WEBVTT

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Since the 1950s, NASA has studied how to land
spacecraft on planetary bodies,

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as the entry, descent and landing phase can be

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the greatest challenge for destinations with an atmosphere.

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The first atmospheric entry tests used ballistic missiles with long, narrow nosecones, but

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their high speeds and low drag caused
overheating and melting of the rockets’ surfaces.

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So, NASA researchers tested blunt-nose reentry
vehicles that reduced heat transfer

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by increasing drag compared to traditional shapes.

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While blunt body designs work well,

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engineers and scientists at NASA Langley Research Center

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developed a more versatile concept --

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a Hypersonic Inflatable Aerodynamic Decelerator,
or HIAD.

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The inflatable spacecraft technology is made
up of strong, yet flexible fabric, designed

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to maintain its shape and withstand the heat
and force of rushing through an atmosphere,

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offering reduced mass and increased size,
both crucial in space travel.

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During launch, the uninflated stacked rings
are packed inside a bag,

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and right before the spacecraft enters the
atmosphere,

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a compressed gas system increases the volume
of the inflatable structure.

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Entry, descent and landing of any spacecraft

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to a destination with an atmosphere create
some unique, but common problems.

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First, the vehicle must be slowed down enough to safely land.

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In order to use the atmosphere to slow the vehicle,
engineers have to increase

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the Aerodynamic Drag on the vehicle.

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Drag is the aerodynamic force that opposes
an aircraft’s motion through the air.

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To land twice the mass,
the vehicle must have twice the drag area.

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By increasing the diameter of the vehicle,
engineers are able to deploy larger vehicles.

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But the second problem, heat, requires that
vehicles have a thermal protection system.

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As a vehicle traverses the atmosphere,
a large amount of friction is created.

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The impact of the air molecules on one another
transfers a great deal of heat to the surface

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of the entry vehicle,
in a process known as Aerodynamic Heating.

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Unlike traditional aeroshells, HIAD is much larger in diameter,

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allowing the heat to spread over a larger surface area.

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In a HIAD, several materials are combined together in layers
to insulate the larger inflatable heat shield,

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providing effective heat resistance and
 making HIAD a unique solution

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for the problems of entry, descent and landing.

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Inflatable technology could give
NASA more options for future planetary

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missions as it can be used on any planet or object in space

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that has an atmosphere.

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This new tech will advance space exploration,
both robotic and human, allowing new scientific

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discoveries, changing the way we explore new
worlds.

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By measuring atmospheric heating with balloons,
students will be able to discover the

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difference between qualitative and quantitative data;

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collect, organize and interpret data;

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and use their data to explain transfer of heat energy.