And the answer is …
… Actually there are little guardrails along the edges of aircraft carriers.
The Guardrails are six-inch high rails called scuppers that are located around most of the carrier’s deck edge.
However since space on a flight deck is very limited, oftentimes part of an aircraft and, or its stores will necessarily hang over the deck edge when parked, as seen in the below photo. Any higher railing would interfere with this.
Furthermore, there is really no need for railings since aircraft are tied down by multiple chains to the flight deck, or under close control while moving.
And if an aircraft decides to go over and off the deck, a railing would not stop it in most cases.
The scuppers are more for smaller equipment or flight deck personnel, along with nets on the carrier’s side to catch someone blown overboard.
Regarding the Flight deck edge scupper and nets, these are the metal chute between the nets they are actually meant for jettisoning ordnance overboard.
Aircraft carriers are the warships that serve as a seagoing or floating airbase.
The Aircraft carriers are usually equipped with a full-length flight deck and facilities for carrying, arming, deploying, and recovering war planes.
According to Marine Insight, the world’s biggest aircraft carriers are not mere vessels equipped to engage in warfare but in the face of never-ending territorial disputes, an aircraft carrier symbolises prestige and power for global navies.
These new ‘battleships’ have been one of the most significant assets to the warfare merchandise of all nations. Ever since their inception, the vessels have made a massive difference in the defence systems of several countries.
The biggest aircraft carriers are floating air bases equipped with a full-length flight deck capable of carrying, arming, deploying, and recovering aircraft.
Acting as the capital ship of a naval fleet on a waterfront, these vessels can carry numerous aircraft, including fighters, strike aircraft, helicopters laden with efficient weapon systems, etc.
The first aircraft carrier commissioned into the U.S. Navy was the legendary USS Langley (CV-1) which started operations on 20 March 1922.
The Langley was a converted Proteus-class collier, originally specially made as USS Jupiter (AC-3).