I had a bad experience last winter when the wind got under the board and it proceeded to do a kind of fairly ugly side loop thingy. It was 4.0 mtr weather, flattish water considering it was howling.
My question is: When choosing a smaller board for these conditions, is it the smaller volume, or the smaller surface area that makes it controllable (or my skill level)?. I weigh 78ish kg and was looking at a 68ltr Mistral Beast. Smallest board I've had was a 86ltr Mistral Electron which I considered quite floaty. The smallest sail I have is a 3.4 mtr.
i reckon 68lt is a bit small for you mate.you will sink like a stone in the lulls
Try something around 72-75lt should be fine for your weight.
I'm sure others will tell you all about board width, fin size mast foot position, and rockers lines,I will leave that to them
to help answer your question:
what level are you and where do you sail when its that windy.
If your fin is a little too big it will generate too much lift and your board will want to tail walk and become airbourne.
Is it when you are sailing along? Ive had the board blown 50mt downwwind when the wind flips it waterstarting or chophopping but I just thought that was normal for strong winds..30kts + gusting to ..>>
As OB64 mentioned, it could have been too much fin, but it could also have been a lack of mast foot pressure.
When it's howling and a strong gust hits, the (my) first instinct is to get defensive and sheet out. this reduces MFP, and the nose will rise. You'll need to try to keep the pressure on - stay sheeted in with your weight in the harness.
When I get overpowered in the gusts, I'll pull on some more outhaul (with an adjustable outhaul) and point higher into the wind. It's how formula sailors can handle those 10-12m sails in 25 knots.
All of the above.
Overfinned.
Not enough MFP (Boom too low?)
Wind gets under the nose of the board and blows it around (volume & area too large for the conditions)
not eating anought maccas, yummm.. I am 130 kilos, before when I use to be skinny my board use to lift all the time in those melbourne gales. now I am fine my wave board is a 120 litres and its a sinker for me. donuts, maccas all helps and plenty of red bull..
Mate, I was sailing once in about 30 knts of wind on dead flat water, the board was a 93 litre axxis, sail 5 m and I think fin 27 cm. All of sudden the wind just pick me and my kit up to a few metres in the air and just slammed me down 
Very unsettling as you say.
I moved the mast track all the way forward and kept more pressure on my front foot and it did'nt happen again. So technique can help as well as the right gear 
75 to 80 litre wave board with a 21 or 22cm fin, perfect for windy days, heap more control in chop and you can jump it.
Simmo - he is only 78kg - 75-80L would be his summer Dutchies board........
I agree with the 68L for a howler
Thank you for your input. From most of the info I seem to be on the right track, boom high, 23 cm Choco weedy, and who knows, the day I came unstuck I may have not been sheeted in hard.
I am a little confused by the "body weight minus 10kg" guide. 78kg less 10 = exactly the size board I was looking at, but as a percentage I am using a smaller board than a 110 kg guy on a 100ltr. (I think?)
Thanks again. Although with the amount of wind we've had over the last 3 months this is a pointless discussion anyway, but I want to be ready! 
Krisiz1 - I'm about 5kg heavier than you, I think 68L might be a bit small unless you have 3.4 winds all the time.
Am I right in thinking the electron is a bit older and longer than current boards? That shape does make it lift up far more easily than a more modern and compact board. I think if you had a more compact board, with the volume in L just under your weight in kg, you would find that pretty good and not have the sinking all the time problem. e.g. my smallest board is about 5 liters under my weight and happy on a 3.7 - but it's 222cm long and a twin which is pretty different to an electron, so carries the volume better.
So maybe you don't need to sacrifice so much volume if you get a more modern shape.
)
for me it gets down to sail size and not board size.
sailing south beach in a geniune 30 knots, it was not my 80 litre slalom board that was the problem, it was my 5.0m was too big for my less than 70kg.
have since sailed my 3.3m in similiar winds, albeit on the river and the board control was chalk and cheese.
in 25/30knots on 3.3m in control, above 30 started sheeting out, a big difference than on my 5.0m.
when you start sheeting out this reduces board control,promoting spinning out, excess lift etc.
i have a 70 litre slalom board and it is no faster or controllable in the strong stuff than my larger board.
a small fin helps,25cm or less,then again i have heard from a few that going a bigger fin esp in choppier water is the way to go,can't see it myself.
buying a really small sail makes sailing in strong wind so much more enjoyable,and you can sail all day,instead of sailing an hour and packing up!
Spot on
I'm 85kg and I've got a 2008 JP FSW carbon 77. It's really light and takes off at nothing. Sailing it over powered on a 4.5m is practically impossible but dropping to a 3.7m and it becomes loads easier..
