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Phase 1

Scott Hersha

Well Known Member
I’ve found that during Phase 1 flight testing, this is what it is all about…….. fixing problems. My first flight, after my FAA inspection on 8/26/2022, and then fixing a fuel leak that I found that day, was on 8/31/22. This is what my plane looked like after my first flight -

View attachment 30659

I now have 6 flights logged and about 7 hours of flight time. I have an RV6 kit (now finished) that I bought used. The kit was started in 1992. I have a new O-360-A1A, standard compression, carbureted, with a carbon fiber GA fixed pitch prop, running one SureFly (left), and one new Slick mag.

First flight indicated a slightly heavy left wing, easily trimmed out with my manual roll trim system, and an elevated #1 cylinder CHT - just north of 400 until I leveled out and got some better cooling airflow and it came down below 400. What I didn’t notice, and is item #3 to be addressed is the lack of position reporting by my uAvionix Echo ADSB device - probably a setup programming error by me - more on that later. My #1 concern was the elevated CHT on #1. I cut down, then totally removed the baffle blocking plate in front of cyl #1. No noticeable effect on #1, or any other cylinder. This is what I think is happening with that #1 cylinder - the inlet duct, that basically acts as a Venturi to increase upper cowl pressure is mounted or configured too far aft on the right side, #1 cylinder. That Venturi doesn’t meet the surface of the upper cowl until it is at least 1/2 way past the #1 cylinder. That point is where the pressure rise as a result of the inlet duct will be at its maximum (almost anyway). I will be doing some surgery on that transition to make the transition end at the forward end of cyl #1. The other front cylinder - #2 - is further aft of the inlet and is my coolest cylinder. I expect at least a 30* change when I make this modification.

About the left roll tendency - I re-rigged the flaps, very slightly, to no noticeable effect. Then I re-rigged the left aileron, which made it worse. Today I un-re-rigged the left aileron, putting it back where it was before, and also slightly re-rigged the right aileron, because it was slightly off from where my measurements said it should be. I’m not at the point of squeezing trailing edges yet - a few more steps to accomplish first (I am using the Vans ‘heavy wing’ instructions). One of the things that need to be accomplished is landing gear fairings, including intersection fairings. Well, I had the lower intersection fairings installed, but the upper ones not ready for prime time yet. Yesterday when I got back from my #6 test flight, I found the aft end of my left lower intersection fairing……. missing. First time I’ve ever had a missing part on an airplane.

View attachment 30660

This is what is supposed to look like:

View attachment 30661

Basically, it became “unglued” when the landing gear flexed on landing - I’m guessing - couldn’t find any FOD on the runway. The fit was quite tight, and didn’t allow much movement, still guessing. Anyway, I’ve now removed both the forward and aft pieces of the left and right lower intersection fairings and going in a different direction with the not as cool Vans intersection fairings for the lowers. Still using the Fairings, Etc upper fairings.

View attachment 30662

View attachment 30663

I’m not sure what to do with that ‘wing’ that extends aft of the lower intx fairing on the Vans supplied piece. Not sure if it’s some sort of airflow enhancing appendage, or a speed brake. I’ve seen a couple other flying RV’s with these and they had a washer head screw and big drag inducing nut holding the back end together. Not sure I like that idea.

As far as Phase 1 issue #3 - my Echo position reporting setup. So far, in the 6 flights I’ve made, I haven’t been able to show a flight reply on FlightAware. I’m guessing I’m not outputting adequate ADSB data. I am seeing traffic on my EFIS - GRT Horizon 10.1, which controls the transponder (Sandia STX165R), and is connected directly to the Safe-Fly GPS and the Echo UAT. I’m also showing traffic on my iPhone, and my iPad mini, but I’m also showing a ghost image of me, which constantly gives me a “traffic” warning - about me! I’m sure I’ve made some sort of config programming error, but GRT is no help (they say call uAvionix), and uAvionix doesn’t answer their phone. I’ve put in a service request with uAvionix, but it takes 5 days to get a response, and who knows if that will be the answer I need. The uAvionix Echo manual has conflicting information as to programming, and I’ve followed th manual exactly like I did before on my last airplane (RV4) with EXACTLY this same system. This is what my setup looks like: (GRT Horizon 10.1, GRT Safe-Fly GPS, Echo UAT, EIS4000, all new):

8A1A6DEA-5395-457E-824D-86781994E198.jpg

E7A3427C-20B0-4580-84DD-F01CEF159E77.jpg

This is what Phase 1 is all about, right? No worries, just want to fix these issues the easiest way possible. There are several issue topics here, so if you have any suggestions about anything here, I’d appreciate any help/recommendations you may have.

Thanks
 
Well, gee. I’m too frequently puzzled as to why sometimes my linked pics work, and sometimes they don’t. I use the exact same process each time. Maybe there’s a limit to picture posting? Maybe I OD’d on pictures….
Whatever, if you have some sort of help you can offer, given the limited perspective, thanks.
 
Cooling

I heard that the #1 cylinder might need a bypass slot at the front to get air to the bottom side of the cylinder, much like the rear cylinder bypass we all are incorporating now.
 
I heard that the #1 cylinder might need a bypass slot at the front to get air to the bottom side of the cylinder, much like the rear cylinder bypass we all are incorporating now.

Thank you John. I put a bypass behind #3 (my second coolest cylinder), and also in front of #2 (my coolest cylinder). The cooling fins are not blocked in the same way on cylinders #1, and #4. I’m hoping the difference is in the inadequate pressure rise in the forward area of the right side inlet cooling duct. Guess I’ll find out.
 
As far as Phase 1 issue #3 - my Echo position reporting setup. So far, in the 6 flights I’ve made, I haven’t been able to show a flight reply on FlightAware. I’m guessing I’m not outputting adequate ADSB data. I am seeing traffic on my EFIS - GRT Horizon 10.1, which controls the transponder (Sandia STX165R), and is connected directly to the Safe-Fly GPS and the Echo UAT. I’m also showing traffic on my iPhone, and my iPad mini, but I’m also showing a ghost image of me, which constantly gives me a “traffic” warning - about me! I’m sure I’ve made some sort of config programming error, but GRT is no help (they say call uAvionix), and uAvionix doesn’t answer their phone. I’ve put in a service request with uAvionix, but it takes 5 days to get a response, and who knows if that will be the answer I need. The uAvionix Echo manual has conflicting information as to programming, and I’ve followed th manual exactly like I did before on my last airplane (RV4) with EXACTLY this same system. This is what my setup looks like: (GRT Horizon 10.1, GRT Safe-Fly GPS, Echo UAT, EIS4000, all new):

Congrats on your first several flights!

The Echo is a 978MHz UAT transmitter and those don't normally show up on FlightAware, only the 1090ES transponders do.

Submit a PAPR request for one of your flights. You will get an email back fairly quickly (several minutes to an hour or so) and you'll be able to see if your setup and the Echo is working properly.


Good luck with the rest of Phase 1!
 
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My Echo UAT shows up just fine on flightaware.
Mine does too, but it’s highly dependent on where i’m flying. In this part of the country, ADS-B ground stations can get a little sparse and that seems to make all the difference. In the northern part of the state, it’s not at all unusual that I would only get brief parts of any given flight show up on FlightAware.
 
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Most flight aware feeder stations are 1090. You can make them as 978/1090 or straight 978. Unfortunately both the dual and the 978 require a bit of knowledge beyond plug and play. Many have 978 sdrs that are actually not publishing anything because of the default configuration. I have a 978 feeder and the next closest one that is routinely active is 20ish miles away. It is about a 50 to 1 feeder ratio here in central FL. You can see the difference on Flightaware when I am close to one of those 978 stations.

As others have said, don’t trust FA use the PAPR to validate your adsb install.

If you have an old stratux receiver laying around really easy to convert to a feeder and leave at the airport. Flat lander and with the rubber duck antennas I routinely get aircraft within 25 miles and occasionally up to about 35.
 
Way to go Scott!!

Yes, phase I is a lot of checking adjusting flight data and problem solving. Like a field commissioning of a new project, making sure it meets all the requirements.

This is where the final tuning to all the issues. I made a problem sheet form with assigned number, data, etc in its own file. And worked each one until it was done. Like a regular engineering report.

Well almost all, I still have (after 230hrs) to adjust the air exit area for #4 baffle to lower the CHT by 20F. It is going to be a super pain, thus the procrastination.

Great thread.
 
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