The KochChart Density Altitude Software Tool

Introduction

Welcome! This site is your source for the KochChart educational software tool. This tool compares various estimating methods (including, but not limited to, the Koch Chart) for assessing the impact of density altitude on take-off and rate-of-climb performance. In addition, the tool can estimate the effects of wind, runway slope and runway surface on take-off distance.

This is a free educational tool created to raise awareness about the significant effect density altitude has on aircraft performance, and is especially important for pilots flying at high-elevation airports.

Why the name 'Koch Chart'? This program started as a relatively simple digital version of the venerable Koch Chart nomograph (the roots of which are somewhat obscure). The user would type in key parameters to produce the chart. But eventually automated METAR collection and others' estimating methods were included. Now the program does much more than produce a Koch Chart, but the name lives on!

The algorithms used in the software were originally developed for light, single-engine, normally aspirated (i.e., not-turbocharged) piston aircraft. They are not applicable to other types of aircraft.

Downloads

You can download the KochChart software at this page. Look for the release withLatest badgeafter the release name.

Currently, the software is only available for Windows.

Instructions

You can view an instructional video here:

And the software was also featured in a Colorado Pilot's Association webinar, which included a detailed demonstration of the software. It can be viewed here (the software discussion starts at around the 32-minute point in the video):
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KochChart Disclaimer and License Agreement - Not for Flight Planning

By using the software, you agree to the following terms:
  1. Educational Use Only: This software is provided for instructional and educational purposes only. It does not meet the requirements of Federal Aviation Regulation (FAR) section 91.103 "Preflight Action" or any other regulation.
  2. No Operational Use: This tool is not approved for flight planning or operational decision-making. Pilots must always consult their official Airplane Flight Manual (AFM) or Pilot's Operating Handbook (POH) for performance calculations.
  3. License Terms: This software is free for personal, non-commercial use. Redistribution, modification, or commercial use is prohibited without prior written consent from the author.
  4. No Warranty: This software is provided "as is," without any warranties or guarantees of accuracy, saftey, or fitness for any purpose. Use at your own risk.

Supporting KochChart

The KochChart software is free, but if you would care to make a donation to its maintenance and future improvements, you can do so here. There is absolutely no obligation to do so. I hope you enjoy the software!
    --Jim Greer

Questions and Feedback

Have a question or feedback? Contact me via GitHub
...or use the Contact Form below.

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