UA.III.B.K1a Drone Certification 2019 - Density altitude

Описание: --Best experience is with headphones--
Training Sequence: NOOBS 73 of 82
I hope that you are able to pass the exam with these free videos, free visually intense study guide and 125+ free questions! GOOD LUCK!

Drone Safety Academy's PROFESSIONAL GRADE learning portal provides a GUARANTEED process for NOOBS (500+ questions) & Recertifying pilots (350+ questions) if you are interested. NOOB means New Out Of Box and thus new to drone certification.

Drone Safety Academy learning portal (includes the free study guide which is updated monthly and a link to the free questions...look in the upper right hand corner for the link):
http://bit.ly/Learning_Portal_Drone_S...

Drone Safety Academy official website:
http://bit.ly/Drone_Safety_Academy_Of...

Drone Safety Academy YouTube channel:
http://bit.ly/YouTube_Drone_Safety_Ac...

Share your success with us!

UA.III.B.K1a Density altitude
Source [AIM: 7-5-6 i, PH: 8-7 & 11-3]

Most of the language is this section involves manned aircraft, but the principles and effects remain the same with sUAS operations and the FAA believes that the sUAS pilot should understand the effects of density altitude.
NOTE: This section is about “Density Altitude” and understanding when it is high density altitude or low density altitude.

To better understand this section a review of a few principles of physics in two parts.

Part 1)
The effect of temperature on molecules. Consider a cubic container of air A) 0 Celsius (32 Fahrenheit) now consider two other containers or air. B) One at 15 Celsius (59 Fahrenheit), and C) 30 Celsius (86 Fahrenheit). Container A will have more air molecules than the other two because the colder temperature reduces distance between molecules and slows down the movement of the air molecules. Therefore, more molecules will fit into container A when compared to B & C. Container C will have the least number of molecules because the heat increases the distance between molecules and increases the movement.

Part 2)
Propeller and aircraft lift efficiency. A spinning propeller, in air, pushes air molecules to provide thrust and/or lift. Now let’s consider the temperatures stated in part 1 to achieve 100 feet of aircraft lift at an arbitrary altitude of 4000 MSL for each temperature: A propeller in a temperature of 0 Celsius (32 Fahrenheit) might only have 800 revolutions per minute (rpm) to achieve the 100 feet of lift (efficient). A propeller in a temperature at 15 Celsius (59 Fahrenheit) might have 1000 revolutions per minute (rpm) to achieve the same 100 feet of lift at the same altitude (less efficient). A propeller in temperature of 30 Celsius (86 Fahrenheit) will have to work harder with 1200 revolutions per minute (rpm) to achieve the 100 feet of lift (least efficient). All this at the same altitude!
‘Density Altitude’ is better explained with an introduction of ‘Pressure Altitude’: ‘Pressure altitude’ (a measurement) describes the normal or standard conditions of atmospheric pressure at any altitude (a baseline). Any deviation from this normal/standard is called ‘Density Altitude’. For the purpose of this training ‘density altitude’ may be explained as either high or low.

When conditions are standard/normal (altitude and temperature), ‘pressure altitude’ and ‘density altitude’ are the same.

So, for the exam, ‘density altitude’ is (atmospheric) ‘pressure altitude’ corrected for variations from standard temperature.

‘Density altitude’ is a measure of air density at specific temperatures at specific altitudes and is used as a determining criterion in the performance capability of an aircraft.

Performance figures in an aircraft owner’s handbook are generally based on standard atmosphere conditions at sea level with a surface temperature of 59 degrees Fahrenheit (°F) or 15 degrees Celsius (°C) and a surface pressure of 29.92 inches of mercury (“Hg) or 1013.2 millibars (mb).

For the exam you need to understand:
Air density decreases with altitude
The effects of higher than standard temperatures result in an increasing high ‘density altitude’ condition.
High ‘density altitude’ reduces all aircraft performance parameters.
#DroneSafety #DroneCertification #UnmannedAircraftTraining