so i finally binned my 5inch pretty hard into a concrete barrier at the track last weekend, was going maybe 80kph and just slightly misjudged the gate exit. front right arm snapped clean off and took the motor with it, stator looks bent which i kind of expected. the other three motors seem fine spinning by hand, no grinding or anything weird.

my question is whether its worth trying to source just the arm from the frame manufacturer ? its an iFlight Nazgul frame so parts should exist ? or if the damage to the carbon near the stack mount means i should just grab a whole new frame. theres a hairline crack running from where the arm snapped toward one of the standoff holes and im not sure how sketchy that is structurally. i dont want to rebuild and then have it fold on me at speed again.

also the motor, its a 2306 2450kv and i only have one spare. thinking of just replacing all four while im in there since the others have probably got some hours on them anyway. or is that overkill if they spin fine?

hairline crack toward a standoff hole is a no for me personally, especially on a 5inch you're pushing hard. carbon can look fine and then just delaminate suddenly under load and you really don't want to find out at speed. iFlight usually sells replacement arms pretty cheap but if the crack is on the main plate thats a different story ? worth looking closely at whether its the arm itself or the body of the frame.

on the motors, honestly if you've got real hours on the other three and you're already in there rebuilding, just replace them all. the cost difference is like $30-40 and you're not going to be wondering if one of the old ones decides to die mid-flight two weeks from now. i always do a full motor swap when a frame takes a serious hit, too much vibration damage can be hidden in the bearings that you wont notice until its too late.

did the esc survive? thats the thing i always forget to check after a hard crash on that side of the quad, sometimes the motor looks like the only casualty but the esc phase wires are shorted or the mosfets took a hit. had a 2306 situation a while back where i swapped the motor and it still just twitched on that corner ? turned out the esc channel was toast.