effective alternatives to horses and steam

有效替代馬匹和蒸汽

for powering public transport, wind,

用於為公共交通、風力發電。

in the form of large kites, were seriously considered.

認真考慮了大型風箏的形式。

But now after two centuries of development,

但現在經過兩個世紀的發展。

we still don't have kite powered buses.

我們仍然沒有風箏動力的巴士。

But we can do this.

但我們可以做到這一點。

The board flip.

棋盤翻轉。

Yes, the butter slide.

是的，黃油滑梯。

A nice fence for a grind.

一個好的柵欄，可以用來磨練。

Watch out for my post turn.

小心我的帖子轉。

And then there's this.

然後是這個。

The roll.

卷。

An airborne inverted spin.

一個空中的倒旋。

Nice work.

做得好

See you next time.

下次見。

That was an advanced version of a role.

那是一個高級版的角色。

A core kite surfing trick with plenty of variations.

一個核心的風箏衝浪技巧，有很多變化。

Kite surfers can front roll, back roll, roll, and nose grab.

風箏衝浪者可以前滾、後滾、滾、搶鼻。

There are all sorts of ways of mixing it up.

有各種各樣的方法來混合它。

And that wasn't one of them.

而這不是其中之一。

To perfect the right kind of airborne rotation for a kite

完善風箏在空中的正確旋轉方式。

surfing role requires a mastery of angular momentum and lift

衝浪的角色需要掌握角動量和升力。

force.

力。

Here's the roll 101.

這裡的卷子101。

As wind flows over a kite's wing-like shape,

當風流過風箏的翅膀狀時。

it generates lift force, pulling him across the water.

它產生升力，把他拉過水麵。

On launch, he throws his body backwards,

在發射時，他的身體向後拋去。

generating just enough angular momentum

產生足夠的角動量

for a complete rotation.

進行完整的輪換。

To land, he steers his kite downwards and ahead of him.

落地時，他將風箏向下和前方引導。

This increases lift force in the direction of travel,

這就增加了行進方向的提升力。

so he avoids sinking.

所以他避免了沉淪。

It is complicated stuff to deal with all at once,

一下子要處理的東西很複雜。

so first, let's just practice using lift

所以，首先，我們先來練習使用 lift

force to get a little air.

力來獲得一點空氣。

OK, We've got that covered.

好吧，我們已經得到了覆蓋。

Now let's add some angular momentum for the roll.

現在讓我們為滾動添加一些角動量。

I said, some.

我說，有些。

I mean, he did get enough angular

我的意思是，他確實得到了足夠的角度

momentum for one rotation.

一轉的動量。

But he didn't have time for two.

但他沒有時間去找兩個人。

OK.

好的

Let's work on the landing.

讓我們的工作在著陸。

Now, can you remember which direction

現在，你能記住哪個方向

we need to send that kite?

我們需要發送的風箏？

No, quite the opposite.

不，恰恰相反。

He actually aced the angular momentum,

他居然是個角動量。

But if you want to go in this direction,

但如果你想往這個方向發展。

like your board, and your kite is

喜歡你的衝浪板，你的風箏是

steered down in this direction,

朝著這個方向引導下來。

It's not going to happen.

這是不可能的。

OK.

好的

Last chance.

最後的機會。

Arguably worse.

可以說是更糟。

Lift force in wrong direction,

提升力方向錯誤。

Too much angular momentum.

角動量太大。

Very sinky landing.

很沉的降落。