Jump to content

A bad day for my prop


ohdub

Recommended Posts

This morning I was making the short flight over to the M20Doc's shop for some minor maintenance. When I arrived, I was still sitting in the airplane organizing my things when Clarence walked out and I heard him gasp - my heart almost stopped, I looked up and saw what he was looking at, a good chunk missing from my prop. On departure my prop must have picked up a pebble, I've seen many small dings in props before but nothing like this. 

 

 

20180323_110125.jpg

20180323_110132.jpg

  • Sad 1
Link to comment
Share on other sites

Wow.   It must have been one big pebble.   I'm wondering with something that significant, are you in sudden stoppage territory?  The Lycoming bulletin states "Any incident, whether or not the engine is operating, where repair of the propeller is necessary"

Link to comment
Share on other sites

29 minutes ago, chrisk said:

Wow.   It must have been one big pebble.   I'm wondering with something that significant, are you in sudden stoppage territory?  The Lycoming bulletin states "Any incident, whether or not the engine is operating, where repair of the propeller is necessary"

The engine will require an inspection.

Link to comment
Share on other sites

Wow! I’ve bever seen something like this! Glad it held up for you to be safely on the ground. Was it FOD? Or was it a nick that developed into a crack which ran and stressed it to the point of failure? 

 

 

Link to comment
Share on other sites

Per AD 2004-10-14, this damage meets the definition of a “Propeller strike”

(i) For the purposes of this AD, a propeller strike is defined as follows:

(1) Any incident, whether or not the engine is operating, that requires repair to the propeller other than minor dressing of the blades.

The propeller will need repair/overhaul and the engine will need the crankshaft gear retaining bolt and lock plate replaced per Lycoming SB 475C.

Clarence

Link to comment
Share on other sites

That's not pebble damage, that's a bolt.  A pebble would shatter and move out of the way before it displaced that much metal, a stone with enough mass to do that would have left a wider mark.  The only thing small enough and stout enough to take that deep a bite has to be steel.

Go after the airport manager for not performing proper FOD checks on their runway.  Donno if you'll get anything out of it, but if the airport implements a FOD walkdown each day, it might at least save the next guy...

  • Like 4
  • Thanks 1
Link to comment
Share on other sites

I had to ask the Airport to please stop driving their vehicles between a gravel pile and whatever/wherever they needed gravel for across the taxiways - instead of going to the long way around to the road - and explained that the constant supply of fresh pebbles was doing a number on the props.  Very responsive now there are cones at the end of each dead end taxiway to discourage dragging gravel along. 

Some FOD you can’t do a thing about.  Some FOD is preventable.  

  • Like 1
Link to comment
Share on other sites

The vertical displacement of the fracture surface at the left and right sides of the fracture are an indication of an impact that plastically deformed the blade before the upper section of the fracture separated from the body of the blade.  I agree with ShuRugal - this was some FOD that was small in size, but had substantial mass.

Link to comment
Share on other sites

7 hours ago, ShuRugal said:

That's not pebble damage, that's a bolt.  A pebble would shatter and move out of the way before it displaced that much metal, a stone with enough mass to do that would have left a wider mark.  The only thing small enough and stout enough to take that deep a bite has to be steel.

Go after the airport manager for not performing proper FOD checks on their runway.  Donno if you'll get anything out of it, but if the airport implements a FOD walkdown each day, it might at least save the next guy...

It must be a steel bolt made of gravel as there is rock/sand debris in the bottom of the divot, it’s in my shop and I looked at it again this morning.

It would be up to the airplane insurance company to go after the airport for their loss.

Clarence

Link to comment
Share on other sites

It must be a steel bolt made of gravel as there is rock/sand debris in the bottom of the divot, it’s in my shop and I looked at it again this morning.
It would be up to the airplane insurance company to go after the airport for their loss.
Clarence
Rofl "steel bolt made of gravel". I'd've never guessed a rock could take that deep a chunk out without also taking a wider bite.

Sent from my Pixel using Tapatalk

Link to comment
Share on other sites

9 hours ago, bradp said:

I had to ask the Airport to please stop driving their vehicles between a gravel pile and whatever/wherever they needed gravel for across the taxiways - instead of going to the long way around to the road - and explained that the constant supply of fresh pebbles was doing a number on the props.  Very responsive now there are cones at the end of each dead end taxiway to discourage dragging gravel along. 

Some FOD you can’t do a thing about.  Some FOD is preventable.  

When I was a lineboy a zillion years ago our ramp was PSP (pierced steel plating) on top of gravel.   The gravel would work up through the holes and lay in the grooves in the plating.   It was one of my many jobs to constantly walk the ramp and collect the loose gravel.   My life was occasionally made miserable by the arrival of an Army Chinook or Jolly Green Giant helicopter, which would fling the gravel everywhere when they arrived or departed on the ramp.   Even though it was decades ago, and as cool as they are, I still harbor much bitterness towards Chinooks for this reason.

I also spent a lot of time helping to dress prop dings.   They were a normal thing on that ramp.

And I never saw a ding that looked anything like that one.

I hope it gets sorted out satisfactorily.

 

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.