Which word is a synonym for congested in this sentence: An accident that occurred in the skies over the Grand Canyon in 1956 resulted in the establishment of the Federal Aviation Administration (FAA) to regulate and oversee the operation of aircraft in the skies over the United States, which were becoming quite congested.

Which word is a synonym for procedures in this sentence: The resulting structure of air traffic control has greatly increased the safety of flight in the United States, and similar air traffic control procedures are also in place over much of the rest of the wor

Which word is a synonym for rudimentary in this sentence: Rudimentary air traffic control (ATC) existed well before the Grand Canyon disaster.

Which word is a synonym for manually in this sentence: As early as the 1920s, the earliest air traffic controllers manually guided aircraft in the vicinity of the airports, using lights and flags, while beacons and flashing lights were placed along cross-country routes to establish the earliest airways.

Which word is a synonym for vicinity in this sentence: As early as the 1920s, the earliest air traffic controllers manually guided aircraft in the vicinity of the airports, using lights and flags, while beacons and flashing lights were placed along cross-country routes to establish the earliest airways.

Which word is a synonym for beacon in this sentence: As early as the 1920s, the earliest air traffic controllers manually guided aircraft in the vicinity of the airports, using lights and flags, while beacons and flashing lights were placed along cross-country routes to establish the earliest airways.

Which word is a synonym for purely in this sentence: However, this purely visual system was useless in bad weather, and, by the 1930s, radio communication was coming into use for ATC.

Which word is a synonym for metropolitan in this sentence: The first region to have something approximating today's ATC was New York City, with other major metropolitan areas following soon after.

Which word is a synonym for regulation in this sentence: It was only after the creation of the FAA that full-scale regulation of America's airspace took place, and this was fortuitous, for the advent of the jet engine suddenly resulted in a large number of very fast planes, reducing pilots' margin of error and practically demanding some set of rules to keep everyone well separated and operating safely in the air.

Which word is a synonym for fortuitous in this sentence: It was only after the creation of the FAA that full-scale regulation of America's airspace took place, and this was fortuitous, for the advent of the jet engine suddenly resulted in a large number of very fast planes, reducing pilots' margin of error and practically demanding some set of rules to keep everyone well separated and operating safely in the air.

Which word is a synonym for advent in this sentence: It was only after the creation of the FAA that full-scale regulation of America's airspace took place, and this was fortuitous, for the advent of the jet engine suddenly resulted in a large number of very fast planes, reducing pilots' margin of error and practically demanding some set of rules to keep everyone well separated and operating safely in the air.

Which word is a synonym for advent in this sentence: Many people think that ATC consists of a row of controllers sitting in front of their radar screens at the nation's airports, telling arriving and departing traffic what to do.

Which word is a synonym for realise in this sentence: This is a very incomplete part of the picture. The FAA realised that the airspace over the United States would at any time have many different kinds of planes, flying for many different purposes, in a variety of weather conditions, and the same kind of structure was needed to accommodate all of them.

Which word is a synonym for accommodate in this sentence: This is a very incomplete part of the picture. The FAA realised that the airspace over the United States would at any time have many different kinds of planes, flying for many different purposes, in a variety of weather conditions, and the same kind of structure was needed to accommodate all of them.

Which word is a synonym for virtually in this sentence: First, ATC extends over virtually the entire United States.

Which word is a synonym for regulation in this sentence: Controlled airspace is that airspace in which FAA regulations apply.

Which word is a synonym for bind in this sentence: Elsewhere, in uncontrolled airspace, pilots are bound by fewer regulations.

Which word is a synonym for recreational in this sentence: In this way, the recreational pilot who simply wishes to go flying for a while without all the restrictions imposed by the FAA has only to stay in uncontrolled airspace, below 365m, while the pilot who does want the protection afforded by ATC can easily enter the controlled airspace.

Which word is a synonym for impose in this sentence: In this way, the recreational pilot who simply wishes to go flying for a while without all the restrictions imposed by the FAA has only to stay in uncontrolled airspace, below 365m, while the pilot who does want the protection afforded by ATC can easily enter the controlled airspace.

Which word is a synonym for afford in this sentence: In this way, the recreational pilot who simply wishes to go flying for a while without all the restrictions imposed by the FAA has only to stay in uncontrolled airspace, below 365m, while the pilot who does want the protection afforded by ATC can easily enter the controlled airspace.

Which word is a synonym for meteorological in this sentence: The FAA then recognised two types of operating environments. In good meteorological conditions, flying would be permitted under Visual Flight Rules (VFR), which suggests a strong reliance on visual cues to maintain an acceptable level of safety.

Which word is a synonym for reliance in this sentence: The FAA then recognised two types of operating environments. In good meteorological conditions, flying would be permitted under Visual Flight Rules (VFR), which suggests a strong reliance on visual cues to maintain an acceptable level of safety.

Which word is a synonym for necessitated in this sentence: Poor visibility necessitated a set of Instrumental Flight Rules (IFR), under which the pilot relied on altitude and navigational information provided by the plane's instrument panel to fly safely.

Which word is a synonym for cue in this sentence: The FAA then recognised two types of operating environments. In good meteorological conditions, flying would be permitted under Visual Flight Rules (VFR), which suggests a strong reliance on visual cues to maintain an acceptable level of safety.

Which word is a synonym for devise in this sentence: On a clear day, a pilot in controlled airspace can choose a VFR or IFR flight plan, and the FAA regulations were devised in a way which accommodates both VFR and IFR operations in the same airspace.

Which word is a synonym for possess in this sentence: However, a pilot can only choose to fly IFR if they possess an instrument rating which is above and beyond the basic pilot's license that must also be held.

Which word is a synonym for designate in this sentence: Controlled airspace is divided into several different types, designated by letters of the alphabet.

Which word is a synonym for stem from in this sentence: The reason for the division of Class E and Class A airspace stems from the type of planes operating in them.

Which word is a synonym for realm in this sentence: Above 5,490m is the realm of the heavy jets, since jet engines operate more efficiently at higher altitudes.

Which word is a synonym for correspond in this sentence: These correspond roughly to small municipal, medium-sized metropolitan and major metropolitan airports respectively, and encompass an increasingly rigorous set of regulations.

Which word is a synonym for municipal in this sentence: These correspond roughly to small municipal, medium-sized metropolitan and major metropolitan airports respectively, and encompass an increasingly rigorous set of regulations.

Which word is a synonym for encompass in this sentence: These correspond roughly to small municipal, medium-sized metropolitan and major metropolitan airports respectively, and encompass an increasingly rigorous set of regulations.

Which word is a synonym for rigorous in this sentence: These correspond roughly to small municipal, medium-sized metropolitan and major metropolitan airports respectively, and encompass an increasingly rigorous set of regulations.

Which word is a synonym for explicit in this sentence: No explicit permission from ATC to enter is needed, although the pilot must continue to obey all regulations governing VFR flight.

Which word is a synonym for govern in this sentence: No explicit permission from ATC to enter is needed, although the pilot must continue to obey all regulations governing VFR flight.

Which word is a synonym for cruise in this sentence: The private pilot who cruises without permission into this airspace risks losing their license.

Which word is a synonym for license in this sentence: The private pilot who cruises without permission into this airspace risks losing their license.