How to tuck

**enemy combatant** · 12-31-2007 01:58 PM

Originally Posted by the Kyle Seigler

(correct me if I'm wrong)

OK. 9.8 m/s**2 is the acceleration of any mass near to earth by gravity. This force is also called weight. On the inclined plane of a hill the weight must be multiplied by the sin of the angle of the slope. When aerodynamic drag (and in the case of a downhill skater the additional friction of both the wheels on the pavement and the bearings) equals the skaters weight then acceleration ceases. This is called the terminal velocity:

Terminal Velocity

**Pat S** · 12-31-2007 04:16 PM

Also, objects don't have a terminal velocity in a vacuum. (provided a constant force)

**Crappysurfer** · 12-31-2007 04:32 PM

im pretty sure terminal velocity only applies to things in free fall, AKA falling from the sky...
and Pat S, none of us are skating in vacuums

**Longbord1** · 12-31-2007 04:37 PM

martin siegrist stated that he cannot keep up with erik and mischo because of their weight. They are just as aero as he is but that extra bit of mass lets them murder him in the straights. However, his cornering skills make up for that.

**enemy combatant** · 12-31-2007 04:40 PM

Originally Posted by Crappysurfer2

im pretty sure terminal velocity only applies to things in free fall, AKA falling from the sky...

Nonsense, objects rolling down a hill also have a terminal velocity as I explained above.

**HerBDerb** · 12-31-2007 04:40 PM

Originally Posted by Crappysurfer2

im pretty sure terminal velocity only applies to things in free fall, AKA falling from the sky...

No, terminal velocity can be applied to pretty much any situation where air resistance is involved, you just need the right formulas.

**Pat S** · 12-31-2007 05:10 PM

Crappysurfer, then how do you explain this?

.

But really, i was just correcting Kyle Seiglerr. And yes things rolling down a hill also have a terminal velocity.

**the Kyle Seigler** · 12-31-2007 06:03 PM

Originally Posted by enemy combatant

OK...

Terminal Velocity

Thank you for the clarifications. That makes a little more sense--great link too.

-kyle

**TheRosen** · 01-03-2008 12:29 PM

Edit: quoted the wrong person..... ><

wow i just tried that outn yesterday before reading this... love it. wasn't on too big of a hill, but the transitions between turning and tucking felt really good, and it feels a damn bit more aero then regular brazillian. i just want to see if its as fast then euro. next time i go out on a big hill thats what im doin.... any more experienced riders have thoughts on this position?

**Byrne Burnham** · 01-03-2008 06:11 PM

It was actually the terminal velocity that helped me become more familiar and COMFORTABLE with DH'illing.....

Go for it - push for further - and stop just short of when you'll sh*t your pants.....SMILE

Seriously, that's how it worked out for me.....

**Xgecko** · 01-03-2008 06:41 PM

Originally Posted by Byrne Burnham

Go for it - push for further - and stop just short of when you'll sh*t your pants.....SMILE

yeah that's the policy that I've been working on....so far it's been making me a bit faster...and my drawers are still clean

**roadthRASHr** · 01-03-2008 07:28 PM

yea its true that heavier riders have a larger profile than a lighter rider, but their volume(weight) to surface area ratio is bigger than lighter riders. so this will makes them faster in straightaways. its like, how much bigger a profile is a 200lb rider compared to a say, 100lb rider? its also like, when ur in the ocean and its cold, the 100lb person gets colder because their volume to sfc area is smaller than the other one.....hahaha i guess thats kind of a confusing comparison.

that moon pic is pretty cool.

**buggybomber** · 01-06-2008 02:53 PM

when i tuck i have my knee on the board
is that bad

**neuros** · 01-06-2008 03:02 PM

no, unless you don't like it. I find that a knee actually on the board throws off my balance and is hard to get out of very quickly.

**tsmith25** · 01-07-2008 12:07 AM

my weight advantage deosnt seem to help much till 30 mph and above. has anybody else seen this where the weight deosnt make much difference if the speed is too low?

**hexagon5un** · 01-07-2008 09:03 AM

Originally Posted by tsmith25

my weight advantage deosnt seem to help much till 30 mph and above. has anybody else seen this where the weight deosnt make much difference if the speed is too low?

Your weight "advantage" only gives you a higher terminal velocity than a lighter rider of the same size. You and the other skater both accelerate at the same rate, and only stop accelerating when the wind resistance pushing on you is equal to the component of gravity pulling you forward. The more massive rider gets more gravity pulling on him (that's what we call weight) so if both riders are the same size and have the same tuck, the heavier rider will top out at a higher speed. (On the same hill.)

Whatever you get out of weight will only show up as your speed exceeds the terminal velocity of the other skater. Below the other skater's terminal velocity, you two will (ideally) be going the same speed from a standing start. For a medium-steep hill and a good tuck, 30ish sounds about right.

**assumeivan** · 01-07-2008 09:34 AM

I think I might try to make a "Mythbusters 2" video. Straight downhill, no turns, timed from start to finish. Maybe strap some ankle weights and other weights on.

**assumeivan** · 01-07-2008 10:55 AM

Originally Posted by DaddyYo

All the illustrated tuck stances seem very tall. Wouldn't you be more stable and areodynamic if you were tucked so low that you were just about sitting on the deck?

I know foot braking would be more difficult but could braking be done instead by dragging a gloveed hand designed to brake rather than slide?

I think an effective tuck relies more on air flow around the body rather than how low and small you are. Braking with hands isn't too effective either. You really, REALLY shave down on your pucks. It also takes you much longer to slow down. I used to use my gloves to brake when I was just starting; it didn't work too well.

Your point on tucking so low that you were basically sitting on the board is similar to a Brazilian tuck.

**tsmith25** · 01-07-2008 03:49 PM

daddyo there is one euro rider that i have noticed in videos using his hands to brake.

ivan im sure he didnt mean with slide pucks.

i have though about putting rubber on my knuckles of my glove to allow for small speed adjustments during corners but havent tried it yet. maybe bring trail braking to dh. i guess drifting is technically trailbraking...

hex i wasnt really talking about terminal velocity. i just meant that at speeds under 30 the lighter riders seem to keep up better. when we ride parking garages its pretty even with the little guys even having a small advantage since they can hold a little more corner speed.

**Iceman** · 01-07-2008 05:12 PM

Originally Posted by DaddyYo

All the illustrated tuck stances seem very tall. Wouldn't you be more stable and areodynamic if you were tucked so low that you were just about sitting on the deck?

When you get below a certain point, your body starts to go more vertical which catches more air. There is always a compromise. The bottom line is that for straightline speed, laying down seems to be the best method. That's why lugers are faster than stand-up. I've never had the opportunity to try one though. Would like to someday.