Yes, planes have oxygen generators. While some aircraft use pressurized oxygen cylinders, most modern aircraft are equipped with chemical oxygen generators for emergency use.
Oxygen Generation on Aircraft
Commercial airplanes require a readily available source of oxygen for passengers and crew in the event of a cabin depressurization. This is typically achieved through one of two primary methods:
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Pressurized Oxygen Cylinders: These are tanks filled with compressed oxygen. This system is more common on smaller or older aircraft.
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Chemical Oxygen Generators: These devices produce oxygen through a chemical reaction. This is the more common method in larger, modern aircraft.
Chemical Oxygen Generators Explained
Chemical oxygen generators, often called oxygen candles, use a chemical reaction to produce oxygen. The most common chemical used is sodium chlorate (NaClO3).
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How They Work: When ignited by a firing pin (usually activated when the oxygen mask is pulled down), the sodium chlorate decomposes and releases oxygen. The reaction also generates heat.
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Location: These generators are typically located in the Passenger Service Units (PSUs) above passenger seats and in designated crew areas.
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Duration: The emergency oxygen supply, whether from cylinders or chemical generators, must last a minimum of 10 minutes, allowing the pilots time to descend to a lower altitude where supplemental oxygen is no longer required.
Advantages of Chemical Oxygen Generators
Chemical oxygen generators offer several advantages over pressurized oxygen cylinders:
- Lighter Weight: They are generally lighter than an equivalent supply of compressed oxygen.
- Lower Maintenance: They require less maintenance than pressurized systems.
- Compact Size: They are relatively compact, allowing for easier integration into aircraft design.
- Reliability: They are generally reliable and have a long shelf life.
Therefore, while some planes use pressurized oxygen, the majority utilize chemical oxygen generators as their primary source of emergency oxygen.
