kaydano
Well-Known Member
- Messages
- 4,312
- Reaction score
- 2,222
A boat has two pivot points, one near the front of the boat when going forward, one near the back when going in reverse. The pivot point is the point at which the boat pivots in a turn. When going forward, and turning to port, the stern kicks out to starboard more than the bow turns to port. Since the outboard causes the stern to swing out more than the bow turns in, the pivot point of the boat is near the front of the boat (for example, the pivot point might be 1/3rd the distance from the front of the boat to the back). Likewise, in a reverse turn, the bow swings out more than stern, so the pivot point of the boat moves toward the stern end of the boat (lets say 1/3rd the distance from the stern).
Let's say you are at a dead stop, no wind, no current. You turn hard to port (turn the wheel as far as it goes), and you instantly accelerate to 2000 rpm. The boat travels in an arc to port. Let's say you stop exactly when the boat is facing 180 degrees from the direction you started. Now, you put it in reverse, instantly go to 2000 rpm, travel in a reverse arc until you are back to your original bearing (you're back at the zero degrees starting point).
Two questions:
1) At the end of the above maneuver, are you in the EXACT same spot as when you started?
2) If yes, does the boat travel the exact same arc in each direction (is the forward arc identical to the reverse arc)? Or are they two different arcs, but each starts/stops at the same point?
Keep in mind the pivot points...
This is not a trick question. I don't know the answer.
Let's say you are at a dead stop, no wind, no current. You turn hard to port (turn the wheel as far as it goes), and you instantly accelerate to 2000 rpm. The boat travels in an arc to port. Let's say you stop exactly when the boat is facing 180 degrees from the direction you started. Now, you put it in reverse, instantly go to 2000 rpm, travel in a reverse arc until you are back to your original bearing (you're back at the zero degrees starting point).
Two questions:
1) At the end of the above maneuver, are you in the EXACT same spot as when you started?
2) If yes, does the boat travel the exact same arc in each direction (is the forward arc identical to the reverse arc)? Or are they two different arcs, but each starts/stops at the same point?
Keep in mind the pivot points...
This is not a trick question. I don't know the answer.