Skidding turns

On Feb 19, 9:42 pm, C J Campbell
wrote:

The plane is not airworthy if this is the condition. I doubt that the
CFIs are aware of it. Even if they were, they might not report it
because they don't want the plane taken off the line for repairs.

A broken rudder bar spring can cause the rudder to jamb in a spin
recovery. After that there is no way to recover from the spin. Pushing
on the rudder harder just jambs it harder.

See here for a related accident report:

http://www.tsb.gc.ca/en/reports/air/...4/a98q0114.asp

That airplane had two problems: A busted spring, which really
wasn't the issue, and badly worn rudder hinges, which allowed the
rudder stops to override the stop bolt heads and lock in a fully-
deflected position. Since they couldn't get the spin rotation stopped,
they couldn't break the stall. The busted spring was just another
symptom of really poor maintenance. The FAA issued an AD on it.

Dan

wrote in message
...
On Feb 19, 11:40 am, wrote:
On Feb 19, 9:33 am, wrote:





Yesterday on a short sight-seeing x-cntry I noticed the following
flight characteristic of a 1975 C150: whenever I turned to the left,
especially with low power setting, the ball indicated a skid with no
bottom rudder at all.

Explanations I've seen usually are illustrating the danger of skidding
a turn onto final, at high AoA, the typical scenario being tightening
a turn to not overshoot the runway. The inside wing and the rudder are
pointing toward the ground. The ball indicates skid. The pilot gives
more back pressure -- that's where you can get into big trouble.

But I noticed a substantial ball deflection indicating skid with
neutral rudder (shallow turn, not anywhere near critical AoA, by the
way).

In a left turn it seemed to me to take a fair bit of top rudder to
keep the ball centered. That seems weird to me. It doesn't happen in
the 152 or 172 I fly so I'm wondering if other people have seen this
in 150s (or other aircraft) or maybe the ball indicator has a problem?

I remember during my checkride in the same aircraft the ball showed
substantial skid on a demo approach the DE was doing after I had
passed the checkride. He saw it too and corrected, but the plane's
behavior seemed to catch him off guard as well.

You have a broken rudder bar spring. Cessna's springs regularly do
that and will have the airplane uncoordinated, requiring constant
rudder force on one pedal to keep things centered. The unbroken spring
is pulling on one pedal.
The other, more remote possibility, is a worn nosewheel
centering cam. The nosewheel is the rudder's centering system while in
flight on a Cessna single, with the sprung steering pushrods acting as
system centers. Cessna rudder systems are frequently found badly
misrigged, too, since too few mechanics refer to the maintenance
manuals while fixing them.

Dan- Hide quoted text -

- Show quoted text -

Hey thanks, I will convey that info in terms of a question to the FBO
and see what they say. I'm sure other pilots have noted this weirdness
as well.

---------------old post ends-----------

Sorry for putting this in the wrong place, there is a post missing on my
server.

Some of these planes had a little ground adjustable trim tab--which was
adjusted by the simple expedient of bending it by hand. It could obviously
be bent out of position by someone's knee or nearly anything else on the
ramp. I don't recall whether all 150s and 152s had the feature, and I only
ever flew one 152 that was obviously out of rig.

Peter

On Feb 19, 8:33*am, wrote:

In a left turn it seemed to me to take a fair bit of top rudder to
keep the ball centered. That seems weird to me. It doesn't happen in
the 152 or 172 I fly so I'm wondering if other people have seen this
in 150s (or other aircraft) or maybe the ball indicator has a problem?

Sure you weren't flying a helicopter?

-Robert

On Feb 19, 12:26*pm, "Robert M. Gary" wrote:
On Feb 19, 8:33*am, wrote:

In a left turn it seemed to me to take a fair bit of top rudder to
keep the ball centered. That seems weird to me. It doesn't happen in
the 152 or 172 I fly so I'm wondering if other people have seen this
in 150s (or other aircraft) or maybe the ball indicator has a problem?

Sure you weren't flying a helicopter?

-Robert

Hah! For my own safety and that of everyone else I hope I'm not
hallucinating *that* bad!