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--></style></head><body lang="EN-US" link="blue" vlink="purple"><div class="WordSection1"><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d">In a move to keep APRS relevant, there was some useful feedback on the idea to extend the speed range of APRS reporting.  I like the transition at Mach 1 (670 kts).</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d">So here is the way to handle speeds above Mach 1 and it works for both</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d"> MicE and CSE/SPD values of X speed field.</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d">If X Less than or equal to 670 then SPEED = X in Kts</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d">If X is greater than 670 then SPEED is 135X -90000  in Kts</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d">You do not even need to do the math.  You can just use some pre-calculated values shown here:</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d"> </span></p><div id="divtagdefaultwrapper"><p><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d">779 = 15,200 knots space station</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"></span></p><p><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d">682 =     2100 knots Mach 3</span></p><p><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d">678 =     1600 knots military</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"></span></p><p><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d">677 =     1340 knots Mach 2</span></p><p><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d">675 =     1200 knots Concorde</span></p><p><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d">670 =       670 knots Mach 1</span></p><p><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d">These remain in Knots because that is the APRS standard for speed, but of course you can also display them in MPH if you want to make that conversion which I think all PILOTS use.</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d">Bob, WB4APR</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1f497d"> </span></p><p> </p></div></div></body></html>