The relationship between propeller pitch and drone performance comes down to how much air each blade pushes per rotation. A lower pitch prop—say 4 inches on a 5-inch frame—moves less air per turn, which means your motors spin faster to generate the same thrust. A higher pitch prop like 5.1 or 5.5 inches moves more air per rotation, so you need fewer RPM to produce equivalent thrust.
Here's where it gets practical. Lower pitch props are more efficient at lower throttle levels because they require less power to hover and cruise. If you're flying around casually or doing technical moves that don't demand constant high speed, you'll get noticeably longer flight times. The trade-off is that top speed suffers because you've got physical limits on how fast motors can spin. You'll probably max out around 120-140 mph depending on your specific motor and battery setup.
Higher pitch props flip this around. They let you hit higher speeds because they generate more thrust per rotation, so you can keep accelerating even as your motors approach their RPM ceiling. I've seen racing quads with 5.1 or 5.5 inch props hitting 160+ mph without too much struggle. The problem is efficiency tanks. At low throttle, high pitch props are working harder than they need to, wasting battery capacity. Your flight time drops maybe 20-30 percent compared to lower pitch alternatives.
Most people flying FPV racing or freestyle end up in the middle with standard 5-inch props at 4.8 to 5.0 pitch. This gives you speed potential while keeping efficiency reasonable. I'd honestly start there unless you have a specific goal. If you're chasing top speed records or gate racing, go higher—5.2 to 5.4. If endurance and smooth flying matter more, drop to 4.6 or 4.8. Motor weight and KV rating matter too; paired with the right motor, even modest pitch changes make real differences. Test what you have and actually time your flights instead of guessing.
