As the airship moves around the sky the image is visible on the exterior of the craft to {HEAD ~ observers} on {TAIL ~ the ground} 
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As the airship moves around the sky the image is visible on the exterior of the craft to { HEAD ~ observers } on { TAIL ~ the ground }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL