Valmet Vihuri

Valmet Vihuri (Finnish for Gale) was a Finnish advanced two-seat fighter trainer aircraft, serving in the Finnish Air Force between 1953 and 1959. A few airframes have survived, as in the Central Finland Aviation Museum in Finland.

History

In spite of their economic problems, the aircraft manufacturer Valmet began designing a new aircraft in the beginning of the 1950s, to replace the aging FAF VL Pyrys. Martti Vainio was the chief designer of the project. Most of the planning was made by the aeronautic engineers L. Hämäläinen and T. Mäntysalo in 1948–49. The Bristol Mercury was chosen as the engine, since there were no other alternatives. The Mercury was license made in Finland for the Bristol Blenheim bomber. The prototype (VH-1) made its first flight on February 6, 1951, in Tampere, piloted by captain Esko Halme. After the successful test flights, the FAF ordered 30 aircraft of the production series, called Valmet Vihuri II on February 27, 1951. In the autumn of 1954, the air force ordered a further 20 aircraft of the developed version Valmet Vihuri III. All the aircraft of the third version were handed over to the air force on January 15, 1957.

Valmet built 51 Vihuri's in three different series (I-III) in Kuorevesi and Tampere. The aircraft had the registration codes VH-1 through VH-51.

Operational use

The Vihuri aircraft became the most-used aircraft in FAF service by the mid-1950s. The aircraft was subject to many accidents, and the press raised a lot of concerns about these. The safety of the Vihuri even became a matter for the government. In May 1959, the aircraft was permanently grounded after the death of the Finnish prime minister's son in the aircraft type. Attempts were made to sell the aircraft to Tunisia, without success.

After the inspection, it became apparent that the type and its design was sound; most of the accidents were due to pilots' often grave flight-regulations violations, and the fact all airframes were well worn by the end of the 1950s. The other problem were the engines. The engines used, Tampella Mercury, were recycled engines of wartime Bristol Blenheim bombers, which were already thoroughly worn out. The planes were sold for scrap to Moser OY. One airframe, VH-18, survives in the Central Finland Aviation Museum, and the fore fuselage of another, VH-25, is being restored. The canopies of the scrapped aircraft remain today as the roof windows of the Kuusakoski metal-recycling plant in Espoo.

Operators

 Finland

• Finnish Air Force

Specifications (Valmet Vihuri II)

Data from Jan'e All The World's Aircraft 1956–57^[1]

General characteristics

• Crew: Two
• Length: 8.80 m (28 ft 9 in)
• Wingspan: 10.4 m (34 ft 1 in)
• Height: 3.86 m (12 ft 8 in)
• Wing area: 18.86 m² (203 sq ft)
• Empty weight: 2,174 kg^{[citation needed]} (4,793 lb)
• Loaded weight: 2,678 kg (5,892 lb)
• Max. takeoff weight: 2,884 kg (6,345 lb)
• Powerplant: 1 × Bristol Mercury VIII 9-cylinder air-cooled radial, 612 kW (820 hp)

Performance

• Maximum speed: 432 km/h (233 knots, 268 mph) at 3,700 m (12,100 ft)
• Cruise speed: 327 km/h (177 knots, 203 mph) at 1,000 m (3,300 ft)
• Range: 665 km^{[citation needed]} (413 mi)
• Endurance: 2.5 hours^{[citation needed]}
• Service ceiling: 8,900 m (29,190 ft)
• Rate of climb: 11.5 m/s (2,263 ft/min)

• Guns: 2× 7.7 mm Browning machine guns
• Bombs: 4× 25 kg bombs

Notes

This aircraft is not to be confused with the Finnish fast bomber variant of De Havilland Mosquito, with DB 605 engines, a project which never materialized. In 1943 the FiAF HQ asked VL if it would be possible to build a copy of the Mosquito with DB605 engines. Two crashed British aircraft would have been requested from Germany to serve as models. The primary attraction was the wooden construction (something that the VL was familiar with). The inquiries indicated that serial production could be started sometime in 1946, as there were other aircraft on queue, and there were difficulties in getting just about everything needed to produce a new aircraft. The new aircraft was also to be named "Vihuri".

Preserved aircraft

The Central Finland Aviation museum is displaying the VH-18, which is the only preserved Vihuri. It gathered 802 flying hours, after which the aircraft served as an educational machine at the Air Force Academy in Kauhava.

References

• Bridgman, Leonard. Jane's All The World's Aircraft 1956–57, New York: The McGraw-Hill Book Company, 1956.
• Kalevi Keskinen, Kari Stenman, Klaus Niska: Suomen ilmavoimien historia 14 - Suomalaiset hävittäjät, AR-Kustannus ky, 1990. ISBN 951-95821-0-X

External links

Wikimedia Commons has media related to Valmet Vihuri.

• Pictures from the scrapping of the Vihuris