To experience "weightlessness" without actually traveling into space, and orbiting the earth, a parabolic flight is used. See the flight path of Mercury, as shown in this link: https://en.wikipedia.org/wiki/Project_Mercury#/media/File:Mr3-flight-timeline-simple-2.png
While I can understand feeling weightless in the downward path (from 5.14 to 7.48 min.) - where the force of gravity is acting on both the objects (the capsule and the astronauts) equally and simultaneously, I am unable to comprehend the weightlessness when the spacecraft is ascending (during 2.37 to 5.14) because that is the period when the capsule is being pushed upwards "against gravity" by the propulsion. I therefore feel that the astronauts would be experiencing acceleration against gravity, and hence not feel being weightless. However the flight path indicates this period i.e. some portion of the ascent also to be "weightless". I am confused because of this. Please help me overcome my confusion.