Tailwheel Crosswind Landing

Thanks to everyone that has provided some very constructive comments. I
certainly will be talking with my mechanic about looking at the
tailwheel in detail.

As for complaicency, as some suggested, I would say not during this
landing, but maybe a tiny bit on other landings. I was lined up as
straight as I ever have been. It could have been a gust as some said,
or a change in wind direction as I touched down. I definetly need to
make sure the stick is in my gut.

Thanks again,

Tom

john smith wrote in message
.. .
Part of my preflight routine on my Champ is to lift the tail and grab
the tailsprings to assure the bolts are tight. A friend had a broken
leaf spring once from landing at an unimproved strip (a harvested
cornfield).
Tailwheel maintenance is something that must not be overlooked between
annuals.
In addition to the security of the tailwheel spring bolts, you can also
check the condition of the wheel bearings, hub and axle, and pivot, lock
mechanism and bearings. Don't forget to add grease to the fitting every
couple of months.

Is there a document that describes how the tailwheel mechanism on a J-3 is
designed, and how it works? I've done a web search on it and didn't find an
explanation of the "detent".

Are most/all J-3 tailwheels the same design?

I took my first ride in a J-3, 2 weeks ago. I got a feel for the "detent"
during taxi practice. It SEEMED that if you didn't push on the rudder too
far, you stayed within the "detent" but if you pushed too far you popped it
out. I could feel when that happened.

Once it popped it seemed that no amount of pushing on the rudder had effect
- so I was castoring?

I got on the brake right away and got her straightened out, and wobbled the
rudders and it got "back" into detent. But I'd like to know, mechanically
what's happening. If there's a drawing I could look at, that might help.

thanks

On Sun, 28 Nov 2004 02:28:05 -0900, "PJ Hunt"
wrote:

As you're landing, you're reducing power and speed which in turn reduces
each one of the above effects causing you to use less right pedal, or
perhaps even a little left pedal to keep it straight or from going to the
right.

That's very likely the case.

In the most recent instance, the left rudder pedal had been re-rigged
since the last time I'd flown the Cub, or at least since last winter,
and the swage left a fuzz of wire bristles that kept catching on my
winter sneakers, which are high-top Nikes with a Gore-tex lining and
waffle-stomper soles. As a result, I simply couldn't use the left
brake, and I went off the runway into the grass after a three-point
landing. Coming home, I landed on two wheels, you bet!

The first thing I did when I got home was to get out the Leatherman
tool and bevel off the sole of both sneakers at the widest part of the
ball of the foot.

all the best -- Dan Ford
email: (put Cubdriver in subject line)

Warbird's Forum www.warbirdforum.com
Piper Cub Forum www.pipercubforum.com
the blog www.danford.net

On Tue, 30 Nov 2004 02:57:43 GMT, gregg wrote:

Are most/all J-3 tailwheels the same design?

I don't think I've ever flown a Cub (there have been four over the
years) that had an original Piper tailwheel. As Dudley mentioned, many
or most are Scotts.

all the best -- Dan Ford
email: (put Cubdriver in subject line)

Warbird's Forum www.warbirdforum.com
Piper Cub Forum www.pipercubforum.com
the blog www.danford.net

On Tue, 30 Nov 2004 02:57:43 GMT, gregg wrote:

I got on the brake right away and got her straightened out, and wobbled the
rudders and it got "back" into detent. But I'd like to know, mechanically
what's happening. If there's a drawing I could look at, that might help.

So would I!

Indeed, if anyone can point to a drawing, I'll post it on the Piper
Cub Forum www.pipercubforum.com -- copyright permitting


all the best -- Dan Ford
email: (put Cubdriver in subject line)

Warbird's Forum www.warbirdforum.com
Piper Cub Forum www.pipercubforum.com
the blog www.danford.net

Cub Driver wrote:

Indeed, if anyone can point to a drawing, I'll post it on the Piper
Cub Forum www.pipercubforum.com -- copyright permitting

For what it's worth, the Aircraft Spruce & Specialty catalogue has "exploded"
drawings and associated parts lists of Scott, Maule, and Lang tailwheels. My
Maule manuals have a large scale version of the drawing for the SFS-P8A
mechanism.

George Patterson
If a man gets into a fight 3,000 miles away from home, he *had* to have
been looking for it.

What I would really like to know, and don't seem to find anywhere, is
how is a tailwheel like a Scott SUPPOSED to work. In other words, is
the released condition only for performing tight ground manuvers or is
it expected to release or castor in other situations? Does it
release differently when there is weight on the tailwheel than when I
have the tail raised during preflight inspection? Overall, I would say
the functioning of entire tailwheel mechanism is a little bit of a
mystery.

The tailwheel should only castor when on the ground when sufficient
breakout force is exerted. In flight, the wheel detent should engage and
the wheel should move with the rudder. The tailwheel springs center the
tailwheel when the weight is off the wheel.

Thomas Ploch wrote:
What I would really like to know, and don't seem to find anywhere, is
how is a tailwheel like a Scott SUPPOSED to work. In other words, is
the released condition only for performing tight ground manuvers or is
it expected to release or castor in other situations? Does it
release differently when there is weight on the tailwheel than when I
have the tail raised during preflight inspection? Overall, I would say
the functioning of entire tailwheel mechanism is a little bit of a
mystery.

Thomas Ploch wrote:

What I would really like to know, and don't seem to find anywhere, is
how is a tailwheel like a Scott SUPPOSED to work. In other words, is
the released condition only for performing tight ground manuvers or is
it expected to release or castor in other situations? Does it
release differently when there is weight on the tailwheel than when I
have the tail raised during preflight inspection? Overall, I would say
the functioning of entire tailwheel mechanism is a little bit of a
mystery.

The Maule tailwheel has two locking pins between the rudder yoke and the wheel
yoke. The top of the wheel yoke has a cam that rests against these pins. If
enough sideways turning pressure is applied (as is the case when you use
differential brake to make a sharp turn), the cam pushes the pins up and the
wheel yoke castors. Since the cam has to push the back of the aircraft up to
move the pins, the less weight on the tailwheel, the easier it is to make the
wheel castor.

George Patterson
If a man gets into a fight 3,000 miles away from home, he *had* to have
been looking for it.

(Thomas Ploch) wrote in message . com...
What I would really like to know, and don't seem to find anywhere, is
how is a tailwheel like a Scott SUPPOSED to work. In other words, is
the released condition only for performing tight ground manuvers or is
it expected to release or castor in other situations? Does it
release differently when there is weight on the tailwheel than when I
have the tail raised during preflight inspection? Overall, I would say
the functioning of entire tailwheel mechanism is a little bit of a
mystery.

It will caster if it's forced past a certain angle of pivot. An
internal mechanism disengages the steering arm from the wheel fork.
This is designed to occur at a point well past the angle that the
rudder/wheel steering springs will take it at full rudder deflection.
You wouldn't want it to disengage before full rudder travel,
certainly, as you might be trying to stop a bad swing on the runway
using the rudder, and the wheel needs to be engaged.
The wheel should disengage freely enough if you are taxiing and
apply full rudder and some brake. The springs will let the wheel pivot
far enough to let the lock disengage. Weight on the wheel shouldn't
make much difference, except that the steering spring length might
shorten a bit and make disengagement easier when the tail pushes down
on the wheel, flexing the tailspring.

Dan