NARRATOR: Like Yasuhiro Kubo here, going for a Guinness
world record title.
He'll be free falling from around 10,000 feet
and attempting to catch up with his parachute
attached to this canister.
The record is determined by how long he waits before jumping.
At 50 seconds later, off he goes.
[music playing]
Well, that was a relief--
and a world record.
Free falling without a parachute is one of the most
dangerous stunts imaginable.
Do not even consider considering to consider to do it, ever.
Especially when even regular skydivers have their off days.
A little help please, bro?
Go on, you can do it.
Go on.
Great, thank you.
All right, so how does a skydiver fall fast enough
to catch up with a parachute thrown
out nearly a minute beforehand?
Well, to find out, we need to brush up on terminal
velocity and air resistance.
As an object falls, it collides with trillions
of tiny air molecules, resulting in air resistance.
As the object accelerates, the air resistance acting on it
increases until it matches the force of the object's weight.
It's now at terminal velocity, the maximum speed
it could fall.
A larger surface area increases air resistance,
and so decreases terminal velocity.
A smaller surface area decreases air resistance,
and so increases terminal velocity.
A skydiver in spread eagle position
hits terminal velocity around 120 miles an hour
after about 12 seconds.
But for Yasuhiro to catch up with his chute,
that is just too slow.
So which of our wannabe record breakers
has remembered how we speed up our terminal velocity?
Not these ones.
That is the complete opposite.
Their raft has a large surface area,
thereby increasing air resistance
and slowing them down.
OK, anyone else?
Yeah, that's it.
Going upside down and reducing his surface area
decreases air resistance and increases terminal velocity.
Trouble is-- oh, whoa, it's very hard to control.
Oh, that guy upside down, too?
Yes, he was.
Once he's caught up with his chute,
Yasuhiro needed to steer himself into position to grab it.
How did he do that?
Well, skydivers can also use air resistance to maneuver.
For example, by adjusting his body shape,
this guy deflects flex more air backwards,
which pushes him forwards.
Bullseye?
Somehow, all of our high flyers were fine,
but I think we should leave the record to Yasuhiro.