Southern Ontario Sonerai 1

[Steve Stephenson]

Rebuilt the tail wheel. It is now a free castoring unit and lighter. Overall, the aircraft also appears to be very *** heavy. CG is damn near 16" in all configurations except empty. I have enough room in the envelope to add a ballast weight at the firewall or forward of that. Trying for 14.25" or as close as possible.

 

[Steve Stephenson]

The totally free castering tail wheel idea was a fail. This was due to the inability to steer with the brakes. They're just too weak for the task. So... I went with a semicastering arrangement. A small length of chain was added to either side so that the chain and springs sag about 1/2 inch. This allows the tail wheel and the rudder to be independent of each other for a few degrees before the springs kick in. The result is fantastic. Tighter turns and great control. Handles alot like a Citabria on the ground.

 

[Steve Stephenson]

The weight and balance got a do-over as well. Correction of some minor errors in previous measurements and calculations plus fresh figures resulted in a C of G that is A-Ok in all configurations.The aircraft is not tail heavy as was previously imagined.

 

[Bil4381]

My S2LS has Cleveland Brakes. When it was test flown the test pilot had the steering rod removed so the tailwheel was free castering.
After he completed hs flights I reinstalled the rod. Later I switched to steering strings connected to the rudder horn. I also made a tailwheel hub using the one from a maule rocket as a pattern. I like it a lot.
Bill E

The totally free castering tail wheel idea was a fail. This was due to the inability to steer with the brakes. They're just too weak for the task. So... I went with a semicastering arrangement. A small length of chain was added to either side so that the chain and springs sag about 1/2 inch. This allows the tail wheel and the rudder to be independent of each other for a few degrees before the springs kick in. The result is fantastic. Tighter turns and great control. Handles alot like a Citabria on the ground.

 

[Steve Stephenson]

Just got back from taking the airplane up for it's first official flight. No drama. The thing hauls ***.

 

[eschrom]

Congratulations, Steve! It's a good feeling, isn't it?

Ed

 

[Steve Stephenson]

Thanks Ed. It sure is. I'll try to take it out again tomorrow.

I'm really glad there's a bunch of people who can relate. This forum is awesome.

 

[Steve Stephenson]

Quick questions for you Ed and other Ed (Raceair) or anyone who knows: 1. Does dropping the rear spar carry thru (trailing edge drop) help stabilize an S1 over 500 lbs? 2. My left wing appears to want to drop and I was wondering how to fix that. 3. My engine has conked out twice on final approach then came back to life. This is inconvenient to say the least since it's not much of a glider. The rest of the circuit is fine. 7 gallons on board on the average. Been a little cool so the carb heat was on. Tried it without - same problem. Any ideas?

 

[eschrom]

Not sure how much help this will be but I'll give it a shot.

1. I understand rear spar dropping to be a go-fast trick, not a stability enhancer, but I could be wrong. In either case, all my experience is with a 2LS, not a 1.
2. It drops in cruise or during a stall? If in cruise, have you adjusted the aileron linkage to droop the left aileron more or the right one less?
3. Ah yes, the VW as pucker generator! Or maybe I should give that credit to the carb. Mine has never stumbled on final but it has during the "go" phase of a touch and go. It's quite an attention getter. I haven't solved it yet but suspect that the slower speed on final raises the air temperature under the cowling and that combined with low fuel causes vaporization. My next attempt might be to point some cooling air directly at the body of the carb. If you come up with something that works I'll very interested to hear about it.

Ed

 

[Steve Stephenson]

I was looking at the rear spar carry through. Left side has one washer. Probably .060. No big deal. The right side has a spacer of roughly 1/4 inch. Given the "wing drop" I'd say the right side actually has a slightly higher angle of incidence. I might try evening the two sides up before fooling with the ailerons. Let me know what you think. The other thing I noticed is my dual port intakes are as hot as hell in July. Maybe during throttle back on final the fuel just evaporates in there. I might use Scat hose to cool them directly. Thanks for responding so quickly.

 

[soneraifred]

Shim the rear spar down on the heavy wing side. All you get when you adjust aileron position is moving the stick center position.

 

[eschrom]

Fred's right about adjusting the ailerons. I shoulda thought it through.

 

[Steve Stephenson]

Thanks guys. I will go with Fred's suggestion. Both wings will have the same angle of incidence when I'm done. Why they don't right now is a mystery but the results speak (or fly) for themselves.

 

[Steve Stephenson]

Here's a pic of how my cooling boxes are. I installed winglets to help direct air toward the combustion part of the cylinder and opened things up for the cylinder heads. The winglets may get reshaped over time (airfoils). So far, cylinder head temps remain between 320 and 350. I'll know more when I push it.

I included it to show where I might sneak in some additional cooling of my intake manifolds/port castings. The outboard part of the cowl opening lines up nicely.

 

[eschrom]

Nice cooling boxes, tidy and attractive. I'm just now finishing a redesign of mine and wish I'd seen yours first. Where do you measure CHT?

 

[Steve Stephenson]

Hi praise coming from you Ed. Between cylinders 1 & 2.

 

[Steve Stephenson]

Unrelated to Sonerai specifically but I had to make a forced landing the other day in my Luscombe. Engine failure on take off. No damage, no injury luckily. Engine sputtered just enough to clear an industrial park that looms at the end of the runway. Looks like the tiny primer line fitting on top of the gascolator came loose. This will now be part of any preflight inspection that I do. Picture is just after touch down and us towing it back to the airport.

 

[Steve Stephenson]

Ignore my previous post about hot intake castings. After doing some research I understand that the intake castings are supposed to be hot. So that's all good. Could be the throttle operator. Lol

 

[Steve Stephenson]

Preliminary measurements indicate the wings are out of alignment with each other by as much as 0.5 degrees. Right wing is greater that the left. Interesting. I will be adding washers to left wing rear spar carry thru attachment "bushing". I thought about taking from the right wing (which has been given roughly 1/4 inch of spacers) and giving to the left. Can someone chime in on this? Will be taking some hyper accurate measurements tomorrow. Am I being too fussy? Let me know.

 

[eschrom]

First get it rigged so that it flies straight and level with neutral aileron, i.e., add washers to the left, then add or subtract the same number of washers from each side to raise or lower the tail in cruise. An airplane that cruises tail low is fighting more drag than it needs to. For example, if you look at my avatar the tail could be raised a bit (but the picture was taken while cruising at Cessna speed so I haven't made any adjustments based on it). I hope this helps.

Ed