Kraków 2013-03-14
Outline of the history of navigation. Advances in navigation.
Flight control. 1930
We will describe the method of flight control used in the USA at the beginning of the 30s of the 20th century. At the beginning of this decade, there were over 100 small and medium-sized aviation companies operating in the USA, earning money from the transport of mail, goods and passenger transport. Their owners quickly realized that free competition required the introduction of certain legal regulations that would help introduce certain standards, and at the same time would not restrict development. They also counted on federal subsidies, which happened. At the same time, it was noticed that due to the distances, it was not possible to conduct flights only during the day. In order to be able to function realistically, flights had to be carried out also after dark. So it would be necessary to introduce some kind of orientation system during night flights, so as not to get lost. Small companies would not be able to do this on their own.
As early as May 20, 1926, the Air Commerce Act (currently FAA) was established. The first actions of the new institution were; writing down safety regulations, certification of pilots and aircraft. A system of night lighting of the take-off field was established. A system of lighting air routes (routes) was developed. (A bit like lighthouses). Initially on the most important routes, then gradually the system was introduced on secondary routes.
In the following years, the Post Office Department and the Radio Communications Department joined the cooperation. The Post Office Department, as an institution, was keenly interested in the development of commercial aviation because postal items were the first in the transport of goods. On the other hand, the Radio Communications Department was to develop an effective and cheap communication system with the crew on board the flying aircraft. The next steps of the Air Commerce Act were; designation of mandatory flight routes for commercial aviation, development of navigation standards, introduction of the first air traffic regulations for aircraft (both in the air and on the take-off field), establishment of the first flight control and management units.
In 1930, 82 transport companies merged under a joint acquisition as American Airways Inc., still being independent entities. This allowed for a more flexible market and increased safety because joint control was introduced. American Airways operated mainly on the US East Coast, the Great Lakes region, and the continental routes to Los Angeles. The most popular routes were Chicago-Detroit-Buffalo-New York and Washington-New York.
On-board radio station.
The first use of a radio station (radio telephone) probably occurred in 1915, during the Great World War. When Austrian troops in Galicia used planes with radio stations to correct artillery fire, attacking Muscovite troops.
An on-board radio station is a basic device on board an aircraft providing (wireless) communication with other aircraft, the flight control (command station) or ships at sea (ships). The first on-board radio stations mounted on aircraft appeared during the Great World War. Due to their heavy weight, they were mounted only on large transport and bomber aircraft. In another chapter, we mentioned the Farman Goliath aircraft, which was equipped with an AD-8P on-board radio station. Technical progress was so great that already in 1920, there were on-board radio stations that could be mounted on board aircraft the size of fighters. This was not done due to the end of the war and the high costs. Even pilots, considered today to be pioneers of large flights, usually did not have radio stations. In the USA in 1928, it was mandatory to have radio stations on commercial (communication) aircraft.
The development of radio technology was also significant in the Republic of Poland. In 1928, a group of Polish engineers developed a project for a telegraph and voice on-board radio station RKL/D. This design was an aviation version of the RKD divisional radio station. The RKL/D on-board radio station was mass-produced from 1930 and was part of the equipment of the Polish Army until 1939. The manufacturer was the State Communication Factory in Warsaw. The production of these radio stations is estimated at 150-200 units. These radio stations were installed on aircraft such as: Potez XXV, Breguet XIX, PWS-5, PWS-19 and Lublin R XIII. The new radio station differed from the RKD primarily in the use of a generator powered by a wind turbine. The RKL/D radio station allowed for two-way communication using keyed carrier wave telegraphy (CW), toned telegraphy (MCW) and telephony (AM) in the range of 460 – 1,200 kHz, covered continuously. In the case of cooperation with the RKD radio station on the ground, the communication range between the plane and the ground was 100 km on CW, 30 km on MCW and 25 km on AM, while between the ground and the plane – 60 km on CW and 10 km on AM.
In 1935, the production of the modern VR 27 B aviation radio station began at the Polish Philips Plant in Warsaw. The VR 27 B radio station was designed at the IV Philips 1/1/ company in the Netherlands. It was a shortwave transmitting and receiving station, adapted to work with unmodulated telegraphy (CW), toned telegraphy (MCW) and telephony (AM). It was equipped with a VZ 80/27 B transmitter and a VO l8KIV receiver. In Poland, the radio station received the designation N1LL. At the beginning of 1936, these radio stations were installed on PZL-23 Karaś and PZL-37 Łoś aircraft. During the occupation, the plants were taken over by the German plague and the production of these radio stations was resumed for the war needs of the Germans.
In the period of interest to us, the on-board radio station was more often called a radiotelephone or simply a radio. These were electronic devices built on tube systems. The radio station symbols often included the number of installed electron tubes. Radio stations required considerable knowledge from their operators. That is why, over time, a separate position for a radio operator was created on large aircraft. The radio operator had to know: Morse code, rules of correspondence, methods of encryption and codenames, rules of operation and construction of the radio station and be able to remove basic faults. The most common failures included burnout of electron tubes and power failures. On bomber aircraft, the radio operator also performed the function of the on-board gunner. Over time, subsequent radio station designs were lighter and had greater power, which translated into a greater range. The radio became the basic and often the only means of communication. It allowed obtaining important information for the safe course of the flight. Current weather forecasts were obtained, while at the same time providing information on the existing weather conditions in the air. Information about problems with the aircraft and the need to make an emergency landing was transmitted, which shortened the time needed to provide assistance. Just as the telegraph made the world smaller in the 19th century, so in aviation the radio station made the sky smaller.
At this point, it is worth mentioning the prices of aviation communication means in Poland: An aviation radio station for N2/M fighters in 1934 cost 4,000 PLN. A radio station for W24B bombers, the production of which was not undertaken, in 1934, its cost was estimated at 6,500 PLN. The most popular radio station for accompanying aviation N1L/L in 1934 cost 4,500 PLN. The same radio station in the ground version mounted on a car (trailer), marked N1L/G in 1936, cost 5,000 PLN.
Night navigation.
Due to the length of day and night, it was impossible to commercially fly only during daylight hours. Initially, only daredevils performed night flights. Among them were the French and Americans. Then they were joined by Italians and Poles. To facilitate night flights, methods of maritime navigation and the use of lanterns were used. First, airport lanterns, and soon route lanterns. The first such systems appeared in the USA and France, as well as in Poland. The French maintained night posts on postal routes in Africa and South America (in the Andes), equipped with magnesium torches or simply fires. Since 1920, the American army has maintained a system of rotating reflectors on routes connecting major airports. The first was the route between Columbus-Dayton-Cincinati (Ohio), 80 miles (128 km) long, equipped with reflectors, with a rotation period of 10 seconds. Over time, route lights began to assign the air route section number in Morse code. Due to the unreliability of the aviation technology at that time, emergency landing sites were placed near these lighthouses. These lighthouses were located 20-40 miles apart. The first air route fully equipped with navigation lights connected Chicago and Cheyenne (Wyoming) in 1923.
In the Republic of Poland, airport lighthouses were installed from 1925. From 1935, airport lighthouses were installed at the airports; Mokotów, Okęcie, Dęblin, Ławica, Rakowice, Lwów, Lublinek. In 1935, route lighthouses were placed on the Warsaw-Poznań air route. 10 of them were placed approximately every 30 km. They were metal towers about 20 meters high. The lamps had a power of 1.5 kW. In good weather, the light was visible from a distance of 100 km, which allowed the crew to see up to 3 more lights. These route lights made the Warsaw-Poznań air route available 24 hours a day. It is worth mentioning that airplanes also received strong spotlights illuminating the space in front of the airplane. At least two spotlights. Of course, such a spotlight could not illuminate the entire take-off and landing run. But it was very helpful, especially when landing. Many pilots used the principle of a double approach to landing. The first time, while flying over the take-off field, they searched for possible threats in the form of obstacles. The second time, they landed. It is not necessary to explain to anyone that landing at night at a known airport is much easier than landing at an unknown airport. The introduction of regulations and their unification throughout aviation increased the level of safety. It was mainly about the way of illuminating the take-off field, and then the runways.
Radio tracking.
The first public radio station appeared in 1920, in Pittsburgh (USA). In 1921, there were already stations broadcasting continuously in the USA and France. Since a radio station is, first of all, a transmitter with an antenna emitting electromagnetic waves. On the other end of this system, a radio receiver receiving these waves and transforming them in a loudspeaker into audible sounds. The popularity of radio grew rapidly. Even the crisis of the 1930s popularized radio even more, which, next to newspapers, became the main source of information.
At that time, it was believed that a special medium was needed to transmit electromagnetic waves in the air, which was temporarily called the ether. And so radio waves propagated in the ether. Since radio waves are in the ether, or rather electromagnetic waves, then knowing the source of radiation, one can determine the location (or at least the direction) of the aircraft in the air. This phenomenon began to be used. Certainly, armed forces used such a navigation system, then merchant shipping. This is how radio direction finding, also known as radio direction finding or radio goniometry, was born. This system uses radio direction finders (radio goniometers) for radio direction finding. The result of radio direction finding was the marking of straight lines on the map, the intersection point of which determined the location of the object being located. To determine the position, it was first necessary to adjust the radio direction finder to the frequency of the selected medium emitting the radio signal from the available information (some list of radio signals). Measure the angle, i.e. read the bearing and plot it on the map as a half-line. Do the same with the second known medium. The intersection of the half-lines indicated the position of the ship.
As early as 1906, the concept of a navigation radio beacon with a rotating beam was developed. In 1929, the first usable navigation radio beacon was built in Orfordness, England, operating on medium waves. It assisted navigation in the English Channel.
However, for civil aviation it was necessary to create a system more adapted to the needs. In the USA, the construction of a uniform aviation radio network was initiated by the establishment of the ARINC organization (Aeronautical Radio Inc., on December 2, 1929). Its tasks include maintaining and developing ground-based radio navigation and communication systems. Due to the large distances between airports, air route guidance methods were preferred in the field of navigation. In parallel with the installation of route lights, a system of medium-wave directional radio beacons LFR (Low Frequency Range) was created. Due to the significant costs of construction and maintenance, the system developed slowly.
At this point, we will mention the prices of the first navigation aids in Poland; The PG aircraft goniometer in 1937 cost PLN 1,300. The ROK/S fixed goniometer in 1938 cost PLN 2,100. The ROK movable goniometer in 1938 cost PLN 3,200.
Bolesław and Józef Adamowicz. 1934
Even before the Great World War, Bolesław and Józef Adamowicz emigrated to the USA. They made money producing cold drinks and were doing well financially. In 1928, for the first time in their lives, the brothers took a tourist flight in a small plane as passengers and from that moment on, their fascination with aviation began. For 3,400 dollars, they bought their own Waco biplane training plane (registration number NC 1868) and completed basic piloting lessons. Influenced by aviation feats around the world, including the increasingly frequent flights over the Atlantic, which had a particularly strong impact on the imagination, the brothers decided to attempt a flight over the Atlantic, following the example of Charles Lindbergh, assuming that “some Pole must conquer the ocean, because a Pole cannot be worse than an American, a Frenchman, a Dane and an Italian”. Both brothers were amateur pilots with little theoretical training.
For the flight, the brothers sold an old plane and purchased a Bellanca J300 long-distance plane, powered by a Wright engine, with an output of 200 hp, with a maximum speed of 209 km/h (registration number NR797W), for $22,000. In addition to the standard tanks with a capacity of 1,627 liters of fuel, the brothers installed two additional tanks in the fuselage for 440 gallons of gasoline, and in emergency they also took 21 gallons in canisters. The plane’s equipment included only a gyrocompass, and due to the brothers’ dwindling savings, it did not have a radio or automatic pilot. The plane received the emblem of the White Eagle painted on the fuselage and the English name “City of Warsaw” and the inscription “New York – Warsaw”. When in August 1933 the brothers flew to their planned take-off point, from New York to the small airstrip Harbour Grace in Newfoundland, the pilot they had assigned to fly the plane damaged it during landing. Nevertheless, the brothers repaired the plane and decided to attempt the flight the following year. Bolesław Adamowicz used the forced break to improve his air navigation skills and pass an exam in flights without the ground in sight, just a few days before take-off. The brothers also familiarized themselves more closely with the meteorological characteristics over the Atlantic. Nevertheless, with no radio, only a flare gun with signal cartridges, the flight was associated with an exceptionally high risk. On June 28, 1934, the brothers took off from Floyd Bennett Field near New York for the easternmost airport, Harbour Grace in Newfoundland; this time they flew under their own power and landed without problems. The next day, June 29, 1934, at 05:00, the brothers took off on a flight across the Atlantic, entering in the logbook: “June 29. Take off 5 O’Clock From Harbour Grace for Warsaw, Poland”.
Initially, the brothers flew in fairly good conditions, at an altitude of 3,000 m, but after six hours over the ocean, the temperature dropped and the plane became icy, losing maneuverability and dropping to about 1,200 m. At a lower altitude, in a warmer environment, Bolesław regained control of the plane. It was characteristic that Józef, who kept the logbook in English, after the remarks: ice.. ice.. (ice), unexpectedly entered: Boże zletujse nad nami. Flying on, the brothers encountered bad weather: a storm with dense, low-base clouds, rain and gusty winds. After several hours in a storm, the brothers managed to fly above the clouds, to an altitude of about 4,000 m. Then, after 11 hours of flight, the brothers discovered that fuel was leaking from one of the tanks. Fortunately, thanks to the emergency supply, which they had pumped into the main tanks, they had enough fuel to continue their flight. On the morning of June 30, 1934, after about 20 hours of flight, they saw the shore of Europe, but they did not know exactly where they were. As clouds and fog rolled in, the brothers flew east for another three hours, without seeing the ground, then turned around and flew in the opposite direction for an hour. Taking advantage of the improved visibility, and unable to locate any town, they landed in a random small meadow, jumping over a herd of cows – as it turned out, near the town of Fleury-sur-Orne in Normandy, France. The brothers took advantage of the hospitality of the French and met with the Polish military attaché who had arrived, and the next day after repairing the tail wheel, which had been slightly damaged during landing, the brothers took off for Paris, where their arrival had already become a sensation. After refuelling, the brothers continued their flight to Warsaw, but because they were running out of fuel, they made a mistake along the way and landed in Germany near the Polish border. Because the landing gear had to be repaired, they only took off the next day to continue their flight, but due to a mistake in course, they landed in Toruń. The brothers flew the last leg to Warsaw in the company of pilot Aleksander Onoszko, who ensured the correct navigation. At the Mokotów Airport in Warsaw, the Adamowicz family’s plane landed at around 5 p.m., with an honorary escort of Polish fighters. In total, the flight from New York to Warsaw lasted four days and eleven hours. They were the second Poles to fly across the Atlantic, after Stanisław Skarżyński (May 1933), but the first to fly across the North Atlantic. The brothers sold the plane to the Anti-Aircraft and Anti-Gas Defense League and returned to the US by ship.
De Havilland DH-84/89 Dragon. 1932
In 1932, De Havilland Aircraft Company developed a passenger plane that turned out to be a very successful design. The designer was engineer Arthur Hagg. Work on the plane had been going on since 1930. Initially, it was supposed to be a bomber. However, the growing interest in mail and passenger planes prompted the company to build such a version. There were 6 passenger seats on board. The prototype flew on November 12, 1932, and in 1934, the plane was put into serial production. By 1937, 115 planes had been built, which was a large number. Another 87 machines were built in Australia, for military and civilian needs.
That was not the end. In 1934, a modernized version was developed, which was designated DH-89. By the outbreak of World War II, over 200 units had been built. The aircraft proved to be very successful and long-lived. It was the De Havilland Dragon, and not the famous De Havilland DH-88 Comet from racing, that established British communication in the Dominions. The aircraft, built over 30 years in large numbers and versions, was used by many airlines of different countries. From Finland to New Zealand, Rhodesia and Canada. It was one of the most popular passenger aircraft. During World War II, unleashed by the German plague, it served as an auxiliary aircraft. After the war, the large Dutch airline KLM, with DH-89 aircraft, resumed operations.
T-T data of the De Havilland DH-89 Dragon aircraft: Biplane, twin-engine. Metal construction. Wingspan 14.43 m, length 10.51 m, height 3.07 m, bearing area 34.93 m2. Empty weight 1,060 kg, total weight 2,041 kg. Max speed 200 km/h, cruising speed 183 km/h, ceiling 4,420 m, range 880 km. Propulsion 2 De Havilland Gipsy Major 1 engines with 2 x 130 hp.
Curtiss T-32 Condor II. 1933
The Curtiss T-32 Condor II is an extremely well-designed passenger plane. It was created in 1930 as a bomber. Later, a transport version was also created, used by the United States Army Air Corps and other countries. In 1932, the manufacturer received an order for a passenger plane, carrying 10-15 passengers.
The Curtiss T-32 Condor II is a mixed-construction biplane, with one vertical tail and retractable landing gear. Powered by two Wright Cyclone radial engines. The first plane was flown on January 30, 1933, and production consisted of 21 planes.
The plane’s crew consisted of two pilots. They had a radio station at their disposal. The plane was equipped with a 12-person luxury passenger cabin. The innovation was to place the seats in 4 rows of three seats, in a 2 x 1 configuration. Until then, commercial aircraft had always had a 1 x 1 configuration. Thanks to this, the fuselage was much shorter and the weight of the aircraft structure per passenger was smaller. This reduced costs. On board, at the rear of the fuselage, there was a toilet and a kitchen. The seats were thickly upholstered. They had high, adjustable backrests. An individual, adjustable air supply was used for almost every passenger. The cabin was heated and ventilated. Passengers were served by a stewardess. Meals, newspapers and pillows were served. On board, passengers were allowed to smoke, so ashtrays were available. The walls of the cabin were lined with exotic varnished wood and upholstery materials. Brown was the dominant color. In 1933, this was the most luxurious aircraft deck.
In addition to the aforementioned machines, two more luxury aircraft were built. Their uniqueness was the introduction of couchettes instead of armchairs. On board, 8 couchettes were installed, for 8 passengers, who traveled sleeping. The planes were intended for night flights, on longer routes and were ordered by the airlines Eastern Air Transport and American Airways. The machines were used for 3 years.
A total of 45 planes were built. After World War II, some planes returned to civilian use and were rebuilt into passenger machines taking 15 passengers on board in 5 rows. The plane contributed to the great popularization of air travel. In 1928, airlines in the USA carried 2,651 passengers, while in 1933, it was already 120,000 people.
Written by Karol Placha Hetman