Corrected entry: As Kirk realigns the warp core to restore power and save the USS Enterprise from crashing to Earth, Sulu tells Spock: "Without power, we'll incinerate on re-entry." It shows Kirk restoring power after it plummets below the clouds, which is well beyond the point where they would have been incinerated.
tedloveslisa
3rd Oct 2016
Correction: Kirk restores the power before the ship goes below the clouds. They were using the thrusters to slow their descent well before they broke the cloud barrier.