B-Model conversion

[N111YX]

That's great news, John. It was great to see you at OSH. Sorry to have been so busy and working with such short time. Keep us posted on that conversion!

[fastj22]

Received the kit today. No damage!
Did a cursory inventory.
Cowl looks great. Big improvement from the old one.
Glare shield pre-bent (correctly)
Lots of machined fiddly bits. All match laser holed.
Panel is HUGE! Compared to the A--
Aileron push rods are now aluminum tubes instead of welded steel.
Seat pan looks like its riveted to the floor stringers. Stiff but will probably need to cut access holes for stuff.
Got a complete set of plans for building an entire B-model. Replace my ratty old ones. I kinda forgot how horribly wonderful they are. Everything you need to know is there, its your puzzle to read each page 15 times to understand what they mean! Just kidding Sonex. They are fine. Just not really a step by step manual. Its been like 5 years.

Also looks like there will be little fabrication of parts, unlike my A-model was. I will also need to create a hardware order as only rivets were included.
Reading the conversion notes, basically, everything forward of the turtleneck is new. Need to graft in some splice plates to my tail cone. But looks like I can build the entire forward section except rigging and keep my plane flying. Heck, might even try to preserve the old cockpit for the EAA chapter.

My A-model has been flying since 2013 and I've helped get another Sonex finished up, but I'm like a kid at Christmas. Can't wait to start.
My plan of attack is to fully inventory the kit this week. I'm out of country for the next month which is probably good. Time to settle down.
Then start building, putting the entire forward section from F-18 to F-01. Get the B-modeled wired properly, then when I can't do much more, take the A-model down, pull the wings, the engine and graft on the new fuselage. I can probably do the windshield but not the canopy until mated. Can't do the cowl until I have the engine hung either.
Couple of other things I plan, replace my old Garmin xPonder with the Trig22 ADS-B. Add a second A/P servo to my MGL. Oh and a smoke system. Gotta have smoke. Just need to figure out how to fit in the tight spaces.
Stay tuned.
There will be a lot of spare parts from the A-model available at discount prices, if I don't create a museum piece from the old a-model.

[fastj22]

Project update.
I'm back from Antarctica and have dug into the project.
Got the seat pan all up drilled and clecoed. Side panels are mostly done too.
Its good to be back into the building mindset.

So some comments.
The conversion kit is basically everything unique to the B-model. They expect you to use common parts/assemblies that are included in the A-model kit. If you have a flying A-model, you will need to either purchase these parts, fabricate them, or harvest them from your A-model. Initially I was a bit disappointed but understand the rational. I think Sonex might make some more coin offering a couple of conversion options. One where the builder hasn't progressed beyond the tail, and one for a completed aircraft.

I'm now seeing the point where I must do major surgery on the plane. But every weekend the WX is good and I take the bird out for 30 minute yank and bank. Then work on the conversion.

[fastj22]

IMG_1668.jpg (15.69 KiB) Viewed 8475 times

Update....
Off with the old, on with the new.
I've had to pull back the vinyl to make clean rivet/bolt attachments. I'll probably pull the entire wrap off, strip the paint (which I should have done anyways), and re-wrap. Going to attack the wings next.

[NWade]

IMG_1668.jpg

Update....
Off with the old, on with the new.
I've had to pull back the vinyl to make clean rivet/bolt attachments. I'll probably pull the entire wrap off, strip the paint (which I should have done anyways), and re-wrap. Going to attack the wings next.

John - Given how far you've gotten on your conversion, I was wondering: Do you think the new B-model style of lowered seat-pan and control-yoke/push-rod arrangement could be applied to a Legacy Sonex?

I can't swing a B-model conversion, but as my bird nears completion I'm finding that I'm about 1" too tall in the torso to fit my legacy Sonex with the standard seat and a center stick. I really don't want to put in dual sticks in order to accommodate the lowered seat mod; but the B-model gets both a lowered seat _and_ the center stick, doesn't it?

Thanks,

--Noel
Sonex #1339

[fastj22]

IMG_1668.jpg

Update....
Off with the old, on with the new.
I've had to pull back the vinyl to make clean rivet/bolt attachments. I'll probably pull the entire wrap off, strip the paint (which I should have done anyways), and re-wrap. Going to attack the wings next.

John - Given how far you've gotten on your conversion, I was wondering: Do you think the new B-model style of lowered seat-pan and control-yoke/push-rod arrangement could be applied to a Legacy Sonex?

I can't swing a B-model conversion, but as my bird nears completion I'm finding that I'm about 1" too tall in the torso to fit my legacy Sonex with the standard seat and a center stick. I really don't want to put in dual sticks in order to accommodate the lowered seat mod; but the B-model gets both a lowered seat _and_ the center stick, doesn't it?

Thanks,

--Noel
Sonex #1339

Converting a standard A model seat to a lowered seat would require a fair amount of fabrication and rework. The C channels supporting the seat are smaller and the aft attach point for the pan is moved back. I could harvest the aft attach off my old A model and send it you if you'd like. Its going into the scrap heap anyways. Have you considered just flying your bird seated center with your feet on the outer pedals?

[NWade]

Converting a standard A model seat to a lowered seat would require a fair amount of fabrication and rework. The C channels supporting the seat are smaller and the aft attach point for the pan is moved back. I could harvest the aft attach off my old A model and send it you if you'd like. Its going into the scrap heap anyways. Have you considered just flying your bird seated center with your feet on the outer pedals?

John -

Thanks for the info!

If your legacy bird had the lowered seat mod then I may take you up on your very kind offer - let's see what the next couple of messages bring, and if you harvest it then let me know (here or via PM). I am happy to contribute to your beer/flying fund as a thank you! :-)

After firing off my last post (and an email to Kerry), I found photos online of the B-Model seat supports and I agree with you that it would be a lot of work to change essentially the entire lower fuselage structure (and possibly have to purchase some expensive CNC'ed control-stick parts) in order to get a B-model seat into a legacy fuselage. Drat...

As for your suggestion: I am loathe to simply sit in the middle because it effectively turns my bird into a single-seater. I want the ability to fly with my wife (who's also a pilot) and take folks up for rides. Also, I built the center-stick version specifically so I wouldn't have to have a stick between both people's legs. I got my PPL in a DA-20 and spend lots of hours in a glider cockpit, so I like having the stick in my lap for precision maneuvering. But I hate that it leaves me no lap room for a good-sized knee-board, a place to unfold charts, it can cause non-pilot passengers discomfort, it makes it a bit harder to get in and out, etc.

I tested my fit in the airplane a bunch of times during the build and never had a concern; but I never had cushions and a closed canopy before now (9 years into the process). Although my head is nowhere near the edge or top of the turtledeck/rollover structure, I'm finding that the inward curve of the canopy rubs the the corner of my skull with just a ~3/4" cushion on both the seat bottom and seat back. D'oh!

I tried scooting my tailbone forward on the seat and if I'm willing to lean back a fair amount (not unlike sitting in a glider) I can probably fit; but I'm not sure how comfortable it'll be given the lack of shoulder/neck support in a Sonex. And at 6' 1" it puts my knees up close to the bottom of the instrument panel... But I think maybe the best thing is to try some more seat-cushion tests in a more-reclined position and see if I can find a comfortable setup.

Thanks for letting me hijack your thread, and again for your kind offer!

--Noel
Sonex #1339
Cockpit nearly complete
Construction Album

[peter anson]

Hi Noel, you might not have too much of a problem. I am only 5'8" but recently took Gordon Turner for a flight in my standard seat Sonex. Looking at the photo (see link), it's hard to believe he fitted in but he did. One thing I found is that you can't have a bulky head set. I have a Bose A20 set which is pretty compact and clears the canopy easily.
https://www.instagram.com/p/BtYaWS4h6eJ/
Peter

[fastj22]

Wings have been rigged.
Thanks to Paul Vetter for coming down from Gillette WY to assist and keep me from making stupid mistakes.
The laser level failed, so went Roman with a water level. Worked great.
I will say, rigging the wings while the fuse is on saw horses and the firewall removed is much easier.
Now to disassemble everything, and start riveting. Engine mount is on order.

[GWMotley]

Nice buddy.