Just curious as to how these aircraft are holding up over time. This month will be 28 years since the big event noted on the Sonex site:
On February 28, 1998 John Monnett lifted-off from Wittman Regional Airport in Oshkosh, WI in a completely new aircraft: Sonex serial number 1, or “SX1.
Myunn will be 14 years old this year with ~400 hours in service. I’ve been very pleased to have had no major airframe or engine issues. Maintenance has been quite routine with tires, brake pads (once with TOB), and oil & filter changes as needed. I did pull a head on the Corvair early on when carbon was preventing a valve from closing but since I’ve learned how to lean it properly and the use of Decalin that concern has vanished. I also replaced the distributor cap and rotor. Oil feed line to the fifth bearing was replaced but again that’s a maintenance issue.
I have the original canopy that last year showed a small crack in the pilots side that was stopped using the hot needle method. I also had to chase an intermittent strobe issue that turned out to be a poor crimp connection that I made.
But all of this is small stuff in all the years she’s been flying both from pavement & grass.
I was reading today about a pilot looking for a spinner for his 55 year old certified airplane and was stunned (seriously stunned) that a replacement spinner was over $7,800.00 (yes that’s correct)!
Somedays I don’t believe we really understand just how blessed we are!
So what’s your journey after the build been like? How long do you think a Sonex airframe will last?
I’m at 3.5 years and 420 hours. Most of my downtime has been AeroVee related, especially cylinder heads. The original tailwheel bracket has failed me twice. I needed to add structure under the seat sling. Original canopy and windscreen, doused in 100LL once. Lots of tires, one flat. Had to replace the mini rudder hinge, but my fault as I accidentally used the rolled hinge instead of the extruded ones specified. I have a hard time keeping the lower motor mount to firewall flush screws tight. Looking forward to earning the 1000 hour prop tag at Oshkosh.
Not much down time; rebuilt the cylinder heads 3X, replaced the electronic ignition coils due to one failed at 350 hours, 2X new tires, all system batteries replaced at 10 yrs, small canopy crack 1” developed on the rear passenger side at 300 hours emanating from frame mounting screw - stop drilled.
All in all has been very reliable and looking forward to hearing from high time Sonex Aerovee fliers to see what we can expect getting to 1000+ hours.
Just sold my Sonex in Nov. of last year. First flight July 2012, about 588 total hours, Jabiru 3300 replaced by CAMit 3300 hours at about 150 hour mark. Original canopy cracked one day after installation, Todd’s canopy has been in use since first flight, no cracks.
Legacy/Rotax 912ULS - currently doing 200 hr service. Canopy cracked within 200 hrs. Attempt at repair, caused more cracking (my fault). Exploring Australian made preshaped/oven replasement.
Just crossed 500 hours after a little over 10 years. Had an AeroVee turbo originally. That was a disappointment. Replaced it with a Jabiru 3300 Gen 4 and love it. The engine also had some early pains but Jabiru took care of me.
on my second canopy and this one also now has small cracks that I stop drilled.
overall this is exactly what I expected. And it leaves me with a smile every single flight.
Sonex A SG DS serial #0525 kit here, purchased end 2002. Construction begun march 2003. First flight was may 5, 2005. Hobbs presently shows apprx 650 hrs.
Presently it is on its third engine- the first was a new gen 2 Jab 80 HP with which the plane was underpowered, especially on grass fields, the second was a pre owned gen 2 Jab 120 HP, which after a while started consuming oil to an alarming degree. Had it been possible to source critical components such as new cylinders and pistons, I would have kept it- however Jab ceased production of these critical items because they tooled up for the gen 4 series (I was told). Present engine is a 123 HP EP915ECI, which has been sitting in the airframe for 5 seasons and 150 hrs; so far absolutely no issues.
All these years (20!) the airframe has been essentially trouble free: only issues that required immediate attention were fractured gear leg retaining bolts (se the Sonex SB), a cracked engine attachment stud in the 120 HP mount (see another Sonex SB), and a cracked weld in the tailwheel spring attachment bracket.
The plane is presently sitting in the hangar waiting for the subzero temps and the snow to go away- I am too old to freeze up there!
I am running a fp Sensenich two-blade up front (it looks scary!). Home field elevation is 38 feet amsl.
On a standard day atmospheric conditions, with this prop I get wot static 5050 rpm and 29.5 in Hg mp. During the t/o run, it torques to the left like there is no tomorrow: full right rudder and aileron! If I flog it a little, there is no problem to get 1500 ft/min on the vsi. I cruise the thing att 4800 rpm and 22-23 in Hg mp. At 3000 ft the asi will then show 125-130 kts. Flat out same altitude the engine gradually increases to 5800 rpm (I then always forget to check the mp gauge…..), with the asi showing 156 kts.
At that airspeed the plane is rock hard in the air But I am still running the original canopy, albeit with a few minor cracks down at the corners.
And-pray tell: what is the hot needle method for canopy repair?
I used the stop drill method with good success on my first Sonex.
On this plane I decided to try something different. I read of using a hot needle to make a small hole at the end of the crack to stop the crack from spreading. It was actually very simple but I had a helper. I took a small needle (it was a tiny nail) and held it with vise grips. My helper had a propane torch and we heated the nail and then I pushed it through making a tiny hole at the end of the crack.
It is said that this is better as is melts the Plexiglas and that prevents the crack from starting again. It is quite important to be certain that you are at the very end of the crack. Sometimes the end can be difficult to see. After doing this mine has been good even after flying off of some rough and bumpy grass fields.
Perhaps I should make a video about this as I didn’t find one on the tube …
First flight January 2015.
But I am still running the original canopy, albeit with a few minor cracks down at the corners.