We demonstrate that the 337-nm emission from neutral nitrogen molecules, pumped via incoherent electron-impact excitation in circularly polarized femtosecond filaments, is oscillatory superfluorescence (SF) rather than amplified spontaneous emission. Time-resolved measurements reveal that both the pulse duration and the emission delay scale as $P^{-1/2}$ with nitrogen pressure, providing a definitive signature of gain-swept SF. These dynamics are quantitatively reproduced by bidirectional Maxwell-Bloch simulations that incorporate impulsive electron-impact excitation and fine-structure quantum beats. Our results demonstrate that macroscopic quantum coherence emerges following ultrafast electron-impact pumping and persists in atmospheric-pressure plasmas despite rapid collisional dephasing. These results establish femtosecond filaments as a robust platform for studying collective molecular phenomena and provide a framework for generating remote, coherent UV sources in the atmosphere.

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• Collective effects in quantum optics
• Electronic excitation & ionization
• Superradiance & subradiance
• Air lasing