config: reduce aircraft count to 6

config.js

@@ -421,7 +421,7 @@ window.CONFIG = {
         enabled: true,            // false removes aircraft and contrails
         altitudeKm: 14,           // cruise altitude
         climbKm: 100,             // climb/descent run to and from cruise
-        count: 25,                // simultaneous aircraft (max 240)
+        count: 6,                 // simultaneous aircraft (max 240)
         speedKmh: 850,            // mean ground speed
         speedVar: 0.18,           // +/- speed deviation (0..0.5)
         minLegKm: 60,             // shortest leg (no taxi hops)