ClimbCheck FAQ
Answers to common questions about density altitude, pressure altitude, takeoff performance, runway margin, baseline takeoff distance, and how to use ClimbCheck safely as a planning and training aid.
What is density altitude?
Density altitude is pressure altitude corrected for non-standard temperature and, in more complete calculations, humidity. It helps pilots understand how aircraft performance changes when the air is less dense than standard conditions.
How is pressure altitude calculated?
ClimbCheck calculates pressure altitude from field elevation and altimeter setting or QNH. The result can be edited manually if you already have a known pressure-altitude value.
Does ClimbCheck replace my aircraft POH or AFM?
No. ClimbCheck is an educational planning aid and runway-margin awareness tool. Always verify final performance with the aircraft AFM/POH, official weather, runway conditions, aircraft configuration, and pilot judgment.
Why do I enter a baseline takeoff distance?
The baseline takeoff distance should come from your aircraft performance reference, normally the aircraft AFM/POH or another aircraft-specific performance reference. ClimbCheck then estimates how density altitude and the selected model change that baseline distance.
What is runway margin?
Runway margin is the runway length remaining after the estimated required takeoff distance is subtracted from available runway length. It is a planning signal, not an operational clearance.
Which performance model should I use?
The Precise model is recommended for most normal use. Legacy Koch is useful for comparing classic Koch chart-style estimates, and Rule-of-thumb is best for a quick ballpark check.
Can I use ClimbCheck for landing distance?
The current version focuses on takeoff performance. A future landing runway-margin feature may be added using pilot-entered POH/AFM landing distance as a baseline.
Educational planning aid only. Always verify aircraft performance with official weather, runway data, AFM/POH performance charts, and pilot judgment.