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PARACHUTE FABRICATION
by Levi Westra
Introduction
Parachute fabrication requires time, skill, knowledge of fabrication techniques as well as appropriate tools and materials. This resource is intended to provide information on the "how and why" of the last three components. By providing this information the iteration segment of design will be quickened by reducing number of iterations and time needed for information gathering on construction.
Method
Parachute construction data was gathered and correlated from websites and textual resources as well as first hand experiences.
Results
Below is a morphological chart which lists all the functioning parts of a parachute as well as the different means at creating these parts. Use of morphological charts is described by Clive L. Dym and Patrick Little in their book, Engineering Design. The chart is used to choose a particular means for each component of the parachute. The particulars for each mean are described in detail following the chart.
Function: |
Means: |
| Canopy Shape |
Circular |
Square |
Hexagonal |
*Hemispherical |
------- |
------- |
| Parachute Material | Garbage Bag | Dry Cleaning Bag Material | Mylar Film | Tight Weave Cloth | Rip Stop Nylon | ------ |
| Shroud Line Material | Cotton Kite String | Monofilament Nylon Line | Sewing Thread | Braided Nylon Line | Dental Floss | ------ |
| Shroud Connection to Canopy | *Gathered Canopy | Taped | Glued | Sewed | ------ | ------ |
| Fastening Shrouds at Load Carrying ends | *Loop | *Swivel Snap | ------ | ------ | ------ | ------ |
| Cutting out Canopy | Scissors (sharp) | Utility Knife | Paper Cutter | ------ | ------ | ------ |
* These means are described in more detail below
Details of Selected Means
*Hemispherical Shaped Canopy
The other canopy shapes are flat, single pieces of material cut to shape. Technically they are called Para sheets. The hemi spherically shaped canopy is not a single flat sheet of material, but many pieces (gores) attached to each other, this is commonly referred to as a "true parachute". A detailed description of constructing a hemispherical canopy can be found on Richard Nakka's website
*Gathered Canopy
A gathered canopy shroud connection is created by gathering a small amount of material at the corner of a Para sheet and tying the shroud line around that gather. This technique is most effective on the non-circular Para sheets. A benefit of the gathered technique is it creates parachute that is similar to the hemispherical shaped canopy.
*Loop
The loop is created by using a single piece of shroud line to span the canopy
The other shrouds are gathered together and a loop is made
This is a robust example of a loop
*Swivel Snap
Commonly Used for fishing lures.
Example of using the Morphological Chart:
Parachute Shape: I choose the Hexagonal Shape
Parachute Material: I choose the Mylar Film
and so on...