Operator1 had entered the Chittenden/Ballard lock in his 41' Carver cabin motorboat.  The lock attendant directed him to tie on the starboard side of the most forward portion of the lock.  Operator1 secured two lines with the attendant's help to the concrete wall.  Four fenders were in placed on both sides of the boat.  Operator1 has had previous experience transiting the locks. 

Several large boat then secured to the wall, a smaller sailboat was then directed to raft to the port side of Operator1' boat.  As the sailboat was approaching Operator1' boat a bow line was thrown to Operator1' boat and held while waiting for the sailboat to move forward enough to throw a stern line.  While trying to drive the sailboat and use a pole to extend the stern line, the stern of the sailboat drifted away from port, making it impossible to secure his stern.  The sailboat then drifted perpendicular to Operator1' boat.  There were no other boats behind Operator1.  A crew member of the sailboat asked Operator1 to release the bow line and they would then reposition the boat.  

The sailboat then went into reverse and struck the opposite concrete wall with its stern.  Then the sailboat overcorrected and headed forward under power towards Operator1' boat.  With a crew member at the bow of the sailboat and Operator1 on his boat trying to fend off and insisted the sailboat go in reverse, his bow struck the larger vessel with the anchor at the lower port forward salon window.  The accident punctured and shattered the window with slight damage to the surrounding port side.

There were no injuries.

Seattle                       