![Flight secrets: Pilots must descend plane quickly before oxygen masks run out | Travel News | Travel | Express.co.uk Flight secrets: Pilots must descend plane quickly before oxygen masks run out | Travel News | Travel | Express.co.uk](https://cdn.images.express.co.uk/img/dynamic/25/590x/Flights-secrets-oxygen-mask-time-1226057.webp?r=1578650080838)
Flight secrets: Pilots must descend plane quickly before oxygen masks run out | Travel News | Travel | Express.co.uk
![How Commercial Airplanes Keep a Steady Supply of Fresh Air and How the Emergency Oxygen Masks Supply Oxygen Given They are Not Hooked Up to Any Air Tank How Commercial Airplanes Keep a Steady Supply of Fresh Air and How the Emergency Oxygen Masks Supply Oxygen Given They are Not Hooked Up to Any Air Tank](http://www.todayifoundout.com/wp-content/uploads/2016/04/airline-oxygen-mask.png)
How Commercial Airplanes Keep a Steady Supply of Fresh Air and How the Emergency Oxygen Masks Supply Oxygen Given They are Not Hooked Up to Any Air Tank
![You could end up breathing in 'chemical dust' while using plane oxygen masks – The US Sun | The US Sun You could end up breathing in 'chemical dust' while using plane oxygen masks – The US Sun | The US Sun](https://www.thesun.co.uk/wp-content/uploads/2020/01/NINTCHDBPICT000423989747.jpg)