Even a high-altitude plane such as the U-2 would be fairly difficult to misidentify as a satellite. For obvious reasons, U-2s and SR-71s and such didn't employ lights while operating at altitude; therefore the only way to see them would be via reflected light. It would need to be reasonably long after sunset, or else the sky isn't dark enough to credibly see a satellite -- but not so long after sunset that the plane would be in the earth's shadow. Satellites have a similar window of observability -- but it's much longer, because they're much higher. A high-altitude plane would have a very small window. Moreover, it would need to execute that turn without crossing the terminator: as soon as any reflecting object crosses the terminator, that reveals its altitude.