted 06-26-2003 05:17 PM ET (US)            

phatwhaler out.

posted 06-26-2003 05:20 PM ET (US)            

1. I would have hated to be the CO of that CG detatchment. What a huge headache and probably a whack on the career ladder.

2. I would have hated to be the two Coasties that had to go back and face said officer of #1. It is going to be a long time before those two get anywhere near a boat.

posted 06-27-2003 11:11 AM ET (US)            

It's been a while since I did this work, but that is what I remembered.

As an engineer in the manufacturing sector, this would not be the way I would have a fail safe circuit. I would have the contact closed at all time, keeping voltage on the safety indicator, and have it drop out in an emergency setting. However, there are probably other issues with engine management and safety that I am not considering.

posted 06-27-2003 04:08 PM ET (US)            

We'd pull start them with the rope and it would run just fine without any input from the key.

If we connected them up and it stalled them the problem was in the harness somewhere. If it kept running we'd kill it with the key.

Sometimes we had to put a rag over the carbs or air intake to stop the engines though if the key wasn't working right.

I could see why the engines kept running if the helm was torn away.

The power goes from the battery to the engine (through the stater wire) and then to the harness to head up front.
The key simply grounds the power pack (I think) to kill the motors.