Converting tail to tricycle gear

[Skyland field]

Just sold my 2000 Skyboy and looking for a good Sonex. Noticed almost all used ones are tail wheel.
On top of cost of the kit about how much labor cost would I be looking at if I had the conversion done?
Just looking for rough estimates.
Thanks,
Ed Nadeau

[lpaaruule]

Just a wild guess, maybe 50 hours. If you want to put a price on labor, say minimum $5000.

I'd recommend getting your tailwheel endorsment. It's a lot less work, and a lot more fun!

Sorry, this isn't the answer you're looking for

[MichaelFarley56]

Hi Ed,

Hopefully you'll some people chime in that have actually done the retrofit, but it's been done by many owners in the past. If you are planning on keeping the same engine that will help but you will need to purchase and install a new motor mount, main gear weldments, and a bunch of other small things. Depending on how the airplane and specifically the engine compartment is organized, it could be a quick and simple job or it could take a lot of work. I'd venture a guess and say anywhere between 50-150 hours is possible, along with a few thousand dollars for all of the previously mentioned parts, among others.

You'll also need a workshop or location to do the work and I'd guess you'll need to pull the wings as part of the process. A simple job but one more thing to plan on.

Best of luck!

[LarryEWaiex121]

Ed,

Considering the amount of de-construction and the amount of new parts involved, I would seriously be looking for a good used, tri-gear Sonex.
They do come up fairly often and at good prices. Or, as Michael suggested, get your endorsement and have some fun. They are a fun airplane and as tail draggers go, about the easiest to take off and land as your likely to find.
Whatever you decide, good luck.

Larry
Waiex121YX, Camit 3300, Dynon Skyview, just under 500 hrs.

[Bryan Cotton]

Here is John's post on the opposite conversion. Probably a very simar effort.
viewtopic.php?f=21&t=688

[fastj22]

Just sold my 2000 Skyboy and looking for a good Sonex. Noticed almost all used ones are tail wheel.
On top of cost of the kit about how much labor cost would I be looking at if I had the conversion done?
Just looking for rough estimates.
Thanks,
Ed Nadeau

If you are paying someone to do the conversion, it wouldn't be worth it, it would be a lot of work. As far as parts cost, I would estimate around $2000 for the mount, nose gear strut and main gear weldments. You could reuse the gear legs, just cut them down.

Trigear Sonex show up regularly on the used market, wait for one of them.

In reality though, the sonex is a very easy tail wheel plane. I've never heard of one ground looping. And they just look better in the conventional way.

[DCASonex]

I think Mark posted a few days ago looking for a tail wheel engine mount for A Jab-CAMit 3300 and will be converting from a tri-gear that I think was an Aero-Vee so would have that mount available if that is what you are looking for.

David A.

[david.2.wilcox]

Hi Ed,

I have converted a tailwheel Sonex to a nose wheel, N607LT. My main reason for doing so was for ground/taxi visibility. Tailwheel takeoffs and landings were no problem.

The 50 labor hour estimate was a good one. The advice to wait for an existing nose wheel plane to come onto the market was also good.

But if you go ahead with your plan... You can shorten the standard gear struts for the tri-gear mounts. The axles are the same. I am not familiar with Sonex standard mechanical brakes. This would be a good time to get rid of them. You'll need to obtain the main gear spar mount trusses, an engine mount, the nose wheel parts and a tail skid.

The firewall penetration for the nose wheel steering arm (per Sonex plans) would never pass AC20-135 fire proof requirements. I mention that because I know of one person that decided not to build because of that. It doesn't worry me too much, as long as it will stop smoke.

I found that drilling the main strut holes on the bench is much easier than on the aircraft.* There are a group of holes for flat head screws that hold the spar gear trusses to the main spar. These screws need to be flush on the inside of the spar box. Normally the holes are prepared by dimpling, which will not be possible with the spar already completed. You will have to countersink the inner spar skin and cap using a right angle drill while reaching inside the box.

This would be a major modification, so depending on the vintage of the airworthiness operating limitations, this would put you back into phase one restricted flight. For that you need to contact the local FSDO to agree on a new restricted flight area unless you are in the same location as the original builder. When I contacted FSDO, I proposed 10 takeoffs and landings as being more appropriate for the landing gear change than the standard 5 hours flight time. The FSDO inspector agreed.

*I have built a Sonerai, but not a Sonex. I resurrected my Sonex from a wind damage incident. It was flipped upside down in a microburst at TUS. I replaced everything north of the center longeron and a repaired a lot more.

I have photos of the bench drilling setup of the gear holes. Below are the airframe logbook entires that I made for the tricycle gear modification:

2013-07-20 TSN 351.6
Converted to tricycle landing gear. Tricycle gear components from N997KK except as noted. Drilled legs on bench setup for .7 degrees toe-in per axle. Added bolt bushings at all eight locations. Mounted gear trusses to aircraft using alignment tool from Sonex plans. Installed main gear trusses onto spar box using AN509-12 flat head screws. Holes countersunk on the inside of the box. Two screw stems ground for roll control stop clearance. Roll control stops shortened 1/8 inch for screw clearance. Dynon ADAHAR relocated to cross beam on second bay behind seat. Dynon OAT sensor moved to turtle deck behind radio antenna. Dynon roll servo remounted to clear left gear truss. Parking brake valve installed on master cylinder. Brake lines rerouted and bled. Removed Arduino trim control box. Installed RAC T2-10A elevator servo. Fabricated and installed Sonex tail skid L03-07 per plans. Installed engine mount Sonex part number P12 from N414SX, zero time. Removed carburetor heat box. Replaced oil separator with Sonex part. Weight and balance data: Left 253, Right 252, Nose 131, Total 636 empty. Nose arm -28.4, Spinner arm -52.4, Main arm 24.7. Calculated empty weight center of gravity 13.8 aft of leading edge. Flight restrictions per Scottsdale FSDO, Copeland: "The Phase I restrictions for your aircraft are acceptable. Aircraft movement is limited to KPAN and KFFZ. Instead of 5 hours, you must make 10 takeoffs and full stop landings to complete the Phase I requirements." Aircraft is under phase one flight restrictions.

2013-07-21 TSN 353.9
I certify that this aircraft has completed ten landings as prescribed above and shows no detrimental characteristics, is controllable throughout the flight envelope, and is safe for operation.
David Wilcox
A&P xxxxxxx

[Jim B]

Ed
I converted my TD to the tricycle arrangement after I flew it for 120 hrs and about 300 landing. It cost me $3000 in parts and about 2.5 months of down time. I was working full time and did it from 1 November through 12 January with all the holiday distractions. So it can be done but like some have said most of my firewall attachments were relocated due to engine mount differences.

I now have another 120 hrs on the plane and like the trigear. Both configurations have their advantages.

Good luck
Jim
Ocala,Fl

[Cess32cw]

Ed,
As David mentioned above, I am going the other direction with my new Aerovee Waiex. I have everything that you will need, we could swap gear legs and I may be able to use your tail wheel assembly depending on how your aircraft is equipped. Shoot me a PM if you are interested.
Mark