Sukhoi Su-6

infobox Aircraft
name = Su-6
type = Ground attack
manufacturer = Sukhoi



caption = Su-6 second prototype, single-seater with M-71 engine
designer = Pavel Sukhoi
first flight = 1 March 1941
introduced =
retired = 1944
produced =
number built = 3
status = Prototype only
unit cost =
primary user = Soviet Air Force
more users =
developed from =
variants with their own articles = Su-7"the Su-7 was a mixed-power fighter based on the Su-6. For the supersonic fighter-bomber see Sukhoi Su-7."

The Sukhoi Su-6 was a Soviet ground attack aircraft developed during World War II. The mixed-power (rocket and piston engines) high-altitude interceptor Su-7 was based on the single-seat Su-6 prototype.

Design and development

Development of the Su-6 began in 1939, when the Sukhoi design bureau began work on a single-seat armoured ground-attack aircraft. An order for two prototypes was placed on 4 March 1940, and on 1 March 1941 fight testing of the first prototype was begun by test pilot A.I. Kokin.cite web|url=http://www.sukhoi.org/eng/planes/museum/su6/|title=Sukhoi Su-6|work=Sukhoi Company Museum|accessdate=2007-01-07]

The flight tests indicated that the Su-6 was superior to the Ilyushin Il-2 in nearly all performance categories, however its engine exceeded its age limit before testing could be completed, and no further Shvetsov M-71 engines were available.

The second prototype flew only in January 1942 because the OKB had to be evacuated after the start of the Great Patriotic War.cite book|author=Shavrov V.B.|year=1994|title=Istoriia konstruktskii samoletov v SSSR, 1938-1950 gg. (3 izd.)|publisher=Mashinostroenie|id=ISBN 5217004770] It was armed with two 23 mm cannon, four machine guns and ten rails for aerial rockets. Test results were very favorable, and the AFRA Scientific Research Institute recommended the acquisition of a small production batch for testing under front-line conditions. A draft resolution for the production of 25 aircraft was prepared, however unfortunately for Sukhoi, it was never officially issued.

Meanwhile, combat experience with single-seat Il-2s demonstrated the need for a rear gunner. The third prototype was therefore designed with the second crewman at the expense of bomb load (decreased from 400 kg {880 lb} to 200 kg {440 lb}), and was fitted with a more powerful M-71F engine. Official tests revealed that the two-seat Su-6 had a 100 km/h (54 knots, 62 mph) greater top speed than the Il-2, although with a considerably smaller payload. When the troublesome M-71 was canceled, Sukhoi was directed to utilize the liquid-cooled Mikulin AM-42 engine. When flight tests began on 22 February 1944, the re-engined Su-6 proved inferior to the Ilyushin Il-10 using the same engine thanks to the additional 250 kg (550 lb) of armor required to protect the liquid-cooled engine and the lower power output of the AM-42 compared with M-71F.

Although Su-6 never entered production, in 1943 Pavel Sukhoi was awarded the Stalin Prize of the 1st Degree for the development of the aircraft.

u-7

As an experiment, the basic single-seat Su-6 design was converted into a mixed-power high-altitude interceptor named Su-7 (the name was later reused for a supersonic fighter-bomber). The armor was removed and the fuselage was of all-metal construction. Power came from a Shvetsov ASh-82FN piston engine with two TK-3 turbochargers in the nose and a Glushko RD-1-Kh3 rocket engine in the tail. The piston engine produced 1,380 kW (1,850 hp), while the rocket engine utilized kerosene and nitric acid for fuel and generated 2.9 kN (600 lbf) of thrust for up to 4 minutes.Shavrov 1994] Armament consisted of three 20 mm ShVAK cannon with 370 rounds of ammunition. The sole Su-7 was completed in 1944. Test flights demonstrated a top speed of 510 km/h (275 knots, 315 mph) at 12 000 m (39,370 ft) without the rocket motor, and 705 km/h (380 knots, 440 mph) with the rocket. In 1945, the rocket motor exploded during flight testing, killing the pilot and destroying the aircraft.cite book|last=Green|first=W|coauthors=Swanborough, G|year=2001|title=The great book of fighters|edition=|publisher=MBI Publishing|location=|id=ISBN 0760311943]

Operators

;USSR
*Soviet Air Force

pecifications (Su-6 prototype 3 with M-71)

aircraft specification

plane or copter?=plane
jet or prop?=prop
ref=
crew=Two (pilot and gunner)
length main=9.24 m
length alt=30 ft 4 in
span main=13.50 m
span alt=44 ft 3 in
height main=3.89 m
height alt=12 ft 9 in
area main=26 m²
area alt=280 ft²
empty weight main=4 000 kg
empty weight alt=8,820 lb
loaded weight main=5 534 kg
loaded weight alt=12,200 lb
max takeoff weight main=
max takeoff weight alt=
engine (prop)=Shvetsov M-71F
type of prop=radial engine
number of props=1
power main=2,200 hp
power alt=1,620 kW
max speed main=514 km/h
max speed alt=280 knots, 320 mph
max speed more=at 3,800 m (12,465 ft)
range main=973 km
range alt=525 nm, 605 mi
ceiling main=8,100 m
ceiling alt=26,575 ft
climb rate main=10.6 minutes to 5,000 m
climb rate alt=16,405 ft
loading main=
loading alt=
power/mass main=
power/mass alt=
more performance=
*Takeoff roll: 410 m (1,345 ft)
*Landing roll: 730 m (2,395 ft)
armament=
*2x 23 mm Nudelman N-37 cannons in wings, 90 rounds
*2x 7.62 mm ShKAS machine guns in the wings, 1,400 rounds
*1x 12.7 mm Berezin UBT machine gun in rear turret, 196 rounds
*Up to 200 kg (440 lb) of bombs

References

ee also

aircontent
related=
similar aircraft=
*Il-2
*Il-10
see also=