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Guests & Members Post & Read => Open Forum => Topic started by: Daniel Hearn on November 10, 2015, 05:08:37 PM



Title: Super Flat Speed Sails
Post by: Daniel Hearn on November 10, 2015, 05:08:37 PM
Interested to know how many of you have a super flat speed sail (North/Ullman MS-1 or the like) in your quiver?  Have you had much occasion to use it? Enough to justify the expense versus other places you could spend your ice sailing dollars? Have you experienced circumstances where most everyone else was overpowered with standard speed sails, but you were crazy fast and in control with your super flat? If you were a lightweight sailor (145 lbs.) would it change your perspective?   


Title: Re: Super Flat Speed Sails
Post by: Bob Rast DN1313 on November 11, 2015, 08:15:52 AM
I have a older 1 D speed sail seems to work best in heavy air clean ice
It is a little shorter at luff end cut a little smaller than a F01 with less draft

Prefer to only use in 15 to 20 mph clean ice
Easy to stall in lighter conditions
The sail is biggest drag so flatter and less area should give extra speed in certain
Conditions
I like to keep it simple only 2 sails in my Quiver
Bob Rast
DN1313


Title: Re: Super Flat Speed Sails
Post by: wnethercote on November 12, 2015, 03:12:38 PM
I have an MS-1 which I have used mostly for knocking about when it isn't quite windy enough for my storm sail.  The attached photo is of it in use on a windy day on Mush-a-mush (yes - that is the name of the lake ...).  It is a great heavy air cruising sail.

My racing experience is mixed.  I used it after I found myself overpowered with an ABSS in the first race of last year's New England championships, but I went slower around the course with the MS-1 than with the ABSS because of problems on the downwind legs.  It was more controllable than the ABSS in the heavy conditions, but with the flatter entry, on about half of my gybes I stalled the sail and it was difficult to reattach the flow.  With more experience I might do better on the gybes (maybe just sail hotter angles in and out of the gybes: I tend to sail too deep) and do better overall.  I know that Eric Anderson used an MS-1 too on that day and his results were much better (but they always are   :-)  ).

(Edit:  I have won races with it in club racing when I seemed to do a better job of keeping the flow attached after gybes - and truth be told, the competition wasn't as hot as at the New Englands)


Title: Re: Super Flat Speed Sails
Post by: eric_anderson on November 14, 2015, 08:48:19 PM
I have owned a 1D f speed and a MS1.  They are essential tools when the wind is up.  They are hard to accelerate, but have higher top end upwind and downwind when the ice is clean and speeds are high.  The lighter you are the flatter the sails that you can use in a given wind speed.

Cheers,
Eric


Title: Re: Super Flat Speed Sails
Post by: KB [us5219] on November 17, 2015, 05:51:48 PM
I have an MR-1 (even flatter than an MS-1).  I don't use it often, but when I do...  I am in a mindset where I know I need to sail agrresive angles for more acceleration.  I have found that it can be very fast-and not sure how much of that is the sail and how much of it is my greed for speed mindset with that sail.
I would love to buy an MS-1 (or trade my MR-1 with someone who is lighter than I.  But here is a problem--- we are allowed 2 sails in a ranked regatta.  Use your MR-1 on the first day, and now you have to choose from only one of your other two(full or speed) for the rest of the regatta.



Title: Re: Super Flat Speed Sails
Post by: Daniel Hearn on November 18, 2015, 11:52:57 AM
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


Title: Re: Super Flat Speed Sails
Post by: eric_anderson on November 21, 2015, 03:23:35 PM
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


Title: Re: Super Flat Speed Sails
Post by: Bob Gray on November 22, 2015, 08:11:07 AM
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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:)


Title: Re: Super Flat Speed Sails
Post by: Bob Gray on November 22, 2015, 08:14:19 AM
Sorry for all the mess at the bottom, somehow I hit the wrong button.