Parks College Parachute Research Group

PIMS, the Parachute Inflation Modeling Suite program

written by Dr. Jean Potvin and Gary Peek


Since 2001, the US Army Natick Solider Center and the US Army Yuma Proving Ground have been funding the Parks College Parachute Reseach Group for the development of a new software platform aimed at providing a user-friendly computer program for the the simulation of parachute inflation. Known as PIMS, or Parachute Inflation Modeling Suite, this Windows-based platform uses a Graphical User Interface (GUI) to facilitate data entry and graphing.

The ultimate goal is to use almost all inflation models that have been published in aeronautical literature to simulate a wide variety of parachute systems, from round-types to ram-air wing types, with or without line or slider reefing.

The PIMS Program

The following graphics files are screen shots of various windows in the program.

PIMS can generate graphs of speed, force, drag area, or a combination of the three. The following graph shows the force simulation for a (nominal) Performance Designs Stiletto 150 ram-air parachute.

(This graph can be copied to the Windows clipboard where it can be pasted into other programs that can generate a graphic file.)

Main graphing window


PIMS can model many types of parachutes, which can be selected in the following window.

Model type selection window


Each type of parachute has design parameters specific to that parachute. The following window is for one of the parachute types and allows the parameters to be entered.

Parachute specific parameters window


Selected information, input parameters, and calculated values related to the simulation can be viewed in the following window.

Selected simulation data window


The PIMS program includes a feature that allows the user to output graph data in space-delimited ASCII file format. This data can then be imported into many other programs for further analysis.

The following spreadsheet graph is a combination of force simulation data generated by PIMS along with the actual data collected with force reading instrumentation during the inflation of a ram-air parachute.

Spreadsheet graph of simulated and actual data


log file