VAF Forums

VAF Forums (https://vansairforce.net/community/index.php)
-   RV General Discussion/News (https://vansairforce.net/community/forumdisplay.php?f=2)
-   -   Tell me if I understand the tailwheel thing right. (https://vansairforce.net/community/showthread.php?t=102764)

DaleB 08-05-2013 02:18 PM

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.

bird 08-05-2013 02:46 PM

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

java 08-05-2013 02:50 PM

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.

bkthomps 08-05-2013 02:58 PM

+1 for the rocket link

DanH 08-05-2013 03:13 PM

Check the October issue of Kitplanes for pictures.

Neal@F14 08-05-2013 03:15 PM

+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.

777Dave 08-06-2013 06:19 AM

tailwheel fork
 
I have one of these...
http://www.vansairforce.net/builderm...l_DougBell.htm

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

humptybump 08-06-2013 08:11 AM

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.

Sam Buchanan 08-06-2013 08:17 AM

Quote:

Originally Posted by humptybump (Post 795046)
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.

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.

DougJ 08-06-2013 08:22 AM

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.


All times are GMT -6. The time now is 12:13 PM.