Thanks for the great videos. I appreciate they must have been tough to make. As engineers we learn way more from our failures than our successes. It sounds like you are already thinking of how to build back better and safer. Rock on!
I will have a AirBike update video by the 28th. On Dec 4th I finally got my shoulder surgery. Went 100% perfect. PT went great. My shoulder is about 90% back to full strength. Challenge I have now is funds. It will all be explained in the update. Rock On and Cheers!
Dag, thank you for the videos. They've been very helpful. Did you have telemetry on the airplane? If so, I'd be curious the current draw/temp was reported to be at the time of, and just before the failure. I wonder if the folks at Jeti (Hacker) would be interested examining the ESC to determine a cause? Thanks for all you do for the hobby...!
The only telemetry I had was hear what the battery voltage was. When we tested it in the ground she was pulling around 210 amps at max power. But once I had the wheels of the ground I was throttled back to about 70%. She was a floater and flew like a cub. I never needed 100% power to fly her. The motor acted up when I throttled down to about 50%, that's when it lost timing IMHO.
@dagtheaviator I'm really sorry for the crash, Dag. You've done an amazing engineering job on your planes, and I like many appreciate your sharing your techniques, results, and tribulations so we all can learn from them. My next large airplane will be better from your sharing. I hope Jeti asks to look at it to assess a root cause.
Some thoughts: First the cause: Could be multiple reasons. Motor short failure, or ESC failure in multiple failure modes. One thing does come to mind which stands out due to a personal experience. I have a relatively large twin motor design which I built for a customer. I usually use castle, but the motors were Eflite so the customer requested Eflite ESC’s. Run up was fine prior to the test flight. During the test flight I noticed a screeching noise and immediately I lowered the throttle and made emergency landing. Subsequent tests revealed that the ESC had very limited ability to handle any ripple current and the wiring from the battery to the ESC’s was longer than normal. ESC’s have low ESR capacitors to handle it but the ones on those ESC’s were very inferior and couldn’t. I switched to Castle and problem solved. I’ve also had three motor failures in flight. One the motor came loose and the prop jammed into the wing. The Castle ESC shut down when it detected the motor failure, saving the rest of the system and the wing from further damage. The plane actually flew home with one engine and prop dangling, and damage to one wing, as well as a loose flap whose linkage had been destroyed. The other two melted coils. In all case so the castle handled it and didn’t burn up or fall and was completely fine. So good on Castle! But let’s assume an ESC failure and input wires melted. Could completely isolate the two systems, control and ESC. Adding another receiver does add another point of failure but is probably the simplest solution. Could also add a fuse in the main power line. Or could use diodes and a second redundant control battery pack for control. I’m also a huge fan of multi engine aircraft. I pretty much only design twins or distributed propulsion aircraft. It’s great when you lose an engine and the plane comes home to a safe landing:). Well there’s multiple ways to solve this problem. It’s good to think about! What’s your plan?
I said in the crash video the motor kept losing timing. I am not sure why, but I would put the programmer on and the timing was wrong. The problem always happened on the ground. This only happened on the flight I lost the motor I heard it go out of timing, something that only happened on the ground. But this time I did not pull the throttle down fast enough and smoked the ESC.
Last year I stopped work on it as I had a bad shoulder. On Dec 4th I finally had my rotatory cuff surgery and it went 100% perfect. PT also went perfect. I am about back to 90% strength. I hope to start back on it soon. The fuse is done. The wings and tail needs covered.
@@dagtheaviator good to hear you're getting patched up I'd like to see you complete that project and move on to a zenith clearly you've got skill and passion for building
@@dagtheaviator tight at my house too i stopped flying full scale I dont know if things will get better rates are high gas is high food is high I dont know how folks are doing it I make " decent " money and I'm broke
Thank you for sharing, I would never have envisioned that type of failure.
Thanks for the great videos. I appreciate they must have been tough to make. As engineers we learn way more from our failures than our successes. It sounds like you are already thinking of how to build back better and safer. Rock on!
Thanks, and your spot on. Rock ON!
As youre describing this, im also pondering the use of an auto drogue chute that deploys in the event of system failure.
Hey Dag, love your work, big fan. I was wondering when will we get something on the Airbike?
I will have a AirBike update video by the 28th. On Dec 4th I finally got my shoulder surgery. Went 100% perfect. PT went great. My shoulder is about 90% back to full strength. Challenge I have now is funds. It will all be explained in the update. Rock On and Cheers!
@@dagtheaviator can't wait to see it. I started with woodwork and welding also. Too bad for your shoulder though, hope you get to full strength
Dag, thank you for the videos. They've been very helpful. Did you have telemetry on the airplane? If so, I'd be curious the current draw/temp was reported to be at the time of, and just before the failure.
I wonder if the folks at Jeti (Hacker) would be interested examining the ESC to determine a cause? Thanks for all you do for the hobby...!
The only telemetry I had was hear what the battery voltage was. When we tested it in the ground she was pulling around 210 amps at max power. But once I had the wheels of the ground I was throttled back to about 70%. She was a floater and flew like a cub. I never needed 100% power to fly her. The motor acted up when I throttled down to about 50%, that's when it lost timing IMHO.
@dagtheaviator I'm really sorry for the crash, Dag. You've done an amazing engineering job on your planes, and I like many appreciate your sharing your techniques, results, and tribulations so we all can learn from them. My next large airplane will be better from your sharing. I hope Jeti asks to look at it to assess a root cause.
@@cloudsplitter24@cloudsplitter24 Thanks. Have an awesome day! Rock ON!
Some thoughts:
First the cause:
Could be multiple reasons. Motor short failure, or ESC failure in multiple failure modes. One thing does come to mind which stands out due to a personal experience. I have a relatively large twin motor design which I built for a customer. I usually use castle, but the motors were Eflite so the customer requested Eflite ESC’s. Run up was fine prior to the test flight. During the test flight I noticed a screeching noise and immediately I lowered the throttle and made emergency landing. Subsequent tests revealed that the ESC had very limited ability to handle any ripple current and the wiring from the battery to the ESC’s was longer than normal. ESC’s have low ESR capacitors to handle it but the ones on those ESC’s were very inferior and couldn’t. I switched to Castle and problem solved.
I’ve also had three motor failures in flight. One the motor came loose and the prop jammed into the wing. The Castle ESC shut down when it detected the motor failure, saving the rest of the system and the wing from further damage. The plane actually flew home with one engine and prop dangling, and damage to one wing, as well as a loose flap whose linkage had been destroyed. The other two melted coils. In all case so the castle handled it and didn’t burn up or fall and was completely fine. So good on Castle!
But let’s assume an ESC failure and input wires melted. Could completely isolate the two systems, control and ESC. Adding another receiver does add another point of failure but is probably the simplest solution.
Could also add a fuse in the main power line. Or could use diodes and a second redundant control battery pack for control. I’m also a huge fan of multi engine aircraft. I pretty much only design twins or distributed propulsion aircraft. It’s great when you lose an engine and the plane comes home to a safe landing:).
Well there’s multiple ways to solve this problem. It’s good to think about! What’s your plan?
I said in the crash video the motor kept losing timing. I am not sure why, but I would put the programmer on and the timing was wrong. The problem always happened on the ground. This only happened on the flight I lost the motor I heard it go out of timing, something that only happened on the ground. But this time I did not pull the throttle down fast enough and smoked the ESC.
Do you plan on rebuilding it?
@@user-lr8sd2om1d Yep! It will be flying in 2025.
I hope that 3D printed engine is ok and you dont need to go and print much more to fix it up
I am guessing 6 jugs. Should not be that hard.
did you fly your airbike ?
Last year I stopped work on it as I had a bad shoulder. On Dec 4th I finally had my rotatory cuff surgery and it went 100% perfect. PT also went perfect. I am about back to 90% strength. I hope to start back on it soon. The fuse is done. The wings and tail needs covered.
@@dagtheaviator good to hear you're getting patched up I'd like to see you complete that project and move on to a zenith clearly you've got skill and passion for building
@@zackriden79 Thanks! I hope to have the AB in the air later this year. The only thing that may slow my down is money. Things are tight.
@@dagtheaviator tight at my house too i stopped flying full scale I dont know if things will get better rates are high gas is high food is high I dont know how folks are doing it I make " decent " money and I'm broke