Vans RV15

[cherk]

47 minutes ago, Thruster88 said:

Did anyone notice the trailing edge on the new to Van's all flying stabilator, looks bit unusual. A brave move considering the controversy when Cessna departed from their recipe and put one on the C177.

 

Gurney(sp) flap 

[Thruster88]

Thanks Ian, we learn something new every day

https://en.wikipedia.org/wiki/Gurney_flap

[rgmwa]

They said the trailing edge angles were put on to increase stick feedback and won't be on the final version. The front of the stabilator is also removable so they can experiment with different nose sections. The whole thing is a flying testbed for their ideas and still quite a long way from a final design.

[rgmwa]

4 minutes ago, rgmwa said:

They said the trailing edge angles (upper and lower surfaces, so not a Guerney flap) were put on to increase stick feedback and won't be on the final version. The front of the stabilator is also removable so they can experiment with different nose sections. The whole thing is a flying testbed for their ideas and still quite a long way from a final design.

... don't know what happened there. Tried to edit my previous post.

Edited August 5, 2022 by rgmwa

[facthunter]

I don't like the idea of a full flying tail. Too prone to flutter. Nev 

[RFguy]

Nev This was a good writeup about tails , and specifically full flying tails : certainly trouble if the pivot point gets too far back.

 

https://www.kitplanes.com/design-process-all-moving-tails/

 

this is public access but I encourage people to get a digial subscription to Kitplanes. it's cheaper than the avgas you'll use flying for 20 minutes.

 

 

 

[facthunter]

Thanks. the best way to fix it is not have it and trim by the normal front part and have a fall back pitch control by doing that. Pitch is "the" ONE  control you must have. Nev

[Thruster88]

6 hours ago, facthunter said:

I don't like the idea of a full flying tail. Too prone to flutter. Nev 

Flutter is bad news. It is lucky you are still with us Facthunter. 🤔

 

 

 

The stabilator on Piper pa 28,32,34, Beech 23,24, Cessna 177, RV12  and others will most definitely flutter if the Vne is exceeded just like the V tail will come off the fork tailed doctor killer if the Vne is exceeded.  

[facthunter]

It gets worse with play in pivots and linkages too, Even the CT has lost a few tails. No way will I want one with that device on it. Nev

[RFguy]

bet that felt strange. like someone grabbing hold of the back of the plane and shaking it 

[facthunter]

You won't feel trim tabs buzzing..   Nev

[Flightrite]

Flutter is not an issue if you fly responsibly within the design limits. I’ve driven numerous all flying tail planes, I’m still here😂 

[Garfly]

 

 

[Thruster88]

On 05/08/2022 at 5:19 PM, Thruster88 said:

Did anyone notice the trailing edge on the new to Van's all flying stabilator, looks bit unusual. A brave move considering the controversy when Cessna departed from their recipe and put one on the C177.

 

The RV15 now has a conventional horizontal stabilizer and elevator. Would be interesting to know if it was market forces  or aero dynamic forces that prevailed. 

[rgmwa]

If they are pushing on with the RV-15 development I assume that's a sign they are on the road to financial recovery. 

[Blueadventures]

31 minutes ago, Thruster88 said:

The RV15 now has a conventional horizontal stabilizer and elevator. Would be interesting to know if it was market forces  or aero dynamic forces that prevailed. 

My guess would be aero as the trailing edge of the AFHS had drag inducers; probably to hold the AFHS in position rather than move up and down slightly in the airstream immediately behind the trailing edge.  (Just my guess.)