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In November 2016 and February 2017, the C+ Square Degree Survey was carried out by upGREAT onboard SOFIA (PI: A. Tielens). We obtained the largest-ever velocity-resolved map in the [CII] line towards the Orion A molecular cloud, comprising the Orion Nebula, M43, and NGC 1977. In this talk, I will present the first science results from these observations. Not only do we identify the large-scale expansion of the Orion Nebula, due to feedback from the massive Trapezium stars in its center, but we detect the expanding bubbles around the HII regions of M43 and NGC 1977, as well. It turns out that the [CII] line, with high spectral resolution, is an ideal tracer of neutral shells that are swept up by wind-heated plasma or over-pressurized ionized gas in the bubble interiors.