system
Given the following post, respond as if you're commenting on Reddit:
human
Why are American aircraft carriers flat, while British aircraft carriers sloped upward?

Surely there must be an internationally agreed upon method for launching an aircraft into the air from a very short distance, especially with the aircraft being so similar? What explains the disparity?
gpt
British carriers are designed for Harrier jets which can take off under their own power off a sloped deck. Their engines can be turned downward to assist takeoff.

US aircraft are launched off the carrier with a catapult that accelerates the plane from zero to flying in 2 seconds. US carriers can fly a range of aircraft using this system.