Well, the snow's all gone and I'm back to gravel ops for the summer. And with it, the first dings in my new 8042 prop. What do you guys and gals aim for when filing out dings? Any favorite tools for the job besides just a leatherman?

Thanks, and happy rock-season to everybody.

-DP

denalipilot wrote:Any favorite tools for the job besides just a leatherman?

I wouldn't want to fly without my leatherman, for a whole lotta reasons. One of which is that the file is just perfect for props.

Gump

If it's a new prop, then it should have come with a manual that explains prop filing, damage limits etc. Be careful, you can't put metal back

a Vixon file is about the best, is will file clean and not ball up the aluminum. I think the diamond pattern on the leatherman is about the same or similar cut.

Like the man said, use care, you can't put it back.

I took a pretty good sized nock out of my prop one time, the only file available was a chainsaw fiel & it worked just dandy. In fact, thinking about it now, I just might add a chainsaw file to my airplane tool kit.

Eric

AC43-13-1B section 4 covers prop repairs. I always go over the repaired area with sand paper or planish it smooth.

I must be lucky because with all the time I spend off airport I can't remember the last time I picked up a rock with my prop.

Jason

First, there are numerous FAA types who will tell you that dressing a prop requires an A & P certificate.

I don't know if that is really true or not, but nevertheless, FIRST find a good mechanic, and have THEM SHOW you how to PROPERLY dress a prop.

It is not that hard to do more damage than good, and some PERSONAL instruction is going to go a lot farther than chit chat over the internet.

MTV

Yea, and if you really mess it up- there's always JB Weld.... fix it right back up and paint er up.... Didn't hear it from me......

mtv wrote:First, there are numerous FAA types who will tell you that dressing a prop requires an A & P certificate.
MTV

Yup, absolutely correct....so learn how to do it right, then don't brag about it on the Internet!
(Unless you're an A&P!):shock:

Rocky

[/quote]In fact, thinking about it now, I just might add a chainsaw file to my airplane tool kit.

I think I'll do the same .

Actually, instead of going into details about the type of unauthorized repairs that get done, let's hit on prevention because these damn things are expensive.
The most (not all) common reason for getting dings from gravel is a high prop speed and a stationary aircraft. Go to a gravel or dirt field field sometime and watch guys taking off. There will actually be a little twister in front of the prop sucking crap up and into the blades. I've seen a couple of guys on the home field with 1800' of runway, run the throttle up full and then release the brakes.
Two schools here, the first does one of two things, does a stationary run up or nails the throttle prior to releasing the brakes. The second does the run up while the A/C is taxiing and then on T/O allows the A/C to begin moving with partial throttle before a steady application of throttle allows it to become full throttle.
Knowing how to dress a prop in an emergency situation is important too. But a lot of these dings can be prevented. I can screw up a lot of things (You guys have no idea!) but in the last year of roughly 120 hours of maybe seeing 15% of those off paved runways, I have only had to have one ding filed out.

YELLOWMAULE wrote:Actually, instead of going into details about the type of unauthorized repairs that get done, let's hit on prevention

Well, as the author of this ill-advised thread, I appreciate the direction you just took it, YellowMaule.

Beside the rolling run-up and the gradual throttle application on takeoff, another good trick for STOL takeoffs is a J turn. Assuming you have to back-taxi to your takeoff-starting point, you can carry some speed through your turn at the head of the runway and then you are already accelerating when you complete your turn, pointed down the departure runway. Also helps to avoid any of that standing-on-the-brakes, rock-sucking agony that we've all witnessed.

-DP

Most important is for the J turn to be to the right.
Jeremy

Here's a video on field dressing of props:

http://aviationsafetyvideos.com/prop3.html

I am sure that is the shop guy that used a pipe wrench to add some twist in my 172 prop.

jgerard wrote:AC43-13-1B section 4 covers prop repairs. I always go over the repaired area with sand paper or planish it smooth.

I must be lucky because with all the time I spend off airport I can't remember the last time I picked up a rock with my prop.

Jason

I wish I had that luck, 1st time out with my new three blade scimitar prop and its got at least three dings. The thing sucks dirt 4 ft away up about 7 inches in from the tips. If I kept moving while the turbo spooled I would be at the other end of the runway before I could take off.

Another thing that I have been told, but not verified is in regard it to tip shape. I have been told that the vortise on a round tip prop will start right under the prop, where as the vortise on a square tip prop will start 4-5 foot behind the prop, possably being a little more forgiving.

FWIW Gary

One more thing to look out for is small rocks flung up onto the BACK of the prop by the tyres. One aeroplane I fly quite a bit, 90% gravel has had a bunch of this problem. On 8.50x6.00 tyres, the McCreary/Aircraft Specialty cheapo tyres have more and narrower grooves, which seem to fling more rocks, whilst the Goodyears are less a problem. On my personal aeroplane, the 26" Goodyear so-called "Tundra Tyres" ( Has ANYone successfully landed on actual Tundra? ) has smooth tread as do the excellent ABW's, so much less likely on these.

Now If I could figure out how to prevent bug-strikes from the TRAILING edge (owing to my s-l-o-w speed)

Thanks. cubscout

cubscout wrote: Has ANYone successfully landed on actual Tundra?

Yeah, lots of times.

ANYone can land on tundra, anywhere, anytime. It's being able to take-off again that takes the skill.

Gump

GumpAir wrote:

cubscout wrote: Has ANYone successfully landed on actual Tundra?

Yeah, lots of times.

ANYone can land on tundra, anywhere, anytime. It's being able to take-off again that takes the skill.

Gump

Well, I used McCreary 8:50s to land AND take off from tundra up until getting Goodyear "Blimp Tires" signed off last fall. There's tundra and then there's tundra. Pays to be able to tell the nuances from the air.

-DP