Rockiedog2
Well-Known Member
- Joined
- Dec 11, 2012
- Messages
- 2,652
On a general purpose tailwheel plane(say utility category G limits) when considering the tubing sizes in the aft fuse...can we make a general statement that the abrupt,beating, jarring loads from the tailwheel would be considered to be more than the expected airloads...or the other way around? Yeah, I know...it depends. Like I said a *general* statement. Maybe based on long time engineering experience
And same question on say an S1S Pitts that would be expected to see near double the airloads of the first example and since the plane is so light maybe the tailwheel loads would be expected to be less than the airloads?
Having looked at many typical homebuilt plans the aft longerons are near always 3/4x035 with same size crossmembers and diagonals back to a couple bays forward of the tailwheel and the diagonals reduce to 5/8x035. Whether it's a Pitts or a Baby Ace. I understand the dimensions may overide the expected loads when comparing 2 different purpose planes etc.
I've used the ratio 55:1 in sizing tubes when I wasn't sure what might be best...so 5/8 would max span 55x.625 = 34.4". Dunno where that came from but it seems to work out about right when studying plans and tube sizes. So far none of my stuff has come apart except all those tailwheels up at OSH. That strip would tear up a middlebuster.
Well always thinking about where might reduce some weight by playing around in the edge of the pad a little and thought some of you tech guys might comment on aft fuse loading.
Thanks
Joe
(notice I didn't ask about whether it's advisable to play around in the margins...I already know that answer)
And same question on say an S1S Pitts that would be expected to see near double the airloads of the first example and since the plane is so light maybe the tailwheel loads would be expected to be less than the airloads?
Having looked at many typical homebuilt plans the aft longerons are near always 3/4x035 with same size crossmembers and diagonals back to a couple bays forward of the tailwheel and the diagonals reduce to 5/8x035. Whether it's a Pitts or a Baby Ace. I understand the dimensions may overide the expected loads when comparing 2 different purpose planes etc.
I've used the ratio 55:1 in sizing tubes when I wasn't sure what might be best...so 5/8 would max span 55x.625 = 34.4". Dunno where that came from but it seems to work out about right when studying plans and tube sizes. So far none of my stuff has come apart except all those tailwheels up at OSH. That strip would tear up a middlebuster.
Well always thinking about where might reduce some weight by playing around in the edge of the pad a little and thought some of you tech guys might comment on aft fuse loading.
Thanks
Joe
(notice I didn't ask about whether it's advisable to play around in the margins...I already know that answer)
