Van's Air Force
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Have Question for Dave Anders
- Thread starter Fasteagle
- Start date
RV-4 rudder
Well OK here goes: I?m building an F1 Rocket and plan on using the RV-4 tail section as does the HRII. Obviously the speeds will be greater than the -4 and I have done a front HS spar beef up; I will use .020 skins on the control surfaces; stiffners on HS between ribs; reinforcing plates on elevator attach points; and a doubler plate on the forward VS.
What I?m curious about is counterbalancing the rudder. Harmon says it?s not necessary but I?d like to know the pros/cons associated with that mod. (Also It wouldn?t hurt increasing the height of the rudder for looks.) I know I know I can go with the -8 VS and rudder or the MKIII, but what I have is the -4 and depending on who you talk to, the -8 is not trusted for the higher Rocket speeds and the -4 is already proven to 300 with only the .020 skin mod.
Just curious before I proceed with the VS.
Frank
Well OK here goes: I?m building an F1 Rocket and plan on using the RV-4 tail section as does the HRII. Obviously the speeds will be greater than the -4 and I have done a front HS spar beef up; I will use .020 skins on the control surfaces; stiffners on HS between ribs; reinforcing plates on elevator attach points; and a doubler plate on the forward VS.
What I?m curious about is counterbalancing the rudder. Harmon says it?s not necessary but I?d like to know the pros/cons associated with that mod. (Also It wouldn?t hurt increasing the height of the rudder for looks.) I know I know I can go with the -8 VS and rudder or the MKIII, but what I have is the -4 and depending on who you talk to, the -8 is not trusted for the higher Rocket speeds and the -4 is already proven to 300 with only the .020 skin mod.
Just curious before I proceed with the VS.
Frank
Toobuilder
Well Known Member
There is a Reno proven Super Six that switched from the std tail to the RV-8 with good flight test data before and after. IIRC, the bigger -8 tail cost some speed on the straights. You might reach out to Bob Mills via PM and see if he's willing to talk about it.
Mike S
Senior Curmudgeon
CHECK WITH THESE GUYS
Check with Eric Hansen at Team Rocket Aerobatics. https://youtu.be/bC5HoMcxZ9Y
They use the F1 rudder with a couple of enhancements as they spend a lot of time close to VNE.
They put a 3rd row of rivets in the top where the CW horn rivets to the rudder top, also a diagonal stiffener in the top 4 inches of the rudder to horn.
And finally some motivational music : https://youtu.be/8dR2zUf_zQw
Check with Eric Hansen at Team Rocket Aerobatics. https://youtu.be/bC5HoMcxZ9Y
They use the F1 rudder with a couple of enhancements as they spend a lot of time close to VNE.
They put a 3rd row of rivets in the top where the CW horn rivets to the rudder top, also a diagonal stiffener in the top 4 inches of the rudder to horn.
And finally some motivational music : https://youtu.be/8dR2zUf_zQw
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Rudder
Additionally, there are no F1 ?kits? anymore. Components are sold to allow a builder to construct a F1 Rocket, but a fair amount of scrounging on the builders part is in order to acquire all that?s needed. There are different engines, different canopies, different wings, and different tails on Rockets.
Additionally, there are no F1 ?kits? anymore. Components are sold to allow a builder to construct a F1 Rocket, but a fair amount of scrounging on the builders part is in order to acquire all that?s needed. There are different engines, different canopies, different wings, and different tails on Rockets.
smokyray
Well Known Member
Balancing Act...
Frank,
I flew my early model RV4/Harmon parts HR2 for nearly 1000 hours. The empennage on mine was stock RV4 with .020 tail feather skins, standard fuse with tip over canopy, IO540C4B5/Hartzell, nothing special except that it was very light for an HR2 as John Harmon assisted the build and (like me) is weight aware.
That said, in the many arenas of sport aviation/HR2 employment a former F16 driver can tread, structural integrity is one I respect. I never, ever saw a need for a counterbalanced rudder through all the speed regimes the amazing airplane is capable, nor did I ever encounter even the slightest hint of flutter.
However comma, if you are determined to have a counterbalanced rudder, my Eagle driver/RV4 guru bro “Hollywood” fabricated the cleanest, most well engineered counterbalanced RV4 rudder I have seen in nearly 30 years of RV-8ing. It’s not gangly like the 7,8 9, but properly proportioned. I can ask him to share his drawings, pics and even plans he has or you can ask him yourself. His website is www.hotelwhiskeyaviation.com
Tell him Smokey says hey...he might even talk you into purchasing a set of ER tanks, highly recommended.
V/R
Smokey
Hollywood’s RV4 with CB rudder
Frank,
I flew my early model RV4/Harmon parts HR2 for nearly 1000 hours. The empennage on mine was stock RV4 with .020 tail feather skins, standard fuse with tip over canopy, IO540C4B5/Hartzell, nothing special except that it was very light for an HR2 as John Harmon assisted the build and (like me) is weight aware.
That said, in the many arenas of sport aviation/HR2 employment a former F16 driver can tread, structural integrity is one I respect. I never, ever saw a need for a counterbalanced rudder through all the speed regimes the amazing airplane is capable, nor did I ever encounter even the slightest hint of flutter.
However comma, if you are determined to have a counterbalanced rudder, my Eagle driver/RV4 guru bro “Hollywood” fabricated the cleanest, most well engineered counterbalanced RV4 rudder I have seen in nearly 30 years of RV-8ing. It’s not gangly like the 7,8 9, but properly proportioned. I can ask him to share his drawings, pics and even plans he has or you can ask him yourself. His website is www.hotelwhiskeyaviation.com
Tell him Smokey says hey...he might even talk you into purchasing a set of ER tanks, highly recommended.
V/R
Smokey
Hollywood’s RV4 with CB rudder
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