Due to the sloping of the truncated cones sidewall, {TAIL ~ the gap} 70 gets bigger through the length of {HEAD ~ the air horn} 50 
Due to the sloping of the truncated cones sidewall , { TAIL ~ the gap } 70 gets bigger through the length of { HEAD ~ the air horn } 50
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH