|
|
Post by hergfest on Jun 25, 2007 22:57:46 GMT -8
This is really a Barnacle question, but I did a trip to Friday Harbor today and when the Yakima docked at Anacortes she had to make two tries for the dock. Although I missed the first part of it, she was defiantly backing up before coming back into the slip. Any reason for this? Am I going insane?
|
|
|
|
Post by EGfleet on Jun 26, 2007 6:04:41 GMT -8
This is really a Barnacle question, but I did a trip to Friday Harbor today and when the Yakima docked at Anacortes she had to make two tries for the dock. Although I missed the first part of it, she was defiantly backing up before coming back into the slip. Any reason for this? Am I going insane? Ooo! Ooo! I know this one! It's called "nasty current running in front of the Anacortes dock." Barnacle can give you the specifics on just how nasty it can get, particularly with a Super. And a telegraph Super at that!  |
|
|
|
Post by Barnacle on Jun 26, 2007 7:30:16 GMT -8
This is really a Barnacle question, but I did a trip to Friday Harbor today and when the Yakima docked at Anacortes she had to make two tries for the dock. Although I missed the first part of it, she was definitely backing up before coming back into the slip. Any reason for this? Am I going insane? I'm not going to state whether or not you're going insane based upon this one instance. ;D Seriously though... okay, class, get a beverage if you like, this might be a fairly long explanation... The way Ship (note: singular!) Harbor is shaped, after a certain point in the tide--no matter whether it's going out or coming in--a back eddy sets itself up. The later into the tide it is, the further out from the dock the back eddy. The tripping point is about three hours after low water, and three-and-a-half to four-and-a-half hours after high water. The complications start here: the magnitude of the tide doesn't always correlate to the intensity of the back eddy. I've found a 2.5 knot ebb (left-to-right) out in the channel and, about a boat length outside the first dolphins (there are three pair), the current suddenly stops and it's flatter than Saskatchewan from there to the wingwalls. Problem is, that flings the stern off toward Vancouver Island somewhere and I find myself trying to parallel park a 382-foot sled. On the other hand I've seen the tide drop two feet in five hours and, contrary to what common sense says, the current is running inside the dophins like a squirrel with its tail on fire. And, on rare occasions--usually a strong ebb--the back eddy that you've set up for and planned everything out for won't be there and it's time to back 'er out and try again. And of course, sometimes we predict incorrectly. ;D Add in the factor that the current isn't running straight across the face of the dock; sometimes it will push you away from the dock, sometimes push you toward it. The other challenge is the telegraph-throttle Super class boats. With a screw on the front and a screw on the back but only one telegraph, they don't act independently. So when we go for the astern propulsion, we lose the prop wash over the aft rudder and we can't steer with the back end of the boat. And until we're going slow enough that the prop wash is visible coming out from under the bow, we can't steer with the bow rudder either. ;D This is why it's vital to make your predictions correctly or, barring that, know you've screwed up early enough to back out into the stream and try again. I've been fortunate; in five years of playing games, I've only had to back out three times (two of them were earlier this year on a single landing, though!). However, I've also come in fast enough a couple of times that I wondered if I was going to stop in time (I did). This may be on the quiz at the end of the week; class dismissed!  |
|
|
|
Post by hergfest on Jun 26, 2007 16:56:04 GMT -8
Good explanation!
|
|
|
|
Post by zman on Jun 26, 2007 20:00:51 GMT -8
Excellent!
|
|
|
|
Post by BreannaF on Jun 26, 2007 20:45:10 GMT -8
What do you mean by just "good"? After reading that blow-by-blow of docking the ship, I feel like I just managed to hold onto the bucking bronco for the 8 seconds.....
I've read that three times now, and from the way you wrote that, I feel not only well informed, but I feel like I had a wild ride standing right there next to you!
You ought to write a book someday....... Thanks for the ride.......
|
|
