Aeronautical Engineering Development of Atmospheric Probes

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Designing of Atmospheric Probes by Primitive Means
Abstract The sole goal of the week was to create
an atmospheric probe that could be shot from a
compressed air cannon and safely descend back to
the earth. We endured many probe failures before
a success was finally reached. Our final design
was to have a rocket body that is cut entirely in
half and loosely wrapped with string. With proper
timing, the loose string will unravel just as the
probe reaches apex, allowing the two halves to
separate, deploying the parachute. This design
was the most successful since the parachute will
always deploy. After creating a successful probe,
we focused on hang time and made that our main
goal.
Design In order to have a probable release of
the parachute, the body of rocket was cut
strategically so that the rocket will fall away
and initiate parachute deployment. In order for
the parachute to deploy at the apex, we wound a
line of string around the body of the rocket so
that it would stay together. As the string
loosened the parachute would then deploy as the
two halves fall apart and the parachute would
start to descend downwards. The parachute, and
its attached probe, then fall to the ground.
Different shooting and string-wrapping techniques
were tested to optimize the probes hang time.
Second probe that was too large for 3 inch barrel
Results Our probes, first and last, were not
successful. Initially our parachute did not
deploy at all. However, after extensive work on a
new design and probe we became more successful.
Our parachute began to deploy, however it did not
inflate and the probe still fell hastily to the
ground. After modifications , we were able to
ensure parachute deployment , though inflation
was still unreliable.
Materials Water bottle Duct Tape Foam Plastic Str
ing Hot glue Wire Washers
Errors We encountered many problems in the
launching of our probe. Our first design was
defective for it was too large for the 3 inch
launch barrel. When loading it into the 3 inch we
would push down upon the cone and it would be
forced into the body of our probe, jamming it
inside. This made our parachute unable to deploy
thus our probe would catastrophically fail and
fall directly back to earth. Our second design
was more successful than our first after
reviewing our errors. The second probe though
still had some faults. When the halves of our
probe split apart and our parachute deployed we
noticed that our parachutes weight was missing.
We soon learned that the force of the launching
ripped off our weight thus our parachute would
not work properly.
Conclusion Even though our probes were not
entirely successful we believe that with more
time we can perfect our design. With the use of
simple materials we believe we can contribute to
the future development of Aeronautical design.
Very first probe that catastrophically failed
immediately in testing phase
Angie Forbes, Sarah Leary, Melissa Suursoo, Chris
Cheng