RANS S-19_LS

[LSA_4_Life]

This may be a dumb question- I'm no engineer, but....I notice the wing attachment on the RANS S-19LS consists of only 6 bolts per side
on the forward spar, with very little penetration into the spar carry through channel. -Is this adequate? Why not bring that spar deeper into
the channel like the Vans RV-12 for more tie-in area? Just asking..

[3Dreaming]

There are many different ways to hold a wing in place. A Taylorcraft uses 5 bolts total per side with one holding both struts at the bottom. A Ercoupe uses 4 bolts to hold the wing panels on, 2 of them are quite large. Steve Wittman designed racing aircraft in the 1930's that used no bolts. The wing spars had stubs that set in pockets on the fuselage and were held in place by flying wires.

[LSA_4_Life]

That makes sense. Although the S19 doesn't have wing struts, all of the forces acting upon the wing attachment point would be
focussed at the wing roots , where the wings meet the fuse. Deeper penetration would not strengthen that spot on the spar.
It just seems like loading that wing would put a lot of stress on the contact points. Also, this is not RANS' first rodeo. I'm
sure that this arrangement has been tried and true for many many years now. Thanks for the reply!

[3Dreaming]

That makes sense. Although the S19 doesn't have wing struts, all of the forces acting upon the wing attachment point would be
focussed at the wing roots , where the wings meet the fuse. Deeper penetration would not strengthen that spot on the spar.
It just seems like loading that wing would put a lot of stress on the contact points. Also, this is not RANS' first rodeo. I'm
sure that this arrangement has been tried and true for many many years now. Thanks for the reply!

The Ercoupe doesn't have struts either.

[LSA_4_Life]

Im planning on building the S19. Any thoughts on the plane, that I may not have come across yet? I'd appreciate any info/ opinions, etc.
Thanx

[MrMorden]

Some airplanes have the wings held in place by a single bolt per side...I would not sweat it unless there have been wing failures.

[zaitcev]

I suggest asking in RANS Clan forums. They have a bunch of builders of Venterra there.
http://www.ransclan.com/forums/forumdisplay.php?20-S-19

[FastEddieB]

Some airplanes have the wings held in place by a single bolt per side...I would not sweat it unless there have been wing failures.

My strutted Sky Arrow has two bolts per side, and honestly they are not all that large.

One of them:



BTW, I put in those clear plastic "ports" to better see them on preflights.

[3Dreaming]

Or the CT that uses no bolts or struts to attach the wings to the fuselage.

[FastEddieB]

Or the CT that uses no bolts or struts to attach the wings to the fuselage.

I should probably know this, but how DO they attach?

Edited to add:

"12. The wing spars are clamped by two main bolts inside the cockpit, so for ground transportation the wings can be easily detached and/or installed by two persons." (bolded mine)


Source: http://flightdesign.com/index.php?page=faq#_11

[Jack Tyler]

"I'm planning on building the S19. Any thoughts on the plane..."

Be sure to use the Search function here and dig back through prior discussions about building the kit. It has been generally recognized that building a Venterra will take a good deal longer than a comparable kit of similar design and at least equal performance - namely, the Vans RV-12. One suggestion I've heard more than once is to compare the build instructions of these two aircraft. Another 'build' consideration is how well the build process is documented and supported. When I was considering a RV-12, one of my main reasons for picking it (despite the more attractive appearance of the S19 to me) was the amazing Vans Air Force of RV-12 builders. The tightening of every bolt seemed to be discussed and photo'd there. For a first time builder, that can be not just reassuring but help move the build along at a better pace.

[3Dreaming]

Or the CT that uses no bolts or struts to attach the wings to the fuselage.

I should probably know this, but how DO they attach?

Edited to add:

"12. The wing spars are clamped by two main bolts inside the cockpit, so for ground transportation the wings can be easily detached and/or installed by two persons." (bolded mine)


Source: http://flightdesign.com/index.php?page=faq#_11

The 2 bolts or pins that you mention hold the spars together. This is hidden by what people call the spar carry through. In reality these pins and the spars do not touch the fuselage at any point, the simply hold the 2 wing halves together. There are 2 pins on the end of each wing panel that engage the fuselage and they are what transfers the load to the wings.

[MrMorden]

The 2 bolts or pins that you mention hold the spars together. This is hidden by what people call the spar carry through. In reality these pins and the spars do not touch the fuselage at any point, the simply hold the 2 wing halves together. There are 2 pins on the end of each wing panel that engage the fuselage and they are what transfers the load to the wings.

The weight of the fuselage against the wings in flight helps lock the two together as well. My understanding is that the CT is designed such that it would fly normally with the spar pins removed completely, as the spars would hold in shear against each other and lock into place in the fuselage. Do not try this at home, of course...

[3Dreaming]

The 2 bolts or pins that you mention hold the spars together. This is hidden by what people call the spar carry through. In reality these pins and the spars do not touch the fuselage at any point, the simply hold the 2 wing halves together. There are 2 pins on the end of each wing panel that engage the fuselage and they are what transfers the load to the wings.

The weight of the fuselage against the wings in flight helps lock the two together as well. My understanding is that the CT is designed such that it would fly normally with the spar pins removed completely, as the spars would hold in shear against each other and lock into place in the fuselage. Do not try this at home, of course...

Your understanding is incorrect. setting in the shop if you remove the pins without supporting the wing the end of the spar will go right through the top of the fuselage. By the same token under positive flight loads the spars will come through the bottom of the spar box. The spar pins do hold the 2 wing halves together so the 2 pins in the end of each wing stays engaged in the fuselage sides. The only part of the spars that are touching anything are the metal bushings that the main pins go through.

[Wm.Ince]

The 2 bolts or pins that you mention hold the spars together. This is hidden by what people call the spar carry through. In reality these pins and the spars do not touch the fuselage at any point, the simply hold the 2 wing halves together. There are 2 pins on the end of each wing panel that engage the fuselage and they are what transfers the load to the wings.

The weight of the fuselage against the wings in flight helps lock the two together as well. My understanding is that the CT is designed such that it would fly normally with the spar pins removed completely, as the spars would hold in shear against each other and lock into place in the fuselage. Do not try this at home, of course...

Your understanding is incorrect. setting in the shop if you remove the pins without supporting the wing the end of the spar will go right through the top of the fuselage. By the same token under positive flight loads the spars will come through the bottom of the spar box. The spar pins do hold the 2 wing halves together so the 2 pins in the end of each wing stays engaged in the fuselage sides. The only part of the spars that are touching anything are the metal bushings that the main pins go through.

Wish there was a sketch (exploded view) of what you are talking about. Some of us have never seen the airplane with the wings removed. I think it would be interesting and educational.