Bob .. I’m not sure what they’re saying either. Other than the extra lifting gas required to raise the platform that much higher .. The only “booster” technology that ( imo ) they would need to operate in the stratosphere is a turbo charger or a compressor of such to draw in that ultra thin air @ 65 000’ to feed into the engine .. and then use / gear off / draw-off & in the extra air that said device would produce to fill the on-board ballast system .. adding the required weight needed for the platform to descend rather than bleeding off the costly lifting gas
“In my thought I have seen ring’s of smoke through the trees,
And the voices of those who stand looking.
Ooh, it makes me wonder,
Ooh, it really makes me wonder.”
“Stairway To Heaven”...Led Zeppelin IV