S-19 Progress Report - 03/19/09
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New Nose Gear Fork in Flight Test
The new nose gear is in flight test, and so far so good. We have taken the friction setting way down to 6lbs from 24lbs used on the original fork. The objective is to get the prop blast working to steer and use the brakes less. This is working well, and just a note, we are still using the original brake pads at 350 hours.
Flight Test of Wheel Pants Begins
The install of the wheel pants has been completed and flight testing started. So far we can see a nice increase in cruise speed, from 115 to 119 knots. This is unofficial and not at gross. We expected at least 3 knots, and that may be more realistic. There are a few other areas of drag will be offering fairing for:
1.Gear to fuselage fairing
2.Foot step
3.Nose gear strut
The nose gear has not picked any tendency to shimmy with the wheel pant. This is always a concern since the weight and aero effect of the wheel pant may excite a shimmy response.
Landing Gear are Shipping
We received our first batch of correctly made gear legs. These are being shipped either separately (which we would rather send with the next kit!). They turned out very precise and should mount up fast. We have noticed in our assembly of the gear they need shims. There is a gap between the bottom retaining plate and gear. Use brass sheet to shim, if needing a substantial thickness use aluminum sheet stock to fill the gap, then the brass shim against the gear leg itself.
Canopy Notes
Canopy on production plane has been a learning curse, which most builders will get a direct benefit. What we have learned several trick, like shaping the canopy frame to the width of the roll bar, once it is installed. This really establishes the ability to assemble the canopy fast and in good contour. There are a few other tricks that will be published in the revised instructions, and will post them on line. One big improvement we are doing is using the same seal material that goes between the canopy frame and roll bar, to fit under the plexi glass. You will notice the canopy frame will have a low spot against the roll bar. The way we do this at the factory is to place the D seal material on the canopy frame, use a grommet punch to make holes for the countersunk screws, then cut stand off bushings to suite. This way you can get a nice smooth contour between canopy and windshield glass.

 
350 Hours and Climbing
On my recent trip to Bryan Texas the #1 plane went past 350 hour mark. This plane has been under constant inspection and we are finding the rugged construction paying off in the fact there are no issues. Of course only 350, and there should not be any problems, but it is nice to keep pushing open the airframe service expectations. If properly designed a sheet metal plane will last several thousands of hours, we are sure about this plane in the design department and have no reservations about proving the airframe over time.
Gas cap installation
You may have noticed the fuel tank caps are not coming with the cover. The cover was a concept idea tested on the #1 plane that is not working out for anything other than a cosmetic cover. Rain water still fills the scupper, and needs to be soaked up prior to opening the cap. I have found it is less of a trouble than imagined, as you may recall Cessna has this same design on the C-150, and as a kid I had to do the same thing. The ASTM standards require the filler neck to be sealed so in the event of an overfill fuel does not enter the wing cavity. The new scupper comes as close as possible meeting this requirement; provide there is fuel proof caulk around the scupper and filler neck. NOTE: Fuel proof silicon is available from Spruce and Specialty. It is very expensive, $80 for a ____ounce tube. The good news is one tube will do about 10 planes. I suggest buying and sharing a tube among several builders. If you know of something fuel proof and cheaper, let us know. We have tried several supposedly fuel proof compounds.
Tech Point: On N719RS (the #1 plane) the cover is retained by a ¼ turn fastener, which allows fuel to enter the wing cavity in an overfill case. We thought about making a sealed compartment under the ¼ turn, and several other ideas, and in the end went with the simple, easy to install system provided in the kits. Perhaps a builder will solve the problem, or find painted the gas cap to match the color of the wing is sufficient.
 
Progress on the new interior:
The S-3 close out has been finalized and is shipping with the kits. N719RS had a bit deeper close out, which bothered me to a great extent, since it allowed loading the plane a bit more aft CG than I would like. The new close outs are 2.5” less deep. There is still more baggage space than the 100 HP planes should have. I am aware that if you provide the space it will be filled, so it is only a responsible move to provide baggage space we feel is within the planes practical capacity. Low wings are much more sensitive to aft CG loading, so comparing the S-19 to our other planes you have to consider the nature of the beast.
Front and middle panels have been re-vamped and will feature an arm rest, a large pocket, certification display mount, and recessed headset jack. The center panel now has defined exit points for the control sticks, and cover for the rudder cables and fuel line. There will also be a place to mount a fire extinguisher.
Tips on making smoother wings
The CNC accuracy of the parts means you will have outstandingly straight rivet lines, and smooth contours. However there is always that extra touch needed to make the exceptional ever more outstanding. In the case of the S-19 wings we have found a couple of places that need a bit of skillful touch.
One is the transition of the rib to the top rear spar. A small thin brass washer under the last two rivets will make this flow in perfectly.
To keep the nose ribs to not impress the leading edge skin take care not to over bend the leading edge. The bend should be correct out of the box, and it allows a bit of arching helping shape the nose of the airfoil. If bent past this point it will show up as bumps where the nose ribs contact the tops skins at the very front of the ribs.
Bonding and Shaping of the Wing Tips
On the planes we are building at the factory we have set the wing tips to the fore and aft of the opening and allowed the gap at the joggle joint to increase. It does not matter since we then fill this small gap with bondo and end up with a hidden seam, and fitting perfectly into the wing tip.
 
SUMMARY
We expect to be flying the #2 plane to Sun and Fun, this means it will be operational in a 3 to 4 weeks. This also means we have been pushing the other 4 planes towards completion, as we develop the tooling and technique needed to create a smooth running assembly line. Production rate is still to be around 2 per month then 1 per week if demand is strong.
 
Kits are shipping almost daily. We have stepped it up, and despite the recession we have good business. The extent of the project and our insisting on top QC through out has dogged us with delays and shipping kits with backorders, that all will fade into the past. We are determined to become one of the top producers of fine sheet metal planes. The S-19 project has been winning appeal among a very tough to please customer base, the Vans crowd. We set out to be a great metal plane producer, not to topple Vans; I respect his company and know him as a personal friend and an inspiration. What we bring to the market it the RANS touch in both packaging and engineering. It is this unique “flavor” that has carried this company through the past 26 years, and no doubt will carry us to an exciting future.
 
 
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