Third owner, first time owner

[mrpilotron]

I am buying a scratch-built legacy Sonex that was finished in 2014, sold to owner 2 earlier this year, then resold again. I'm not new to flying light airplanes, but new to the Sonex line. I logged some EAA chapter build time working on a Zenith, I'm a member of an RV-12 flying club, and have been involved in the maintenance and upkeep for several airplanes in the past. I cannot claim to be an experienced builder, but I am also not a total newb. I have lurked here for several months and spent more time than I'd care to admit reading back through this and other forums for several months to make sure I know what I'm getting into.

The plane I'm buying is definitely not a pristine show plane and the amateur nature of the build shows in several non-critical areas. Attention to detail and obsession about making parts look like factory CNC production was not the builder's goal. The pre-buy inspection revealed several areas that require attention before I'll be comfortable taking it for more than a test-flight around the pattern. This is not to say it's a bad build, but just being realistic about what it is. Perhaps more important is to be realistic about what it is NOT. The aircraft is airworthy and structurally sound. Edge distances for rivets are correct, the spar is properly constructed, and the AeroVee 80hp engine runs great. The 54/44 Sensenich prop looks brand new.

My concerns and plans to fix them are:
1) The brakes were unable to hold against even an 1800 RPM runup. I know the factory says you really don't need brakes, but I do need to do a proper runup and I prefer not to do it while accelerating down the taxiway. Stopping after landing used WAY more runway than I like. I could just barely feel any difference between no brakes and full effort braking. Since there was a lot of oil on the belly and gear legs, it's likely that the pads are well oiled. Once we get the plane home, I will dismantle and clean/adjust everything as much as possible. If that doesn't get significant improvement, I may drop an order for the hydraulic upgrade. I may also look into a proper caliper based disk brake system if that's not too much trouble. I welcome any advice on this subject.

2) As noted above, oil on the belly is coming from leaky pushrod tubes that the seller just replaced. His effort seems to have made a big difference, but there is still a little bit of oil weeping out of them. I'm probably just going to wipe off the drip, clean up the belly, and not worry too much about that for now.

3) Climb performance was underwhelming at best. I weigh 195 and the seller is about 170. With a 1/2 tank of gas we were pushing the upper end of the rated max. Our estimated T.O. weight = 1070 subject to a lot of assumptions and a little science. I need to do a new W/B measurement with calibrated scales because it was just freshly painted. We used well over 2k feet of runway and rotated at about 75 mph. The engine was turning between 3200 and 3300. Climb put us above the trees at about the 4000 foot mark and we were probably 100 feet above them as we left the airport property. We flew an abbreviated pattern much closer in than the standard Cessna training flight would do. I'm not sure we made it more than 400 feet high in our little trip around the patch, but I forgot to look at the altimeter while I was admiring the patchy fog spots glowing in the first light of dawn. Landing approach came down quickly as soon as power was reduced. It felt like he came in a little hot with quite a bit of throttle still applied, then pulled power and floated a long way before touching down. We used over 4000 feet of runway due to the previously mentioned lack of brakes. My conclusion from that flight is that this is a great single-seat airplane, but it really needs the turbo upgrade to be a usable 2-seat plane. Turbo kits are currently enjoying the same delays as everything else: 4 months. Not sure about the prop that needs to go with the turbo.

4) There is something wrong with the starter ring gear. He had to rotate the prop by hand to a place the starter would bite and spin the prop. I expect to replace the ring gear, but I'm not sure why it has this problem in the first place. The engine only has 65 hours on it so I suspect an alignment problem. This will be one of the first things that gets fixed once we have it home.

5) Age has done what it does to both fuel lines and the canopy. I will replace all the fuel lines while I have the engine off for the starter gear replacement. I might do the canopy too. There are several spiderweb cracks around bolt holes and some yellowing from age.

Overall, I am happy to get started with this project. I love tinkering and building stuff so buying a plane with known problems is not a scary thing to me. I'm sure I'll spend a lot of time with my friendly local EAA technical counselors. Due to the known issues, we are removing the wings and trailering it home.

[Bryan Cotton]

Welcome to the forum! I'm about 200 lbs and am happy with the climb performance flying single place. Up soon is ballasting to max gross, we will see if I'm still happy.

Be sure to check out the "in search of the elusive dry Aerovee" thread :
viewtopic.php?f=7&t=4030

[GraemeSmith]

Dupe post removed

[GraemeSmith]

Welcome!

I'm a non-builder / second owner of a Legacy Sonex with Aerovee. I've put 350 hours on it since I bought it from the builder 30 months ago including a top overhaul just shy of 500 hours. Couple of 1600 mile cross countries and a lot of local stuff. See this trip report from this summer that includes some notes about managing the AeroVee in hot weather.

viewtopic.php?f=17&t=6884

The plane I'm buying is definitely not a pristine show plane

Mine lives in the tie downs. It looks nice about once a year after a big polish - otherwise it looks clean. It is a "working" plane.

1) The brakes were unable to hold against even an 1800 RPM runup.

If it is the stock brake shoes and drums with a single wire system. Pull the drums and check the shoes have any friction material on them. Replace as necessary. Make SURE the drums are in round with the wheels to avoid them snatching if running with any eccentricity. Snatching will strip brake material off these fairly cheap shoes in a heartbeat. Then adjust wire to tighten the system and slightly preload the wire - just enough that the brakes are just off working. This will hold the plane on an 1,800rpm run up - till they won't and you have to tighten the wires again as the shoes wear. Oil inside the drums is a little unusual.

2) As noted above, oil on the belly is coming from leaky pushrod tubes that the seller just replaced.

See the thread Bryan mentioned about trying to get an AeroVee absolutely tight. Good Luck....... :-)

3) Climb performance was underwhelming at best.

The plane with an AeroVee is NOT a homesick angel. I plan on 1,800ft at maximum gross on a standard day. If the DA is higher expect to use more. 500ft per minute if it is a standard day. On the trip above I was using 5,000ft runways for safety (3,000 used in high DA's of 4,000ft or so) and expecting 2-300ft per minute if things were cool.

Landing approach came down quickly as soon as power was reduced. It felt like he came in a little hot with quite a bit of throttle still applied, then pulled power and floated a long way before touching down. We used over 4000 feet of runway due to the previously mentioned lack of brakes.

Standard day - coming in over the threshold JUST off a stall and touching down - I will use 1,000ft most days and 1,500 to 1,800 at maximum gross if I am being gentle with the brakes. You can stop shorter - but it's tough on the brakes. Took me at least 40-50 landings before I dialed it in.

Not sure about the prop that needs to go with the turbo.

At least with the Prince P-Tip - it's a different prop for the turbo compared to non-turbo.

4) There is something wrong with the starter ring gear. He had to rotate the prop by hand to a place the starter would bite and spin the prop. I expect to replace the ring gear, but I'm not sure why it has this problem in the first place. The engine only has 65 hours on it so I suspect an alignment problem.

If the engine is good shape and the prop correctly installed the engine will stop with the prop horizontal. 50/50 chance as to which way it stops. So there are just two locations on the ring gear that will present to the starter. 180 out from each other. If the ring is chipped (sounds like it is) then you have a 50/50 chance of stopping on the chip. Flipping the prop over 180 will get you on the non-chip for a start. But as the starter whirls a chipped ring gear then things will deteriorate fairly quickly and you will keep losing teeth near the first lost tooth. Sounds like he was fiddling to get to some good teeth. There is a thread on here somewhere about a starter fitted TOO in mesh when engaged which causes gears to chip.

5) Age has done what it does to both fuel lines and the canopy. I will replace all the fuel lines while I have the engine off for the starter gear replacement. I might do the canopy too.

If nothing else - review:

https://www.faa.gov/documentLibrary/med ... w-chg1.pdf
Section 3 - Transparent Plastics
and consider stop drilling the spider webs or double the material A canopy disappearing in flight is "interesting" (happened to me).

[peter anson]

Good advice from Graeme. I'd like to give my own view of the brakes.
A couple of years ago my brakes had deteriorated from their already marginal performance and when I disassembled them I found that the lining was separating from one of the shoes. Shipping from the US to Australia is a significant cost so rather than buying new shoes I had the old ones relined by an automotive brake repair shop. I machined the shoes myself but I have no doubt the repair shop could have done a good job of that. The result was a dramatic improvement of the braking that I can only put down to better lining material.

I fly out of an airfield at 1650 ft AMSL with the longest runway less than 2300ft. Even before making the above improvements I never had any problems stopping in well under that distance. Is it possible that if it used 4000ft to stop that the engine idle is way too high?

It took me a long while to find a way of satisfactorily centering the brake drums because I was looking at the wrong problem but the following procedure worked well. Assemble the wheel and brake drum but with the bolts only finger tight and fit to the axle. This means you can't have pressure in the tires. Pull the brake on as you rotate the wheel and it will tend to push the drum into the centered position. Remove the wheel and tighten the bolts.

Peter

[Bryan Cotton]

I've got the Aerobrakes. I typically do my runup in the grass at 2000 RPM and don't creep. On hardtop I generally will creep.

[Matt541]

Welcome from a 4th owner!

The climb rate with 80hp REALLY surprised me as well. No big deal out in the flat lands, but some increased pucker factor in an area like mine with rising terrain. (Lots of fun after getting to altitude though!) Pay attention to that DA as well. No personal experience, but from research and observation it seems 100hp is the minimum if climb performance is a concern. Sounds like the OWW is getting some good #s with the 912is, has me thinking...

I'm using the O'Keefe Hydraulic brakes with a stick mounted master cylinder and a velcro cable tie strip to hold it during run up or stronger. Works great, no creep. (I don't recommend that method as a parking brake though.)

Be sure to check the pitot/ static lines as well, I recently found a section under the panel that cracked apart in multiple locations.

Best to not take a chance on the canopy. I didn't have a choice but to replace mine, takes a while and is a little finicky, but definitely adds to peace of mind. I also replaced my windscreen as it had some cracking in various spots. These airplanes don't fly well if either come off.

[mrpilotron]

I'm using the O'Keefe Hydraulic brakes with a stick mounted master cylinder and a velcro cable tie strip to hold it during run up or stronger. Works great, no creep. (I don't recommend that method as a parking brake though.)

Best to not take a chance on the canopy. ....

Please tell me more about the O'Keefe brakes. I have no patience for pathetic brake performance and since I'm taking it all apart anyway I might as well make it work GREAT rather than just better.

Good points on the canopy and windscreen. It's cheap insurance to replace it now.

[DCASonex]

The O'Keeffe brakes were originally made and sold by Great Plains, put that operation was sold to O'keefe a few years ago. My installation of those on a Sonex can be found here:
https://sonexfoundation.com/the-amsler-files
scroll down to the end for section on wheels and brakes.
David A.

[GraemeSmith]

I have no patience for pathetic brake performance and since I'm taking it all apart anyway I might as well make it work GREAT rather than just better.

Just don't nose her over!