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1 of 1- Wheels
- Admiral
Offline - Registered: 1/04/2016
- Posts: 36
Fleet Opt Runs vs. Single Boat
I am getting different results on the ref boat with the same polar between a fleet run and a single boat opt run. This happens with both grid and iso runs. All conditions are the same. I have two marks – Newport and Bermuda. I have manually located all the boats at the Newport mark with the same start time. Both runs show the same start point and time/date and polar file, but they have slightly different routes and ETE difference of about 42 minutes. What am I not seeing here?
- Nick
- Moderator
Offline
- Registered: 9/16/2015
- Posts: 3,386
Re: Fleet Opt Runs vs. Single Boat
It could be polar scaling?
- Wheels
- Admiral
Offline
- Registered: 1/04/2016
- Posts: 36
Re: Fleet Opt Runs vs. Single Boat
I did have 95% in for night and some wave limits. I have made all of those 100% and it has gotten closer but they are is still 17 minutes apart.
- •
Thread Starter- Hats
- Admiral
Offline
- Registered: 6/04/2021
- Posts: 23
Re: Fleet Opt Runs vs. Single Boat
Wheels, I'm working on the Newport to Bermuda race also. Ran into the same exact issue as you. I found two issues, the first one I fixed, the second one is still confusing:
1. Double check the Optimal Routing Solutions for each boat and make sure the Lat/Lon starting points are identical. Somehow mine were different.
2. When comparing the two Optimal Routing Solutions, about the third hour in, the one solution has a TWA of 152 and BSP of 7.3. The second solution has a TWA of (152) (Jibing) and a BSP of 8.2kts. The routes start to differ from there.
I agree with you, these routings should theoretically be identical right? Please post if you find a solution, thanks!
- Wheels
- Admiral
Offline
- Registered: 1/04/2016
- Posts: 36
Re: Fleet Opt Runs vs. Single Boat
I am also seeing problems in the first few data points of the opt routes. Some show going out of 9nm in the correct direction but the Lat Long is still at the starting point. Another one goes out and then on the third data point it is back at the starting Lat/Long. I suspect this is an issue with manually entering the boats/positions/times vs.getting that info from Yellow Brick during an actual race.
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