Awaiting clearance to start
P&W Mark-12B shadow-repulsion engines. These engines work on the audio-dynamic theory that the more noise you make, the more separation you can achieve from your shadow.
Destination: Infinity and beyond.
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Originally posted by glinda what if there is no sun that day ? is there a back-up ?
Most certainly. The Mark-12 B version can also be powered by exposure to high contrast, 24 MB or better images with > 56.3% coverage of 167 bit or better chromo-castic shadows . . . or, 2.7 grams of black crayon on glossy white paper provides 5.72 hrs reserve at nominal cruise speed.
Night flight requires an additional 15% reserve of either crayon or black shoe polish. A future Mark-12 C engine will operate with video-enhanced moon shadows as well.
Leads to a revolution in in-flight refueling methods. Look for a stock offering soon.