Searching in stories... |
Timeline |
Options
|
|
||
|
||
|
||
Show the latest entries |
||
Searching in stories... |
Timeline |
The Tupolev ANT-25 was a Soviet long-range experimental aircraft that was also tried as a bomber constructed in 1933. It was used by the Soviet Union for a number of record-breaking flights.
The ANT-25 was designed as the result of a recommendation by Kliment Voroshilov on 7 December 1931 to the Revolutionary Military Council Revvoyensovyet to construct an aircraft to conduct long range record flights.
The aircraft was designed by the brigade of the Experimental Aircraft Design Department of TsAGI lead by Pavel Sukhoi under the overall supervision of AndreÏ Tupolev. The first prototype, designated Experimental airplane RD-1 (also designated TsAGI-25, ANT-25), RD standing for Rekord Dalnosty, i.e. "Range Record") made its maiden flight on 22 June 1933, piloted by Mikhail Gromov and used a direct drive M-34 engine.
In September 1934 first crew of Gromov-Filin-Spirin began long range test flights on the second experimental airplane RD-2. Their record was 75 hours in the air for a 12,411 km on a single return trip, (Moscow-Ryazan-Tula-Dnepropetrovsk-Kharkov). Aircraft was unable to return back to Moscow because of a fuel shortage. RD-2 used a geared M-34R engine which substantially increased the range of the flight. For this flight Gromov was made a Hero of the Soviet Union. Still, there was no world recognition of the record because the flight was declared with return to the same point which was not achieved and the straight range Moscow-Kharkov was too short.
Gromov and Yumashev decided to straighten their next long-range flight. They want to fly the traditional long-range routes via Africa and Atlantic into South America. As crew was studying the maps, Sigizmund Levanevskiy suggested his candidacy to fly in a completely different direction - to the north. As polar aviators were extremely popular at that time his plan was considered the most plausible. Backup RD was given for Gromov's south route, but in the spring of 1935 he fell seriously ill and the flight was cancelled.
After that the preparations started for a straight record-range flight from Moscow to USA via the North Pole. On one of the airbases near-Moscow (at Shchelkovo) a downward sloping concrete runway was built of 4 km in length. On the early morning of August 3, 1935 Levanevskiy-Baidukov-Levchenko crew ascended their RD into the air. For the first 50 km of flight the aircraft ascended only on 500 m, then steadily increased it to 4-5 km and maintained an average speed of 165 km/h. After approx. 2,000 km the oil leakage was found and the aircraft emergency landed safely at Krechevits near Novgorod.
After this fault Levanevskiy was called to the Politburo meeting, where he blamed Tupolev, declaring that his single-engined ANT-25 is not sufficient for the proposed goal. It seemed as it was the death of the plane.
Still, his second pilot Georgy Baidukov, who was also an aviation engineer, disagreed and proposed Valery Chkalov for the second try. Chkalov was first sceptical about his candidacy, as he was a fighter pilot with a little navigation knowledge, but Baidukov told him the hard points in the pilotage of ANT-25 and proposed Aleksander Belyakov, who was the Chief of the Navigator course in their flight academy, as their third option. The authority of Chkalov was enough to convince Stalin for a second chance for this airplane.
In July 1936 the record was broken by Chkalov-Baidukov-Belyakov crew flying on the same plane from Moscow into Far East (Stalin's Route) for 56 hours 20 minutes the 9,374 km trip. They passed Franz Josef Land - Severnaya Zemlya - Tiksi - Yakutia - Petropavlovsk-Kamchatsky - Khabarovsk - Okhotsk Sea and landed on a sand beach of Udd island near the Amur River isthmus - currently Chkalov island.
On the next day Pravda newspaper was issued with a famous leading article "Glory to the Stalin's Sokols!". Meanwhile on the Udd island a wooden runway was constructed and on August 2, ANT-25 departed back to Moscow. The trip back lasted a week with a stops in Khabarovsk, Chita, Krasnoyarsk and Omsk with grand welcomes. For this flight the Chkalov's trio became Heroes of the Soviet Union. Two nearest islands were renamed after Baidukov and Belyakov.
While Chkalov's achievement became a world-famous record, Politburo still needed the straight flight instead of a broken line (Chkalov's straight was less then 9,000 km). Gromov was again ordered to fly directly to Brazil on August 14, 1936 on a second ANT-25, but as he prepared for the start on September 25 Brazil officials denied the reception of the Soviet plane and the flight was cancelled.
Both crews, Chkalov's and Gromov's, were now destined to fly northbound from Moscow to San Francisco.
After a year passed on June 18-20 1937 the same crew of Valery Chkalov, co-pilot Georgiy Baidukov and navigator A. Belyakov made a non-stop flight from Moscow to Portland, United States in a bad weather condition during most of the airway. After 60 hours of flight they passed Seattle, after two more hours passed Portland lighthouse on a Columbia River and headed deeper into USA territory but over the city of Yugin they founded a fuel shortage and turned back to the Vancouver military airbase. They landed on a Vancouver's Pearson Airfield (by the other sources - Barak Airfield). The 9,130 km trip took 63 hours and 25 minutes. The ANT-25 gained fame after this flight. In 1975 an obelisk was erected on an airfield commemorating this event.
Another long-range, and widely publicized feat, was the Moscow-San Jacinto non-stop trip of Gromov-Yumashev-Danilin crew, flown on 12-14 July, 1937 on a backup airplane just three weeks after Chkalov. This time the weather was better and this trip via the North Pole was 11,500 km long, and took 62 hours and 17 minutes to complete. After landing the aircraft had extra fuel for approximately 1,500 km of flight and even reach Panama, but this implied the crossing of the Mexican border without permission of the FAI sporting officials. While Gromov became an unofficial Soviet Pilot No. 1, Chkalov remained the beloved pilot of all the Soviet people. Joy of the unbelievable achievements were marred by the crash of Levanevskiy to fly the same route on a brand-new 4-engined DB-A, not on an ANT-25, declined by him.
In November 1938 Soviet record fell to the 2 UK bombers flew from Egypt to Australia (11,500 km). USSR had not continued the race, aviation design bureau works stalled due to repressions. Tupolev was put in jail, Gromov was also on a brink of arrest. On December 15, 1938 Chkalov mysteriously crashed while testing new fighter plane.
After Chkalov's death the Chief of the Aviation Industry Directorate Belyaikin, Director of the Aviation Plant which build Chkalov's fatal plane Usachyov and aircraft designer Tomashevich all fell under repressions due to sabotage. Nikolai Polikarpov escaped arrest.
The reasons for the aircraft's successes was due to the wing design, the wide-span wings gave the aircraft good range and fuel-efficiency, while they also could house large fuel tanks. The division of the wingspan to the chord was more than 13! Total amount of fuel was 52% of the take-off weight. This not only removed fuel tanks from fuselage but also compensated the wings tensions as fuel weight opposed the aerodynamics forces.
Among other theoretical works there were conducted the research of special forms of vibrations of the aircraft because of a longer wings and on a speed greater than some critical point - the so-called flutter effect.
To stay afloat in case of emergency water landing the ANT-25 used the air-filled bags of rubberised fabric.
As known from the archives the idea of the military variant of the RD airplane first came to the engineer Zhemchuzhin of the 7th sector of the Soviet Air Force Scientific Research Institute. It is unknown about the true purpose it - the slow speed, low altitude and poor maneuverability of the aircraft together with it's large wingspan made it a perfect aim for the fighter planes as well as anti-aircraft defence.
Only two aircraft were manufactured, and the type was followed by the Tupolev ANT-36. In 1934 aviation plant in Voronezh received an order to construct 50 ANT-36 for the Air Force. In 1989 Tupolev design bureau made an exact copy of ANT-25 for Monino aviation museum.
— — — = = — — —
— — — = = — — —
You choosed to show only the famous things! (Via the Options menu)