Seatbelts and airbags in cars save passengers lives. Parachutes save people who, for a variety of reasons, exit a plane in mid-flight. So why aren’t parachutes provided to passengers on commercial airline flights, in case of emergencies?

Because they almost certainly would not save anyone’s life.
Parachuting Basics
When your average daredevil skydives for fun, the plane is typically travelling at between 80 and 110 mph when the skydiver jumps.
Four to five hours of intense ground instruction, including learning body flight maneuvers and hand signals that instructors use to coach the student as they fly alongside.
When skydivers leave a plane, they do it alone or in small groups. When successive groups will be jumping, they try to keep separated by anywhere between 500 and 1500 feet; this is often accomplished by waiting until the preceding group is “back under the tail to 45 degrees behind the airplane” or several seconds in between groups.
Experienced skydivers can make even riskier jumps, although when descents begin at higher than 15,000 feet, “the risk of hypoxia and being significantly affected by altitude” increases dramatically and divers are less able “to make effective safe decisions at critical times.” Therefore, divers who jump from 15,000 feet or higher carry supplemental oxygen.
Further, each parachute weighs around 40 pounds and the equipment is expensive. To be fully outfitted with “rig, main, reserve, ADD, altimeter, jumpsuit, helmet [and] goggles” can run between $5,900 and $9,000.
Commercial Airplane Basics
Perhaps the most popular commercial jetliner is the Boeing 737 family. Its 737-800 can carry nearly 200 people (including the crew).
Although speeds can vary slightly, the 737-800 travels at approximately 600 mph when at its cruising altitude of 35,000 feet. Cruising altitudes are assigned by air traffic controllers and are usually up to 39,000 feet, except for longer flights that may fly higher.
Individual Parachutes Won’t Improve Passenger Safety
Doing the math . . .
Passenger Training
Since four hours of training just to board a plane is unrealistic, passengers would have to read and execute detailed skydiving instructions including how to properly strap the chute on in order to benefit from the parachute. Not everyone is good at following detailed, technical instructions even when time and stress aren’t a factor.  In a situation where the plane is going down and one has only a moment to get the parachute properly strapped on (likely while keeping an oxygen mask firmly attached and perhaps also needing to keep the seat belt on to keep from being thrown about in the cabin), it’s unlikely most would be able to even get this far.

YouTube channel TodayIFoundOut has this cool video explanation. Don’t forget to Like and Subscribe their channel.

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