Results 1 to 4 of 4

Thread: Reliability - 4 or 6 or 8 motors

  1. #1
    Navigator Gerard's Avatar
    Join Date
    Dec 2013

    Reliability - 4 or 6 or 8 motors

    I am just starting with this hobby and I have been told a lot of times now that 6 motors is better then 4 motors on a multi-rotor if you don't want it failing out of the sky due to a motor failure.

    But is this true?

    If you add more motors, you add more points of failure. You have to look at the whole chain here from Flight controller through ESC to motor to prop.

    So the end questions are:
    1) can you still reliably control your craft when 1 motor (Think of the whole chain) fails?
    2) Does a 1 motor fail happen or is it usually the whole craft or multiple motors at the same time?
    3) Is a 1 motor failure actually a common cause for your craft to crash?

    I do see more expensive equipment usually hanging from Hex or Octo copters then from quads but I think this has to do more with lifting power and stability then with reliability.

    Is there anyone here that can clarify this a bit more either from knowledge or experience?


  2. #2
    Join Date
    Sep 2013
    You can definitely still control a hexacopter with a motor/prop disabled. My DJI F550, back when I had some crap props on it, threw a blade twice in flight. Both times it was sort of controllable and I was able to fly it to a controlled crash each time. An octo is probably even better.

    As for what failure modes to expect, use good power systems and good props - that will reduce the chances of failure associated with those components. Props are probably the main points of failure; props are the "gotcha" on multis which you'll find out about soon enough .

    So I prefer at least 6 motors and that's what I use 99% of the time now for my FPV flying....


  3. #3
    Fretsaw Jedi Roboforcer X2000's Avatar
    Join Date
    Nov 2013
    I'd say the more the safer... With 6 instead of 4 motors there's 33% more chance of one of them to fail, but with 4 there's 0 chance to land in the event of (one of them) failure. Where with 6 you can still land somehow if you won't touch yaw stick. And with octo without a prop you can definitely not just land it somehow, but easily to fly it back- depending on a FC is being used you might not even notice losing a prop
    If you're a noob, copy 1:1 what somebody already flies without too much questions, you'll find the answers later.
    PatrikE: I don't see anything wrong in your dump...
    you are flying it LOS... You are doing it wrong.

  4. #4
    Join Date
    Mar 2013
    While I can't disagree with anything said, I would mention that if you are just starting out, you should probably start small, simple, and cheap. You will crash learning to fly a quad, or else you will be too nervous to fly, worrying about a crash. The smaller you go, the less damage you will do to the quad, and whatever you hit. Start with a simple 250mm x or H quad, learn to fly it. then put on a simple board camera, sony 600 line with a cheap Boscam 200mw TX and a monitor and go crash that for a while. Then, if you want to move up to a nice camera rig on a brushless gimble, then 6 or even 8 motors makes sense. Stick time is more important than nearly anything else, so don't buy more than you need to get in the air at first. By the time you learn enough to need more, it will probably be cheaper and better anyway.

Similar Threads

  1. 900 KV motors vs stock DJI motors
    By jotto in forum Team-Black Sheep
    Replies: 8
    Last Post: 28th November 2013, 02:20 PM
  2. TBS Bulletproof ESC reliability
    By Sp1k3 in forum RC TECH
    Replies: 7
    Last Post: 20th November 2013, 09:44 AM
  3. TBS Bulletproof ESC reliability
    By Sp1k3 in forum Team-Black Sheep
    Replies: 4
    Last Post: 13th November 2013, 08:02 PM
  4. Replies: 22
    Last Post: 27th September 2013, 07:41 PM
  5. Replies: 5
    Last Post: 15th October 2011, 11:13 AM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts