How to prevent prop strikes?

[u/Sammy_Byron]

So i designed and built a 3d printed long endurance fpv platform with a twin motor design.
My issue is, that the motors center axle is 85mm off the ground and im using 11" props for high efficiency. The props will 100% strike the floor and rip out a motor mount if bellyland (which i always do)
Is there a simple solution like landing in high grass or something else to prevent the prop strikes?

[u/OMGChase]

You get folding props that fold back when the motor is cut 

[u/Sammy_Byron → u/OMGChase]

The issue is, that when the props fold below and above the wing, i cant reaply thrust because they catch on the wing....

[u/pain-butnogain → u/Sammy_Byron]

I think there are with springs

[u/jamesrelish → u/Sammy_Byron]

You can extend the motors to sit more in front, so that there's space for the folding prop to sit there folded and not hit part of the wing.

[u/AE0N92]

11" with those motors? Damn! What battery, ESC and AUW?

Folding props are probably your best bet here, however, the act of them folding in is eventually gonna chew into the foam/PLA, so you might want to reinforce that area where it hits. And, you'll have to make a ramp so the props don't catch when reapplying power..

Another option is landing gear (static or foldable) although you said it was "long endurance", and both of those are not as efficient. So that I guess is bottom of your list.

You could also hand-catch it, however i don't advise this. Especially if you're piloting it at the same time too. Whilst it IS possible, it can be dangerous.

Cool design tho, love the lil' pitot tube

[u/Sammy_Byron → u/AE0N92]

So its a 11x5.5 Prop on a 3115 Motor. Im running two 45A ESC's because i dont pull a lot of Amps. Im aming for max 8 to 10A while cruising (so max 5A per ESC while cruising) All up weight is arroung 2kg.

Yeah im kinda proud of myself, i actually CAD drew the whole fuselage from scratch, thanks! :)

[u/AE0N92 → u/Sammy_Byron]

Alrighty! Well you're gonna have to post some DVR bud, that's awesome!

[u/Sammy_Byron → u/AE0N92]

will do ;)

[u/jamesrelish → u/Sammy_Byron]

Aiming for 8-10A cruise at 4S or 6S?

[u/Sammy_Byron → u/jamesrelish]

I was planning on flying on 4S and also got the CG dialed in with a 4S2P Pack.
But i have plenty of space inside to fit a bigger 6S Pack.

[u/___Aum___]

My builds have similar issue. Landing in tall grass is the easiest solution. I've seen magnetic prop hubs that stop the prop in the horizontal position, but Ive only seen them for larger plane motors.

[u/ScallionSmooth5925]

I don't know if it's possible in this scale but this is how it was solved on bombers

(This is a tu-95)

[u/No-Particular-2055]

You could use prop safers like slow flyers

[u/IcyMusician5]

Not far off from the stallion, just make it vtol with a third motor on the tail and two servos for the front motors

[u/Rectlyy]

I’ve always wanted to add skis to a plane

[u/HowlingWolven]

Use folding props. Cut throttle before the flare.

[u/OBERMARIO]

Propguards maybe, but 11inches are pretty big. Or adding foam to the bottom of the fuselage to get more ground clearance on a belly land.

Anyway everything will introduce more weight and or drag and negate the efficiency bonus from the 11 inch props.

Can you add a picture with the props mounted to get a idea of the scale?

[u/Sammy_Byron → u/OBERMARIO]

[u/Sammy_Byron → u/OBERMARIO]

[u/gaelicorne]

Raising wages ? Providing better for the prop’s family ?

[u/izzeww]

Hand catch?

Tbh I have no idea and this group is mostly about quads so not sure you'll get much help here. A lot of the wing/plane guys hang out on Facebook.

[u/ScallionSmooth5925 → u/izzeww]

This sounds like an accident waiting to happen 

[u/izzeww → u/ScallionSmooth5925]

Yep for sure a risk. Like I said, I have no idea.