Tupolev ANT-25
Encyclopedia
The Tupolev ANT-25 was a Soviet
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....

 long-range experimental aircraft
Experimental aircraft
An experimental aircraft is an aircraft that has not yet been fully proven in flight. Often, this implies that new aerospace technologies are being tested on the aircraft, though the label is more broad....

 which was also tried as a bomber. First constructed in 1933
1933 in aviation
This is a list of aviation-related events from 1933:- Events :* The United States Coast Guard requests authorization to construct its first cutters with a capability of carrying aircraft.* Tokyo conducts it first blackout exercise....

, it was used by the Soviet Union for a number of record-breaking flights.

History and records

The ANT-25 was designed as the result of a recommendation by Kliment Voroshilov
Kliment Voroshilov
Kliment Yefremovich Voroshilov , popularly known as Klim Voroshilov was a Soviet military officer, politician, and statesman...

 to the Revolutionary Military Council
Revolutionary Military Council
Revolutionary Military Council of the Republic or Revvoyensoviet Revolutionary Military Council of the Republic or Revvoyensoviet Revolutionary Military Council of the Republic or Revvoyensoviet (Революционный Военный Совет, Revolyutsionny Voyenny Sovyet; Реввоенсовет, Revvoyensovyet; also...

 Revvoyensovyet on 7 December 1931, to build an aircraft for long range flights.

The aircraft was designed by the brigade of the Experimental Aircraft Design Department of TsAGI led by Pavel Sukhoi
Pavel Sukhoi
Pavel Osipovich Sukhoi was a Soviet aerospace engineer. He designed the Sukhoi military aircraft and founded the Sukhoi Design Bureau. -Biography:...

 under the overall supervision of Andrei Tupolev
Andrei Tupolev
Andrei Nikolayevich Tupolev was a pioneering Soviet aircraft designer.During his career, he designed and oversaw the design of more than 100 types of aircraft, some of which set 78 world records...

. The first prototype, designated Experimental airplane RD-1, (also designated TsAGI
TsAGI
TsAGI is a transliteration of the Russian abbreviation for Центра́льный аэрогидродинами́ческий институ́т or "Tsentralniy Aerogidrodinamicheskiy Institut", the Central Aerohydrodynamic Institute....

-25, ANT-25), RD standing for Rekord Dalnosty, i.e. "Range Record") made its maiden flight on 22 June 1933, piloted by Mikhail Gromov
Mikhail Gromov (aviator)
Mikhail Mikhaylovich Gromov was a famous Russian aviator and Hero of the Soviet Union.On 12-14 July 1937, Mikhail Gromov, A. B. Yumashev and S. A...

 and used a direct drive M-34
Mikulin AM-34
The Mikulin AM-34 was the Soviet Union’s first indigenous mass-produced, liquid-cooled, aircraft engine. Its initial development was troubled, but it eventually became one of the most successful Soviet aircraft engines of the 1930s...

 engine.

The first crew, Gromov, Filin and Spirin, began with a long range test flight in September 1934 on the second prototype, the RD-2. The RD-2 used a geared M-34R engine, which substantially increased its range. They spent 75 hours in the air, covering 12411 kilometres (7,711.9 mi) in a single trip, (Moscow
Moscow
Moscow is the capital, the most populous city, and the most populous federal subject of Russia. The city is a major political, economic, cultural, scientific, religious, financial, educational, and transportation centre of Russia and the continent...

 — Ryazan
Ryazan
Ryazan is a city and the administrative center of Ryazan Oblast, Russia. It is located on the Oka River southeast of Moscow. Population: The strategic bomber base Dyagilevo is just west of the city, and the air base of Alexandrovo is to the southeast as is the Ryazan Turlatovo Airport...

 — Tula
Tula, Russia
Tula is an industrial city and the administrative center of Tula Oblast, Russia. It is located south of Moscow, on the Upa River. Population: -History:...

 — Dnepropetrovsk — Kharkov). The aircraft was unable to return to Moscow due to a fuel shortage. Gromov was made a Hero of the Soviet Union
Hero of the Soviet Union
The title Hero of the Soviet Union was the highest distinction in the Soviet Union, awarded personally or collectively for heroic feats in service to the Soviet state and society.-Overview:...

. The flight was not recognised as a world record as it could not complete the circuit to Moscow, so could not claim the closed circuit record, while the direct distance between Moscow and Kharkov was too short for the distance in a straight line record.

Gromov and Yumashev decided to make their next long-range flight an attempt at the straight-line record. They wanted to fly the traditional long-range route via Africa and the Atlantic Ocean to South America. A crewman, Sigizmund Levanevsky
Sigizmund Levanevsky
Sigizmund Aleksandrovich Levanevsky was a Soviet aircraft pilot of Polish origin and a Hero of the Soviet Union .-Life and career:...

, on studying some maps, suggested they fly in a completely different direction – to the north. Polar aviators were extremely popular at that time, his plan was considered plausible. The flight was cancelled in the spring of 1935 when he fell seriously ill.

The next long range flight planned, was from Moscow to the USA via the North Pole. A sloping concrete runway 4 kilometres (2.5 mi) in length, was built at Schelkovo air-base near Moscow. In the early morning of 3 August 1935, Levanevsky, Baydukov and Levchenko climbed aboard their RD and took to the air. For the first 50 kilometres (31.1 mi), the aircraft ascended to only 500 metres (1,640.4 ft). They then steadily increased their altitude to 5000 metres (16,404.2 ft), maintaining an average speed of 165 kilometres per hour (102.5 mph). After approximately 2000 kilometres (1,242.7 mi), an oil leak was discovered but the aircraft was able to make an emergency landing at Krechevits near Novgorod. Levanevskiy was called to a Politburo meeting, where he blamed Tupolev, declaring that his single-engined ANT-25 was under-powered. It seemed to be the end for the aircraft.

His second pilot Georgy Baydukov, who was also an aviation engineer, disagreed and proposed Valery Chkalov for a second attempt. Chkalov was at first sceptical about his selection, as he was a fighter pilot with little navigational knowledge. Baydukov briefed Chkalov on the finer points of flying the ANT-25 and proposed Alexander Belyakov
Alexander Vasilyevich Belyakov
Alexander Vasilyevich Belyakov was a Soviet flight navigator who, together with command pilot Valery Chkalov and co-pilot Georgy Baydukov, set a record for the longest uninterrupted flight in 1936 and made the first non-stop flight across the North Pole, flying from Moscow to Vancouver,...

, who was the chief instructor of their flight academy, as their third crewman. Chkalov's authority was enough to convince Stalin.

In July 1936, the record was broken by Chkalov
Valery Chkalov
Valery Pavlovich Chkalov was a Russian aircraft test pilot and a Hero of the Soviet Union .-Early life:...

, Georgy Baydukov and Belyakov flying the same aircraft from Moscow to the Far East (Stalin's Route) in 56 hours 20 minutes; a distance of 9374 kilometres (5,824.7 mi). They passed Franz Josef Land
Franz Josef Land
Franz Josef Land, Franz Joseph Land, or Francis Joseph's Land is an archipelago located in the far north of Russia. It is found in the Arctic Ocean north of Novaya Zemlya and east of Svalbard, and is administered by Arkhangelsk Oblast. Franz Josef Land consists of 191 ice-covered islands with a...

 — Severnaya Zemlya
Severnaya Zemlya
Severnaya Zemlya is an archipelago in the Russian high Arctic at around . It is located off mainland Siberia's Taymyr Peninsula across the Vilkitsky Strait...

 — Tiksi
Tiksi
Tiksi is an urban locality and the administrative center of Bulunsky District of the Sakha Republic, Russia, situated on the Arctic Ocean coast. Population: It is one of the principal ports for accessing the Laptev Sea...

 — Yakutia — Petropavlovsk-Kamchatsky
Petropavlovsk-Kamchatsky
Petropavlovsk-Kamchatsky is the main city and the administrative, industrial, scientific, and cultural center of Kamchatka Krai, Russia. Population: .-History:It was founded by Danish navigator Vitus Bering, in the service of the Russian Navy...

 — Khabarovsk
Khabarovsk
Khabarovsk is the largest city and the administrative center of Khabarovsk Krai, Russia. It is located some from the Chinese border. It is the second largest city in the Russian Far East, after Vladivostok. The city became the administrative center of the Far Eastern Federal District of Russia...

 — Okhotsk Sea and landed on a beach at Udd Island (now called Chkalov Island), near the Amur River.

The next day, Pravda
Pravda
Pravda was a leading newspaper of the Soviet Union and an official organ of the Central Committee of the Communist Party between 1912 and 1991....

 newspaper published a leading article "Glory to Stalin's Sokols
Sokol (disambiguation)
Sokol is a Pan-Slavic physical education movement, with origins in the Czech lands.Sokol, Sokół, or Szokol meaning falcon in Slavic languages, may also refer to:- Other uses :...

!" («Слава сталинским соколам!»). A wooden runway was constructed on Udd island and on 2 August, the ANT-25 departed for Moscow. The trip back lasted a week with stops at Khabarovsk
Khabarovsk
Khabarovsk is the largest city and the administrative center of Khabarovsk Krai, Russia. It is located some from the Chinese border. It is the second largest city in the Russian Far East, after Vladivostok. The city became the administrative center of the Far Eastern Federal District of Russia...

, Chita, Krasnoyarsk
Krasnoyarsk
Krasnoyarsk is a city and the administrative center of Krasnoyarsk Krai, Russia, located on the Yenisei River. It is the third largest city in Siberia, with the population of 973,891. Krasnoyarsk is an important junction of the Trans-Siberian Railway and one of Russia's largest producers of...

 and Omsk
Omsk
-History:The wooden fort of Omsk was erected in 1716 to protect the expanding Russian frontier along the Ishim and the Irtysh rivers against the Kyrgyz nomads of the Steppes...

 with a grand welcome at each. Chkalov's trio became Heroes of the Soviet Union. Two islands nearby were renamed after Baydukov and Belyakov.

Chkalov's achievement became world-famous, however, the Politburo still wanted the publicity of a direct flight. Gromov was ordered to fly to Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...

 on 14 August 1936 in a second ANT-25, but as he prepared for the start on 25 September, Brazilian officials denied access to the Soviet plane and the flight was cancelled.

Both Chkalov's and Gromov's crews were now destined to fly north from Moscow to San Francisco. Over 18–20 June 1937 - the same crew of Valery Chkalov, co-pilot Georgy Baydukov and navigator A. Belyakov made a non-stop flight from Moscow to Portland
Portland, Oregon
Portland is a city located in the Pacific Northwest, near the confluence of the Willamette and Columbia rivers in the U.S. state of Oregon. As of the 2010 Census, it had a population of 583,776, making it the 29th most populous city in the United States...

, United States, in bad weather. At the 60 hour point they passed Seattle, after two more hours they passed Portland lighthouse on the Columbia River
Columbia River
The Columbia River is the largest river in the Pacific Northwest region of North America. The river rises in the Rocky Mountains of British Columbia, Canada, flows northwest and then south into the U.S. state of Washington, then turns west to form most of the border between Washington and the state...

 and headed deeper into US territory. Over the city of Eugene
Eugene, Oregon
Eugene is the second largest city in the U.S. state of Oregon and the seat of Lane County. It is located at the south end of the Willamette Valley, at the confluence of the McKenzie and Willamette rivers, about east of the Oregon Coast.As of the 2010 U.S...

 they found they were short of fuel and turned back for the military airbase at Vancouver
Vancouver, Washington
Vancouver is a city on the north bank of the Columbia River in the U.S. state of Washington. Incorporated in 1857, it is the fourth largest city in the state with a 2010 census population of 161,791 as of April 1, 2010...

, landing at Pearson Airfield. (by the other sources – Barak Airfield). The 9130 kilometres (5,673.1 mi) trip took 63 hours and 25 minutes. In 1975, an obelisk was erected on the airfield to commemorate this event.

Another widely publicized feat was the Moscow - San Jacinto
San Jacinto, California
San Jacinto is a city in Riverside County, California, U.S.A. It was named after Saint Hyacinth and is located at the north end of the San Jacinto Valley, with Hemet to its south. The mountains associated with the valley are the San Jacinto Mountains. The population was 44,199 at the 2010...

 non-stop flight in a backup aircraft just three weeks after Chkalov's. This jourmey, via the North Pole, covered 11500 kilometres (7,145.8 mi) and ended in a dairy pasture outside of San Jacinto, California after they had encountered fog conditions in San Diego and as far inland as March Air Force base in Riverside. The landing site is marked by California State Historical Landmark Number 989. The crew, still composed of Gromov, Yumashev, and Danilin, flew for 62 hours and 17 minutes between 12 and 14 July 1937. After landing, the aircraft still had sufficient fuel for approximately 1500 kilometres (932.1 mi), enough to reach Panama
Panama
Panama , officially the Republic of Panama , is the southernmost country of Central America. Situated on the isthmus connecting North and South America, it is bordered by Costa Rica to the northwest, Colombia to the southeast, the Caribbean Sea to the north and the Pacific Ocean to the south. The...

. This would have involved crossing the Mexican border without the permission of FAI
Fédération Aéronautique Internationale
The Fédération Aéronautique Internationale is the world governing body for air sports and aeronautics and astronautics world records. Its head office is in Lausanne, Switzerland. This includes man-carrying aerospace vehicles from balloons to spacecraft, and unmanned aerial vehicles...

 sporting officials.

Gromov became an unofficial Soviet Pilot No. 1, Chkalov remained the favourite pilot of the Soviet people. Joy at the achievements were tempered by Levanevsky crashing on the same route in a brand-new 4-engined DB-A.

The record set by the Soviets was broken by two British Vickers Wellesley
Vickers Wellesley
The Vickers Wellesley was a British 1930s light bomber built by Vickers-Armstrongs at Brooklands near Weybridge, Surrey, for the Royal Air Force...

 bombers which flew from Egypt to Australia in November 1938; a distance of 11523.9 kilometres (7,160.6 mi). The USSR did not continue the race, aviation design bureau works stalled due to repression
Political repression
Political repression is the persecution of an individual or group for political reasons, particularly for the purpose of restricting or preventing their ability to take political life of society....

. Tupolev was jailed, Gromov was also on the brink of arrest. Chkalov mysteriously crashed while testing a new fighter on 15 December 1938.

After Chkalov's death, Usachoyv, the Chief of the Aviation Industry Directorate Belyaikin and the director of the plant where Chkalov's machine had been built, and Tomashevich, the designer, all came under suspicion due to sabotage
Sabotage
Sabotage is a deliberate action aimed at weakening another entity through subversion, obstruction, disruption, or destruction. In a workplace setting, sabotage is the conscious withdrawal of efficiency generally directed at causing some change in workplace conditions. One who engages in sabotage is...

. Nikolai Polikarpov escaped arrest.

Technology

The main reason for the aircraft's success was due to the wing design. The wide-span wings gave the aircraft good range and fuel-efficiency, they could also house large fuel tanks. The proportion of the wingspan
Wingspan
The wingspan of an airplane or a bird, is the distance from one wingtip to the other wingtip. For example, the Boeing 777 has a wingspan of about ; and a Wandering Albatross caught in 1965 had a wingspan of , the official record for a living bird.The term wingspan, more technically extent, is...

 to the chord
Chord (aircraft)
In aeronautics, chord refers to the imaginary straight line joining the trailing edge and the center of curvature of the leading edge of the cross-section of an airfoil...

 was more than a factor of 13. Fuel was 52% of the take-off weight
Maximum Take-Off Weight
The Maximum Takeoff Weight or Maximum Takeoff Mass of an aircraft is the maximum weight at which the pilot of the aircraft is allowed to attempt to take off, due to structural or other limits. The analogous term for rockets is Gross Lift-Off Mass, or GLOW...

, the tanks had been moved from the fuselage - this allowed the wings to tension as fuel weight opposed the aerodynamics forces.

Research was conducted into special forms of vibration of the aircraft because of the longer wings and at a speed greater than some critical point - the so-called flutter effect.

To stay afloat after ditching, the ANT-25 used air-filled bags made of rubberised fabric.

According to the archives, the idea of a military variant of the RD first came to the engineer Zhemchuzhin of the 7th sector of the Soviet Air Force Scientific Research Institute. Its slow speed, low altitude, poor maneuverability and large wingspan made it a perfect target for fighters and anti-aircraft guns.

Only two aircraft were manufactured, which were followed by the Tupolev DB-1
Tupolev DB-1
-See also:...

. In 1934 the aviation plant in Voronezh
Voronezh
Voronezh is a city in southwestern Russia, the administrative center of Voronezh Oblast. It is located on both sides of the Voronezh River, away from where it flows into the Don. It is an operating center of the Southeastern Railway , as well as the center of the Don Highway...

 received an order to construct 50 ANT-36s for the Air Force. The Tupolev design bureau built an exact copy of an ANT-25 in 1989 for Monino
Central Air Force Museum
The Central Air Force Museum in Monino at the site of Monino Airfield 40km east of Moscow, Russia, is one of the world's largest aviation museums, and the largest for Russian aircraft...

 aviation museum.

Variant

DB-1
Tupolev DB-1
-See also:...

Unsuccessful bomber. Few built. Max speed 210 kilometres per hour (130.5 mph).

Specifications (ANT-25)

See also

External Links

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