Chkalov died on 15 December 1938 while piloting a prototype of the Polikarpov I-180 fighter, which crashed during its maiden test flight.
The series of events leading up to the crash is not entirely clear.
Neither of the aircraft's two chief designers, Nikolai Polikarpov and Dmitry Tomashevich, approved the flight, and no one had signed a form releasing the prototype from the factory.
In any case, Chkalov took off and made a low altitude circuit around the airfield.
For the second circuit, Chkalov flew farther away, climbing to over 2,000 m (6,560 ft) even though the flight plan specifically forbade exceeding 600 m (1,970 ft).
Chkalov apparently miscalculated his landing approach and came in short of the airfield, but when he attempted to correct his approach the engine cut out.
Chkalov was able to avoid several buildings, but struck an overhead powerline.
He was thrown from the cockpit, sustaining severe injuries, and died two hours later.
His ashes are interred in the Kremlin Wall.

The official government investigation concluded that the engine cut out because it became too cold in the absence of the cowl flaps.
Others hypothesised that Chkalov had advanced the throttle too fast and thus flooded the engine.
As a result of the crash, Tomashevich and several other officials, who urged the first flight, were immediately arrested.
Years later, fellow test pilot Mikhail Gromov blamed the designers for flawed engine cooling and Chkalov himself for deviating from the flight plan.
Chkalov's son claimed that a plan to assassinate his father had been in the works in the months preceding his death, but the circumstances of the crash make foul play unlikely.
Despite the opinion of some, after Chkalov's death Polikarpov's reputation with Stalin was left intact, and Polikarpov continued to design aircraft.
Chkalov died on 15 December 1938 while piloting a prototype of the Polikarpov I-180 fighter, which crashed during its maiden test flight. The series of events leading up to the crash is not entirely clear. Neither of the aircraft's two chief designers, Nikolai Polikarpov and Dmitry Tomashevich, approved the flight, and no one had signed a form releasing the prototype from the factory. In any case, Chkalov took off and made a low altitude circuit around the airfield. For the second circuit, Chkalov flew farther away, climbing to over 2,000 m (6,560 ft) even though the flight plan specifically forbade exceeding 600 m (1,970 ft). Chkalov apparently miscalculated his landing approach and came in short of the airfield, but when he attempted to correct his approach the engine cut out. Chkalov was able to avoid several buildings, but struck an overhead powerline. He was thrown from the cockpit, sustaining severe injuries, and died two hours later. His ashes are interred in the Kremlin Wall.
The official government investigation concluded that the engine cut out because it became too cold in the absence of the cowl flaps. Others hypothesised that Chkalov had advanced the throttle too fast and thus flooded the engine. As a result of the crash, Tomashevich and several other officials, who urged the first flight, were immediately arrested. Years later, fellow test pilot Mikhail Gromov blamed the designers for flawed engine cooling and Chkalov himself for deviating from the flight plan. Chkalov's son claimed that a plan to assassinate his father had been in the works in the months preceding his death, but the circumstances of the crash make foul play unlikely. Despite the opinion of some, after Chkalov's death Polikarpov's reputation with Stalin was left intact, and Polikarpov continued to design aircraft.
Valery Chkalov