Super Flat Speed Sails

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Daniel Hearn:
Thanks, all, for the input on super flat speed sails.  Although I'm a lightweight, Kent nailed my thinking exactly.  Since I'm limited to two sail options for a ranked regatta, what are the odds that I'd select a super flat for one of the two? For a regional regatta over a weekend, maybe.  For a national regatta over a week, not likely. 

Looking forward to seeing you all on the ice!

Daniel
team maDisoN
US 5352

eric_anderson:
My take on the 2 sail vs 3 is as follows:
We race in the range of 5-25 mph and the power available to an iceboat is proportional to the cube of the wind velocity V3.   So on the upper limit, you have 125 times more power available then at the lower limit.
Air friction is related to velocity squared V2  so it varies by a factor of 25 based on wind speed.
Ice to blade friction ranges at least 10 fold ( think  fresh hard black  ice to ice with an 1 ½” of stiff snow).

So we see conditions that range from low drag low power, to high drag high power and every combination and permutation in between.
So it seems to me that the fuller the sail at any given windspeed, the greater the power and drag. At some point the boat has all the power it can handle without tipping over and all the additional power is lost anyway so the best bet is to minimize drag ie get flatter(and smaller)
It is hard to imagine any 2 sails handling a 10X difference in surface drag, and a 25X difference in air friction and a 125X difference in Power available that we experience racing over this whole range without compromise.
Practically speaking, 3 sails seem to cover the range reasonably well without being too burdensome to carry.  The reality is that without a super flat sail you are not going to do well in heavy air. I would go as far as to say the super flat sail changed my whole attitude to heavy air iceboating
It is pretty rare that we go from one extreme- high wind clean ice to sticky ice in low wind in a regatta, but it happens.
Personally, I consider the ABSS to be my standard all around sail. I weigh about 170lbs.   From the baseline, I can go flatter or fuller depending on conditions.    My first decision is based on ice conditions.  Clear fast ice, I will probably use the ABSS or MS1 depending on windspeed (maybe the f01 if it is very light).
Sticky ice or with big snow drifts, I will use F01 until it is really windy. Power and acceleration are more important than top end in those conditions.
My basic  formula is something like this: take the wind speed in MPH. Add 3 if it is clear fast ice, and subtract 5 if it is sticky ice subtract 3 if there are snow drifts.
Less than10 = F01  10-18= ABSS  18+ = MS1


Cheers,
Eric

Bob Gray:
If you only have an FO1 and an ABSS, in heavy winds on clean ice , would stiffer batters in the top and possibly second from the top pocket he be much of a help?Along the same line, would putting the halyard more forward and opening the leech help?http://l.facebook.com/l.php?u=http%3A%2F%2Fwww.duluthtrading.com%2Fstore%2Fmens-home.aspx%3Fsrc%3DFBMNNC&h=PAQE173LmAQHF7ztujaUZVRfLksI4hMpZyVS1IEUczOBWxA&enc=AZMKy3t1f_vqr_dOmkoV46c36iGQynGKuDQ6VmxOf14hcOggatgdADLJ-ABw1OILOXLCp39m_CiswrUjzqrD9A9iOkHIDPbSGz43Aoiv4z4SFVDu3C7URxEYtuorVpZkptJyKteHgKA7OHQFYafR0_ljKloP1zneMaJN1MQnsWXmIMxk8tINovCm5nI6FAXB85o-RS-fYJwgJbQSGF3wfAs-72AkhQlxfII01HQDHhCSWK42-UARmpTvJEoy4fQEsDlwJV2PwbIJYZpzb4XJtCVQ0husrKRGqSwtQmXnJO8zITtX2hK0ySfqWGmomq_DorzfCkEX0LECt4fxCwaJ-hlcAGRyt0_JEysfKjepTAkdMscHcp9t_UECvpPMXcpRun3ikGX5rjGhdBtmepoAq9fhuDGtqVVU6BMtmrXGkRIDaIhewYLVx-im3zB02s61bo2DAHEjjb8T4Ov5iBFf7Gowd5aJQ71mjfXq3T7i-fdUVsDENUDBr5ggLPs08cWWUdRkm-WxZ7FKZqZHWU9X2YDntQKiIIKpHpsswyc9AEEOKEx-TvYuMr9aSwnpEg8qZumxyhbROFvmF9pEiu57iBCmjzF22SWf2gisG9-hHel3O9TykJ7fYnJk1oQXqHx-olNSGGQ7j7OLZCm2hTNzZeZsxEdR3s-NAU30fUehwlgo68PV3nvfRKPOSjNimZK2o3r-446m52r8nk0uG1KYAH4K9sxk4-6Z-mA0bj5oQnBjtFeApU1dCm-FG-5dWC4pIjHXZuMBODUFd5piC-f21vI4wbNvX2_7rYmRBenQoRg-F4T16TwX-vAVA3woCuijYalXFbHfJoFzl9NVwZW0I_JPYhfGXRk6O5gtk9hh-ipEOuWwpwTUwT34mt4E7LpHN9KOew2ExfrkJ6w9yx8rkybQ1Bxdwi03p-ml85g2_gcLhozhg0KVrsVULszM7yuJSNI4lggHz_BkVbAAsLVse3xIXSCnxkQSnFo5Cf3UyMSpi0pQuydKEPXNxr5JJAarMk6X6qYn35WncNLYqwmJOKd8h95rTSuTVlFjzLaCla5bEDP0RFY1PGgm2pjVFZISjdx-iJHDculhdCEtXDbsx3MefDCV5kzDMxA9aR13PLxsOb8T7ot4O_Y24rtHeq8h4AEok7GzmHOCFO3fQaYR-fU2i0A_CgNUZIhtFe6QuqtHc3kh9lmePDIbO7oxt2NqvHgoUvt-sVvyqKV4dx6_aHW8C2yxtKEPn9cBh8-6AO8I_JsoRtWA_btb_pLZVh3T0LKc3jRNsT8bvw9ksAOwBrVpPL7kvUPhdYF5S7XE0f42VCxsCGbRBU-C71bVAaQUDaLWSvHFfg0T7grSJkd-OAsOxO4XevNnwqh_Gsu-Ju4_g_kJQac9WrrS2zkXWoEEG5GlYyo7ubx_j4cK1_WKPtLXtgBrmFozypkBRvhxXZstN66ThOXvSXLAYZegGT2XRt3HMME1_b3VrwEbq8MLh1HVcm3cGIKEPyvJz1prleZT25qYCD3zYHoNjF6m8QKkrUYLK3GJ4AJqENwt7yKf6Sp9x1mLhzncrOT__St7xyOwiNvGfsjZGIqGDKxr8EQnnJ-T-DEGRwOV0VqqWzVNeDLRvuZnSUSQN9Hc6oDisJ3_mMGCgJTWg61iFyKqMkITxqlCwA7Krsw2eAsgb8ztCxEfkWlXaUyvgJBurzQ00CvWOsGfBjfUsTggtHyByt46oNXQjd5ESaPVBwdqtyZl6jKD84nnx9RYzNrGH9qwMBr2NlEA8JuQdcUNo__pDhRPWJio_QpYi-G89f18FGhfVORewjKsxC2uLudynQOnbPSGfMKDkU9vgrmQqLbEuEO8_evzrA8-FQtw3KIOOACEHIxyANjZ39TSMoVtuRo0b1SPPo10g1Td7qZyHwA9jDxvS3HV_rPrna7rwVW5zbCs4QGT6wtGpUOtSMs6pxc9v5GtfSNlME-xd_Nv4E4fATl22BvL-mkx5be545dP3nLh1hAgpNbBpegWLL5ACDly5UFEJb7x54K29xv4RLMDWl2taLdAa8aOZeb6gvuT0qAWBk44-uzkqnQb--u-lFY-QDHWmA1VXn2QPm-1V5goT32ZwHwAALsbfWtDI-zwPzFqjuUTEdvTQb--FEOH12FjeFbBpQwTYSCDXC9WphlAKwSXk7OqfwFP5y-QlRXOwkfKJ0t3t9Krd1SwQ5X8GB0M7nwIvil-yTwKkDl6sgcuzW1RVdvMEJ_E8eECV9lRT30jfkK3uXTOLXtoNvHF1MNOg66QijUlkxNtuW0yuxbl1mf1b6GFgh7vZy-paDcQzgho3NDIWjhJpf7fHPamjsIuKFd-bJ5MCnWNBtALK625-NhYgjx2GW_PzU2JGCT8sMu0nAP3Wl3w78xXmfkj4nQHR0eGAKu9dqg2tvzAsMGKvE-p_bN9MPEYXazu1BmMCcVBtH8ZAGuKwvYQMvMEUDXPHxaU_5OyGqhP5DtJEM5j69jNlKnm1AC7byrHgnbXljw-RC81zRe-oWw3_1YaGgUtEVBk0t5gulgpVz0xq0UnaqHkOKCqjZnbosEiDRONg8BxkD6HUaqDO2PI84OV8zWFW-F9iuDEytRxIh6ngP0uBbHBbWRKORZ79D-uC8eoc9rPUNsRFTNNnI3r__WgcWDazZRAgyDnteF108j2l8Lqv6PY5vig6Bm27XX0KP25Uq3FZ53o76DFZuJaPNuzNOGABSKG247Sknt-CeZWsvjyT2XgHAsFfKuEkBOtw7IqEvp32bKO_ZRItb0Nahvli9x1Tj8i5KxfqTVzDZiMw0trGAmNqXS-fmu_uPnCI8rI6YbeLrI6v0g_p-HR5P0FeG2p05pWYeFkAP6AFCp2ETdF-PaTJDYapVkkPq-kc32Dj1pfjKbCp0MNyJ-vPPvzUZ3MUOZcCVvwfCfYpl6bVfpptyNYkmks7keA8CPrwUdjDPEz-Vk6XQgbyYgwFviA42GoBn3Ts_XP5Boo37mHVDF4uxkqD-gIc3ETjJL_HSsoIe-unolD6DRwEVT8W9hZxogXmxZgoeIPDsiJ33iJjI5I6sQXd0CE0c8iAwLf-LzvPobs1Ktm7e_AmAxTXWK55lHPDnAJPInEBLHYe71wN6e06unPWNs_Oi9h5VSlcDpj4eOs3eT7x6GFu2ZPlA77INX20Ex5NswLd1EIOyA8QJWDWP1aGRRAUn8mT7dKwBO4XokfutwJTAaRoa7f2_lncRJPNFP6fSvd4tWiGefisD_Pms-n3fcT6UsVefSbP9MJCr1tB38tOMccyC_4eiiLmSzQhzEPwQUivXZWybTU9VHvgeJzANKK9kDfVZ1ETM7MUJAo4LFioBxjQ8bE2Fa0jsEkk1--l3sEkE-vYeGI9DSR79upHzE2y4NN6La4_RptcbDADoiafioqVTUKMy6sJUIDb8ZpMCnhNMg9tMD2LL90WTnS-EF2DYw09SF4_N--Y2DBWNDB335PefFJumyKco5jDQ08hvIVf-YG1kkg9l8RkmFzWiMBeyseAPyyjgHRAk8gsHFEwGwvv2GDKE13OUk66Zrb0RazUD4MdeUHCNBDVcitlFWYqp_UVhMXC61204flTGuVqisO5pbeZZTuQ9V7NAT_EPtE4mFB34ar0TT7b5p_rMZrZZzDYSim9yC6ePOtJR6VdzOecm8c4-KjYz8zvaOVsiPjtEFL1R9XzeI3Dh1O9G8t5vAWXLXECiInnFT9WL_YLegZhA_MIx7OYHzGWgV2ssXbzt44X0_BvIDJkpo_MezDbuwYdAhcYd_gQnCmn5F-CNfnyYyzBpDVZdlotDDLSpWMr_iRNIE71aB7lWPrnZzHYWaIZB6fjQ8tId_hCeFoTh0ZXAS-tU4Hy01pscsrHfFx-f39ql35xRpW0sTtrxARoysPcSifthYjWpsrWLDE2XDB6oOtJwl4PShsm1pC167XgJybHJjgJ-nvXTVtGI5X76xDbALNvP4WwBwBM7Pr5dQeLAW3p-YviOPF_4H7v5gmEAu79KjOvkO2LmlknVw08_QqsJJr6NGVU6J_104uJfcxWvq3dokc9YzBsKoNpD-MG59vjTe7n_IDBVHUUjj9EIQd0xOI6f_4JdAVw2Vlm1yKvKCnRnFT5MqWP6F3xFU0Nk-ovrcyzkql6R9ZAfTguqC7UAuhOx6tRHqqVmgRz6ODSVgts33LMm7z_Rojs8-VfUQel7yrM2Q0ct3xipD4oKW9M2dKCpU2tNWq0-_5-WWYbH3IS1wQGjw552h0h1Jk9o8E3B-UY5Bx_9ZYNYn_MBbQVBaJs39tTZwYk-KORkJ-hxrYP7HSU6a25bZYx5tqmj4MFZIpqkp3YcrByDrb11s7yGAt5DdtQGZ1w4L9fGc2OzDH7HwHdNPlCzsX8h9TSit046kvp6VtRMpi3OUM-u_NmVZwtZyz_2jWCuB8RqTvhQS2yUVykG5Mav1xZAMugxMnrKBHqOaw-GvU0OjNkSEguC-7UU3u6RL_RtMfgYuMw5W9l3a8lFO4X7mjqafM_0rR3K4mnOmj3BJiJ1LRnMc-HazZemEJuqaYqGE8pZIz616eL_xtQbRQr4aZZr13TnBbmvyAVhTag5ImaCHPX81WuVHdGsRt-_ne4OwUTVE88b0s5lPEUXjqMtpv3SoHkhbikpGEhb-brBiZMg2uf_6ec37CrD-XL5v_MQXZzSeJbtPJDk_vSlc63Rv3WOIRdzkrfzIrbdMeDBJ1j7CcKsWG1dh-KMxsY49r6XVW6NHC2m7HznzqpNOFCtimwPPXDQdq9Afjf5txJyQ2VJ2l7KCJFOtB9tKFqGJ1ONX3VuonZ6LCYB3z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:)

Bob Gray:
Sorry for all the mess at the bottom, somehow I hit the wrong button.

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