Bartman
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the PJA props are meant for glow engines and have a more full blade profile which makes more lift. They're also slightly heavier. THe PJN props are meant for electric motors but they have less blade area so they make a little less lift. They both fly well so it just depends on what you need.
I either use all PJA or all PJN props, I don't mix them. CW (viewed from above looking down) on the top motors, CCW on the bottoms.
I either use all PJA or all PJN props, I don't mix them. CW (viewed from above looking down) on the top motors, CCW on the bottoms.