The zero-g plane allows for a lot of experiments to be conducted without the expense of getting equipment into orbit. Apparently 80% of microgravity research can be performed in a zero-gravity plane, which is much cheaper than going to space. The flame from the lighter seemed much lazier in zero-g because without weight there is no buoyant force and therefore no convection. This makes the process of combustion more challenging because it’s difficult for oxygen to reach the fuel.
Thanks to Novespace: http://ve42.co/novespace
Special thanks to Patreon Supporters:
Tony Fadell, Donal Botkin, Nick Luchsinger, Jeff Straathof, Zach Mueller, Ron Neal, Nathan Hansen