New E-Prop install

[FlyingMonkey]

24 minutes ago, BugBuster (BB) said:

The way I understand it the placarded manufacturer of an ELSA has a hand in prescribing flight testing to the builder with FAA approval. The builder applies thru a local FSDO for a test area and flies off the prescribed hours and annotates the aircraft logbook the results before Phase 2 which is basically - continuance of airworthiness. I don’t get the rationale that others did it and therefore it must be OK writ large for ELSA….IMHO if whatever changes on any airplane by whomever contributes to an accident then what’s the placarded manufactures position?

The primary reasons for testing are to ensure that the change does not bring the airplane out of LSA compliance, and that it's safe.  If the manufacturer has already approved a similar change to identical airplanes, then the safety and LSA compliance of the change are already established.  If that information is provided to the FAA, they may waive a test period requirement, or shorten it to basic flight testing of a particular installation (1-3 hours instead of 5 hours).

In other words, there's no need to reinvent the wheel and test a configuration that has already received extensive testing by a manufacturer.  The correct installation on a particular airplane is all that needs to happen.  Of course that all depends on the FSDO and approving FAA official.  Here in ATL Mr. Newcomer handles these requests, and he's a two-time RV builder and very friendly toward builders and experimental owners.  I expect on a factory-approved prop change he would require a one hour test flight period...basically a single test flight to ensure proper installation. Other FSDOs or officials might have different ideas.

The factory manufacture is out of the process entirely on ELSAs.

Does that make sense?

[Tom Baker]

1 hour ago, BugBuster (BB) said:

The way I understand it the placarded manufacturer of an ELSA has a hand in prescribing flight testing to the builder with FAA approval. The builder applies thru a local FSDO for a test area and flies off the prescribed hours and annotates the aircraft logbook the results before Phase 2 which is basically - continuance of airworthiness. I don’t get the rationale that others did it and therefore it must be OK writ large for ELSA….IMHO if whatever changes on any airplane by whomever contributes to an accident then what’s the placarded manufactures position?

There are three types of ELSA aircraft. The first was the old fat or two seat ultralight aircraft that were grandfathered in. They were previously flying, and did not require a flight test period. Second is the ELSA built from a kit. These are an exact copy of a ASTM compliant designed and built by the manufacture who sells the kits. They have a required flight test procedure set by the manufacture. Thirdly is the SLSA that is converted to ELSA. These like the first group are already flying aircraft that are proven, and there is nor prescribed flight test. The question that arises is when a major change is made what is the flight test procedure. From what I have experienced in the past with EAB aircraft is that the FAA inspector has some leeway in what they want to impose based on their knowledge or lack there of what you are doing.

[FlyingMonkey]

15 minutes ago, Tom Baker said:

The question that arises is when a major change is made what is the flight test procedure. From what I have experienced in the past with EAB aircraft is that the FAA inspector has some leeway in what they want to impose based on their knowledge or lack there of what you are doing.

That matches my observations.  My big question at this point is what form to use to report a major change on an E-LSA.  The FAA Aircraft Maintenance Manual is silent on it and and I can't find anything anywhere else.

[Tom Baker]

1 hour ago, FlyingMonkey said:

That matches my observations.  My big question at this point is what form to use to report a major change on an E-LSA.  The FAA Aircraft Maintenance Manual is silent on it and and I can't find anything anywhere else.

http://www.n9103d.com/about-n9103d/documents/operating-limitations.html

Look at section 10.

[airhound]

13 minutes ago, Tom Baker said:

http://www.n9103d.com/about-n9103d/documents/operating-limitations.html

Look at section 10.

Is FD liable in any way? If FD approves the prop, then an MRA since they are still placarded as the builder. Even though ELSA, they are the builder. 

[FlyingMonkey]

35 minutes ago, Tom Baker said:

http://www.n9103d.com/about-n9103d/documents/operating-limitations.html

Look at section 10.

Ah, I found a similar section in my limitations.  It says I have to notify the FSDO in writing, but does not specify use of the 8130-6 form.  Maybe I just have to write a letter describing the change?  Pic below, section 13 at the top of the page in my limitations describes the process (sparsely)...

[Tom Baker]

35 minutes ago, BugBuster (BB) said:

Is FD liable in any way? If FD approves the prop, then an MRA since they are still placarded as the builder. Even though ELSA, they are the builder. 

I think once you go experimental it removes the manufacture liability, unless of course the accept it back as a SLSA.

[Tom Baker]

4 minutes ago, FlyingMonkey said:

Ah, I found a similar section in my limitations.  It says I have to notify the FSDO in writing, but does not specify use of the 8130-6 form.  Maybe I just have to write a letter describing the change?  Pic below, section 13 at the top of the page in my limitations describes the process (sparsely)...

You don't have to notify in writing, you can call. Their response must be in writing.

[FlyingMonkey]

9 minutes ago, Tom Baker said:

You don't have to notify in writing, you can call. Their response must be in writing.

Even sweeter!

[Madhatter]

I looked at my prop today and the leading edge protection goes to the tip, my mistake. After 2 years  no damage or erosion.

[Madhatter]

I had several discussions with E-Prop in recent days. I got a small chip just behind the leading edge, most likely a spinner screw that came loose. I noticed that some screws did not have good locking threads so I now use 242 on them. Apparently this has happened before on E-Props. The chip is not an issue as is,  but can be field repaired easily with a repair kit and not noticable. The advantage of the prop without the titanium leadig edge is that it is field repairable without removing the prop. If the titanium prop gets damaged on the leading edge it is not field repairable depending on the severity. Also there is a chance the titanium leading edge could detach but never on the nanostrength leading edge. The titanium was developed for extreme conditions such as sand and very poor terrain. 

[Tom Baker]

I've been using low strength purple Loctite 222 on spinner screws for quite some time. My first CT like to have the spinner screws loosen on it for some reason.

[Madhatter]

I probably will do the same for all the screws based on your experience with the same issue,  thanks.

[Roger Lee]

Don’t use any Loctite on the standard FD spinner and backing plate screws. You’ll either strip out the screw head or cause the Rivnut to turn inside its mount. I’ve had to repair and use a Dremel to slot the head of the Allen head screw to get it out on too many.

EProp I have no experience.

[FlyingMonkey]

I remember hearing loctite was a bad idea on the factory spinner.  I check the screws for tightness every couple of flights and have not had any trouble.  I found one slightly loose screw once, but it was following maintenance and I probably didn't fully tighten it.

[Madhatter]

The E-Prop uses deep slotted screws, I think Locktight 222 is probably the way to go or slightly crimp the nuts. It's better than a gouge in a blade. I see no other alternative at this time.

[FlyingMonkey]

1 minute ago, Madhatter said:

The E-Prop uses deep slotted screws, I think Locktight 222 is probably the way to go or slightly crimp the nuts. It's better than a gouge in a blade. I see no other alternative at this time.

Yeah, it's probably necessary on the e-Props spinner, I was only talking about the FD spinner.

[Tom Baker]

1 hour ago, Roger Lee said:

Don’t use any Loctite on the standard FD spinner and backing plate screws. You’ll either strip out the screw head or cause the Rivnut to turn inside its mount. I’ve had to repair and use a Dremel to slot the head of the Allen head screw to get it out on too many.

EProp I have no experience.

The low strength purple Loctite is not an issue. No stripped heads, no twisted rivnuts, and better yet no loose or lost screws. It is simply a matter of using the right product for the job.

[Roger Lee]

I have never lost a spinner screw when torqued properly. I have even had to extract several even though they had no Loctite. They were either just over torqued or someone uses a poor Allen wrench and strips the head out. I just use a Dremel tool with a cut off blade and cut a slot in it then use a straight screwdriver.

[Madhatter]

You can only torque so much on carbon fiber. The only thing that holds a short screw is head friction if you don't have a locking nut or some sort of lock washer it may loosen over time. When a bolt is properly torqued the goal is to obtain a precalculated stretch on the bolt which holds it, this won't work on soft materials. I have several rivnuts that have lost the  locking function so locktite 222 seems to be the logical solution. If there is a better way I am open to it.

[FlyingMonkey]

If Nordlock made some thin nylon lock washers that could go under the screw heads, that might work.  I did a search and couldn't find any good nylon lock washers though.

[ls6pilot]

I bought Madhatter's old v12 e-prop. Got the pitch dialed in today at 26.5. Climb out at 70 give 5400. WOT level at 3000 ft 5500.

Previous Neuform was 5100 climb and 5650 WOT.

Very smooth compared to my old prop which was red 2 blade Neuform.

I think I will be very happy with it. Andy if you want to get together sometime before you decide to get a new prop let me know. I'm not very far away.

 

Rich

p.s. I converted to ELSA on Tuesday.

[Jim Meade]

E-Props recently changed the bolts that hold the spinner from 4mm to 5mm and mentioned there might have been a problem with non-spec 4mm bolts.  This seems to be implied in above messages.

I have not yet installed E-Props on my CTSW but it is on my Rans S-7S and flying.  I had to change the blades because the spinner came loose and marred the finish of the blade where it rubbed.  Didn't affect strength but E-Props replaced the blades and bulkhead under warranty and put new 5mm fasteners on the spinner bulkhead.

I'm adjusting my prop pitch using their protractor backed up with my Mitutoyo digital protractor.  So far, I am finding I need less pitch than the 23° they suggest as a starting point for the Rans.  (For the CTSW they suggest starting at 27°.)

They say for the Rotax to not focus on an arbitrary the propeller pitch but use whatever is needed to be sure you get 5500 RPM WOT level flight and keep the blades within 0.3° pitch of each other.

In response to my question E-Props said I can run the prop without the spinner, but it might result in some vibration.

[Madhatter]

46 minutes ago, Jim Meade said:

E-Props recently changed the bolts that hold the spinner from 4mm to 5mm and mentioned there might have been a problem with non-spec 4mm bolts.  This seems to be implied in above messages.

I have not yet installed E-Props on my CTSW but it is on my Rans S-7S and flying.  I had to change the blades because the spinner came loose and marred the finish of the blade where it rubbed.  Didn't affect strength but E-Props replaced the blades and bulkhead under warranty and put new 5mm fasteners on the spinner bulkhead.

I'm adjusting my prop pitch using their protractor backed up with my Mitutoyo digital protractor.  So far, I am finding I need less pitch than the 23° they suggest as a starting point for the Rans.  (For the CTSW they suggest starting at 27°.)

They say for the Rotax to not focus on an arbitrary the propeller pitch but use whatever is needed to be sure you get 5500 RPM WOT level flight and keep the blades within 0.3° pitch of each other.

In response to my question E-Props said I can run the prop without the spinner, but it might result in some vibration.

I have found that the spinner screws are not very secure and can loosen.  This has been an issue that I reported to them 2 yrs ago. If a screw comes out it can damage a blade which happened on my first V12 series prop.  The easy answer is to use Locktite 222 low strength sparingly on the screws,  which I have done for some time. Eventually most will loosen up a bit with repeated removal and reinstalling and the 222 is a good hedge against this. The screw size is more than adequate for a spinner, I believe the larger size screw will provide greater friction in the rivnut to retain it. 

[Jim Meade]

The story I got was the 4mm screw was not quite to tolerance and they changed to a 5mm screw for whatever reason.

They're quite specific about not using Loctite or oil, etc.,  on the bolts that have a torque spec.