Random musings

[Mike S]

Sales/finished/flying figures from Vans show the two place side-by-side as the overwhelming seating configuration choice as does the fact that 50% of models currently available are 2 place SBS. (Forget the nose/tail wheel stuff, not part of the discussion.)

As the 6 evolved into the 7, and its variant the 9, Vans utilized virtually the identical fuselage with different flying surfaces to achieve an airframe targeted at a specific mission.

Now there is the 14-----which I, and many others see as an obvious extension of the 6-->7 evolution.

Which leads me to the question of what a 14 fuselage with flying surfaces targeted to the 9 mission would be like???

Thoughts????

Yes, I know I generalized the design evolution stuff a bit, after all this is "random musings" ------just go with it.

[airguy]

If you mean 9 flying surfaces enlarged for the heavier loads of the 14, but still with the 9 altitude and cruise mission in mind, then yes that would be a clear winner. Otherwise your wing loading is going to be high and the handling will be mushy.

[ChiefPilot]

Originally Posted by airguy

If you mean 9 flying surfaces enlarged for the heavier loads of the 14, but still with the 9 altitude and cruise mission in mind, then yes that would be a clear winner. Otherwise your wing loading is going to be high and the handling will be mushy.

I'm not following the logic.

If you take an RV-14, but don't add a larger wing (the stab is already similarly sized) you end up with ... an RV-14? And this is something with high wing loading and mushy handling? Have you actually run the numbers to see what difference such a change in wing span and area might make regarding wing and spanwise loading? The difference is small. Using similar logic, the RV-10 should have pretty mushy handling since it has a higher wing loading yet.

[scrollF4]

I follow Mike's musings. Van took the RV-7, replaced the shorter, more maneuverable, wing with one that has a wider wingspan and shorter cord line (sp chord line?)...giving the RV-9 more docile handling and "gentlemanly" cruise characteristics.

Mike?s wondering if a similar approach would yield a version of the RV-14 that yields the same sort of kinder gentler cross-country 2-seater as the 7-to-9 approach.

Mike, it seems legit to me.

[rvbuilder2002]

Mike,
We basically consider the RV-14(A) to already be what you are describing except for retaining aerobatic capability.

The RV-14 is flown at take-off, climb, and pattern speeds that are very similar to the RV-9 but at weights up to 300 lbs heavier.

The control response and handling is also toned down by approx the same degree that the RV-9 is to the RV-7

[6 Gun]

Lets go a little different and put the 6cly Lycoming on the 14 now your talking !
Bob

[Chkaharyer99]

IIRC the RV-14 has a shortened RV-10 wing? What if the 14 had a little longer wing version of the RV-10 wing, perhaps full size, would it be more like the RV-9 or more like the 10? Musing or myoozing.

[Mike S]

Originally Posted by Chkaharyer99

IIRC the RV-14 has a shortened RV-10 wing? What if the 14 had a little longer wing version of the RV-10 wing, perhaps full size, would it be more like the RV-9 or more like the 10? Musing or myoozing.

As I recall, the wing on the 9 was designed by John Roncz------for low power/high efficiency cruising. As a two seat SBS, the C/G range could be smaller and that could have had an effect on the design to allow getting the most out of the cruise performance.

The 10 wing was designed by Steve Smith------ http://www.vansairforce.com/community/member.php?u=7474 ----here at VAF. One of the design items that the 10 had to deal with that the 9 does not is the wide C/G envelope due to the rear seat loading. I have no idea how that effects the high efficiency cruise performance.

I am envisioning a wing with a higher aspect ratio like the 9 and an airfoil that is targeted at the lower power and higher efficiency cruise----again like the 9. Not necessary just bolt on a 9 wing, but the same end use design goal.

Scott------thanks for the input, as I well know the 10 is a great cross country cruiser, and very efficient up high. Makes sense to use the wing-----at least most of it to get a lot of the perf benefits without having the time/expense of designing and tooling up for an entirely new wing.

[scard]

Interesting talk about wing design. Just last night Tanya said, "We should go back to cruising at higher altitudes." She doesn't really know much about wing design, nor would I claim to know much more, but she intimately knows her airplane. We spent a few years running back and forth to the west coast at 13-15k' in the -9, sucking O2 all the way watching the airplane perform amazingly. This past weekend we did 6-8k' to/from Petit Jean (granted, shorter leg), but it was obvious that our airplane likes higher. Just sayin', the wing makes a huge difference, and you can feel it. I've been in an RV7 and -8 at those altitudes and wondered what was wrong with the airplane.

[ChiefPilot]

Originally Posted by scard

Interesting talk about wing design. Just last night Tanya said, "We should go back to cruising at higher altitudes." She doesn't really know much about wing design, nor would I claim to know much more, but she intimately knows her airplane. We spent a few years running back and forth to the west coast at 13-15k' in the -9, sucking O2 all the way watching the airplane perform amazingly. This past weekend we did 6-8k' to/from Petit Jean (granted, shorter leg), but it was obvious that our airplane likes higher. Just sayin', the wing makes a huge difference, and you can feel it. I've been in an RV7 and -8 at those altitudes and wondered what was wrong with the airplane.

Haven't been in a 9/9A at 15k. My -6A does quite well up there, though - far better than any other normally aspirated piston single I've had to that altitude (Archers, Arrows, Dakotas, etc). The 9/9A may be marginally better, but it's not like the others are slouches either.