Aussie Experimental Supercub build

G'day guys and girls,

Been lurking here for a long time and figured as my project begins its probably time to say hello, and start a thread where maybe I can extract some tips and tricks from those with the experience.
I was offered a Supercub (originally N19BC) wreck that had been brought into Aus a few years back that I decided to grab. This started the journey into building ourselves a machine as affordably as we could, without hopefully missing out on some of the cool stuff we would love to have.
The fuse is straight and has had most all of the Alaskan mods done, float fittings and extended baggage and paint. We have a low time set of 'Back Country' wings from Col Goldsworthy's cub that are in great condition with big fuel tanks that are more or less ready to bolt on. Also, just lately I was able to acquire a nicely priced 320-b2c from a Robinson roll over with low time that is almost finished being bulk stripped. It will be mounted via an Airframes Alaska mount with the thrustline mod built in. Lightweight starter and E-mags are on the cards.
Plans are for oversized tail feathers, standard gear with 31's (until I can afford to go with the extended gear) and a baby bushweel on the business end, Dynon HDX in the panel, firewall mounted battery (dual batteries if i can fit them but I'm not sure yet), inertia reel harnesses and LED light bars all over the place (I'm scared of the dark...), electric trim if i can find a fairly painless solution. Also, at this stage Stewarts covering is I think the plan.

Some things I haven't decided on yet:
- Which wing struts - I want to run as close to the 2400lb gross weight that the wings are built for as I can with an original 18 fuse albeit modified.
- Prop - I like catto's gear. I also like the sound of the whirlwind. Not sure yet.
- Fuel delivery system - Have been looking at Rotec's TBI system and would love to hear anyones feedback on them. Failing that I'll probably just go with a carb (I think P/no: 10-3678-32 sounds like the go but would love to hear opinions) Also, going to go without header tanks at this stage as I can't really see any downsides.

Right now my next decision is around the carb/throttle body injection setup. The Rotec system on face value looks great and makes sense but I have read on the Vans forum of guys who had issues. This was an old thread though and not much has been written about it since. It is also much cheaper than buying a rebuilt carb out of the USA and having it sent over, and much quicker too. If its as good as Rotec say it is then its a no brainer but I'd love some real world feedback.

Once I work out how, I will add some photos of the bits and pieces we have and hopefully carry on with the thread as the old girl comes back to life. Also, if anyone on the off chance had any history on the aircraft I'd love to know where it came from.

Kind Regards

Adam

This will tell you it came from Oklahoma and who owned it: https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=19bc Also you can order the CD records from the FAA which may tell you more than the records you have on hand.

My opinion is with 31" tires you will not need extended gear since they both do the same thing, raise the nose.

Prop- Catto makes great props. What if you don't like the pitch you get? Do you want to send it back to the States to get it repitched? I'd get the Whirlwind ground adjustable.

The Sensenich Ground adjustable prop is one to consider.

Gday again gents.

Finally, twelve months later, I have in my shed a bare fuse, a set of wings, an engine that has been bulk stripped and various old parts that I will try and use as many of as I safely can.

This weekend I have an NDT tech coming to X-ray and test the fuselage for piece of mind before I start building on it. I’ll be taking the kids flying in this one day soon hopefully and I’ve decided that it’s cheap insurance. He has suggested the following:

What I propose:
Perform radiography of the tail lower frames for corrosion & Magnetic particle inspection of wing, strut & landing gear attach points / welds for cracking.
-This is fairly common on aircraft like your Cub and we get a good indication of an airframes structural integrity.

Anyone care to suggest anything else I should have him do while I’m here? Any problem spots that might catch me on an older frame? He’s also going to X-ray the lift struts that I have here. I have 3 sets of front and rear that are second hand sealed struts that I would like to have as an option. I may still go with new ones, we will see…

Also, for anyone interested, I have decided to go with Fly EFII electronic ignition and injection for the 320. I visited Robert in LA on a stopover in May and was very impressed with both him and his work. Like anything it has its pros and cons, but I very much liked the engine management system and decided to give it a go. It will mean a second battery and possibly a backup alternator for good measure, but it was cheaper than carbs and mags and appealed to my PT6 driving side. The old school guys might rag on me for it but I can take it ��

skywagon8a said:

My opinion is with 31" tires you will not need extended gear since they both do the same thing, raise the nose.

Click to expand...

Is here any extended gear that does not move the axles forward?

Most extended gear does not move the axles forward. If it does it should be noted in the description. 3X3 gear from Cub Crafters vs 3 in gear from Airframes. Axle width will vary from Manufacture to Manufacture also.
DENNY

crophopper said:

Gday again gents.

Finally, twelve months later, I have in my shed a bare fuse, a set of wings, an engine that has been bulk stripped and various old parts that I will try and use as many of as I safely can.

This weekend I have an NDT tech coming to X-ray and test the fuselage for piece of mind before I start building on it. I’ll be taking the kids flying in this one day soon hopefully and I’ve decided that it’s cheap insurance. He has suggested the following:

What I propose:
Perform radiography of the tail lower frames for corrosion & Magnetic particle inspection of wing, strut & landing gear attach points / welds for cracking.
-This is fairly common on aircraft like your Cub and we get a good indication of an airframes structural integrity.

Anyone care to suggest anything else I should have him do while I’m here? Any problem spots that might catch me on an older frame? He’s also going to X-ray the lift struts that I have here. I have 3 sets of front and rear that are second hand sealed struts that I would like to have as an option. I may still go with new ones, we will see…

Click to expand...

Hi CropHopper, thanks for keeping us informed of your progress.
Just out of curiosity, is getting an NDT inspection expensive?
Not sure of the process, but is the x-ray inspection fairly common and mobile over there?

Gday Randy,

The NDT work on the airframe is about $2500 AUD, so I suppose about $1500 USD. I don’t think it’s overly common on general aviation machines like this but I know of some Ag machines that have mag spec and eddy current testing requirements. Im away water bombing currently so I won’t get to see the work carried out on my fuse but it sounds as if the equipment is quite mobile, he just needs a bay in my shed at home and some electricity. I’ll see if I can pull some pics from my security cam when he gets working so we can see what it looks like.

finally worked out how to attach some pictures.

cheers

Adam

Away from home this month firebombing, but the X-ray guy visited my place last week and did his MPI on the wing/strut/gear/engine attach points and xrayed the aft section of the frame. Thankfully he found nothing of concern, with only some very minor indication of corrosion in the aft tubes. $2000 was cheap for the piece of mind for when I load the family into the old girl, so I’m happy.