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VEF I-16
 The VEF I-16 was a prototype Latvian fighter aircraft designed by Kārlis Irbītis and produced by VEF in 1939 costing about 130,568 Lats.
Design work on the I-16 began in the autumn of 1938, when Irbitis ordered a Czech Sagitta I SR supercharged air-cooled V12 engine. Irbitis selected an engine of low frontal area and technical simplicity for easy field servicing. This led to consideration of inverted V air-cooled engines, and the options were quickly narrowed down to the 450 hp Renault 12Roi series from Franc, or 460 hp Walter Sagitta I-SR from Czechoslovakia. A trade imbalance with France meant that the Czechoslovak engine was effectively selected by default. He also ordered a two-bladed, fixed-pitch propeller from Propellerwerk Schwarz for the prototype, but there were plans to switch to a three-bladed metal constant speed propeller to be installed later. Flight instrumentation was ordered from Kollsman in the USA. The I-16 was of conventional monoplane layout with a low set wing with rounded wingtips. The prototype had fixed undercarriage with aerodynamic fairings, but production models were to have retractable landing gear. The cockpit seat and controls were designed as one unit - they could be assembled totally separately from the rest of the aircraft and then installed as a unit with only six bolts. While the prototype was unarmed, there were provisions for two machine guns in the fuselage, along with the ability to carry one additional gun under each wing.
Construction of the prototype began in late 1938 but, as it took a long time for the engine and other parts to arrive, it was not ready for flight until the spring of 1940.
 The first flight was made in the spring of 1940 by Konstantins Reichmanis. After about 20 minutes of trouble-free flight at about 1,000 metres the engine stopped. Reichmanis made a perfect deadstick landing. It was assumed that the engine problem was due to low pressure in the fuel feed. They worked on this problem and made 2-3 more flights before the Soviets invaded Latvia and all activity was stopped.
Immediately upon occupation of Latvia, the VEF was taken over by a small cadre of employees who were apparently members of the Communist underground. They formed a small militia which took control of security at the facility and watched over the activities of all other employees. After the occupation of Latvia in June 1940, the Soviet authorities ordered that all VEF aircraft be removed from Spilve Airport and, a few weeks later, all parts fabrication and assembly work was ordered suspended pending further instructions from Moscow.
Irbitis reports that they estimated a total of 36,456 man-hours of work had been devoted to the I-16, about a third of that being the engineering and design. The prototype cost 130,568 Lats (which was about $27,000 US), of which half was for the purchase of the engine and other imported parts.
 In February 1941 a Soviet official, General-Major Feodorov, became aware of the VEF designs (particularly the I-15b and I-16) which had been stored in an abandoned warehouse. In March 1941, the I-16's designer Kārlis Irbītis received orders to prepare one example each of the VEF I-12, VEF I-15a and I-15b, I-16, VEF I-17 (two variants) and VEF I-18 to be shipped to Moscow for evaluation. The I-16 still had engine problems and needed further testing, so was left behind and stayed in Riga. At about this time the Soviets began to purge VEF of 'unreliable' engineers and constructors, and one by one Irbitis' colleagues began to disappear to prison and Siberia. This, and the engine troubles, kept the I-16 in Riga until the Germans invaded in June 1941. There is no evidence that the I-16 ever wore Soviet markings. Following the German invasion of the Soviet Union, the I-16 managed to make several test flights from an aerodrome in Kalnciems. Under the Germans, work was allowed to continue on the VEF types but, as soon as each was completed, it was claimed by the Luftwaffe. When the engine problems in the I-16 were sorted out test pilots Mikelsons and E.Rudzitis managed to make a few flights from the Kalnciems aerodrome before it, too, was confiscated by the Germans and tested by the Luftwaffe. The VEF I-16 was used as training aircraft at an aviation school in Torun until 1942.
Engine: 1 × Walter Sagitta I-SR, 403 kW (540 hp)
Wingspan: 8.23 m (27 ft 0 in)
Wing area: 11.43 m² (123.0 ft²)
Length: 7.30 m (23 ft 11 in)
Height: 2.70 m (8 ft 10 in)
Empty weight: 1,100 kg (2,420 lb)
Loaded weight: 1,540 kg (3,388 lb)
Maximum speed: 483 km/h (261 knots, 300 mph) at 7,900 m (25,900 ft)
Range: 805 km (438 nmi, 500 miles)
Service ceiling: 8,100 m (26,600 ft)
Wing loading: 136 kg/m² (28 lb/ft²)
Power/mass: 220 W/kg (0.13 hp/lb)
Armament: 2x 7.9 mm Browning machine guns
Crew: One
 -------new AC-pi VEF I-16 VEF-I16-01.jpg 24-3
The VEF I-16 was a prototype Latvian fighter aircraft designed by Kārlis Irbītis and produced by VEF in 1939 costing about 130,568 Lats.
The I-16 was of conventional monoplane layout with a Walter Sagitta supercharged air-cooled V12 engine of Czechoslovak origin, a two-bladed propeller and a low set wing with rounded wingtips. The prototype had fixed undercarriage with aerodynamic fairings, but production models were to have retractable landing gear. The cockpit seat and controls were designed as one unit - they could be assembled totally separately from the rest of the aircraft and then installed as a unit with only six bolts. While the prototype was unarmed, there were provisions for two machine guns in the fuselage, along with the ability to carry one additional gun under each wing.
VEF-I16-02.jpg 24-3
In the spring of 1940 Latvian Air Force pilots made the first test flights of the VEF I-16 prototype.
After the occupation of Latvia in June 1940, the Soviet authorities ordered that all VEF aircraft be removed from Spilve Airport and, a few weeks later, all parts fabrication and assembly work was ordered suspended pending further instructions from Moscow.
VEF-I16-03.jpg 24-3
In March 1941, the I-16's designer Kārlis Irbītis received orders to prepare one example each of the VEF I-12, VEF I-15a and I-15b, I-16, VEF I-17 (two variants) and VEF I-18 to be shipped to Moscow for evaluation. The I-16 still had engine problems and needed further testing, so was left behind and stayed in Riga. Following the German invasion of the Soviet Union, the I-16 managed to make several test flights from an aerodrome in Kalnciems but soon the single example was captured by German forces and tested by the Luftwaffe. The VEF I-16 was used as training aircraft at an aviation school in Torun until 1942.
Gallery
Engine: 1 × Walter Sagitta I-SR, 403 kW (540 hp) Wingspan: 8.23 m (27 ft 0 in) Wing area: 11.43 m² (123.0 ft²) Length: 7.30 m (23 ft 11 in) Height: 2.70 m (8 ft 10 in) Empty weight: 1,100 kg (2,420 lb) Loaded weight: 1,540 kg (3,388 lb) Maximum speed: 483 km/h (261 knots, 300 mph) at 7,900 m (25,900 ft) Range: 805 km (438 nmi, 500 miles) Service ceiling: 8,100 m (26,600 ft) Wing loading: 136 kg/m² (28 lb/ft²) Power/mass: 220 W/kg (0.13 hp/lb) Armament: 2x 7.9 mm Browning machine guns Crew: One
VEF-I16-04.jpg 24-3
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