Tell me if I understand the tailwheel thing right.

So from what I can see, the normal tailwheel arrangement on an RV has a couple of spring-buffered steering chains that couple the rudder to the tailwheel. Inside the tailwheel assembly is a spring-loaded plunger that (I assume) normally sits in a vertical groove, but with sufficient sideways force it will pop out of the groove and allow the tailwheel to swivel in a full circle if (for example) the pilot were to use a brake and rudder to swing the tail around. Do I understand that correctly?

I was wondering becuase I've seen references to "full swiveling" tailwheels and "steerable" tailwheels, but I've seen video of more than one "steerable" tailwheel swiveling all the way around.

I just ordered the RV-7 secific parts from Van's last week to build my fuselage as a tailwheel 7 instead of the 7a as originally ordered. Now I'm thinking I should have maybe just ordered some of the parts and gotten one of the better tailwheel forks.

Yep you have it right, as the TAILWHEEL turns the spring loaded square stock, rounded on one end rides on a cam and the cam pushes the stock in and allows wheel to disengage and swivel fully. In to's and ldgs, the wheel is locked with the rudder and is dampened with the springs on the chain, making it steerable.
Some use an aftermarket TAILWHEEL mount for more ground clearance, they also steer a little easier than the factory mount. Some also use a steering link instead of chains and springs. They are called a rocket steering link. Hope this helps.

Bird

Yup

Yes, you have it right. Tailwheel is steerable, until the turn radius gets tight enough to slip the "plunger" out of its "slot", and then it freely casters.

Older Van's tailwheels did not have this "full swivel" capability, which limits their turn radius.

What you got from Van's will be full swivel. No need to go aftermarket. The fork that holds the wheel, has a less than ideal geometry (low in front and can catch on ground protrusions), which has caused many of us to switch to something else, but this is an easy switch if you decide you want to later.

+1 for the rocket link

Check the October issue of Kitplanes for pictures.

+1 for both the Rocket Link and the aftermarket tailwheel forks.

My RV-6 was built with the rocket link, and just 2 weeks ago replaced the stock tailwheel fork with a Screaming Eagle fork. The new fork really does require less pedal pressure to steer, and the added ground clearance is very helpful for those times when I inadvertently run my tailwheel off the edge of our runup pad next to the runway and into the grass where there's a bit of a ridge between the pavement and the grass. I should've done this upgrade a year ago when I first bought the plane. Also the process of swapping out the forks was a simple bolt-on affair maybe took about 15-20 minutes tops. It took longer to prep and paint the new metal fork than it did to install it.

tailwheel fork

I have one of these...
http://www.vansairforce.net/buildermodifications/tailwheel/Tailwheel_DougBell.htm

Made by Doug Bell Jr. Very happy with the product and service.

Dale, if you want "the rest of the story" then you will also come across tailwheel configurations (on other aircraft) which may be one of the following:

full swivelling / non steering - these don't have the spring loaded pin and swivel independent of the rudder.

lockable - these have a cockpit control that inserts/retracts a rigid pin; the tailwheel is either full swiveling or locked strait

This past weekend I met a pilot with an older RV-4 which had the steerable, non swiveling tailwheel. They were pushing the plane away from the pump and broke the attachment clip to one spring when the side force became too much for the old rusted clip.

humptybump said:

Dale, if you want "the rest of the story" then you will also come across tailwheel configurations (on other aircraft) which may be one of the following:

full swivelling / non steering - these don't have the spring loaded pin and swivel independent of the rudder.

Click to expand...

I read of an RVer (think it was RV-4) on VAF who didn't have a link between rudder and tailwheel. I flew my RV-6 home one day from a breakfast after the link broke at the rod end bearing and found ground handling to be very manageable. Only time I really noticed the lack of linkage was at slow taxi speed when brakes were needed to assist a turn.

My 1993 vintage RV-6 has the steerable/non swiveling tailwheel. I want to get it changed out at some point as it is a pain to push the airplane backwards.

Operationally it works fine though.

I received the parts today and checked out the steering pin/cam arrangement. Slick!! Somebody was thinking. I think I'll build it with the stock fork, since I already have it, but definitely will add the Rocket Link and control arm (or lop off one side of this one). The chains and springs do not thrill me.

I notice the Van's site says their tailwheel fairing "Will not work on Full Swivel Tailwheel Assembly". Anyone know why? Too small?

The vans TAILWHEEL fairing will work with full swivel. I just finished doing mine,
I did use antis plats tailwheel bracket but would work with vans. It came out great, I have some pics on kitlog, hit the link below. I will probably tear it off after the first off taxiway experience but it sure is kool looking.


Bird

DaleB said:

I received the parts today and checked out the steering pin/cam arrangement. Slick!! Somebody was thinking. I think I'll build it with the stock fork, since I already have it, but definitely will add the Rocket Link and control arm (or lop off one side of this one). The chains and springs do not thrill me.

I notice the Van's site says their tailwheel fairing "Will not work on Full Swivel Tailwheel Assembly". Anyone know why? Too small?

Click to expand...

The Van's tailwheel pant will work with our retrofit fork because our fork moves the tire down and forward. This allows the pant to clear the tapered rod tail spring (aka the "stinger") Most other forks have clearance problems when attempting to install a tailwheel pant.

Pat Hatch has some nice installation photos somewhere on the VAF site.

Of course, putting a tailwheel pant on any fork will reduce the ground clearance, but they do look cool.

YMMV!

Sam Buchanan said:

I read of an RVer (think it was RV-4) on VAF who didn't have a link between rudder and tailwheel. I flew my RV-6 home one day from a breakfast after the link broke at the rod end bearing and found ground handling to be very manageable. Only time I really noticed the lack of linkage was at slow taxi speed when brakes were needed to assist a turn.

Click to expand...

Guilty. I hate having to pick up the tw to roll the plane backward (old style tw). Yes if I lose a brake it will be interesting, but there are lots of ground loop incidents where a link broke & both brakes were fine.

Charlie
RV-4, Slobovia Outernational (MS71)

One of my first RV tailwheel adventures was when I flew a good friend's brand new RV-8 to Oshkosh and back home to Texas. At my first fuel stop on the way there, the tailwheel locking pin stuck and the tailwheel went into freewheel steering mode. I tried to fix it once but it stuck again. I flew the remainder of the trip with the tailwheel in free mode and it was no problem even for a new RV tailwheel pilot, even including a landing and takeoff at KOSH under the emotional pressure of that environment. That speaks volumes for how easy it is to steer a non-locking tailwheel RV on the ground. I do certainly prefer for the locking pin to work correctly but if it doesn't it's not really such at big deal at all.