HERE IS THE REPORT
I am very suspicious that this was a cyber hack and attack. If so, the attacker either got cold feet, or the pilots managed to escape the hacker. There are real life drops in altitude caused by air pockets, but 20,000 feet is unheard of.
This will become more and more common, and hackers will not be as shy as this one. The ISIS or North Korean attackers will drop the plane to the ground or water.
Soon, flying may well become unpopular because of this, and ocean liners may come back into use for international travel. If you want to travel by ship, check online for tickets on freighters. Almost all ocean going freighters have passenger accommodations for up to 36 people. Usually, service is good, but the ticket price may be higher than a liner. Also, freighter may stop at one of more ports on the way to your destination.
