Harvard Mark I
The IBM Automatic Sequence Controlled Calculator, called Mark I by Harvard University’s staff, was a general purpose electromechanical computer, used in the war effort during the last part of World War II. One of the first programs to run on the Mark I was initiated on 29 March 1944 by John von Neumann. At that time, von Neumann was working on the Manhattan project, needed to determine whether implosion was a viable choice to detonate the atomic bomb that would be used a year later; the Mark I computed and printed mathematical tables, the initial goal of British inventor Charles Babbage for his "analytical engine". The Mark I was disassembled in 1959, but portions of it are displayed in the Science Center as part of the Harvard Collection of Historical Scientific Instruments. Other sections of the original machine were transferred to the Smithsonian Institution; the original concept was presented to IBM by Howard Aiken in November 1937. After a feasibility study by IBM engineers, the company chairman Thomas Watson Sr. approved the project and its funding in February 1939.
Howard Aiken had started to look for a company to design and build his calculator in early 1937. After two rejections, he was shown a demonstration set that Charles Babbage’s son had given to Harvard University 70 years earlier; this led him to add references of the Analytical Engine to his proposal. It began computations for the U. S. Navy Bureau of Ships in May and was presented to the university on August 7, 1944; the ASCC was built from switches, rotating shafts, clutches. It used 765,000 electromechanical components and hundreds of miles of wire, comprising a volume of 816 cubic feet - 51 feet in length, 8 feet in height, 2 feet deep, it weighed about 9,445 pounds. The basic calculating units had to be synchronized and powered mechanically, so they were operated by a 50-foot drive shaft coupled to a 5 horsepower electric motor, which served as the main power source and system clock. From the IBM Archives: The Automatic Sequence Controlled Calculator was the first operating machine that could execute long computations automatically.
A project conceived by Harvard University’s Dr. Howard Aiken, the Mark I was built by IBM engineers in Endicott, N. Y. A steel frame 51 feet long and 8 feet high held the calculator, which consisted of an interlocking panel of small gears, counters and control circuits, all only a few inches in depth; the ASCC used 500 miles of wire with three million connections, 3,500 multipole relays with 35,000 contacts, 2,225 counters, 1,464 tenpole switches and tiers of 72 adding machines, each with 23 significant numbers. It was the industry’s largest electromechanical calculator; the enclosure for the Mark I was designed by futuristic American industrial designer Norman Bel Geddes. Aiken considered the elaborate casing to be a waste of resources, since computing power was in high demand during the war and the funds could have been used to build additional computer equipment; the Mark I had 60 sets of 24 switches for manual data entry and could store 72 numbers, each 23 decimal digits long. It could do 3 subtractions in a second.
A multiplication took 6 seconds, a division took 15.3 seconds, a logarithm or a trigonometric function took over one minute. The Mark I read its instructions from a 24-channel punched paper tape, it executed the current instruction and read in the next one. A separate tape could contain numbers for input. Instructions could not be executed from the storage registers; this separation of data and instructions is known as the Harvard architecture. Main sequence mechanism was unidirectional; this meant. A program loop was accomplished by loop unrolling or by joining the end of the paper tape containing the program back to the beginning of the tape. At first, conditional branching in the Mark I was performed manually. Modifications in 1946 introduced automatic program branching; the first programmers of the Mark I were computing pioneers Richard Milton Bloch, Robert Campbell, Grace Hopper. The 24 channels of the input tape were divided into three fields of eight channels; each accumulator, each set of switches, the registers associated with the input and arithmetic units were assigned a unique identifying index number.
These numbers were represented in binary on the control tape. The first field was the binary index of the result of the operation, the second was the source datum for the operation and the third field was a code for the operation to be performed. In 1928 L. J. Comrie was the first to turn IBM “punched-card equipment to scientific use: computation of astronomical tables by the method of finite differences, as envisioned by Babbage 100 years earlier for his Difference Engine”. Soon after, IBM started to modify its tabulators to facilitate this kind of computation. One of these tabulators, built in 1931, was The Columbia Difference TabulatorJohn von Neumann had a team at Los Alamos that used “modified IBM punched-card machines” to determine the effects of implosion. On 29 March 1944, he demanded
A teleprinter is an electromechanical device that can be used to send and receive typed messages through various communications channels, in both point-to-point and point-to-multipoint configurations. They were used in telegraphy, which developed in the late 1830s and 1840s as the first use of electrical engineering; the machines were adapted to provide a user interface to early mainframe computers and minicomputers, sending typed data to the computer and printing the response. Some models could be used to create punched tape for data storage and to read back such tape for local printing or transmission. Teleprinters could use a variety of different communication media; these included a simple pair of wires. A teleprinter attached to a modem could communicate through standard switched public telephone lines; this latter configuration was used to connect teleprinters to remote computers in time-sharing environments. Teleprinters have been replaced by electronic computer terminals which have a computer monitor instead of a printer.
Teleprinters are still used in the aviation industry, variations called Telecommunications Devices for the Deaf are used by the hearing impaired for typed communications over ordinary telephone lines. The teleprinter evolved through a series of inventions by a number of engineers, including Samuel Morse, Alexander Bain, Royal Earl House, David Edward Hughes, Emile Baudot, Donald Murray, Charles L. Krum, Edward Kleinschmidt and Frederick G. Creed. Teleprinters were invented in order to send and receive messages without the need for operators trained in the use of Morse code. A system of two teleprinters, with one operator trained to use a keyboard, replaced two trained Morse code operators; the teleprinter system improved message speed and delivery time, making it possible for messages to be flashed across a country with little manual intervention. There were a number of parallel developments on both sides of the Atlantic Ocean. In 1835 Samuel Morse devised a recording telegraph, Morse code was born.
Morse's instrument used a current to displace an electromagnet, which moved a marker, therefore recording the breaks in the current. Cooke & Wheatstone received a British patent covering telegraphy in 1837 and a second one in 1840 which described a type-printing telegraph with steel type fixed at the tips of petals of a rotating brass daisy-wheel, struck by an “electric hammer” to print Roman letters through carbon paper onto a moving paper tape. In 1841 Alexander Bain devised an electromagnetic printing telegraph machine, it used pulses of electricity created by rotating a dial over contact points to release and stop a type-wheel turned by weight-driven clockwork. The critical issue was to have the sending and receiving elements working synchronously. Bain attempted to achieve this using centrifugal governors to regulate the speed of the clockwork, it was patented, along with other devices, on April 21, 1841. By 1846, the Morse telegraph service was operational between Washington, D. C. and New York.
Royal Earl House patented his printing telegraph that same year. He linked two 28-key piano-style keyboards by wire; each piano key represented a letter of the alphabet and when pressed caused the corresponding letter to print at the receiving end. A "shift" key gave each main key two optional values. A 56-character typewheel at the sending end was synchronised to coincide with a similar wheel at the receiving end. If the key corresponding to a particular character was pressed at the home station, it actuated the typewheel at the distant station just as the same character moved into the printing position, in a way similar to the daisy wheel printer, it was thus an example of a synchronous data transmission system. House's equipment could transmit around 40 readable words per minute, but was difficult to manufacture in bulk; the printer could print out up to 2,000 words per hour. This invention was first put in operation and exhibited at the Mechanics Institute in New York in 1844. Landline teleprinter operations began in 1849, when a circuit was put in service between Philadelphia and New York City.
In 1855, David Edward Hughes introduced an improved machine built on the work of Royal Earl House. In less than two years, a number of small telegraph companies, including Western Union in early stages of development, united to form one large corporation – Western Union Telegraph Co. – to carry on the business of telegraphy on the Hughes system. In France, Émile Baudot designed in 1874 a system using a five-unit code, which began to be used extensively in that country from 1877; the British Post Office adopted the Baudot system for use on a simplex circuit between London and Paris in 1897, subsequently made considerable use of duplex Baudot systems on their Inland Telegraph Services. During 1901, Baudot's code was modified by Donald Murray, prompted by his development of a typewriter-like keyboard; the Murray system employed an intermediate step, a keyboard perforator, which allowed an operator to punch a paper tape, a tape transmitter for sending the message from the punched tape. At the receiving end of the line, a printing mechanism would
The Jacquard machine is a device fitted to a power loom that simplifies the process of manufacturing textiles with such complex patterns as brocade and matelassé. It was invented by Joseph Marie Jacquard in 1804; the loom was controlled by a "chain of cards". Multiple rows of holes were punched on each card, with one complete card corresponding to one row of the design. Several such paper cards white in color, can be seen in the images below. Chains, like Bouchon's earlier use of paper tape, allowed sequences of any length to be constructed, not limited by the size of a card, it is based on earlier inventions by the Frenchmen Basile Bouchon, Jean Baptiste Falcon, Jacques Vaucanson. A static display of a Jacquard loom is the centrepiece of the Musée des Tissus et des Arts décoratifs in Lyon. Live displays of a Jacquard loom are available at a few private museums around Lyon and twice a day at La Maison des Canuts, as well as at other locations around the world. Both the Jacquard process and the necessary loom attachment are named after their inventor.
This mechanism is one of the most important weaving inventions as Jacquard shedding made possible the automatic production of unlimited varieties of pattern weaving. The term "Jacquard" is not specific or limited to any particular loom, but rather refers to the added control mechanism that automates the patterning; the process can be used for patterned knitwear and machine-knitted textiles, such as jerseys. This use of replaceable punched cards to control a sequence of operations is considered an important step in the history of computing hardware. Traditionally, figured designs were made on a drawloom; the heddles with warp ends to be pulled up were manually selected by a second operator, the draw boy, not the weaver. The work was slow and labour-intensive, the complexity of the pattern was limited by practical factors. An improvement of the draw loom took place in 1725, when Basile Bouchon introduced the principle of applying a perforated band of paper. A continuous roll of paper was punched by hand, in sections, each of which represented one lash or tread, the length of the roll was determined by the number of shots in each repeat of pattern.
The Jacquard machine evolved from this approach. Joseph Marie Jacquard saw that a mechanism could be developed for the production of sophisticated patterns, he combined mechanical elements of other inventors, but innovated. His machine was similar to Vaucanson's arrangement, but he made use of Jean-Baptiste Falcon's individual paste board cards and his square prism: he is credited with having perforated each of its four sides, replacing Vaucanson's perforated "barrel". Jacquard's machine contained eight rows of needles and uprights, where Vaucanson had double row, a modification that enabled him to increase the figuring capacity of the machine. In his first machine, he supported the harness by knotted cords, which he elevated by a single trap board. One of the chief advantages claimed for the Jacquard machine was that unlike previous damask-weaving machines, in which the figuring shed was drawn once for every four shots, with the new apparatus, it could be drawn on every shot, thus producing a fabric with greater definition of outline.
Jacquard's invention had a deep influence on Charles Babbage. In that respect, he is viewed by some authors as a precursor of modern computing science. On the diagram to the right, the cards are fastened into a continuous chain which passes over a square box. At each quarter rotation a new card is presented to the Jacquard head; the box swings from presses against the control rods. Where there is a hole the rod passes through the card and is unmoved whereas if the hole is not punched the rod is pushed to the left; each rod acts upon a hook. When the rod is pushed in the hook moves out of position to the left, a rod, not pushed in leaves its hook in place. A beam rises under the hooks and those hooks in the rest location are raised; each hook can have multiple cords. The cords are attached to their heddle and a return weight; the heddles raise the warp to create the shed. A loom with a 400 hook head might have four threads connected to each hook, resulting in a fabric, 1600 warp ends wide with four repeats of the weave going across.
The term "Jacquard loom" is somewhat inaccurate. It is the "Jacquard head" that adapts to a great many dobby looms that allow the weaving machine to create the intricate patterns seen in Jacquard weaving. Jacquard looms, although common in the textile industry, are not as ubiquitous as dobby looms which are faster and much cheaper to operate. However, unlike jacquard looms, they are not capable of producing so many different weaves from one warp. Modern jacquard looms are controlled by computers in place of the original punched cards, can have thousands of hooks; the threading of a Jacquard loom is so labor-intensive. Subsequent warps are tied into the existing warp with the help of a knotting robot which ties each new thread on individually. For a small loom with only a few thousand warp ends the process of re-threading can take days; the Jacquard machines were mechanical, the fabric design was stored in a series of punched cards which were joined to form a continuous chain. The Jacquards were small and only independently controlled a few warp ends
A player piano is a self-playing piano, containing a pneumatic or electro-mechanical mechanism that operates the piano action via pre-programmed music recorded on perforated paper, or in rare instances, metallic rolls, with more modern implementations using MIDI. The rise of the player piano grew with the rise of the mass-produced piano for the home in the late 19th and early 20th century. Sales peaked in 1924 declined as the improvement in phonograph recordings due to electrical recording methods developed in the mid-1920s; the advent of electrical amplification in home music reproduction via radio in the same period helped cause their eventual decline in popularity, the stock market crash of 1929 wiped out production. The idea of automatic musical devices can be traced back many centuries, the use of pinned barrels to operate percussion mechanisms was perfected long before the invention of the piano; these devices were extended to operate musical boxes, which contain a set of tuned metal teeth plucked by the player mechanism.
An early musical instrument to be automated was the organ, comparatively easy to operate automatically. The power for the notes is provided by air from a bellows system, the organist or player device only has to operate a valve to control the available air; the playing task is ideally performed by a pinned barrel, the art of barrel organs was well advanced by the mid-18th century. The piano is a complex instrument, requiring each note to be struck with a different force to control the dynamics of the performance; the entire force required to sound the note must be given by the performer hitting the keys. It proved to be difficult for a player device to combine a variable percussive force and a controlled note duration. Barrels do not provide a percussive force, but a gentle switching motion. Early barrel pianos moved the hammer back and forwards continuously as the operator turned the handle, but the hammers did not strike the strings until moved forwards by a pin in the barrel; the hammers hit until the pin was removed.
This played the note, but with a tremolo action quite unlike a pianist. The development of the player piano was the gradual overcoming of the various difficulties of controlled percussive striking and note duration; the earliest practical piano playing device was the Forneaux Pianista, which used compressed air to inflate a bellows when the barrel pin opened a valve. This bellows so played the note; the acceleration of developments leading to the pneumatic'player' device started in the 1840s and began to reach some recognizable device in the 1870s. The start of the player period can be seen as the Centennial Exposition of 1876 in Philadelphia, USA. At this exhibition were a number of automatic player devices, including the Pianista, that contained the elements which would lead to the player; the earliest description of a piano playing device using perforated paper rolls was Claude Seytre's French patent of 1842. The concept was sound, but the device described was impractical in the way it read the roll and operated the piano.
In 1847, Alexander Bain described a device that used a paper roll as a'travelling valve' that allowed air to flow through the reeds of a reed organ. Simple reed and pipe organs using this sort of system are still being produced. However, the air flow is not sufficient to drive a piano mechanism. In 1848 Charles Dawson of England described a more complex travelling valve device which added little to Bain's. Hunt & Bradish of the US, 1849, used a roll read by sprung fingers, the springs being strong enough to operate the piano mechanism directly; this device applied the entire playing strength to the paper, so would have shredded it and the device would have had to be as wide as the piano keyboard. In 1851, England, submitted a patent that recognized the need to remove the playing force from the paper, using light springs to read the roll and activate a more robust device which plays the note—a mechanical amplifier; the first device to address the practical requirement of operating a piano mechanism was Forneaux's, of 1863.
This recognized. It used a traditional barrel, but tripped a pneumatic device that inflated bellows to operate the note. In 1871 a perforated cardboard book was substituted for the barrel, but it was still read using sprung fingers; this device entered manufacture, is regarded as the first practical player device. It was exhibited in Philadelphia in 1876. Van Dusen's American patent of 1867 was the first to describe a pneumatic striker operated by a roll, it was based on the work of John McTammany. A leap in thought occurred in the 1873 patent of the Schmoele brothers, they described a'double valve' system that acted as a pneumatic amplifier, reading the roll electrically and operating the pneumatics with an electromagnet. They exhibited at Philadelphia. With some modification, pneumatic reading of the roll, this would become the final player piano some 20 years although the Schmoele brothers never benefited from it. In 1876, John McTammany exhibited a working player in Philadelphia that used a paper roll read using sprung fingers whose slight movement triggered a mechanical player device.
This operated a reed organ. McTammany had been experimenting since the mid-1860s, went on to be one of the key names in the early player industry, he claimed to be the inventor of the'player', but not the'player piano'—an important distinction. As of 1876, in Philadelphia, three working devices were exhibited that between them contained all the components that the final player pi
Colossus was a set of computers developed by British codebreakers in the years 1943–1945 to help in the cryptanalysis of the Lorenz cipher. Colossus used thermionic valves to perform counting operations. Colossus is thus regarded as the world's first programmable, digital computer, although it was programmed by switches and plugs and not by a stored program. Colossus was designed by research telephone engineer Tommy Flowers to solve a problem posed by mathematician Max Newman at the Government Code and Cypher School at Bletchley Park. Alan Turing's use of probability in cryptanalysis contributed to its design, it has sometimes been erroneously stated that Turing designed Colossus to aid the cryptanalysis of the Enigma. Turing's machine that helped decode; the prototype, Colossus Mark 1, was shown to be working in December 1943 and was in use at Bletchley Park by early 1944. An improved Colossus Mark 2 that used shift registers to quintuple the processing speed, first worked on 1 June 1944, just in time for the Normandy landings on D-Day.
Ten Colossi were in use by the end of the war and an eleventh was being commissioned. Bletchley Park's use of these machines allowed the Allies to obtain a vast amount of high-level military intelligence from intercepted radiotelegraphy messages between the German High Command and their army commands throughout occupied Europe; the existence of the Colossus machines was kept secret until the mid-1970s. This deprived most of those involved with Colossus of the credit for pioneering electronic digital computing during their lifetimes. A functioning rebuild of a Mark 2 Colossus was completed in 2008 by some volunteers; the Colossus computers were used to help decipher intercepted radio teleprinter messages, encrypted using an unknown device. Intelligence information revealed that the Germans called the wireless teleprinter transmission systems "Sägefisch"; this led the British to call encrypted German teleprinter traffic "Fish", the unknown machine and its intercepted messages "Tunny". Before the Germans increased the security of their operating procedures, British cryptanalysts diagnosed how the unseen machine functioned and built an imitation of it called "British Tunny".
It was deduced that the machine had twelve wheels and used a Vernam ciphering technique on message characters in the standard 5-bit ITA2 telegraph code. It did this by combining the plaintext characters with a stream of key characters using the XOR Boolean function to produce the ciphertext. In August 1941, a blunder by German operators led to the transmission of two versions of the same message with identical machine settings; these were worked on at Bletchley Park. First, John Tiltman, a talented GC&CS cryptanalyst, derived a key stream of 4000 characters. Bill Tutte, a newly arrived member of the Research Section, used this key stream to work out the logical structure of the Lorenz machine, he deduced that the twelve wheels consisted of two groups of five, which he named the χ and ψ wheels, the remaining two he called μ or "motor" wheels. The chi wheels stepped with each letter, encrypted, while the psi wheels stepped irregularly, under the control of the motor wheels. With a sufficiently random key stream, a Vernam cipher removes the natural language property of a plaintext message of having an uneven frequency distribution of the different characters, to produce a uniform distribution in the ciphertext.
The Tunny machine did this well. However, the cryptanalysts worked out that by examining the frequency distribution of the character-to-character changes in the ciphertext, instead of the plain characters, there was a departure from uniformity which provided a way into the system; this was achieved by "differencing" in which each character was XOR-ed with its successor. After Germany surrendered, allied forces captured a Tunny machine and discovered that it was the electromechanical Lorenz SZ in-line cipher machine. In order to decrypt the transmitted messages, two tasks had to be performed; the first was "wheel breaking", the discovery of the cam patterns for all the wheels. These patterns were set up on the Lorenz machine and used for a fixed period of time for a succession of different messages; each transmission, which contained more than one message, was enciphered with a different start position of the wheels. Alan Turing invented a method of wheel-breaking. Turing's technique was further developed into "Rectangling", for which Colossus could produce tables for manual analysis.
Colossi 2, 4, 6, 7 and 9 had a "gadget" to aid this process. The second task was "wheel setting", which worked out the start positions of the wheels for a particular message, could only be attempted once the cam patterns were known, it was this task for which Colossus was designed. To discover the start position of the chi wheels for a message, Colossus compared two character streams, counting statistics from the evaluation of programmable Boolean functions; the two streams were the ciphertext, read at high speed from a paper tape, the key stream, generated internally, in a simulation of the unknown German machine. After a succession of different Colossus runs to discover the chi-wheel settings, they were checked by examining the frequency distribution of the characters in processed ciphertext. Colossus prod
Chad refers to fragments sometimes created when holes are made in a paper, card or similar synthetic materials, such as computer punched tape or punched cards. "Chad" has been used both as a countable noun. In the 2000 United States presidential election, many Florida votes used Votomatic-style punched card ballots where incompletely punched holes resulted in punched chads: either a "hanging chad", where one or more corners were still attached, or a "fat chad" or "pregnant chad", where all corners were still attached, but an indentation appears to have been made; these votes were not counted by the tabulating machines. The aftermath of the controversy caused the rapid discontinuance of punch card ballots in the United States. Chad is sometimes used as confetti; the origin of the term chad is uncertain. Patent documents from the 1930s and 1940s show the word "chad" in reference to punched tape used in telegraphy; these patents sometimes include synonyms such as "chaff" and "chips". A patent filing in 1930 included a "receptacle or chad box... to receive the chips cut from the edge of the tape."
A 1938 patent filing included a "chaff or chad chute" to collect the waste fragments. Both patents were assigned to Teletype Corporation; the plural chads is attested from about 1939, along with chadless, meaning "without chad". Clear definitions for both terms are offered by Walter Bacon in a patent application filed in 1940 assigned to Bell Telephone Laboratories: "... In making these perforations, the perforator cuts small round pieces of paper, known in the art as chads, out of the tape; these chads are objectionable... Chadless tape is prepared by feeding blank tape through a device which will not punch a complete circle in the tape but, will only cut three-quarters of the circumference of a circle... thereby leaving a movable, or hinged, lid of paper in the tape."In the New Hacker's Dictionary, two unattributed and humorous derivations for "chad" are offered, a back-formation from a personal name "Chadless" and an acronym for "Card Hole Aggregate Debris". Other etymologies claim derivation from the Scottish name for river gravel, chad, or the British slang for louse, chat.
When a chad is not detached, it is described by various terms corresponding to the level of modification from the unpunched state. The distinctions are of importance in counting cards used in voting; the following terms apply when describing a four-cornered chad: Hanging chads are attached to the ballot at only one corner. Swinging chads are attached to the ballot at two corners. Tri-chads are attached to the ballot at three corners. Pregnant or dimpled chads are attached to the ballot at all four corners, but bear an indentation indicating the voter may have intended to mark the ballot. Bit bucket Bush v. Gore, "two-corner chad rule" Chinese paper cutting Confetti, recycling chad for celebratory use. Keypunch—Card punch Papel Picado Paper tape Punched card Recount Teleprinter—Teletype United States presidential election in Florida, 2000 Snopes – Origin of'Chad' Word Detective on chad BBC News on chad Macmillan English Dictionary on chad Jargon file entry
Federal Aviation Administration
The Federal Aviation Administration is a governmental body of the United States with powers to regulate all aspects of civil aviation in that nation as well as over its surrounding international waters. Its powers include the construction and operation of airports, air traffic management, the certification of personnel and aircraft, the protection of U. S. assets during the launch or re-entry of commercial space vehicles. Powers over neighboring international waters were delegated to the FAA by authority of the International Civil Aviation Organization. Created in August 1958, the FAA replaced the former Civil Aeronautics Administration and became an agency within the US Department of Transportation; the FAA's roles include: Regulating U. S. commercial space transportation Regulating air navigation facilities' geometric and flight inspection standards Encouraging and developing civil aeronautics, including new aviation technology Issuing, suspending, or revoking pilot certificates Regulating civil aviation to promote transportation safety in the United States through local offices called Flight Standards District Offices Developing and operating a system of air traffic control and navigation for both civil and military aircraft Researching and developing the National Airspace System and civil aeronautics Developing and carrying out programs to control aircraft noise and other environmental effects of civil aviation The FAA is divided into four "lines of business".
Each LOB has a specific role within the FAA. Airports: plans and develops projects involving airports, overseeing their construction and operations. Ensures compliance with federal regulations. Air Traffic Organization: primary duty is to safely and efficiently move air traffic within the National Airspace System. ATO employees manage air traffic facilities including Airport Traffic Control Towers and Terminal Radar Approach Control Facilities. See Airway Operational Support. Aviation Safety: Responsible for aeronautical certification of personnel and aircraft, including pilots and mechanics. Commercial Space Transportation: ensures protection of U. S. assets during the launch or reentry of commercial space vehicles. The FAA is headquartered in Washington, D. C. as well as the William J. Hughes Technical Center in Atlantic City, New Jersey, the Mike Monroney Aeronautical Center in Oklahoma City and its nine regional offices: Alaskan Region – Anchorage, Alaska Northwest Mountain – Seattle, Washington Western Pacific – Los Angeles, California Southwest – Fort Worth, Texas Central – Kansas City, Missouri Great Lakes – Chicago, Illinois Southern – Atlanta, Georgia Eastern – New York, New York New England – Boston, Massachusetts The Air Commerce Act of May 20, 1926, is the cornerstone of the federal government's regulation of civil aviation.
This landmark legislation was passed at the urging of the aviation industry, whose leaders believed the airplane could not reach its full commercial potential without federal action to improve and maintain safety standards. The Act charged the Secretary of Commerce with fostering air commerce and enforcing air traffic rules, licensing pilots, certifying aircraft, establishing airways, operating and maintaining aids to air navigation; the newly created Aeronautics Branch, operating under the Department of Commerce assumed primary responsibility for aviation oversight. In fulfilling its civil aviation responsibilities, the Department of Commerce concentrated on such functions as safety regulations and the certification of pilots and aircraft, it took over the building and operation of the nation's system of lighted airways, a task initiated by the Post Office Department. The Department of Commerce improved aeronautical radio communications—before the founding of the Federal Communications Commission in 1934, which handles most such matters today—and introduced radio beacons as an effective aid to air navigation.
The Aeronautics Branch was renamed the Bureau of Air Commerce in 1934 to reflect its enhanced status within the Department. As commercial flying increased, the Bureau encouraged a group of airlines to establish the first three centers for providing air traffic control along the airways. In 1936, the Bureau itself began to expand the ATC system; the pioneer air traffic controllers used maps and mental calculations to ensure the safe separation of aircraft traveling along designated routes between cities. In 1938, the Civil Aeronautics Act transferred the federal civil aviation responsibilities from the Commerce Department to a new independent agency, the Civil Aeronautics Authority; the legislation expanded the government's role by giving the CAA the authority and the power to regulate airline fares and to determine the routes that air carriers would serve. President Franklin D. Roosevelt split the authority into two agencies in 1940: the Civil Aeronautics Administration and the Civil Aeronautics Board.
CAA was responsible for ATC, airman and aircraft certification, safety enforcement, airway development. CAB was entrusted with safety regulation, accident investigation, economic regulation of the airlines; the CAA was part of the Department of Commerce. The CAB was an independent federal agency. On the eve of America's entry into World War II, CAA began to extend its ATC responsibilities to takeoff and landing operations at airports; this expanded role became permanent after the war. The application of radar to ATC helped controllers in their drive to keep abreast of the postwar boom in commercial air transportation. In 1946, Congress gave CAA the added task of administering the federal-aid airport program, the first peacetime program of financial assistance aimed exclusivel