Mooney M20C Questions

On the hydraulic flaps, does the position of the silver pump handle
have any bearing on whether or not the hydraulic pressure leaks out of
the flap, once they are extended? (The POH doesn't say that it does.)

There is some mechanism underneath the instrument panel that has some
adjustment for the Positive Control. What does it do, exactly?

On 18 Apr 2007 08:10:13 -0700, Greg Esres wrote:

On the hydraulic flaps, does the position of the silver pump handle
have any bearing on whether or not the hydraulic pressure leaks out of
the flap, once they are extended? (The POH doesn't say that it does.)


Yes. That's how you retract the flaps.

There is some mechanism underneath the instrument panel that has some
adjustment for the Positive Control. What does it do, exactly?

I don't recall anything at all like that in either the '68C or the '65E
models with which I have experience.
--ron

Yes. That's how you retract the flaps.

No, the retraction mechanism is a little flap-like lever *above* the
silver handle. Lifting it up releases the hydraulic pressure. When
it's down, the pressure should remain.

The silver handle I'm talking about is the pumping handle.

The flaps are coming up some times when I'm not looking and I haven't
established a pattern yet. ;-)



On Apr 18, 7:47 pm, Ron Rosenfeld wrote:
On 18 Apr 2007 08:10:13 -0700, Greg Esres wrote:

On the hydraulic flaps, does the position of the silver pump handle
have any bearing on whether or not the hydraulic pressure leaks out of
the flap, once they are extended? (The POH doesn't say that it does.)

Yes. That's how you retract the flaps.

There is some mechanism underneath the instrument panel that has some
adjustment for the Positive Control. What does it do, exactly?

I don't recall anything at all like that in either the '68C or the '65E
models with which I have experience.
--ron

Although I have relatively little experience in this aircraft, the silver metal pump handle pumps the flaps down when the flap "lever" is in the down position, and the pump handle position didn't matter. (I always unconsciously pulled it back to the top stop whenever I used it however.) The flap "lever" is beside or immediately above the pump handle - I don't remember for sure.

I never saw anything labeled "Positive Control" on the bird I flew.

--
Jim Carter
Rogers, Arkansas
"Greg Esres" wrote in message ups.com...
On the hydraulic flaps, does the position of the silver pump handle
have any bearing on whether or not the hydraulic pressure leaks out of
the flap, once they are extended? (The POH doesn't say that it does.)

There is some mechanism underneath the instrument panel that has some
adjustment for the Positive Control. What does it do, exactly?

the pump handle position didn't matter. (I always unconsciously
pulled it back to the top stop whenever I used it however.)

That's how I read the POH. However, the flaps seem to creep up
sometimes.


I never saw anything labeled "Positive Control" on the bird I
flew.

I thought they all had this? Probably no label....built-in wing
leveler.


Thanks

On 18 Apr 2007 20:27:36 -0700, Greg Esres
wrote:

the pump handle position didn't matter. (I always unconsciously
pulled it back to the top stop whenever I used it however.)

That's how I read the POH. However, the flaps seem to creep up
sometimes.


I never saw anything labeled "Positive Control" on the bird I
flew.

I thought they all had this? Probably no label....built-in wing
leveler.

brushed-aluminum pushbuttojn on left horn of yoke? extra knob on
turn-and-sllip?

Don

On 18 Apr 2007 19:16:58 -0700, Greg Esres wrote:

Yes. That's how you retract the flaps.

No, the retraction mechanism is a little flap-like lever *above* the
silver handle. Lifting it up releases the hydraulic pressure. When
it's down, the pressure should remain.

The silver handle I'm talking about is the pumping handle.

Oh, I misread. It shouldn't make any difference, but I've always left it
fully down (out of the way). On occasion, during pre-flight, it might be in
an intermediate position, though. I'd suspect a leak in the hydraulic
system.


The flaps are coming up some times when I'm not looking and I haven't
established a pattern yet. ;-)



On Apr 18, 7:47 pm, Ron Rosenfeld wrote:
On 18 Apr 2007 08:10:13 -0700, Greg Esres wrote:

On the hydraulic flaps, does the position of the silver pump handle
have any bearing on whether or not the hydraulic pressure leaks out of
the flap, once they are extended? (The POH doesn't say that it does.)

Yes. That's how you retract the flaps.

There is some mechanism underneath the instrument panel that has some
adjustment for the Positive Control. What does it do, exactly?

I don't recall anything at all like that in either the '68C or the '65E
models with which I have experience.
--ron


--ron

Ron Rosenfield wrote:

I'd suspect a leak in the hydraulic system.

That's kinda what I was thinking. Thank you.

Don Tuite wrote:

brushed-aluminum pushbuttojn on left horn of yoke?

Yes

extra knob on turn-and-sllip?

Hmmm, I don't think so. There is such a knob on the yoke itself that
is aileron trim. I don't think the system uses the panel turn & slip;
it has its own internal equivalent of a turn coordinator, according to
the documentation I've seen.

On Apr 18, 8:27 pm, Greg Esres wrote:
the pump handle position didn't matter. (I always unconsciously
pulled it back to the top stop whenever I used it however.)

That's how I read the POH. However, the flaps seem to creep up
sometimes.

I never saw anything labeled "Positive Control" on the bird I
flew.

I thought they all had this? Probably no label....built-in wing
leveler.

Thanks

I'd instruction in a lot of Mooneys but I've not seen any that didn't
have at least the vac wing leveler autopilot. All the way back in the
early days of the C they had the wing leveler, and later offered an
upgrade to the electric Pathfinder system. The PC system had a check
valve as I recall to prevent leaks in the PC system (which most planes
have) from causing vac failures. Up until 1977 Mooneys were certified
with full-time autopilots (maybe the only plane so certified). The
autopilot was designed to be on all the time unless the pilot actively
held down a button to disable it. Turns are made by selecting left/
right on the controller. However, the A/P is easily over powered.

-Robert, CFII