14 Questions
What happens to the percentage of Oxygen in the atmosphere as altitude increases?
Decreases with an increase in altitude
At approximately what altitude is the atmospheric pressure half the sea-level value?
18 000 feet
Up to what altitude can a healthy pilot operate without suffering the effects of hypoxia?
16 000 feet
At what altitude does the percentage of Oxygen in the atmosphere remain at 21%, by volume?
Throughout the majority of the atmosphere
Why do pilots need to breathe supplementary Oxygen when flying at high altitude?
Decreased atmospheric pressure, and a decrease in the partial pressure of Oxygen
What are the respective percentages of the gases that make up the atmosphere?
Nitrogen 78% Oxygen 21% Argon 0.95% Carbon Dioxide and trace gases 0.05%
At 36,000 feet, the air pressure is:
One tenth of the sea-level value
Breathing is regulated by:
Monitoring changes in the level of Carbon Dioxide in the blood
A smoker will feel the symptoms of hypoxia (Oxygen starvation) at:
A lower altitude than a non-smoker
On average, how long does it take to eliminate one unit of alcohol from the blood?
12 hours
The mechanism that maintains a constant flow of blood around the body is called:
The Circulatory System
How long after prolonged breathing-in of Carbon Monoxide must a pilot refrain from flying?
24 hours
Angina is caused by:
Insufficient blood reaching the heart muscle
Carbon monoxide is dangerous because:
Hemoglobin has 210 times the affinity for it than it has for Oxygen
Study Notes
Altitude and Atmospheric Conditions
- The percentage of Oxygen in the atmosphere remains at 21% by volume, regardless of altitude.
- Atmospheric pressure decreases with altitude, with the pressure being half the sea-level value at approximately 18,000 feet.
Pilot Health and Hypoxia
- A healthy pilot can operate without suffering the effects of hypoxia up to an altitude of approximately 12,000-13,000 feet.
- Pilots need to breathe supplementary Oxygen when flying at high altitude to avoid hypoxia (Oxygen starvation).
- A smoker will feel the symptoms of hypoxia (Oxygen starvation) at a lower altitude than a non-smoker.
Atmospheric Composition
- The atmosphere is composed of:
- Nitrogen: 78%
- Oxygen: 21%
- Other gases: 1%
Human Physiology
- Breathing is regulated by the respiratory center in the brain.
- On average, it takes one hour to eliminate one unit of alcohol from the blood.
Cardiovascular System
- The mechanism that maintains a constant flow of blood around the body is called the cardiovascular system.
- Angina is caused by a lack of Oxygen supply to the heart muscle.
Toxicology
- Carbon monoxide is dangerous because it binds to hemoglobin in the blood, reducing the Oxygen-carrying capacity of the blood.
- A pilot must refrain from flying for at least 24 hours after prolonged breathing-in of Carbon Monoxide.
Test your knowledge of Human Performance & Limitation (HPL) with this quiz covering topics such as percentage of oxygen in the atmosphere, atmospheric pressure at different altitudes, and the effects of altitude on pilots. See how well you understand these important factors for aviation.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
