Welcome Guest. Sign in or Signup

2 Answers

Pressure / Density Altitude – More / Less Dense – High / Low Temperature Help

Asked by: 1781 views General Aviation, Weather

I haven't yet been able to crack a consistent memory aid for how to remember the specifics of pressure altitude, density altitude, how temperature affects density and high /low temperature vs high/ low elevation....

Anyone have a mnemonic or acronym or phrase to help me with this? Something is just not clicking and for the life of me I can't consistently remember where it's more dense vs less dense, how that relates to density and throw pressure altitude into the mix, the topic as a whole is something I'm struggling to master. Any tips?

Ace Any FAA Written Test!
Actual FAA Questions / Free Lifetime Updates
The best explanations in the business
Fast, efficient study.
Pass Your Checkride With Confidence!
FAA Practical Test prep that reflects actual checkrides.
Any checkride: Airplane, Helicopter, Glider, etc.
Written and maintained by actual pilot examiners and master CFIs.
The World's Most Trusted eLogbook
Be Organized, Current, Professional, and Safe.
Highly customizable - for student pilots through pros.
Free Transition Service for users of other eLogs.
Our sincere thanks to pilots such as yourself who support AskACFI while helping themselves by using the awesome PC, Mac, iPhone/iPad, and Android aviation apps of our sponsors.

2 Answers



  1. awair on Jul 11, 2022

    There is boldmethod page that describes this well, no mnemonics but good illustrations that help it stick…

    https://www.boldmethod.com/learn-to-fly/performance/density-altitude/

    +1 Votes Thumb up 1 Votes Thumb down 0 Votes



  2. mjc123 on Dec 18, 2022

    To remember the relationship between temperature and density, it can be helpful to think of the phrase “hot air rises.” Hot air is less dense than cold air, so it will rise in the atmosphere. When the air temperature is high, the density of the air will be lower, resulting in a higher density altitude.
    To remember the relationship between altitude and density, you can think of the phrase “thinner air at higher altitudes.” As you climb higher in the atmosphere, the atmospheric pressure decreases, resulting in less dense air. This means that the density altitude will be higher at higher altitudes.
    One acronym that can help you remember the relationship between these variables is “HALD,” which stands for “Hotter Air Less Dense.” This acronym can help you remember that high temperatures and high altitudes both result in less dense air and therefore higher density altitudes.

    0 Votes Thumb up 0 Votes Thumb down 0 Votes


The following terms have been auto-detected the question above and any answers or discussion provided. Click on a term to see its definition from the Dauntless Aviation JargonBuster Glossary.

Answer Question

Our sincere thanks to all who contribute constructively to this forum in answering flight training questions. If you are a flight instructor or represent a flight school / FBO offering flight instruction, you are welcome to include links to your site and related contact information as it pertains to offering local flight instruction in a specific geographic area. Additionally, direct links to FAA and related official government sources of information are welcome. However we thank you for your understanding that links to other sites or text that may be construed as explicit or implicit advertising of other business, sites, or goods/services are not permitted even if such links nominally are relevant to the question asked.