Select to expand quoteMidAtlanticFoil said..
I've got my pre-order in as of yesterday and hoping for 2 weeks from now.
Is there only one HA tail ? and what size?
Select to expand quotekobo said..MidAtlanticFoil said..
I've got my pre-order in as of yesterday and hoping for 2 weeks from now.
Is there only one HA tail ? and what size?
Good questions. I'm hearing rumors of a 195. Not sure on other sizes. Would make sense.
Select to expand quoteMidAtlanticFoil said..kobo said..MidAtlanticFoil said..
I've got my pre-order in as of yesterday and hoping for 2 weeks from now.
Is there only one HA tail ? and what size?
Good questions. I'm hearing rumors of a 195. Not sure on other sizes. Would make sense.
Any "KD Maui" bull nose tips in the shape profile ??
Select to expand quotePacey said..greg87foil said..
It's pretty easy to conclude that stabilizers spend a lot of time providing upward lift. Front wings stall at around 15-20 deg depending on design, but tails are usually set at 2-3 less than that. So whenever we are at speeds close to stall speed, the tail will be angled upwards (wrt the flow). Let's say you're foiling at a low speed and the front wing is at 13 deg aoa, your tail wing will then be at 10 deg aoa. Even though the section is upside down (bc it's designed to work efficiently at higher speeds), at 10 deg aoa it will provide an upward force. You're right that downwash could reduce the "effective" aoa of the tail wing, but even if that's another 2 deg or so, you're still at 8 deg positive angle, which would mean an upward force.
It's important to consider that cambered sections typically have their angle of zero lift at negative 2-3 degrees. If you have a cambered section such as a NACA 63-412 used as both main foil and stabiliser, and you had the main foil set at 0 degrees angle of incidence and the tail set at -2, then the stabiliser would need to be rotated positively be about 5 degrees before it started to generate to positive (i.e. upward) lift. And that's not accounting for downwash, which is significant and increases with main foil AoA.
For example, if you crank a typical mid aspect (AR = 5) main foil up to 10 degrees AoA with a lift coefficient of about 1.3, the downwash will be approximately 9 degrees. The downwash angle would need to drop below 5 degrees for the stab to be generating positive lift.
These are approximate numbers based on rules of thumb for downwash (i.e. downwash angle = (35 x CL) / AR), but they are intended to illustrate that the assumptions that FoilAddict is using are not clear cut. I accept that at when getting up on foil there will be a short period where the main foil is stalled or very close to stall, and the stab may be producing positive (upward) lift, but the I think the assumption that the stab operates for extended periods generating upward lift is incorrect, and if true would bring into question the need to use a cambered section with its cambered side on the underside of the stabiliser. After all, camber is typically used to increase the available lift coefficient on the cambered side while decreasing the maximum lift coefficient available on the flatter side, and shifting the drag bucket of the foil over so that it is centred on the most commonly used lift coefficient. If FoilAddict is correct he is effectively saying that we have our stabiliser sections upside down and we would get better stall and drag performance if we switched.
NACA 63-412 lift and drag curves for reference:
The whole point of the discussion was to figure out what a potential downside could be of a higher aspect tail vs a lower aspect tail (for the same tail surface area). As a higher aspect ratio reduces the stall angle of attack, I thought it would be worthwhile exploring when these near stall situations occur. And I think even accounting for downwash, camber (making the zero lift angle negative by a few degrees) and the angle the tail is set at, we can all imagine scenarios where the tail provides positive lift and potentially close to a stall angle (slow speed).
However I fail to understand how the tail could stall BEFORE the front wing stalls? If the AR of the tail is higher than the AR of the front wing? Different sections?
Anyways, I can see how a higher aspect ratio tail would not be beneficial at low speeds, but really start to shine when going faster (more stability, less drag).
Select to expand quotegreg87foil said..
However I fail to understand how the tail could stall BEFORE the front wing stalls? If the AR of the tail is higher than the AR of the front wing? Different sections?
The foil sections are inverted relative to one another, so for example for the NACA 63-412 that I showed the lift curve for in a previous post, it stalls at about -12 degrees and +15 degrees. So if the difference in angle of incidence between the foils was zero, and there was no downwash effect, the stab could conceivably stall earlier than the main foil.
Most foils have a difference in angle of incidence between the main foil and the stab that is greater than zero, and if this was around 3 degrees, the foils would stall at about the same time.
But this is ignoring downwash, and my guess is that as soon as the flow on main foil reattached, its downwash would result in the stabiliser also unstalling. So I agree with you, I don't see how the stabiliser could stall when the main foil was not stalled unless it was very highly loaded (i.e. very small or a lot of back foot pressure in a turn).
Select to expand quotePacey said..greg87foil said..
However I fail to understand how the tail could stall BEFORE the front wing stalls? If the AR of the tail is higher than the AR of the front wing? Different sections?
The foil sections are inverted relative to one another, so for example for the NACA 63-412 that I showed the lift curve for in a previous post, it stalls at about -12 degrees and +15 degrees. So if the difference in angle of incidence between the foils was zero, and there was no downwash effect, the stab could conceivably stall earlier than the main foil.
Most foils have a difference in angle of incidence between the main foil and the stab that is greater than zero, and if this was around 3 degrees, the foils would stall at about the same time.
But this is ignoring downwash, and my guess is that as soon as the flow on main foil reattached, its downwash would result in the stabiliser also unstalling. So I agree with you, I don't see how the stabiliser could stall when the main foil was not stalled unless it was very highly loaded (i.e. very small or a lot of back foot pressure in a turn).
Im thinking it could be that in sharp turns about the pitching axis (when pumping, or heavy back foot when banked over) the radius of the circle the back wing travels is different than the radius of the circle the front wing travels on, and therefore the angles of attack of the front and back wing could be temporarily completely different? In this situation I can see how a tail could stall while the front wing isn't.
either way, definitely keen to try the HA tails when they come out! Specs (span, chord) would be cool to know
faster, more glide and more stable than V 200. More locked in. Sounds like a good winging tail to me 
Yeh true. 925 is loose as hell anyway. might be a good proning combo .. I whacked the V tail on again yesterday for a prone with a chopped 1250 (just cause) and she did pump "quicker" but the unstable wobble every now and now really messes with your pumping Rythm.
I understand the HA195 tail is out. I have one on order. ??Any early rider feedback?
Haven't tried it myself. But know two who have. Fast, loose and works well with the HA especially downwind. Opens there potential up. Loosens up the HS wings and adds speed and glide to. Pretty much what you'd expect. Need to try it myself soon.
I have been riding it for a few sessions. What I notice most is the reduced drag. Therefore the tail feels a lot faster. Haven't had the chance to test it in waves yet.
Select to expand quoteHubDekkers said..
I have been riding it for a few sessions. What I notice most is the reduced drag. Therefore the tail feels a lot faster. Haven't had the chance to test it in waves yet.
Have you had to adjust your mast position or amount of shim using the HA195 compared to your previous tail...?
The guy I spoke to yesterday (whose as good as it gets on a wing locally) didn't change mast position. Have also heard today from two others who have had the tail for a fair while now - they settled on a blue 0.5 shim just to take out any subtle drag. Even faster.
When the first guy above went out yesterday (on the 925 doing an avalon to Secret harbour run) said initially it felt like twitchy city - but dialed it in quickly and was able to go top to bottom - and as she turns so well and fast - as he came off the top the speed enabled him to connect multiple swell lines . and there was like zero swell yesterday. Now he's pretty darn good at doing that anyway so to say he did markedly better - is worth taking note.
.. oh and with reference to drag - he did notice some subtle drag on minus 1 so will try the blue next.
Select to expand quotelongboard said..HubDekkers said..
I have been riding it for a few sessions. What I notice most is the reduced drag. Therefore the tail feels a lot faster. Haven't had the chance to test it in waves yet.
Have you had to adjust your mast position or amount of shim using the HA195 compared to your previous tail...?
No, I did not change anything. Mast position is the same. Normally I ride the v200 +1 with the 50 fuse. I tested the HA195 with the HA195 +1 with the 60 fuse.
I have been riding it with the ha925 and ha725. I'll go out today to do some back to back flat water pumping to be able to compare better.
Select to expand quoteHubDekkers said..longboard said..HubDekkers said..
I have been riding it for a few sessions. What I notice most is the reduced drag. Therefore the tail feels a lot faster. Haven't had the chance to test it in waves yet.
Have you had to adjust your mast position or amount of shim using the HA195 compared to your previous tail...?
No, I did not change anything. Mast position is the same. Normally I ride the v200 +1 with the 50 fuse. I tested the HA195 with the HA195 +1 with the 60 fuse.
I have been riding it with the ha925 and ha725. I'll go out today to do some back to back flat water pumping to be able to compare better.
Sounds good - thanks for the feedback!Keep it coming!
I received my HA195 today. I might try it tomorrow but the ocean temp in northern New England is in the 40s, so maybe wait until I get to Florida in two weeks. Here's what it looks like compared to the V and 232 V1.
Select to expand quoteradair said..
I received my HA195 today. I might try it tomorrow but the ocean temp in northern New England is in the 40s, so maybe wait until I get to Florida in two weeks. Here's what it looks like compared to the V and 232 V1.
Thank you for posting this. I should have one in the next week, but there is no wind in the foreseeable forecast so it might be a bit before mine hits the water.
Gave the 925 and HA195 stab a run today (-1). Conditions were 15-25Mph with a 4M BRM, well powered up, flooding tide against the wind in a river/bay with short wind fetch setting up the odd knee high sets.
First thoughts were great until I tried to gybe and I stalled off foil (hadn't done that in ages). Started getting worried so I kept cruising up wind to meet a friend. Failed my first tack. Worried more. Seemed like the glide I was expecting wasn't there. As I felt the tail wing out more, I realized the glide was there, but I really needed to be on my game. No wishy-washy transitions allowed. Need to set your bank angle and hold and you are good.
The ride itself (not making transitions in these specific conditions) felt amazing. I've been really digging the powered up S carves lately in these sub par type conditions and this setup was amazing. Super easy to set steep bank angle with the rear ankle and power through turns. Crank a heelside turn into the wind until almost dead upwind, then send it downwind on a cranking toeside turn before re-engaging the wing and swinging it back into the wind, on repeat, utilizing the chop/swell all the while.
The end of the session offered up a mogul field of knee high runners criss-crossed with other bumps. I was brought back to my east coast (USA) snowboarding roots and ripped them apart, finding the runners and banking and slashing everywhere. Ended the session by weaving my way through the kiters mowing the lawn catching some air in the shallows with a smile on my face.
Going to try the stab at -2 next, or plus 1. Felt faster than the fv200 unchopped. Happy with it so far. With the investment over the fv200, jury is still out! The rippability seemed up another level, that's for sure. 
We had a short warm spell 4 deg c. Rode the HA195 with 1325 and 1550v2 with 70 fuse 0.5 shim Winds 12-20 knots. Found it rolls easier and seems to lock in better on jibes. Carving with the 1550 was impressive. Can't wait to get out with 1125 and 925 Need weather to warm up currently -18 c.
I am hooked
I'm hearing more good things about this tail from someone who should be listened to. On the HA as expected but also the HS - especially the 1050!!
Got mine today! (Thanks Hub) wind coming on Thursday, will report back after a session in the waves with the 925. Will start at -2 I think since that's what I've been running my fv200 on.
Select to expand quoteeppo said..
I'm hearing more good things about this tail from someone who should be listened to. On the HA as expected but also the HS - especially the 1050!!
Winging or prone ? Was thinking of selling my 1050 after getting the 725, never thought I would do that when I got it !
Paired the HA195 (no shim) with the HS1850. Sorry can't compare as both wings are new. But I got right up winging. I'm a beginner and was able to complete more flying jibes then before. I came to this set up from a Neil Pryde Glide XL setup. It's much faster and cuts thru waves and chop better.
Select to expand quotekobo said..eppo said..
I'm hearing more good things about this tail from someone who should be listened to. On the HA as expected but also the HS - especially the 1050!!
Winging or prone ? Was thinking of selling my 1050 after getting the 725, never thought I would do that when I got it !
Really???725 Must be unbelievable
Yeh mate , the 725 is faster than the 1050 ,turns as easily, but with more acceleration and glide. Pumps easier because there is less drag, only downside would be a higher stall speed. I'm still surprised how I can pump and connect on it for such a small wing.It's a high speed slicing machine !
