BŻ-4 Żuk

infobox Aircraft
name = BŻ-4 Żuk
type = Helicopter
manufacturer = Główny Instytut Lotnictwa



caption =
designer = Bronisław Żurakowski
first flight = 10 February 1959
introduced =
retired =
status = Cancelled
primary user =
more users =
produced =
number built = 1 prototype
unit cost =
developed from =
variants with their own articles = The BŻ-4 Żuk ("Beetle" in Polish) was a Polish four-seat light helicopter built in the 1950s. Although it pioneered a novel rotor and transmission system, it never entered series production.

Design and development

Work on the BŻ-4 Żuk began at the research institute "Główny Instytut Lotnictwa" - Main Aviation Institute in Warsaw in 1953, under the leadership of Dipl. Ing. Bronisław Żurakowski, who had earlier designed the experimental BŻ-1 GIL helicopter, the first successful rotating-wing aircraft built in Poland. Due to the delicate political situation in postwar Poland (Soviet influences and centrally planned economy), progress was slow. The main object was to produce a simple and inexpensive general use light helicopter. Its purpose was also to develop and test the novel rotor and transmission system, which eliminates vibration and improves control. Initially it was designated GIL-4.Cynk 1959, p. 72.]

The BŻ-4 Żuk was based on a single main three-blade rotor powered by an indigenous one 320 hp Narkiewicz WN-4 piston engine located in a fuselage made of a steel frame, behind a cabin section. It had an open frame rear boom structure and a fixed four-wheel undercarriage. Main rotor was untypical, for it had a smaller upper steering rotor and was fitted with an automatic stabilization system, of the Hiller principle. The cabin had four doors with two front seats and a rear bench. There were two fuel tanks, 220 l in total.

Four main variants were planned: a passenger version accommodating a pilot and three passengers, an ambulance variant carrying pilot, one stretchers and an attendant, an agricultural variant carrying pilot and spraying or dusting equipment and a dual control trainer.

Testing and evaluation

The first prototype of the BŻ-4 Żuk four-seat helicopter was manufactured and displayed publicly in the Polish Aviation Day Exhibition in August 1956. Due to a long program of ground testing and fixing faults, it flew first only on 10 February 1959 and completed 17 flights for a total of 3 hrs, 40 minutes. The Żuk was still in the development stage when further work was cancelled in favor of the licence production of the Mil Mi-1, that had already started in WSK PZL-Świdnik. The prototype was damaged during landing on 31 August 1959, and despite being repaired, it was not used again. Two additional prototypes were not completed.

One damaged and incomplete prototype is preserved in the Polish Aviation Museum in Kraków.

pecifications (BŻ-4)

aircraft specifications

plane or copter?=copter
jet or prop?=prop
ref=Babiejczuk and Grzegorzewski
crew= one, pilot
capacity= three passengers
length main= 10.55 m
length alt= ft in ) (fuselage
span main= 12 m
span alt=39 ft 4.5 in
height main= 2.8 m
height alt=
area main=
area alt=
empty weight main= 1,050 kg
empty weight alt= 2,313 lb
useful load main=450 kg
useful load alt=
loaded weight main=1,500 kg
loaded weight alt= 3,307 lb
max takeoff weight main=
max takeoff weight alt=

engine (prop)= Narkiewicz WN-4
type of prop= 7-cylinder air cooled radial engine
number of props= 1
power main= 320 shp
power alt= 237 kW

max speed main= 156 km/h
max speed alt= 97 mph
cruising speed main= 125 km/h
cruising speed alt= 78 mph
range main= 260 km
range alt= 161 miles
ceiling main= 3000 m
ceiling alt=
climb rate main= 4.6 m/s, 276 m/min
climb rate alt=

loading main=
loading alt=
power/mass main=
power/mass alt=

armament=

ee also

aircontent
related=
*BŻ-1 GIL
similar aircraft=
*Sud-Est SE-3120 Alouette - Sikorsky S-52 - PZL SM-2 - Bristol Sycamore

lists=

see also=

References

Notes

Bibliography

* Babiejczuk, Janusz and Grzegorzewski, Jerzy. "Polski Przemysł Lotniczy 1945-1973" (in Polish). Warsaw: Wydawnictwo MON, 1974. No ISBN.
* Cynk, J.B. "Pictorial Museum of Polish Aviation." "Air Progress", Fall 1959.
* Krzyżan, Marian. "Samoloty w Muzeach Polskich" (in Polish). Warsaw: Wydawnictwa Komunikacji i Łącznośc, 1983. ISBN 832060-432-X.
* Green, William and Pollinger, Gerald. "The Observer's Book of Aircraft, 1958 edition". London: Fredrick Warne & Co. Ltd., 1958.
* Lambermont, Paul. "Helicopters and Autogyros of the World". London: Cassell, 1958.

External links

* [http://avia.russian.ee/helicopters_eng/pzl_zuk.php BŻ-4 Żuk]
* [http://test.knl.meil.pw.edu.pl/galerie.php?id=43 Photo gallery]