Prop failure....... Have you had one??

[Jetpainter]

Ouch!

 

[Komet163]

I heard a full size Lancair 4p have one disengrate on the runway as he powered up for takeoff, luckily he had not released brakes yet. Sounded like a cannon blast talked to pilot said it was hard to even taxi it was shaking so bad, came to find out he had hit a plastic cone as he taxied out. He was lucky that day. Composite fuse and wings radiographer and engine torn down before it could fly agian

 

[tylerzx9r]

Damn!

That is what I said, and I do not cuss!

 

[Naughty Monkey]

It looks like the prop bolt hole lined up with the wood grain and the piece just slid out. Almost looks like it was cut out.

 

[Snoopy1]

Terry I have to agree with you if the hub was still on and tight and one blade missing and you running around 8000 RPM that will disassembled an aeroplane every time. Do the calculations if we know the out of balance weight it would be quite a large number.

 

[Snoopy1]

Looking through all the pictures this was a well designed plane. And the strength well distributed. The plane damage was everywhere. If the plane had been over designed in fuse and motor box week it would of just sheared the box and be over with. I must say that I have seen this a few times with carbon back plates.

 

[49dimes]

Hey!.....I think a monkey figured this one out!

Looks like a compression crack may have started at that bolt hole and of course the rest is history. And as far as unbalanced rotating mass......I have seen steam turbine rotors break through and lift off turbine casing covers weighing 1000's of pounds and steel 2" thick.

 

[cardenflyer]

This must have been the first plane you put together or something. Jeeze. Haha, you couldn't tell the difference from a worn in 50 or this 85 shaking on the ground. Just sounded sweet. I was telling him to put dle 55 on the cowl and play it off like he had the world's best dle 55 a few flights before this.

This is why dad was always so intense on teaching me to never stand down the line of the prop ever. This can happen. Sorry man.

 

[yakken]

Never had a prop actually destruct from operating loads. Will be interesting to hear. Like you, I run mainly carbon.

I am wondering if it could be wood quality/durability. Like a grain pattern that is erratic or just a bad piece of wood that slipped through the cracks and got made in to a model prop. Got a pic of what's left? From what I know about sonic force and harmonic vibration maybe there was a frequency being generated by the operation that happened to coincide with the frequency of resonance of the wood material in the prop. Like when a singer shatters glass by proper amplitude, harmonic and pitch.

You just break them when they fall off the stand [emoji12]

 

[Terryscustom]

This is why dad was always so intense on teaching me to never stand down the line of the prop ever. This can happen. Sorry man.

I've seen videos of people running up engines while in front of them, or with people in line with the prop arc. Sends shivers up my spine.