Hey Everyone,

Recently I was told by a pilot that has more experience than myself and had an unfortunate event that it's better to have failsafe disarm than it is to have it go to low throttle. He first quoted a story about how he had a fly-away when a quad went into failsafe and then mentioned how continuing to have throttle after losing signal could result in injuries, especially if the quad is in acro mode which made sense. 

Anybody have any opinions one way or the other on this topic? I am thinking it'd make a good example video for the safety vid so that I can get people to volunteer when they realize I am talking low-pressure filming.

I've heard both pros and cons on this. For me, I am usually flying less then ten feet off the ground and if I have problem, it goes into auto level and the throttle is set to drop the craft at a couple of meters a second. That said I am not flying anywhere near people and I am usually under a tree canopy. What is right for me may and probably isn't right for everyone. To me it has to do with the type of flying you're doing and where you're flying.

I always set my FS to fully kill the throttle. If I have a problem, I want to have it just fall out of the sky than come down as a spinning piece of mass destruction that I have no control over.

For me it's zero throttle just seems to be more sensible and safer

Absolutely. I set failsafe to hold channel values for one second and then cut the throttle.

I'd hate to have a child go up to my quad after it fell from the sky and be injured by it trying to spin the props.

The way it should be set is in the word itself "fail safe".

I must add though that on my larger GPS birds, I have them set that on loss of signal they return to home location at the height of 75 feet then autoland. BUT I also have a killswitch programmed that shuts down throttle in case of emergency

(03-Apr-2017, 03:02 PM)RENOV8R Wrote: I must add though that on my larger GPS birds, I have them set that on loss of signal they return to home location at the height of 75 feet then autoland.  BUT I also have a killswitch programmed that shuts down throttle in case of emergency

Yeah, failsafe has to be a bit different when you're talking about several kilos of craft and equipment that's probably worth significantly more than any FPV racing quad.

They are also smart enough to understand when they are on the ground and to disarm once they are.

Talking about failsafe, you also have to be aware what your rx does (i.e. test, and configure if needed/possible).

Most of my spektrum stuff centers channels / goes low on throttle for a second or two before the FC recognizes failsafe and shuts off. Some of my full size recievers save the channel values sent during bind process as failsafe presets, but not the sats i think, so most of my newer quads won't disarm until the FC failsafe kicks in.

However, it seems to work reliably... Also be aware, to get control back after FC failsafe, you need to disarm and re-arm.



PS: Racetrack racers should disarm as fast as possible though - rx set to "no pulses" if possible, and FC to drop immediately.

I'm really annoyed by failsafe at the moment. I just built an Armattan Armadillo at the weekend as a 3S machine and it's flying really nicely - until it gets about 15 metres away and then it drops out of the sky.

The only place I could fit my LemonRX satellite was behind the FPV camera. I've just tried wrapping the satellite in foil, just in case interference from the camera was causing it to have poor reception, but that didn't help at all.

I'll try moving the satellite outside the body and see if that makes any difference.

(03-Apr-2017, 04:37 PM)unseen Wrote: I'll try moving the satellite outside the body and see if that makes any difference.

I had one failsafe case on my rage210 when i was relatively close, but it was most likely just bad antenna placement - i had both antennas on top in a V-shape, and then while flying straight away from myself in fast forward angle, the x-arms exactly covered both antennas... I could imagine a similar case if your quad was relatively high from your point of view?

PS: In my video above i think that actually the sat browned out and rebooted due to voltage sag...

(03-Apr-2017, 01:40 PM)unseen Wrote: Absolutely. I set failsafe to hold channel values for one second and then cut the throttle.

I'd hate to have a child go up to my quad after it fell from the sky and be injured by it trying to spin the props.

The way it should be set is in the word itself "fail safe".

I have actually seen youtube videos of this exact thing. One in particular i remember is a dji that went down (props still spinning and gopro still filming). The little boy kept trying to throw it back in the air! Several times! Finally his mother came outside and got him away from it only to have his older sister laugh and take off running towards it to do the same damn thing! 
Couldnt find the video Im remebering but its on youtube

And coming from brushed motors and toy quads that just hold last command (dumb imho). If brushed motors are not killed quickly they burn up fast when stuck in a tree. Let alone a brushless motor and esc getting bound up and left untill its recovered. Even on a large camera rig if the motors never shut down and you get stuck in the top of a tree, bad things could happen Id rather it fall and break than burn to ash or start a fire somewhere. Just my 2 cents

    Don't think you'd want to try and pick this up and throw it hahaha

(03-Apr-2017, 04:47 PM)fftunes Wrote: I had one failsafe case on my rage210 when i was relatively close, but it was most likely just bad antenna placement - i had both antennas on top in a V-shape, and then while flying straight away from myself in fast forward angle, the x-arms exactly covered both antennas... I could imagine a similar case if your quad was relatively high from your point of view?

PS: In my video above i think that actually the sat browned out and rebooted due to voltage sag...

I do try to make sure that antennas are visible from the ground and I have the antennas placed exactly how you say. At certain angles, they may well both be in the frame's shadow though.



On the other hand, I also have other quads with the same receiver and similar antenna placement and I can get 500m on those without any trouble at all. This is the second quad I've had this trouble with. The other one is a really cramped 130mm build and in both cases, the LemonRX satellite is really close to either an FPV camera or a VTX.

I'll try repositioning the receiver and see what happens. I'd certainly like to understand the problem properly so I can avoid doing it again!

(03-Apr-2017, 05:47 PM)RENOV8R Wrote: Don't think you'd want to try and pick this up and throw it hahaha

Lol if a kid watched that one crash land they'd probly think the aliens just landed

So general consensus is to kill the motors... good! This is what I was assuming was the right thing to do out of common sense but I figured before I made an example video about it I should ask.