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Density Altitude Training
Presented by: Breath of Fresh Air
Consultants
“We’ll Save You From Feeling
Under The Weather”
-Hunter Horton-Harmash
-Aaron Wermy
What is a practical definition
density altitude? (DA)
Density altitude is the air density given
as a height above mean sea level (MSL).
In simpler terms, an aircraft may behave
as though it is at a different altitude than
it actually is. Of the density altitude is
higher, the aircraft will experience
decreased performance.
What are the main factors
that affect density altitude,
and what changes in each
of those factors cause the
density altitude to increase?
Altitude, temperature, and humidity are the main
factors effecting density altitude. The higher the
altitude, the less dense the air is going to be. This
also applies to the temperature since the higher it is,
the less dense the air is. These two factors effect the
aerodynamic efficiency of the aircraft. The humidity
plays a role in deciding the necessary engine power
required. The higher the humidity, the more engine
power is suggested.
What are the hazardous effects of a high-density altitude
on aircraft performance?
High density altitude adversely affects the performance of an aircraft.
Takeoff distance, airspeed, and landing roll requirements are all increased
with a high density altitude. While these increase, the rate of climb of the
aircraft is decreased.
Is density altitude only an issue at high elevation
airports?
Density altitude can be an issue for
airports located at any altitude since
the temperature and humidity also
play a factor. For example, an
airport at a lower altitude can report
a density altitude much higher than
the airport's elevation. Therefore,
the aircraft would have to account
for those factors as if they were
landing at an airport who's elevation
matched the density altitude.
What season of the year is
density altitude generally
highest, and what time(s) of day
during this season are high-
density altitude conditions most
critical?
The summer months are
generally when density altitude
is at its highest. This is due to
the high temperatures and
humidity. This same factor is
why midmorning and mid
afternoon operations can be
hazardous.
What should be the
precautions taken, and
preparations made, when
planning a flight in high-
density altitude conditions?
Pilots wishing to operate in locations
with high density altitudes should
ensure that they understand the
affects it will have on the
performance of their aircraft. Since
high density altitude has a
particularly drastic affect on takeoff
and landing, pilots should ensure
that they determine the distances
that they need to perform these
actions.
Thank you for your attention!
Any questions, feel free to email us at
BOFAC@gmail.com
Training References and Useful Tools
https://wahiduddin.net/calc/calc_da.htm - a useful DA calculator where numbers can be plugged in and the
math calculations are done for you.
https://www.aopa.org/training-and-safety/active-pilots/safety-and-technique/weather/density-altitude - A great
pilot resource with additional information on density altitude.

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Density Altitude Training

  • 2. Presented by: Breath of Fresh Air Consultants “We’ll Save You From Feeling Under The Weather” -Hunter Horton-Harmash -Aaron Wermy
  • 3. What is a practical definition density altitude? (DA) Density altitude is the air density given as a height above mean sea level (MSL). In simpler terms, an aircraft may behave as though it is at a different altitude than it actually is. Of the density altitude is higher, the aircraft will experience decreased performance.
  • 4. What are the main factors that affect density altitude, and what changes in each of those factors cause the density altitude to increase? Altitude, temperature, and humidity are the main factors effecting density altitude. The higher the altitude, the less dense the air is going to be. This also applies to the temperature since the higher it is, the less dense the air is. These two factors effect the aerodynamic efficiency of the aircraft. The humidity plays a role in deciding the necessary engine power required. The higher the humidity, the more engine power is suggested.
  • 5. What are the hazardous effects of a high-density altitude on aircraft performance? High density altitude adversely affects the performance of an aircraft. Takeoff distance, airspeed, and landing roll requirements are all increased with a high density altitude. While these increase, the rate of climb of the aircraft is decreased.
  • 6. Is density altitude only an issue at high elevation airports? Density altitude can be an issue for airports located at any altitude since the temperature and humidity also play a factor. For example, an airport at a lower altitude can report a density altitude much higher than the airport's elevation. Therefore, the aircraft would have to account for those factors as if they were landing at an airport who's elevation matched the density altitude.
  • 7. What season of the year is density altitude generally highest, and what time(s) of day during this season are high- density altitude conditions most critical? The summer months are generally when density altitude is at its highest. This is due to the high temperatures and humidity. This same factor is why midmorning and mid afternoon operations can be hazardous.
  • 8. What should be the precautions taken, and preparations made, when planning a flight in high- density altitude conditions? Pilots wishing to operate in locations with high density altitudes should ensure that they understand the affects it will have on the performance of their aircraft. Since high density altitude has a particularly drastic affect on takeoff and landing, pilots should ensure that they determine the distances that they need to perform these actions.
  • 9. Thank you for your attention! Any questions, feel free to email us at BOFAC@gmail.com
  • 10. Training References and Useful Tools https://wahiduddin.net/calc/calc_da.htm - a useful DA calculator where numbers can be plugged in and the math calculations are done for you. https://www.aopa.org/training-and-safety/active-pilots/safety-and-technique/weather/density-altitude - A great pilot resource with additional information on density altitude.