Elev-8 Pitch Over And Crash
GlassKNees
Posts: 181
Took my (V2) Elev-8 out for some practice doing coordinated turns. Aircraft uses a brand new APM 2.6 (clone) flight controller/autopilot; motors are stock KA outrunners with the 30A ESC's that came with the kit. Props were 10". It flew fine for about six minutes - was flying in Stabilize mode. It was warm and moderately humid with a light breeze. All of a sudden the aircraft just pitched over and fell out of the sky - tried to increase throttle, but there was no time to recover (don't even know if the motors responded). I did notice an occasional twitch/wobble during the flight but attributed it to the breezes. I had full control land it was flying steady, almost in a hover about 15 feet up when it pitched over.
I was flying in a limestone quarry, so it hit on a hard surface. I had just replaced the #3 motor the day before (some FOD found between the magnets and rotor) - copter must have hit on the #3 motor as I was unable to move the spindle; iit's mount is broken, however, the boom doesn't appear to be bent at all. One other prop shattered at the hub. Only other obvious damage is the GPS mast is broken.
I have had a series of crashes over time where the aircraft would suddenly flip over and crash. This time it didn't flip - it just pitched over and fell. I had suspected either bad ESC's or motors. This time, I have no clue. A review of the dataflash logs provided no insights. So I thought I'd throw this question out to the community: Has anyone else experienced any sudden loss of control - pitch over and crash? I'm beginning to be suspicious of either the motors and/or ESCs.
My other Elev-8 has been outfitted with Tarot 4006 620KV motors which are the same as on my Tarot FY680 Pro - both aircraft fly fine - nice and stable. Both are also controlled with clone APM 2.6 controllers.
I was flying in a limestone quarry, so it hit on a hard surface. I had just replaced the #3 motor the day before (some FOD found between the magnets and rotor) - copter must have hit on the #3 motor as I was unable to move the spindle; iit's mount is broken, however, the boom doesn't appear to be bent at all. One other prop shattered at the hub. Only other obvious damage is the GPS mast is broken.
I have had a series of crashes over time where the aircraft would suddenly flip over and crash. This time it didn't flip - it just pitched over and fell. I had suspected either bad ESC's or motors. This time, I have no clue. A review of the dataflash logs provided no insights. So I thought I'd throw this question out to the community: Has anyone else experienced any sudden loss of control - pitch over and crash? I'm beginning to be suspicious of either the motors and/or ESCs.
My other Elev-8 has been outfitted with Tarot 4006 620KV motors which are the same as on my Tarot FY680 Pro - both aircraft fly fine - nice and stable. Both are also controlled with clone APM 2.6 controllers.
Comments
Both failures occurred on throttle up from the ground, so no damage was done. It just rolled when the ESC blew.
Parallax sent me new ones, but I am replacing all with new ones.
I hope to complete the repairs tomorrow (Monday) and a new set of propellers should arrive on Tuesday. It has been windy here, so it may be awhile before I can attempt any test flights.
I just received my Amazon props and I watched a video showing shaving down the Leading Edge of the prop. What the?
At one point bad solder joints were probably close to 90% of the emergency service calls I dealt with. Now that most soldering is done by computer controlled ovens or wave soldering machines they are a rare thing...well except on connectors and cables.
I have put the chassis plates together, so the next thing is to replace the broken GPS mast, install the GPS antenna and the F.C. Hope to have it assembled and re-calibrated today.
Here is the view from the rear (The box contains new propellers I ordered - they arrived today):
Now, I have to hook it up to Mission Planner and go through the configurations: accel, compass, radio, ESC. Assuming that's all successful, it will be ready for a test flight as soon as the weather cooperates - it's been really windy and hot here!
Here's a photo of my two Elev-8's - the one in the foreground is the aircraft that I just repaired; the other is my video platform.
BTW, I watched a video on an Elev-8 V3 build from Regina University - very impressed with the design and build changes. The experience you guys learned from the previous models shows.
I believe this is the video GlassKNees was referring to.
By the way, I did an endurance test, hovering under light breezy conditions. Elapsed time was around 9:20 before the voltage failsafe kicked in and it landed. I need to raise the failsafe threshold as it came down pretty fast. Fortunately it landed on a grass field. This was with a 3300 mAH lipo.