Scott if you can find it great. Cummins QSB 6.7. 480 hp
Adding to the confusion:
Plan on your REVERSE thrust to be roughly 1/3 of FORWARD thrust.
Here are the numbers (measured with strain gauge) for my 40 HP engine:
Scott
Thanks so much for the info. Your my new hero, drinks are on me in Ft. Pierce even if you hang out with the ladies.
I seem to remember I back down and raise the RPMs to about 1200 on each engine. I'll try boosting it to 1500 next time I'm out. The information is much appreciated.
Thanks, I owe you.
I must say I've gleaned a lot of good info from this forum
OK, that's direct thrust. Now figure in the resistance of the flat transom and the angle of the rode to the anchor.
Wow, guys this is getting confusing. I never had this info I'm amazed I only drug my anchor once in 40 years.
Ha! More variables to keep the discussion going.......
The "flat transom" comment reminds me of a relevant event from a couple years ago.
Prior to entering my marina on a particularly windy afternoon (38 kt. gust 45. NOAA), I needed to confirm whether or not reverse power could stop/hold the boat against the wind with the bow pointed directly downwind.
I tested this, moments after this picture was taken, in the open bay. The answer was: yes. The engine (in reverse) could stop the boat (GPS confirmed).
It was my impression that the 3 foot chop slapping into the flat transom was of little consequence. Rather, the force was predominantly windage.
I think we can infer that for Panope, full power reverse is equal to about 40 knots of wind. Of course any surges, veering, or snatches while anchored would increase the load to some higher value.
Next time you all are out in some wind, do the test yourselves. My guess is the higher powered boats will hold themselves, in reverse, against similar wind with not much more than idle power.
Steve
At time of this photo, I was progressing under storm jib only:
.......... I was really trying to find out a proper reverse speed to maximize the setting of the anchor........... .
Peter B
Your probably correct but I need something to worry about. Not sure about the tea comment. ? Sometimes in the pursuit of knowledge we make problem where non existed. I was really trying to find out a proper reverse speed to maximize the setting of the anchor. Scott was nice enough to do the work and his answer was damn close to what I do. Lucky I guess.
Thanks.
One of the TF regulars (I can't recall who) described a technique some time last year that I thought was good.
He would set with just idle power, then shut down and have a beer, eat dinner or whatever for about an hour. This allowed the anchor soak. He then would go back and set the anchor with more force.
To me this made a lot of sense if you are in a situation where you have some force on the rode for that hour. It allows the anchor to dig in over time with mild force, then you set it deeper with the engine.