How Airplane Oxygen Masks Work Given They Aren't Hooked to Tanks & How Planes Get Oxygen at Altitude

TL;DR

Airplanes use a clever system to provide oxygen to passengers, involving the compression and cooling of outside air, and chemical oxygen generators in the masks.

Transcript

Because the economics of having large oxygen tanks aboard airliners simply doesn't work out (not to mention that the air quality inside the plane would rapidly become unpleasant if fresh air wasn't constantly supplied, regardless of the oxygen levels), commercial airplanes have a very clever system installed to solve the problem of ultra-low pressu... Read More

Key Insights

• ✈️ Airplanes use a system of bleeding off compressed hot air from the engines and cooling it to provide oxygen to passengers during flight.
• 👱 The existing air in the cabin is continuously vented out, ensuring that fresh air is constantly being circulated.
• 🛩️ Oxygen masks in airplanes rely on small chemical oxygen generators, which produce oxygen through a chemical reaction.
• 😷 The rate of oxygen generation may not fully inflate the mask bags due to factors such as poor seals, deep breaths, or continuous oxygen flow.
• 😘 The ultra-low humidity levels and low cabin pressure in airplanes can cause dehydration and reduced sense of taste and smell.
• ⌛ Humans predominantly breathe through one nostril at a time, with periodic switching.
• 🧠 The nasal cycle has been found to affect various physiological and cognitive aspects of the body, including glucose levels and brain hemisphere dominance.

Questions & Answers

Q: How do airplanes provide oxygen to passengers during flight?

Airplanes use a system that involves bleeding off compressed hot air from the engines, cooling it, and piping it into the cabin to ensure sufficient oxygen levels for passengers.

Q: Why do airplanes maintain cabin air pressure at 12 psi instead of sea-level pressures?

12 psi is sufficient for the majority of passengers while reducing structural strain on the aircraft. Sea-level atmospheric pressures would put more stress on the aircraft.

Q: How do airline oxygen masks work?

The masks are not connected to any centralized oxygen tank or air line. When the mask is pulled, a small explosive charge sets off a chemical reaction in oxygen generators, producing oxygen for the mask.

Q: Why don't the plastic bags on the masks always inflate?

The bags serve as a reservoir for oxygen, but they may not always inflate due to factors such as a poor seal, rapid deep breaths, or the continuous flow nature of oxygen generation.

Summary & Key Takeaways

• Airplanes solve the problem of low atmospheric pressure at cruising altitudes by bleeding off compressed hot air from the engines and cooling it before piping it into the cabin.

• Pressurized air with sufficient oxygen density is continuously supplied to the cabin, while the existing air is vented out through an outflow valve.

• In case of cabin pressure loss, oxygen masks deploy, and the oxygen is generated through small chemical oxygen generators in the masks.