cracked prop repair
Posted: Tue Apr 14, 2015 7:25 am
by Johns
While the Sonex was parked a relative walked into the wooden Sensenich prop and cracked the tip. It is about 3 inches long and you can wiggle it with your fingers. Can this be repaired or do I need a new one.
John
Re: cracked prop repair
Posted: Tue Apr 14, 2015 8:58 am
by GordonTurner
You replacing the relative? :x
Re: cracked prop repair
Posted: Tue Apr 14, 2015 9:09 am
by Rynoth
A question for Sensenich, but I doubt that it’s repairable. The tip is the most critical part of the prop (highest stress loads.)
cracked prop repair
Posted: Tue Apr 14, 2015 9:09 am
by Sonex1517
Just my two cents but there is no chance I would fly that prop.
Someone I know survived losing a prop in flight. He said he had vibration so violent he was afraid the engine would tear loose.
And I would also replace the relative. 
Robbie
Re: cracked prop repair
Posted: Tue Apr 14, 2015 9:29 am
by Johns
Thanks for the replies so far guys. The relative has offered to pay for a new one so I can’t get rid of him yet.
Do you think it would be a good idea to change to a glass prop as far as durability goes. Seems it might be a stronger prop.
John
Re: cracked prop repair
Posted: Tue Apr 14, 2015 10:02 am
by jmtraylor
Call Sensenich. I damaged my tip loading the plane onto a trailer. I called Sensenich and returned it to them and it was repaired and sent back within a few weeks. I can’t say that they can repair yours, but they can evaluate it and let you know. I sent pictures of the damage first and they told me no problem.
Re: cracked prop repair
Posted: Tue Apr 14, 2015 10:06 am
by radfordc
I know of one Sonex that has been flying with a repaired prop tip for several years.
Re: cracked prop repair
Posted: Tue Apr 14, 2015 5:35 pm
by radfordc
I chipped the tip of this prop, too. I decided not to fix it!
Re: cracked prop repair
Posted: Tue Apr 14, 2015 5:42 pm
by Rynoth
radfordc wrote:I chipped the tip of this prop, too. I decided not to fix it!
“chipped”??!!
Re: cracked prop repair
Posted: Tue Apr 14, 2015 7:21 pm
by Courage1st
radfordc wrote:I chipped the tip of this prop, too. I decided not to fix it!
Good call…
Re: cracked prop repair
Posted: Tue Apr 14, 2015 7:42 pm
by Bryan Cotton
Maybe you could just trim the other side to match.
Re: cracked prop repair
Posted: Tue Apr 14, 2015 8:39 pm
by fastj22
Friend of mine got caught in the departure line at AV when the Breezy crashed and closed the airport for a few hours. Everyone in line just shut down and sat next to their planes. He said he noticed a guy off in the grass just off the taxiway working on his prop and being bored, walked over to talk to him. He was hacking off the tip of his Prince P-tip with a hacksaw. Seems he had an incident taxiing through the rough and wacked off the other tip. Was just “adjusting” it so he could fly home. The guy didn’t want to talk much to my friend and so he just returned to his plane shaking his head.
Re: cracked prop repair
Posted: Wed Apr 15, 2015 4:53 pm
by Johns
Update guys, prop can’t be repaired. The crack is to big they say. So I have to order a new one which will take 6 weeks. Crap!! John
Re: cracked prop repair
Posted: Wed Apr 15, 2015 5:02 pm
by SonexN76ET
Give Prince Props a try!
Re: cracked prop repair
Posted: Wed Apr 15, 2015 6:44 pm
by ScottM-Sonex1629
Yeah give Lonnie Prince a call. He probably won’t be any quicker than 6 weeks unless he has a cancelled order waiting for sale. His lead times recently have been longer than 2x 6 weeks…do the math, not trying to bad mouth him, his props are beautiful but woefully off of promised delivery dates.
cracked prop repair
Posted: Wed Apr 15, 2015 6:49 pm
by Sonex1517
^
What he said.
Robbie Culver
Sonex 1517
Chicagoland
Tails and Wings complete - finishing fuselage.
N1517S reserved
Re: cracked prop repair
Posted: Thu Apr 16, 2015 6:30 am
by Johns
Hey guys, would going to a Prince prop be an easy swap? I am new at this.
Also which would be better elliptical or p-tip?
John
Re: cracked prop repair
Posted: Thu Apr 16, 2015 8:53 am
by MichaelFarley56
Switching from one brand of prop to another is a very simple job in execution. The hub thickness may be slightly different so you may need a different length of AN-5 bolts for a Prince but otherwise it’s pretty simple. Logic would say to contact your local FSDO and ask if going from one brand prop to another (same size and pitch) would be a “major change” and if they feel it is, you’ll need to go back into Phase 1 for at least 5 hours. Some FSDO’s will require it, some will say it’s not a “major change.”
With regards to the different models of prop Lonnie sells…I think most AeroVee owners are happy with the P-Tip prop given its ability to “flex” at high power settings and low speeds (i.e., climb) so you can get more climb rate without sacrificing cruise speed. On the other hand, I believe the elliptical is perhaps a little faster and also less expensive. It doesn’t have the “flex” the P-Tip has though. I’d call Lonnie and talk to him about it. He’s a great guy to work with!
Re: cracked prop repair
Posted: Thu Apr 16, 2015 9:13 am
by Sonerai13
MichaelFarley56 wrote:…contact your local FSDO and ask if going from one brand prop to another (same size and pitch) would be a “major change” and if they feel it is, you’ll need to go back into Phase 1 for at least 5 hours. Some FSDO’s will require it, some will say it’s not a “major change.”
Whatever the response is from the FSDO, get it in writing, or at least an email. Something more than just a verbal “OK”, especially if they say it’s not a major change. You may run into an inspector with a different opinion someday down the line, and you’ll want evidence that you checked and got an “official” answer from the FAA. The old “better to ask forgiveness than permission” does not work with the FAA.
Re: cracked prop repair
Posted: Thu Apr 16, 2015 10:06 am
by fastj22
Help me out here, how does the FAA know which prop my plane is supposed to have? Its been a few years since my AW, but I don’t remember specifying the model and serial number of the prop on the form, maybe I did. How does one specify it if they built the prop themselves?
Re: cracked prop repair
Posted: Thu Apr 16, 2015 12:22 pm
by Sonerai13
fastj22 wrote:Help me out here, how does the FAA know which prop my plane is supposed to have?
The propeller is listed on the Application for Airworthiness Certificate (FAA Form 8130-6, block 1, items 9 and 10). I went through a bunch of back and forth with the FAA a few years ago concerning airplanes that were being raced at Reno. The racers are always looking for the “edge” and change props frequently. But many of them didn’t have the proper records to record the changes. This is not something that would be caught on a “ramp check” necessarily, but if the FAA ever decided to look at your airplane in detail, it’s one more thing they can try to find that’s not right. So if you change props without following the proper procedure, you do so at your own peril.
FAA at the HQ level told me that any propeller change other than a direct replacement of the exact same make/model is considered a “major change”. FSDO inspectors in the field don’t always see it that way. So if your FSDO tells you it’s not, get that response in writing so you can prove that you checked.
Re: cracked prop repair
Posted: Thu Apr 16, 2015 2:32 pm
by kevinh
fastj22 wrote:Help me out here, how does the FAA know which prop my plane is supposed to have? … How does one specify it if they built the prop themselves?
The FAA doesn’t know this. However, if you ever had some sort of incident you or others might make statements on past maintenance etc… It is possibly a major change (see this http://www.vansairforce.com/community/showthread.php?t=81212). So even if the FAA doesn’t ‘know’ about some change you may still be required to tell them (at least to get the email that says ‘no problem’).
Putting a plane back into phase 1 and then signing it off again after the test period isn’t really that painful.
Re: cracked prop repair
Posted: Thu Apr 16, 2015 7:48 pm
by fastj22
Sonerai13 wrote:
fastj22 wrote:Help me out here, how does the FAA know which prop my plane is supposed to have?
The propeller is listed on the Application for Airworthiness Certificate (FAA Form 8130-6, block 1, items 9 and 10). I went through a bunch of back and forth with the FAA a few years ago concerning airplanes that were being raced at Reno. The racers are always looking for the “edge” and change props frequently. But many of them didn’t have the proper records to record the changes. This is not something that would be caught on a “ramp check” necessarily, but if the FAA ever decided to look at your airplane in detail, it’s one more thing they can try to find that’s not right. So if you change props without following the proper procedure, you do so at your own peril.
FAA at the HQ level told me that any propeller change other than a direct replacement of the exact same make/model is considered a “major change”. FSDO inspectors in the field don’t always see it that way. So if your FSDO tells you it’s not, get that response in writing so you can prove that you checked.
Thanks, interesting.
When I converted from nose to tail dragger, I called the FSDO and they told me to put it back in Phase 1 for 5 hours. Makes sense, however I didn’t get written confirmation. Just complied in my logs. There is no entry on the form for that configuration. But changing from a Sensenich to a Prince might get you violated if you don’t have a paper trail? That’s insane. Oh well, it is what it is.
Re: cracked prop repair
Posted: Fri Apr 17, 2015 12:33 pm
by Johns
Hi guys, just got off the phone with the fsdo and he told me the prop change had to be done by A+P seeing I don’t have a repairman certificate. I didn’t think this was the case. Thought I could do it myself. what do you think?
John
Re: cracked prop repair
Posted: Fri Apr 17, 2015 12:52 pm
by MichaelFarley56
To the best of my knowledge, modifications and alterations on an Experimental can be performed by anyone. The only time you need a Repairman’s Certificate (or an A&P) is when you’re signing off the yearly Condition Inspection.
You should be able to switch props, engines, etc. all you want (of course making sure you follow your Operating Limitations about a major change).
Sounds like your FSDO isn’t sure about the rules governing Experimentals!
Re: cracked prop repair
Posted: Fri Apr 17, 2015 1:07 pm
by GordonTurner
I don’t have time to go look this up right now, hopefully somebody will step in with reference to the actual rule, but I’m pretty sure the rule is any person can basically do anything to an EAB aircraft, possibly requiring a return to Phase 1 (I think this does, but there’s room for interpretation). Only the repairman or an AP can sign off the annual condition inspection.
Gordon, another aviator with an opinion…
Re: cracked prop repair
Posted: Fri Apr 17, 2015 3:46 pm
by Johns
Found this,
I am going to buy a used homebuilt, what work can I perform myself?
FAR Part 43 specifically states that the rules of that part do not apply to experimental, amateur-built aircraft. Therefore, any work (not just maintenance) on an experimental aircraft can be performed virtually by anyone regardless of credentials. (This does not apply to the condition inspection). Let common sense be your guide as to what maintenance you conduct yourself.
Maybe I should talk to someone else at the FSDO.
John
Re: cracked prop repair
Posted: Fri Apr 17, 2015 5:27 pm
by radfordc
Once again you’ve shown that possibly the worst thing you can do is ask the FAA for “guidance”. If they don’t know the answer they will gladly make one up for you.
Re: cracked prop repair
Posted: Wed Apr 29, 2015 12:42 pm
by Sonerai13
Johns wrote:Hi guys, just got off the phone with the fsdo and he told me the prop change had to be done by A+P seeing I don’t have a repairman certificate. I didn’t think this was the case. Thought I could do it myself. what do you think?
This is absolutely INCORRECT! There is NO requirement for an A&P to do ANYTHING on an experimental airplane except the condition inspection (if the builder does not hold the repairman certificate). The reference for this is found right at the beginning of FAR Part 43. Part 43 contains the maintenance, repair, and alteration regulations, and the first paragraph, 43.1, addresses applicability. It states (in pertinent part):
(b) This part does not apply to—
(1) Any aircraft for which the FAA has issued an experimental certificate, unless the FAA has previously issued a different kind of airworthiness certificate for that aircraft
Since an amateur-built aircraft has never held other than an experimental certificate, this regulation states that Part 43 does not apply. Thus, ANY requirement for a certificated mechanic to perform maintenance, repair, or alteration does not apply to the amateur-built aircraft. The requirement that the person performing the condition inspection hold a repairman or A&P certificate is found in the aircraft’s operating limitations, not the regulations themselves.
Your FSDO people need some education. I suggest that you talk to the maintenance department supervisor, or the FSDO manager and get this cleared up so that you (and other homebuilt aircraft owners) don’t have problems in the future. If you get resistance at the management level of the FSDO, contact the EAA Government Relations department and get them on it to get this straightened up.