Crack in prop

[m chaussettes]

My flight instructor told me that the one single emergency that one should just put their head between their legs and say Sayonara is if a part of the prop goes. Usually, that will cause the engine to tear itself off the mounts in less than a second. So yeah, it's not worth a few bucks to keep a prop you even think might be hinky.

 

[Slade]

I managed to clip a tree using quickshots. Luckily the drone recovered itself, at first I thought it lost signal but upon inspecting the footage later at night it seemed to have clipped a tree and one of the props has a crack. I didn't see the crack on that day and continued flying and it flew fine. I don't have any spare props with me and need to fly, is it a no no to fly with one cracked prop?

The Mavics are phenomenal aerial platforms that control a large and complex number of parts. A cracked or chipped propeller simply reduces the quads abilities. Why take the chance of a catastrophic failure? Just my two cents worth. ??

 

[julius13]

Just don't fly with a cracked prop. Period. I'd be more worried about a serious accident than worrying about losing the drone. You can get new props fast from Amazon vendors. Or if you are in the US and near civilization, try Best Buy. They keep a pretty good stock of propellers at least at the store near me. Good Luck.

 

[Shon]

Just don't fly with a cracked prop. Period. I'd be more worried about a serious accident than worrying about losing the drone. You can get new props fast from Amazon vendors. Or if you are in the US and near civilization, try Best Buy. They keep a pretty good stock of propellers at least at the store near me. Good Luck.

Read a thread recently where someone was in India. They contacted a shop some distance away ( a couple of hours). and the shop sent someone out to their hotel with replacement props.

 

[msinger]

Usually, that will cause the engine to tear itself off the mounts in less than a second.

That probably wouldn't happen. The aircraft would drop like a rock though.

 

[WithTheBirds]

That probably wouldn't happen. The aircraft would drop like a rock though.

Drop like a rock? Why? It seems from history that numerous aircraft manage to land successfully with complete power loss.

Its not hard to appreciate how loosing a significant part of a propellor would lead to serious imbalance and vibration. Many Jet Aircraft have shear pins which allow for an engine to detach rather than destroy the wing- it is obviously a real problem.

 

[old man mavic]

Drop like a rock? Why? It seems from history that numerous aircraft manage to land successfully with complete power loss.

Its not hard to appreciate how loosing a significant part of a propellor would lead to serious imbalance and vibration. Many Jet Aircraft have shear pins which allow for an engine to detach rather than destroy the wing- it is obviously a real problem.

you know as well as the rest of us that prop failure on a drone with only 4 motors would cause it to head ground wards out of control, agreed that 6 or 8 motors will keep flying but not a mav they dont glide

 

[WithTheBirds]

you know as well as the rest of us that prop failure on a drone with only 4 motors would cause it to head ground wards out of control, agreed that 6 or 8 motors will keep flying but not a mav they dont glide

Yes- that seems to be the case for quadcopters. I am interested in the reality of the scenario where a full scale AC (fixed wing) looses part of a prop. That is the issue I responded to for clarification. Any ideas?

 

[old man mavic]

ok i see where you are coming from my mistake aircraft not drone,if the air frame was not compromised when the prop failed, then in theory given enough height it should be able to land provided a suitable place could be found in time and also how much of the prop was missing

 

[john2k]

Thanks for the replies. I'm not flying it now. I'll carry spare props next time.

 

[MAvic_South_Oz]

How can I check if hub area is damaged?

Visually inspect it for damage.

So, remove the props and inspect it or inspect the actual arm housing etc?

I would even replace a chipped prop to be sure of it working same and the others, balance etc, and in case of unseen cracks / fractures.

Yes, remove props, check visually, including the little clips that turn into the motor fixing points.

I would also lightly flex each prop, twist a bit too, and the attachment clips just to see if any flex more than usual, or any very tight cracks open up.
The little clips would move significantly under a tiny bit of pressure if slightly cracked, they are probably the most fragile part of the prop.

As I leave my props on the MP all the time, I generally don't pre check them before each flight, certainly if I clip a little branch, or even a leaf or two I would !
It might be worth getting into the pre flight check habit with them, or at least once a month . . . though you have to be certain to refit them properly, there are threads of props being lost (usually at start up) when not correctly turned into the mounts points.

The other question.
If you never touch anything with a prop, keep it secure in a case where props are protected etc, how long in time should you simply replace a set of props ?

Plastics do fatigue I guess, and while the drone is flying they are exposed to UV light which breaks down that material.

 

[Dougal McBear]

I managed to clip a tree using quickshots. Luckily the drone recovered itself, at first I thought it lost signal but upon inspecting the footage later at night it seemed to have clipped a tree and one of the props has a crack. I didn't see the crack on that day and continued flying and it flew fine. I don't have any spare props with me and need to fly, is it a no no to fly with one cracked prop?

Just carry spare props. It's about preparedness and safety.

 

[Rquirk]

I got a similar crack in a prop and it continued to fly. However on removing the prop I found one of the pegs on the hub had also broken off. I got two new props.

 

[john2k]

I got a similar crack in a prop and it continued to fly. However on removing the prop I found one of the pegs on the hub had also broken off. I got two new props.

I inspected the hub area under the props and haven't noticed anything broken or damaged. A pic below, does it look ok?

 

[msinger]

I inspected the hub area under the props and haven't noticed anything broken or damaged. A pic below, does it look ok?

The hub is the center of the prop (not the top of the motor).

 

[Drgnfli]

I got a similar crack in a prop and it continued to fly. However on removing the prop I found one of the pegs on the hub had also broken off. I got two new props.

You should have bought a lottery ticket that day... LOL! I did the same thing unknowingly after a hawk hit my MP & cracked a prop. I saw on the RC screen a "collision" but didn't know what happened. When I landed my MP, there were scratches all over the battery & arms & one prop was cracked. Thank God for tough plastic!

 

[m chaussettes]

That probably wouldn't happen. The aircraft would drop like a rock though.

It really does happen.

 

[jeplane]

That probably wouldn't happen. The aircraft would drop like a rock though.

Not quite.
Planes do not drop like a rock, litteraly that is.
Granted, the space shuttle was descending at a 1:1 glide ratio, so it would be pretty close!…

Single engines drop at about 9:1 glide ratio. Gliders and airliners at around 30:1. So you have miles to go before the site of the crash.

If a blade has cracked, or worse “flies of” the hub, it is true that the vibrations will be so severe that a pilot would no longer be able to read the instruments, and the engine mount can actually separate. When that happens, I wouldn’t want to be in this guy’s shoes. The best is to shutdown the engine IMMEDIATELY and become a glider.

In the case of a drone, a missing blade or a crack in it means loss of control flight, up to total loss of the hull.

 

[Drgnfli]

In the case of a drone, a missing blade or a crack in it means loss of control flight, up to total loss of the hull.
[/QUOTE]

No! I had a hawk attack my MP & the bird left scratch marks all over the top of my MP & cracked one of the props. The crack was about halfway through the thickest part of the prop. Luckily, I was able to bring it back home with no loss of flight control. I often wonder what those props did to that hawk's legs...

 

[jeplane]

And then we have the lucky ones.....