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(helicopter flying)

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- [Tristan] We are here at Malmstrom.

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The helicopter provides

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security for the missile fields

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and a rapid response in case
anything were to happen.

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We also support

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missile field in general.

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Being able to take people out to the field

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in a timely manner is a pretty huge thing.

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Especially when the weather is real bad,

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which here in

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Montana can get pretty bad.

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So helicopters are
pretty amazing machines.

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They were developed first,

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in the 1930s

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and mass produced in the
1940s during world war II.

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And

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they are essentially air foils
that spin around in a circle.

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So,

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take your typical airplane wing,

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puts you on top of a,

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this helicopter in particular.

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And spin it around at a fast enough speed

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and that'll generate lifts.

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And then there's a bunch of
other aerodynamic principles,

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that you need to understand,

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in order to fly helicopter
successfully as the pilot

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and certainly were important
in developing the helicopter.

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[Tristan] Helicopter generates lift by

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spinning the rotor system
at a particular speed,

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for the Huey it's around 320
RPM (Rotations Per Minute).

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And that speed is constant.

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It's maintained during the entire time

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the aircraft is flying.

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And,

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as we pull in pitch

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or collective,

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it collectively changes,

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the pitch and the blade.

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So increases the angle of attack

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on the blades,

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that creates lifts and
pushes the helicopter up.

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So there are three
controls in a helicopter,

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the control flight,

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the CYCLIC,

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the COLLECTIVE,

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and the tail PEDALS.

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With the cyclic.

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That's how we control our front AF left,

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right,

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control the helicopter.

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The collective,

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collectively changes
the pitch in the blade.

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So that's how we go up
and down or add power

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and decrease power.

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And then the pedals,

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the antitorque pedals

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are what controls the

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swing of the tail

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in a hover or the

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yaw of the aircraft,

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there is a horizontal stabilizer in the

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tail boom section of the helicopter.

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And it's actually really
cool if you look at,

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because it's an upside down

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airfoil.

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It's an upside down wing.

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And the reason is,

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is because in forward flight,

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we actually

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use that to

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put force on the tail boom,

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so that the helicopter flies
more on a level attitude.

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[Tristan] So it's really
cool when you look at it,

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it looks like an upside down wing.

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And the pitch of that actually changes,

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with moving a cyclic forward and AFT.

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[Tristan] Drag definitely,

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is a pretty big factor in
how the helicopter flies,

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the body itself produces drag as you're

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traveling through the relative wind.

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And also

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the blades themselves,

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both the main rotor system
and the tail rotor system,

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create drag as a

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by-product of

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creating lift.

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[Tristan] Probably one
of the coolest things

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about flying a helicopter,

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is all the aerodynamic effects behind it.

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So,

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the tail rotor is doing a lot of things.

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The main rotor is doing a lot of things.

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And when the rotor is spinning,

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it's actually a,

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a disc.

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We stopped thinking about it
as two individual rotor blades.

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And we think about it as a rotor disc.

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With a

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helicopter,

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main rotor system,

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in order to fly forward,

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you have to increase the angle of attack,

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on the left side of the disc.

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The spinning rotor disc,

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so that the

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force generates lift in
the back of the rotor disc,

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in order to push the aircraft forward.

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So I thought that I always

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think that's a pretty cool principle of,

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flying a helicopter,

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really thinking about

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where and what is going on

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with all the aerodynamics
and the main rotor system

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and the tail rotor system.

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(slow upbeat music)