Not only was the plane simply awful in appearance, and in this regard, only the French, who had simply disgustingly masterpiece planes, could compete with it, he still could not fight, although he had all the chances.
We are talking about the Polish medium bomber R-30 "Zubr".
It so happened that the car initially and constructively turned out to be an erroneous project. That happens. Initially, the Poles went the German route, trying to create a kind of universal aircraft that could be used as a passenger, transport and military aircraft. But what Heinkel did just fine did not quite work out for Cholkosh, the chief designer of this nightmare.
In general, in the second half of the 30s, the Poles conceived the rearmament of their air forces. This led to the emergence of rather peculiar structures, on the conscience of which the not entirely successful participation in the Second World War.
No, one cannot say that the Polish Air Force did not take part at all. They were able to inflict some damage to the Wehrmacht and the Luftwaffe, but, frankly, it cannot be called significant.
The development of the aircraft was outsourced to Państwowe Zakłady Lotnicze, PZL, an association of State aviation factories in Poland. Zbislav Cholkosh was appointed chief designer. Cholkosz was noted for the development of many aircraft models in Poland, then fled in time to the United States, where he devoted the rest of his life to work in the firm of Frank Pyasetsky, which produced helicopters.
At first, the new aircraft was planned as a civilian, but things were going so slowly that in the end the Polish Ministry of Aviation decided to buy a Douglas DC-2 from the Americans, and so that the project would not be lost, to give the developments in favor of the military.
The prototype PZL-30B passed the test cycle in the fall of 1936. As a result, 16 vehicles were ordered for the Polish Air Force. Export sales were also planned. Romania was to become the first potential customer. A special airplane show was organized for the Romanians.
The show ended in a nightmare. Affected by the insufficient strength of the structure, which led to the destruction of the wing. The plane crashed, killing three members of the Romanian delegation. Naturally, after that the purchase of the R-30 by Romania was dropped. The assembly of aircraft was also suspended for their own needs.
It must be said that the PZL were already loaded with work on the PZL P-23 "Karas" light bomber and the PZL P-37 "Los" medium bomber. These were rather promising designs for their time, in contrast to the P-30. Therefore, PZL quite successfully gave the project to LWS. Lubelska Wytwornia Samolotow, Lublin Aviation Plant.
The R-30 was originally an outdated project, with angular shapes like the French Amiot 143, Potez 540 or our TB-1. Not a masterpiece of grace and aerodynamics.
Potez 540
Amiot 143
TB-1
The aircraft was supposed to have powerful defensive weapons and carry up to 1200 kg of bomb load. Probably, it was these plans that made it possible to push the plane into service. The R-30 was supposed to combine the specializations of a bomber, a reconnaissance aircraft and a training aircraft for training crews.
Many countries worked on projects of a multipurpose universal aircraft of the "bomber-heavy fighter-reconnaissance" type. Some (Germans, Dutch) succeeded, the Poles also wanted to get such an aircraft at their disposal.
In addition, if the LWS "screwed up" the work on the R-30, then it could be replaced by the R-37 "Los", which was developed in parallel. Or vice versa.
The designer Jerzy Theisseir was appointed the immediate supervisor of the work. The designer and his team honestly tried to improve the design's capabilities, to enhance its strength characteristics, but little came of it. But the weight of the aircraft increased considerably, which made it necessary to reduce the practical bomb load.
The aircraft's combat effectiveness became highly questionable.
The main problem is the engines. Initially installed motors from "Pratt & Whitney" "Wasp Juniors" gave out no more than 400 hp. each, because the test institute ITL (the Polish analogue of our TsAGI) recommended to install something more powerful, otherwise the plane had no chance of life at all.
The only thing that could be used was the licensed British Bristol "Pegasus" VIII with a capacity of 680 hp. With these engines, the Zubr became a little more like an airplane.
However, flight performance remained below all reasonable limits. Fuel tanks with a capacity of 1240 liters provided a range of 750 km at a cruising speed of 280 km / h, but the "highlight" of the R-30 was that it was impossible to take a full supply of fuel with a full bomb load. The plane simply did not take off the ground. With full tanks and without bombs, the plane could fly up to 1250 km, with bombs and a fuel supply of 750 liters - no more than 600 km.
So the only role the Zubr was good for was a training plane. The combat capability of the P-30 became more and more conventional. Although the LWS company did everything possible to ensure that the aircraft could not become a conventional combat-ready unit.
The manual cable retraction system was replaced by an electric one, the struts were retracted by turning into the engine nacelles.
The installation of a more powerful propeller group and the subsequent strengthening of the aircraft structure caused an increase in the aircraft mass by almost a ton.
It had to be strengthened precisely because of the incident with the Romanian delegation. Then, in November 1936, the Poles demonstrated the aircraft with new engines, without bothering to reinforce the structure. As a result, the wing came off, the car fell, burying the pilot engineer Rzhevnitsky, the technician Pantazi and two Romanian officers under the rubble.
According to the official version of the Poles, the tragedy was caused by the fact that one of the Romanian guests on board for some reason opened the emergency hatch, the door of which was unfastened from the fasteners and hit the screw. The resulting vibrations shook the entire structure, the engine "left" from the motor frame and hit the wing. As a result, the wing fell apart.
In fact, it was simply necessary to strengthen the structure after installing more powerful and heavier engines.
The wing, engine mountings, mountings were significantly reinforced. The classic PZL-30BII plumage was replaced with a two-fin one with washers at the ends of the stabilizer. This increased the mass by another 780 kg. Accordingly, the bomb load was reduced to 660 kg, almost half of the original calculations.
Meanwhile, the single-engine PZL-23 "Karas" took on board about the same load, flew about as slowly, but cost less, if only because of the single-engine layout. The PZL Р-37В "Los" was also cheaper than the "Zubr", but the "Zubr" did not promise higher flight characteristics.
The crew consisted of four people. The cockpit was located in a very original way, at the top of the fuselage, but asymmetrically, to the left of the center line. This gave an acceptable view and provided a passage between the bow and rear cockpits.
The defensive armament consisted of five 7,7 mm Vickers machine guns: two in the upper electric retractable turret turret, two in the front electrified turret and one in the lower fuselage hatch.
Serial "Bison" received the designation LWS-4A. Production aircraft differed from prototypes by the return of a single-fin tail unit, and the first 15 aircraft did not carry any weapons, because they were supposed to be used as training vehicles for training and retraining pilots.
The first months of Zubrov's operation revealed a huge number of shortcomings. The main headache was caused by the landing gear, which stubbornly did not want to get into the locks during release, which caused several accidents during belly landing.
Complaints and complaints were sent to the plant in Lublin. The factory workers dealt with the problem very quickly: they simply took and locked the landing gear in the extended position. The Zubr turned into an aircraft with a non-retractable landing gear, along the way, the problem of overloading the aircraft's electrical system, which lacked power, was resolved, and some devices had to be turned off to retract the landing gear.
But after such an intervention, the electrician stopped malfunctioning.
The Zubr served as a training aircraft for the Polish Air Force until the very beginning of the war. As a training aid for novice pilots, the PZL-30 / LWS-4A served until the outbreak of World War II. The car turned out to be very comfortable to fly and easy to operate.
But the beginning of the Second World War was the end of the career of this aircraft. The Germans managed to bomb almost all of the Zubrs, and several of the surviving LWS-4A were captured.
The zealous Germans, who did not throw away anything when they were born, found use even for these handsome men. Despite the absence of at least some acceptable flight characteristics, the Zubrs came in handy. They were used as training at the bomber training center in Schleisshain up to and including 1942. Then they wrote off.
One plane lived a little longer. It was the LWS-6 prototype that made it to the museum. And until 1945 he served in the aviation museum in Berlin as an exhibit. This "Zubr" was destroyed, like its colleagues, as a result of the American air raid in 1945. Together with the museum.
In general, the LWS-4A "Zubr" can serve as another proof of the postulate of Andrey Nikolaevich Tupolev that "Only beautiful airplanes can fly well."
LTH LWS-4A
Wingspan, m: 18,50
Length, m: 15,40
Height, m: 4,00
Wing area, м2: 49,50
Weight, kg
- empty aircraft: 4 751
- normal takeoff: 6 100
- maximum take-off: 6 800
Engine: 2 x Bristol Pegasus VIIIC x 680 hp
Maximum speed km / h: 320
Cruising speed, km / h: 280
Practical range, km: 750
Maximum rate of climb, m / min: 384
Practical ceiling, m: 6 200
Crew, prs: 4
Armament:
- two 7,7 mm machine guns in the nose turret;
- one 7,7 mm machine gun in the tail;
- bomb load 440-660 kg.