|Type||2* Gnome-Rhone 14 krsd|
|Power at m||2*800hp|
|Weights and loads|
|Wing Load (kg/m2)||160|
|Power load (kg/hp)||2.8|
Project of the 'Light Cruiser' was initiated by P.L.Grokhovskij in 1934. General layout of this clean twin-tail monoplane was developed by V.F.Rentel (leading designer). Aircraft of mixed design (mostly wood, crew cabin - metal, control skin - fabric) had retractable landing gear and (originally) had wing span 28m and accommodation of five crew members. But with chosen engines it could not challenge even contemporary fighters. Its estimated speed was only 300km/h against 400km/h typical for fighters. Armament also appeared too light for large aircraft - rifle-caliber ShKAS machineguns.
With typical for P.L.Grokhovskij energy, he replaced V.F.Rentel by young P.A.Ivensen (then 25), who was working with R.L.Bartini and already proved himself as a designer with original individual style. After brief familiarization with Rentel's design calculations, he confirmed that 300km/h is a limit. But P.A.Ivensen found the solution, promising 500km/h!
After less than three days with drawings and pencil, radical design changes were made: wingspan was decreased to 14...16m (area 1/3 of originals!) and crew size reduced to three. Aim on the 'main flight regime' resulted in sharp increase of landing speed - 125km/h (even more for latest variants) against 90km/h allowed by regulations. Concept was backed by V.P.Chkalov. Top test pilot said: - Major difficulties will be faced not at home airfield but in combat. There I'll need an advantage in speed and maneuver which will guarantee a victory. Otherwise I will not need to land after being shot down easily. But if I win, I'll land it on any speed.
Except Ivensen, other experts were invited
to work on G-38:
M.V.Orlov - Head of the SNII (Samoliotnyj NII) GVF Strength Department
A.K.Martynov - Professor of airdynamics at TsAGI
V.N.Belyayev - Professor at TsAGI, specialized in loads calculations
V.I.Korovin - designer
Pair of 20mm cannons was added to the fuselage-mounted machineguns. Second defensive gun was added. The wing was made unusually strong - it had to withstand very high load... and undisclosed in official project external bomb load and additional fuel tanks.
Wind tunnel mockup was ready in a short time. Woodworkers gave it black-polish finish, that resulted in the nickname piano. Tests results were more than optimistic - aircraft of unusual layout promised good stability and speed 550km/h with selected engines. Full-size mockup for State Approval Commetee was completed in 2.5 months. Blueprints were send to assigned factory (at Leningrad) on readiness, and arriving parts immediately went to the assembly. Finally, mockup was installed in the hangar of the Central Moscow Airfield (Khodynka).
At the end of 1936 aircraft was almost assembled, despite delays originated from sharing of construction facilities with one of (which?) A.S.Yakovlev designs. Concentration of P.L.Grokhovskij on designs and inventions resulted in weakened organizational structure in his Experimental Institute. Institute was disbanded, all projects terminated.
Soon became known that H.Fokker built at the same time (1936) aircraft with similar layout and same engines. It was flown with success. Two mass-built twin-tailers of WW-II (FW-190 and P-38) also had a lot in common with G-38...