"K. Smith" wrote in message
...
Eisboch wrote:
"Short Wave Sportfishing" wrote in message
...

On Wed, 15 Dec 2004 17:02:27 -0500, "Eisboch"
wrote:


So, what happens when you hit a rock or log at 25 knots with an Alpha
or
Bravo drive?

I don't think it falls off as this one is designed to do.

Later,

Tom


I don't know. I've never had the experience, but assume a 15,000 lb
boat
doing 25 knots and it hits an unmovable obstruction like a rock ...
lemmie
see, energy = mass x velocity squared ... seems to my intuitive
analysis,
something's going to give.

Eisboch


They get damaged the leg/gearcase part mostly badly damaged, but the
leg raises up & usually doesn't rip the transom out of the boat.

The hydraulic rams are designed to allow the stern drive to come up if
there's enough "sudden" force applied. The rams have twin walls &
compound pistons so they can sorta suck a momentary vacuum allowing the
drive to come up. The Volvo ones are similar & older ones had a
mechanical release.


K

Makes sense. Nice to know they are designed to "give". I can visualize
the leg kicking back which would allow it to provide lift up and over the
object as an inclined plane, so to speak.

Eisboch