My RANS S-21 Outbound Build

[Marty_d]

Looks like a great kit.

[facthunter]

RANS stuff is.  Nev

[rgmwa]

At the rate you’re putting it together when do you think you might finish it? 

[Kyle Communications]

Very different to a savannah kit. Certainly a lot stronger in build. Also a lot more work as holes are not to size. They are match drilled but you have to redrill them to the correct size. Not fussed on the rivets though they are cherry style. I much prefer the Avex style of rivets

[Kyle Communications]

RGMWA. well it helps when you have a second person helping doing the build. Still a lot to do. Another wing yet and the tail feathers..and they are quite big. But there is a stack of work in the fuselage. Even though it has a prewelded metal cabin cage the whole structure in the rest is quite complex and certainly very strong as well. Rudder cabling and controls are more complex as well. 

 

[Kyle Communications]

07/08/23

Proseal bonded Viton fuel tank scupper plate to inside of upper RH wing skin. 

1.3h
 

[Kyle Communications]

08/08/23

Fabricated fuel cap retainer ring. Marked and cut openings in fuel tank. Vacuumed and flushed fuel tank, checked for leaks under low head. Installed fuel sight gauge and tank flange fittings to tanks. 

5.1h
 

[IBob]

Looking great, Mark........and looks to be really gratifying work too....)

[Mike Gearon]

That’s an earlier  kit. I didn’t realise how much extra work required! I expect you have the new parts that stop the tank sliding backward. 
 

I have a question…. Did the Viton seal location end up being exactly concentric to the upper skin cut out?

 

 

 

 

[rodgerc]

9 hours ago, Mike Gearon said:

Did the Viton seal location end up being exactly concentric to the upper skin cut out?

I’ll jump in to answer, as a multiple RANS 141 wing builder, on Mark’s behalf. 

The wing surface geometry dictates that it won’t be perfectly concentric once the tank stand is installed….This is because the forward edge of the tank stand is around 10mm higher than the aft edge.
 

This aspect, combined with the camber (curve) of the upper wing surface (as compared to the flat surface of the filler flange) means that once everything is tightened up, there is a minor amount of stretching of the scupper seal. 

Reference to the pics below….Lower edge of photos are forward. 

 

Scupper is concentric prior to installation of tank stand (and filler flange)

 

Scupper is marginally eccentric due to stretching induced by tank stand.

 

The eccentricity is very minor and will only be observed by the crew of low flying airliners. 

[Mike Gearon]

Okay. The reason I’m asking is….

 

Those fuel tanks have been problematic from the start. Sizes change for whatever reason related to the mould/ material etc.  Rans have had ongoing struggles with the tanks and mods such as the filler insert and the improved fuel cap assembly.
 

Tanks were also moving rearward which prompted the new rear stop kit. 
 

I suggested at one stage I might make a Viton seal after seeing what a mess YouTube builders were demonstrating as they struggled with the Proseal. Nice to see the Viton seal provided.
 

The other consideration is that those tanks were moving rearward and obviously breaking the Proseal loose. The tank currently sits in place with the new rear plate stopping the main problem rear movement and can be used to provide a concentric position fore/ aft. When you look at the lateral arbitrary movement it seems it can be concentric without concern given the 1 or 2mm variation I see in your pics.

 

So, with consideration to the tank being held in place by a rear support and the the glued Viton seal it worries me that the tank can move forward and laterally a small amount fixed solely by the seal. This then begs the question of why the upper skin isn’t redone with the fuel cap ring 6 holes and smaller inner opening. Then it’d just have a Viton seal at upper and lower surfaces.

 

As such I’ve had laser cut aluminium sheet (pic here) to bond beneath the wing skin then proseal the Viton seal underneath. Provides a heap more sealing and security/ fixing of the tank.  Another Viton seal on upper surface and done.

 

I meant to discuss this with Randy at Osh Kosh and forgot. Might pay a visit before returning to Oz in a few weeks. This is one of my first projects on return so timely to discuss.

Edited August 9, 2023 by Mike Gearon

[Kyle Communications]

09/08/23

Installed fuel tank stand and filler flange. Installed fuel tank retention brackets. Modified sight tube fitting penetrations and installed LH wing root rib. LH wing fabrication complete. 

5.2h 

 

[Kyle Communications]

Major step number 1...first wing is now down at the hangar. The Mistress left wing is now keeping Mabel's parts company

[Marty_d]

Now that wheeled wing dolly is a good looking beast.  I'm copying that.

[Kyle Communications]

Rodger made it up when he did his wings had it stored here for about a year. So I got the hand me down 🙂 ...I also got Gregs 2 benches he made for assembling his S-21.... bargain bonaza . makes life much easier

 

[rgmwa]

3 hours ago, Marty_d said:

Now that wheeled wing dolly is a good looking beast.  I'm copying that.

Here you go:

How to Make a Wing Stand

WWW.EAA.ORG

---

Experimental Aircraft Association

 

 

[Kyle Communications]

Second wing underway

15/08/23

Bolted wing truss to RH main spar. Clecoed ribs to main and rear spars. Levelled wing supports. Shimmed and bolted rear spar to wing truss. Clecoed aileron and flap hinge arms, wing tie-down angle, flap bellcrank mount, aileron bellcrank outer rib support and rib aft attach angles in position. 

4.7h

 

[Kyle Communications]

16/08/23

Match drilled, deburred and riveted aileron and flap hinge arms, ribs aft attach angles, aileron and flap bellcrank attach mounts and root rib forward attach angle to ribs of RH wing. 

2.1h

 

[Kyle Communications]

19/08/23

Riveted ribs 2 to 11 to front and rear spars of RH wing. Riveted tie down angle to front spar. Bolted aileron and flap bellcranks to their mounts and rear spar. Attached rod ends to aileron and flap bellcranks. 

1.6h

 

[Litespeed]

Beautiful kit and same for the work.

 

She will fly like the purring mistress you create.

 

Just beware they can be very jealous- never store weapons in reach of mistress.

[facthunter]

What's the Basic weight of the final result? It's built like a tank. Nev

[Kyle Communications]

For the Rotax version practical Empty weights from ones constructed so far are 380 to 410kg the MTOW with a 100hp Rotax is 727kg

The Titans seem to be somewhere around 430 to 460kg with a MTOW of 820kg

[facthunter]

Thanks for that information. 330 Is  a fairly good figure for something like a Fisher Horizon 2 with a Continental 0-200.  Bit light for my liking.  Nev

[Kyle Communications]

27/08/23

Trimmed and deburred stringers to RH upper wing skin. Installed aileron control and Teleflex flap cables to RH wing. Proseal bonded fuel tank scupper seal to upper RH wing skin. 

2.8h

[Marty_d]

Nev is right - it's built like a brick sh*thouse, the thickness of some of those parts is impressive.