I have tried 15x4W & 16x4W APC for my FS90 powered

Flip 3D. Both gave tremendous vertical pull but the 15x4W spool up faster. Mind u it is hot n' humid here so engine performance will degrade. Fuel is 15% coolpower. AUW of Flip 3D is 5.5lbs. Sorry no tach reading

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Hisham