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XX621
10th Jun 2008, 11:23
Very small nick appeared in the prop of the plane I group-own.

About 2 or 3 mm long, same deep.

Still safe to fly until next 50hr?

Cheers:ok:

bluechief_b
10th Jun 2008, 11:34
Difficult to say from such a basic description, how about details such as prop type, location of nick and a picture of it?

XX621
10th Jun 2008, 11:48
Difficult to say from such a basic description, how about details such as prop type, location of nick and a picture of it?

Can't recall exact prop type, but it's a light aircraft (2750lb) single engine Hartz. CS Prop. Nick is prob 3/4 toward tip on leading edge (edge which picks up the bugs?).

greenslopes
10th Jun 2008, 11:50
Find a LAME, bribe with case of beer....................nick fixed, end of story.
Don't try and file out yourself!

IO540
10th Jun 2008, 12:48
You need to get a qualified engineer to look at it. It's probably OK if within the outermost 1/4 of the blade but if it is within the innermost 1/3 that is a lot more dangerous.

In general, nicks of this depth can be 'dressed out' with a file; a lot of metal has to be removed because the prop edge has to be restored to a smooth curve to minimise sharp surface transitions which concentrate stress and could cause a crack to propagate. The filed area is then smoothed/polished with emery paper, gradually using a finer grade until it is very smooth.

A 3mm deep nick results in the removal of quite a lot of metal by the time it is done properly, and the prop should be dynamically balanced afterwards.

This is the price one pays from operating from runways/taxiways covered in stones e.g. Elstree.


Eventually the prop ends up below manufacturers limits and has to have new blades put in, or be replaced if fixed pitch - expensive!

Pilotdom
10th Jun 2008, 13:06
As IO540 has said, get an engineer to have a look and dress it.

astir 8
10th Jun 2008, 13:24
Have a look in
www.hartzellprop.com

or google "Repair metal propellers" which will give you a direct run to the right spot on the Hartzell site.

The good news is that they are talking about 3/16" as a maximum allowable nick which can be dressed out, so you should be in with a chance.

The bad news is that the permitted allowances (depth and location) on the actual prop concerned will have to be checked and then dressed out by a and signed off by a competent person

happybiker
10th Jun 2008, 14:37
[The bad news is that the permitted allowances (depth and location) on the actual prop concerned will have to be checked and then dressed out by a and signed off by a competent person]

Bad news eh! Would it be good news if the damage was assessed, dressed out and signed out by an incompetent person then?:=

Pilotdom
10th Jun 2008, 15:00
What a stupid comment to a serious thread.

XX621
10th Jun 2008, 21:23
Thanks all. Nick was classified as minor but has been very nicely dressed out by a LAME this afternoon.

Thanks to thread posters. Am now a bit more clued up on nicks!