To recreate the weightless experience without going into space, the plane executed parabolic flight maneuvers, climbing sharply and descending several times during the one-hour flight.

为了不上太空而体验失重，飞机进行了“过山车”式的俯冲，在一小时的飞行期间，迅速爬升和下降。

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Glenn's flight plan called for him to spend most of the first orbit getting used to the feeling of being weightless.

VOA: special.2009.06.17

The returning Alphanauts can expect about 45 days of physical therapy to regain muscle and bone strength lost during their weightless flight, the second longest in NASA history.

CNN: Discovery brings home Alpha crew