View previous topic :: View next topic |
Author |
Message |
dllee
Joined: 03 Jul 2009 Posts: 5329 Location: East Bay
|
Posted: Tue Aug 28, 2012 2:55 pm Post subject: |
|
|
Race cars and motorcycles have fairings and wings to counter exactly that problem.
Don't Aussie18's have wings on the bow? |
|
Back to top |
|
|
mac
Joined: 07 Mar 1999 Posts: 17750 Location: Berkeley, California
|
Posted: Tue Aug 28, 2012 3:34 pm Post subject: |
|
|
John Craig (race director) argued that the 72 foot length of the hulls for next year would be long enough that the voodoo chop at Crissy would not affect them. But he also thought that the 45's would be long enough. From sailing a formula board in voodoo enough chop I know that having a wide front end slap down also causes problems. You don't fully bury the nose if you're sailing right, but a big slap will slow you down enough to throw you off the front. Let's see what adjustments they make with the 72's. |
|
Back to top |
|
|
hemmy007
Joined: 10 May 2002 Posts: 101
|
Posted: Tue Aug 28, 2012 3:42 pm Post subject: |
|
|
mac wrote: | John Craig (race director) argued that the 72 foot length of the hulls for next year would be long enough that the voodoo chop at Crissy would not affect them. But he also thought that the 45's would be long enough. |
Looking forward to seeing the photos
soon that will refute this point.
Ouch, 72's on the pitch-pole-roll ! |
|
Back to top |
|
|
89Spring
Joined: 24 Jul 2003 Posts: 241
|
Posted: Tue Aug 28, 2012 4:01 pm Post subject: |
|
|
Any type of spoiler is going to add drag and slow the boat down. The bear away through the death zone is where and when it is an issue. Any time guys or drivers or who ever is pushing the particular medium to the limit there will be crashes. F1 cars have wings to give down force do you those wings now stop the car from a yard sale? Nope it just turns into a bigger yard sale because the added down force now let's the car get to a higher speed. The reverse sheer bows are not going to stop a pitchole just let the boat get to a higher speed before pitchpole. The 45s have already flipped over a few times.
The 72s are going to be hairball. The down side to the cats is that match racing in the traditional form is not really going to happen. Imagine the dial up when entering the box and each boat is doing 30.
I watched two days of racing from the water. The best spot is at the weather gates. I think it is pretty cool. From there you can see the race course. If you don't have a boat I would go on the rocks east or west of the St.FYC. I think a table at St.FYC was 5k for the day? |
|
Back to top |
|
|
andydavis
Joined: 11 Apr 1999 Posts: 319 Location: Point Isabel
|
Posted: Tue Aug 28, 2012 4:51 pm Post subject: |
|
|
tony wrote: | The bow design is a compromise that improves speed when the boat is sailed as intended... |
Of course, you can believe whatever you wish, although I don't think there's any evidence that this bow shape does anything to improve speed.
With regards to an additional foil at the bow to provide a counter acting pitching moment, that is clearly possible; however, this is a one design, not a development class. The AC 72 is more of a development class, with the number of appendages limited. |
|
Back to top |
|
|
dllee
Joined: 03 Jul 2009 Posts: 5329 Location: East Bay
|
Posted: Tue Aug 28, 2012 6:06 pm Post subject: |
|
|
So maybe they'll come up with a quick release mainsheet, and jibsheeter.
Dump the power ASAP the bow starts to plow. Those tall masts don't lend to forgiveness, nore does the narrow noses which normally lie very close to the water at speed. |
|
Back to top |
|
|
SPQR
Joined: 18 May 2004 Posts: 274
|
Posted: Tue Aug 28, 2012 10:30 pm Post subject: |
|
|
So maybe a dumb question, I haven't followed the AC stuff, I went to Kauai instead. That said, reading through this the AC raced the AC 45's this year for practice (?) and the the real AC next summer with AC 72's? |
|
Back to top |
|
|
89Spring
Joined: 24 Jul 2003 Posts: 241
|
Posted: Wed Aug 29, 2012 12:13 am Post subject: |
|
|
Pretty much you got it. This is the AC 45 world series. I don't think it has anything to do with the Louis Vuitton series and the actual AC |
|
Back to top |
|
|
tony
Joined: 05 May 1994 Posts: 77
|
Posted: Wed Aug 29, 2012 8:30 am Post subject: |
|
|
andydavis wrote: | tony wrote: | The bow design is a compromise that improves speed when the boat is sailed as intended... |
Of course, you can believe whatever you wish, although I don't think there's any evidence that this bow shape does anything to improve speed.
|
Maybe not, but apparently you believe it too since in an earlier post you said:
andydavis wrote: | It does have a purpose, principally reducing spray drag at high speeds.
|
|
|
Back to top |
|
|
andydavis
Joined: 11 Apr 1999 Posts: 319 Location: Point Isabel
|
Posted: Wed Aug 29, 2012 10:11 am Post subject: |
|
|
tony wrote: | andydavis wrote: | tony wrote: | The bow design is a compromise that improves speed when the boat is sailed as intended... |
Of course, you can believe whatever you wish, although I don't think there's any evidence that this bow shape does anything to improve speed.
|
Maybe not, but apparently you believe it too since in an earlier post you said:
andydavis wrote: | It does have a purpose, principally reducing spray drag at high speeds.
|
|
yeah, but clearly offset by the speed loss to capsize, or throttling back to avoid it. |
|
Back to top |
|
|
|
|
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum You can attach files in this forum You can download files in this forum
|
|
|