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KitfoxSS
03-08-2019, 03:59 AM
Not sure if this counts as a build, but it is a rebuild.

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I'm a newly minted Sport Pilot.
Just got my wings a month ago and still need to get my Tail-drag Endorsement.
So whats the story on the bird here then?

Well it's a story with a lot of history behind it.
So pull up a chair.

This particular model II was purchased as a kit in 1989.
The owners, a father and son pair, along with a friend of the son, worked on the kit.
They spent many months building the kitfox and getting it ready. And finally in 1991 it was complete. Signed off and given it's Airworthiness Cert.
It spent the next 8 years being flown and enjoyed. Now the son was the primary owner and operator of the kitfox. And he enjoyed flying it but was ready to move on.
He jumped onto the next project. A Wheeler Express.
And as that project came to its completion the kitfox sat.

He knew the kitfox was just sitting and due to size of his hanger, it had to be stored with the wings off to allow his new plane the room needed. So even if he wanted to fly the kitfox it was a hassle to put the wings back only to take them right back off. It just wasn't practical.

He decided it was probably best to sell it as he had moved up.
The friend, who had helped him build it asked if he could buy it. To which the son agreed.
This was around 2006.

The friend had the idea that he would do some minor work to it.
It would be something himself and his own son could enjoy together.

But.....

With sadness to say, his son passed in a tragic traffic accident.
The kitfox sat in his garage for almost 13 years.

Now, I need to go back a bit.
The father and son who built this plane.
Well the son had his own son. A young toddler at the time.
That child loved the plane, as he grew up in it and was in all likely hood the first plane he had ever been in.

That child, was me.
When my father sold the plane I was still at a point in my life that I had neither the means nor the resources to buy or hanger it.
But I am now into my 30's and established enough in life. Getting my wings had always been a desire of mine and I finally decided to pursue it.
But only if I would have a plane. And not just any plane. But my fathers old plane.
I approached my fathers friend and asked him. I knew it would be a very sensitive topic being that his son who he planned to fly with. Was now gone from this world.
I grew up with his son, and the loss was a deep pain for me, but nothing I'm sure as to what he, a father, felt and still feels.
I told him, I would understand if he didn't want to part with the Kitfox.
And I'm thankful he agreed after some thought on it.

So I started my exam studies and got with a flight instructor the next day.
Some time later my father and I tested the fabric on the plane. Giving it a good look over and figuring out what all would need to be done to get her in the air again.

She needs some TLC.
The hose on the fuel tank in the wing leaked onto the fabric of the passenger side. Causing the stain seen.
The engine needs to be replaced or overhauled.
she need a new prop.
Brake cylinders rebuilt, calipers rebuilt.
Instrument panel redone.
All the bolts and nuts gone through.

She has a lot of work to be done.
Work that has already started.
My poor father doesn't know how to feel.
We're tearing apart something he built over 20 years ago after all.
But we are going to put her back together in proper order.
And I'm very thankful for him to be helping.
I'd be lost without him. He's a stickler for safety and everything being done right.
Which one could not ask for better when it comes to Aviation.
I have a lot to do before she's ready to fly again.

And I will be posting our work as it progresses.

KitfoxSS
03-08-2019, 06:04 AM
Part II

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So after pulling the wings off and storing them, the plane is now resting in the garage where it will be worked on.
First step, remove the cowling. Take the doors off, Turtle deck off, and begin to dismantle the engine.
It didn't take to long to remove the exhaust, radiator, lines, and wiring connections.
We also pulled the instrument panel out at the same time.
Leaving us with this.

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The next step was to pull the fuel lines and the remaining wiring and connections from the firewall forward.
After wards the engine mount would come off.

The plan is to strip the plane down, and remove its controls for cleaning, inspection, and then reassembly and lubrication.

avidflyer
03-08-2019, 06:12 AM
Very nice write up of the beginnings of your project. I hope you have lots of fun with the rebuild and even more when you start to fly it. Welcome to the group! JImChuk

Wfahey415
03-08-2019, 06:20 AM
Interesting story. I look forward to watching your rebuild.

aviator79
03-08-2019, 11:02 AM
It sounds like there are a lot of emotions tied up in that airplane. I'm glad it's in the family and I know that all involved will love to see it fly again.

DesertFox4
03-08-2019, 11:09 AM
Welcome James and congrats on reaquiring the family Kitfox. Should be a fun project for you and your dad.
Congrats also on your Sport Pilot license. Have fun.

efwd
03-08-2019, 12:24 PM
Great full circle story. Except the accident part of course. Rebuilds are great to follow. I expect to do one myself someday since I don't expect to sell mine;) welcome!

bbs428
03-08-2019, 09:16 PM
Excellent story, full of the trials of life. I'm glad your part in this story has come full circle.
Congratz on your Sport pilot ticket! Congratz on acquiring your fathers plane!
Some might have been tempted to fly her with some band-aids and bailing wire.
Your "fix it" right attitude is to be commended.

Hope you enjoy your journey bringing the plane back to her former self and have many hours of safe, thrilling flying adventures!

All the best!

KitfoxSS
03-09-2019, 09:31 PM
Thank you all for the well wishes.
It means a lot to me.
I'm only able to work on it on the weekends but we go at it the whole time.
My grandfather comes down every few hours to see how my father and I are making out.
He helped build the plane and he enjoys seeing me tackle it now.
Its always good to be with and doing something with family.

Part III

The firewall has been removed.
The plane has been throughly washed and cleaned and we began to take apart all the control surfaces.
Some very light surface rust was evident in a few areas. So we began to disassemble and clean those items.

The original engine is a Rotax 532.
With less then 300 hours, its not a bad candidate for a rebuild.
But hasn't run in decade though most likely.
The prop was starting to delaminate when my father sold the plane. At this point it needs to be replaced.

Well it turns out, good luck and fortune has struck me.
I found a gentleman who was sitting on quite the pack of items.
This man had a Kitfox Model II that was never completed.
He ended up selling the kit, but the buyer didn't want the engine and some other items.
So I am now the proud owner of a never been used, was still in the shipping box, Rotax 582.
As well as the Exhaust, Bing Carbs, and all the engine related items that shipped from Denny Kitfox back in the early 90's.
As well...as brand new still in box, GSC propellers.

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Having dual ignition over single is worth it to me for the safety factor alone.
As well as not dealing with points ignition.
I'll be setting up and running the oil injection system as well.

KitfoxSS
03-10-2019, 07:05 PM
Part IV

A little before and after.

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Prior to any restoration work.
Light surface rust, a ding on the forward tube, and cleaning to be done.
After a little welding that was fixed. All the surface rust was treated, removed, and then the tubes were given a fresh coating.

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All the control surfaces have been removed.
Cleaned up, recoated where applicable, and lubricated. Reinstallation and it all works flawlessly.

Time to move onto the next step.
Planning the replacement of the dash.
And oh boy....has that been a doozy.
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PaulSS
03-10-2019, 10:05 PM
Is that Adobe you're using for the panel design?

I'm looking for a simple CAD-type app that I can use. I already know the layout I'd like and have drawn it to scale but I'd like to get it laid out on a CAD-type app with all measurements etc.

My main trouble is I've never used CAD before and some of the apps are way more complicated than what I need/would like.

KitfoxSS
03-11-2019, 09:46 AM
Hey Paul, Its a program called Rhinoceros 3D.
It is a CAD design program, but I'm not very fluent in it.
I'm having help from someone who is much more adept at it than I.
CAD can be a bit challenging for sure and Rhino 3D is no exception.
Its easy to mess up where your placing things in relative 3D space. But like all things it just takes practice. I believe Rhino 3D is a commercial software though, not sure what it cost to buy.

The reason my layout is being done in CAD software, is because I have access to a cnc machine that will mill out the panel for me.
And it has to be done with precision and coordinated on a 3d plane for it to know where to move the drill bit and cut and for how deep.
If you plan to cut the panel out the old fashion way, then just doing a mock layup in a paint program like Adobe or Gimp would be fine to help you figure out where to mark everything at. Just make sure to get the proper hole dimensions and square sizes to match.

Best of luck on your layout Paul.

PaulSS
03-11-2019, 08:31 PM
Thank you for your comprehensive reply and for details of the CAD app. I'm afraid you're right and think this would be more complicated than what I actually need. I just wanted to convert my true-to-scale drawing at home into a properly measured and accurate diagram. It's not a huge deal as the EuroFOX factory will do it and they'll cut my panel but it's just me and my normal impatience/too much time on my hands/love of geekery :D

KitfoxSS
03-12-2019, 01:14 PM
I'm sorry to hear it won't work out for you Paul.
If possible, you could create an adobe image in inches instead of pixels and set the size of the canvas to your instrument layout dimensions.
Then just figure the proper sizing for gauges, thats what I did as a rough start.


Part V


After many hours of tinkering, the CAD file was complete.
We fired up the CNC machine and did a test run on a piece of wood to verify everything would work.

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We found a few issues and made changes, cutting a few boards in the pursuit.
But finally, we found the perfect layout that would work.
And thus we changed out drill bits and began to cut that nice shiny piece of aluminum.

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Since that would take several hours to complete, my father watched the machine while I worked on installing the new ELT.
I ended up going for an ARTEX 345. I liked the idea of only dealing with one battery instead of the 3 that the ARK equivalent version requires.
Plus the company is less then a two hour drive from me so bonus.

I decided to mount it to the tube frame behind the seat. This way I can easily reach it by just removing the turtle deck.
The tray was easy to adel clamp in several place to the tube and is now secured and tight to the frame.

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Following that, I made a bracket/ground plane for the antenna to mount and be fitted to the tube chassis as well.
Due to the angle of the roll bars I had to give an angle to the bracket, so that the whip antenna would not hit the fabric and instead be perfectly in line with the cavity well down the tail section.

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That being done, the panel had wrapped up.
We debur'd it and mounted it up for a test fit.
It was quite the sight......until it dawn on us.
We tested every instrument.....every switch.....every item.
But somehow, three of us, forgot to test the radio for clearance.

You can guess what we found. :(

So..... I have another sheet on order to get here next weekend.
Live and learn.

KitfoxSS
03-25-2019, 12:33 AM
Part VI

Well after learning our lesson, we made the needed changes to get the radio in a spot that would work.
Once confirmed the second piece of aluminum was cut and safe to say, I have the basic layout of the dash now in order.

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The back brace has been flush mount riveted on and the only thing left is to prep it for paint.
I will be hydrodipping a design on to it later in the week.

Moving on, we started to run the new fuel line.
Aluminum tubing and some aluminum line separators to hold it in place and the result is a nice simple fuel line system that should get the job done.
The two wing tanks exit the wings and are met with fuel disconnect valves. The lines then run down into the back of the dash and T into the header tank.
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Moving on, I started to disconnect and take the brakes off.

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The plan was to rebuild the calipers and then reattach everything and bleed the brakes.
But the parts ordered ended up being the wrong ones. So It'll have to wait till next weekend.

One step at a time.

In the meantime.
Interesting thing I found in the pile of letters and build notes from 1990.
Turns out Denny Aerocraft did a test on the Model II / III Wing struts. At 1050 Gross weight. They took the struts to +14G simulated load with out issue. +15G it finally snapped.
Interesting read.

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bbs428
03-25-2019, 07:57 PM
Interesting find in the build notes. I like that you cut your panel yourself. Nice work.
Seems there is a lot of us who do things twice... :rolleyes:

I feel your pain. Onward and upward. All the best!!

KitfoxSS
04-06-2019, 07:07 PM
Part VII


Wasn't able to get much done the week prior due to family emergency.
What I did get done was rebuilding the brakes and then bleeding the calipers and filling them up with brake fluid. I put the wheels back on and now I've got fully working brakes again.

I got right back into it this week.

The instrument dash went through many days of prepping for a base coat and hydrodip.
After doing some testing on the flaperon limiter I felt comfortable in performing the hydrodip on the instrument panel.

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Hydrodipping took a little effort, and a bath tub.
And after that a little clear and some silkscreening for the artwork and the instrument panel is mostly complete.
Just needs to dry a good week before final clear coat is applied and it's ready to go.

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So while thats drying I started on putting the firewall and motor mount back on.
Cut new carpet out to fit and things are looking good.

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Next up is the drill out the old lexan side windows and replace them with new ones.
Following that is wiring instruments and electronics up. It's quickly coming together at this point. :p

DesertFox4
04-06-2019, 07:58 PM
James, the panel came out nice.👍
Hoping family will be OK.

efwd
04-06-2019, 09:23 PM
Yes that panel turned out nice. I considered doing that myself. Watched a lot of hydro dip videos but didn't do it. Neat process with beautiful results.

KitfoxSS
04-06-2019, 10:42 PM
Thank you for the well wishes and kind words.
The good lord has looked after us, and the family member is fine now and at home making a speedy recovery.

I saw the hydrodip process by chance on Youtube some time back and thought. "You know...thats really neat." After some research I figured it couldn't be too hard.
And ultimately its not very hard. It just takes a little practice. Like anything painting wise the biggest step is the prep work.
Their is a few little tricks to it but its mostly just making sure you have adequate dipping room and depth for the part. The water is a nice 80 ish degrees F.
You make a border on the film with tape. Cut 4 relief slots on the tape so the film can expand a little as it will want to. Sit film on top of water a good minute. Spray activator. Then 20 seconds later or so...dip. Their are plenty of youtube videos showing how to do it in depth.

Like I said, its not hard. Just practice with something small to get used to it first.
If you mess up the dip. Just take some acetone on a rag and it will wipe right off and leave the paint underneath fine.
Let it dry...then try to dip again. Once you've dipped, let it sit a day or so, then clear coat it to protect the design.

Jerrytex
04-10-2019, 07:54 PM
Hey James....just saw your post. Very cool! When I sent you the fabric tester, I had no clue that you were using it for such an awesome cause. So glad you got the plane back and are bringing it back to life. I'll be following your progress.

Jerry

KitfoxSS
04-21-2019, 10:17 PM
Hey Jerry!
Thanks so much again for loaning the tester.
It really helped get things rolling.


Part VIII

So the new lexan was cut, drilled, and fitted to the doors.
We then installed the regulator/rectifier and starter solenoid.

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After that we finished plumbing the fuel line from the header tank to the gascolator up to the fuel pump assembly.
Moving on we set the dash up with instruments mounted and began the chore that is wiring.

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Next step was to get the engine mounted so we could finish the wiring from the engine to the regulator. After swapping out the mounts we hoisted the new engine into place and bolted her in.

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Next step is to plumb the radiator hose and then work on connecting the carbs and throttle linkage.
Its coming along and its nice to see more and more progress as we work at it.
With some luck she'll be ready for engine break in and testing in a month or so.

KitfoxSS
05-05-2019, 05:49 PM
Part VIIII


Things continue to progress.
The Radiator has been plumbed and the throttle linkage and choke linkage has been connected.
Everything tested out good so we went ahead and filled the radiator.
Next step was to finish the ground wiring and double checking all electronics were working.
We connected the spark plugs and tested the ignition switches for "mag" checks.

After that it was a case of mounting the exhaust and then fitting the cowls to verify clearance.

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As well as measuring to see if the mounting of the external oil tank would be feasible.
Deciding we had the clearance we began to fabricate a bracket to hold the tank.
After purging the air in the line we hooked up the oil injection and moved on to the next thing.

Which in this case was the changing of the gear box. The 582 was from a Kitfox II kit that was never done. Motor was still in sealed box from the Rotax plant.
But as it turned out it was rocking a B gear box that had a service bulletin. Rotax had changed the mounting plate for the B gear box going to 6 mounting bolts instead of the former 4.
The person I bought the engine from had the retrofit kit so we went about swapping this out then filling the gear box with oil lube.
It was then time to set the prop.

Thankfully we still had the old prop which worked perfectly for all those years. So we mounted the old one momentarily to get the pitch degree from it.
We then mounted the new prop and set the pitch to the same degree as the old prop. 11 degrees in this case.

And with that....it was finally time.

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We towed it to a field and began the break in procedure.
Other than it being hot outside and dealing with hundreds of "Love bugs" (A Florida pest), the engine ran beautifully.
Following the Rotax break in procedure, when it came time to go full throttle I pulled 6400rpm static on the first push.
No need to change prop pitch at all. EGT temps were good, the water temps started to climb being it was a hot day, but running water over the radiator as called for in the Rotax break in instructions, fixed that problem.
After the break in we set the idle adjustments and I went home a very happy person.

Its been a long couple months now, but the light is at the end of the tunnel.
Within a few weeks, it'll be out at the hanger, wings fitted once more.

Ready for the real fun.

ken nougaret
05-05-2019, 06:59 PM
Looking good. You can't be far from me, because as you say the love bugs have been horrible the last 2 weekends.

KitfoxSS
05-09-2019, 09:28 PM
Hey Ken, I'm about 2 to 3 hours from you.
Yeah this is the worst I've seen in many a year.
I went flying in a Drifter earlier this week and didn't realize Love Bugs can get about 200 feet off the ground.
Taking a love bug to the forehead at about 60mph on descent is not fun. :(

KitfoxSS
05-13-2019, 11:18 PM
Part X

This week was about getting things wrapped up on the fuselage.
We sourced a check valve that we integrated into the cap on the oil tank. At low rpm (2000rpm range) the vibration was causing it to spit oil from the relief vent when the tank was near full. We needed to address that.
Then it was a matter of doing another once over and verifying all control surfaces were in proper shape and ready to go.

We finished wrapping up wiring after I replaced the EGT gauge and probes.
The old ones had seen better days and you just about live and die by the EGT in a two stroke engine. So it was best to get something I knew was new and had been factory tested for correct readings.
With everything buttoned up we began the process of putting the dash cover back on and hooking up the push to talk on the control sticks. Putting the compass in and the carpet back in.

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We put the seat pan and the cowls on. I hooked up the belts and seat covers.
The piece that had been built to go over the back part of the turtle deck area was long gone.
So we built a new one. Using some very thin board and the left over carpet we made a new backing piece.
Complete with a a little area inside to hold a few tools and a bottle of oil.

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We ran the engine again to double check that the check valve for the oil tank would work. Which it did.
And afterwards the prop bolts were re-torqued then safety wired. The spinner then attached.

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At this point other then a few little tiny things to do, the main body is finished.
The wings are the next project. And thankfully not much has to be done to them. Other then changing out the fuel tank fittings. Giving the tanks a good flush. Replacing the bolts and pins. The wings should be good to go in short order.
It won't be long and this bird will be back in a hanger on airport property awaiting her time to fly.

DesertFox4
05-14-2019, 12:01 PM
Good progress James. You will know your Kitfox again well from nose to tail and fly ever after with a heighten confidence level.

KitfoxSS
05-31-2019, 03:54 AM
Part XI

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Almost time.....

efwd
05-31-2019, 07:00 AM
hahaha, something endearing about a photo like that. Im not sure if I ever posted it but I have the same shot of my Kitfox.

KitfoxSS
07-01-2019, 09:59 PM
Part XII

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The more things change, the more they stay the same.

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Weight and balance has been done, came in at a nice 502lbs.
I've been getting a lot of taxi practice and my father has taken it up 3 times now.
He's slowly getting ready to put it through it's paces, the last 3 times were just quick up and around the pattern checking for any issues.
We were concerned the temp was running a bit hot on climb out. But found the old coolant gauge and sender were reading off. I replaced the gauge and sender and its spot on now.
In the next few weeks I'll start working on high speed taxi with the tail up and shortly after that, it'll be my time to fly.

Its been an entertaining journey thus far and I can already tell in a few years time I'll be looking to build a Speedster S7 to continue on.

efwd
07-01-2019, 10:11 PM
It is probably good advice (I appreciated it) to remember that high speed taxis frequently become first flights so be careful and be sure to be prepared. That is what John McBean told me. Awesome work, hope you enjoy it. What am I saying, you will enjoy it.

Dave S
07-02-2019, 12:19 PM
Following your ressurection of the Kitfox II has been a joy - most notable has been your dilligence and very active work getting it done in short order.

Roger that on first flights.

One of my pals at the 'port did a high speed taxi test that DID NOT result in a first flight; however, when he went to do his first flight, the wheels lifted off 20 MPH less than what his taxi test had been. He was prepared but it really sunk in after that.

Another ended up taking off on a taxi test and wasn't exactly prepared for it - however he is still with us, even if his plane isn't.

A third person testing an old homebuilt he purchased embarrassed himself by running out of gas and rolling to a stop at the middle of the active runway. Don't even want to think about the potential on that deal.

A person should be prepared for a first flight in all respects when even thinking about that first flight.

You are doing things in a safe and effective way - that's the ticket to enjoying your kitfox.:D

Thanks for sharing

KitfoxSS
07-03-2019, 03:04 AM
Thank you all again for the thoughts and comments.
When it comes time to do high speed tail up taxi, my father will be in the plane walking me through it and making sure we don't rise off the asphalt as it were.
And should we do so, he'll be able to put her back down with out issue.
Regardless of that though, I will be on my toes the whole time.

KitfoxSS
07-20-2019, 12:16 PM
Well we tried, but sadly its just too small a plane for me and him in it.
We took it up once and he went through the motions with me. Familiarizing me with the flight characteristics of the Kitfox II.
Prominently its adverse yaw. Showed me what my sight picture should be on landings and what to do with the tail up.
He wanted to be able to give me more dual instruction but we just can't fit both of us in there reasonably. So we did what was required by my insurance to cover me and he set me loose to practice.

That being said, what he was able to show me has been tremendous and for a solid week I have been doing high speed taxi's with the tail up. Must of done at least 50 of them if not more going from tail up to down and stop, to up and down back to up, and all in between. I used to drift cars when I was a little younger and I've found certain aspects of that helped ready me for keeping the tail straight.

So today, early this morning.
My father watched after giving me some sage advice as I took to the sky solo for the first time.
It was a short flight, mostly to get me comfortable with the plane and feel how it handles solo and light.
After a few circles over the airport I descended and prepared for the one thing I had no ability to practice for before doing.

Landing.

And I'm happy to say my first landing went mostly smooth.
Very slight bounce maybe a foot or so before it settled again.
All that tail up practice made getting the plane under control on the roll out so much easier and with that I had made my first landing.
I had quite the grin on my face as I taxied up to the hanger and got out.

One down, many many more to look forward to.

Thank you all for your support of me in this endeavor and the incredible resource this forum is to everyone.

efwd
07-20-2019, 12:38 PM
Awesome! Glad your moving forward with the progress. Have Fun.

bbs428
08-25-2019, 08:59 AM
Just read your thread.
It was quite the journey. I really got a feel for your project and to a safe, fun 1st flight.

Enjoy!!