Cherokee 180 prop RPM

On Fri, 14 Apr 2006 13:06:55 +0000 (UTC),
wrote:

: landing gear/brake assembly fairing
Allegedly provide big benefit... +5mph or so. We're working on getting a field
approval for our PA-28-180 to use Warrior fairings.

This is true.

I take the fairings and wheel pants off occasionally to clean up the
brake fluid/dust (that gets everywhere) and to check on the status of
the brakes.

If I fly without the wheelpants, I notice a few mph difference, and
the plane floats less on landing.

-Nathan

On Fri, 14 Apr 2006 13:24:11 GMT, Nathan Young
wrote:

On Fri, 14 Apr 2006 13:06:55 +0000 (UTC),
wrote:

: landing gear/brake assembly fairing
Allegedly provide big benefit... +5mph or so. We're working on getting a field
approval for our PA-28-180 to use Warrior fairings.

This is true.

I take the fairings and wheel pants off occasionally to clean up the
brake fluid/dust (that gets everywhere) and to check on the status of
the brakes.

If I fly without the wheelpants, I notice a few mph difference, and
the plane floats less on landing.

A Cherokee that floats?

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

-Nathan

Roger wrote:
: If I fly without the wheelpants, I notice a few mph difference, and
: the plane floats less on landing.

: A Cherokee that floats?

With aftermarket wingtips and VG's on it, a Cherokee actually floats quite a
bit in ground-effect. At least up to the point where it mushes.

-Cory

--

************************************************** ***********************
* Cory Papenfuss, Ph.D., PPSEL-IA *
* Electrical Engineering *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

In article ,
wrote:

Roger wrote:
: If I fly without the wheelpants, I notice a few mph difference, and
: the plane floats less on landing.

: A Cherokee that floats?

With aftermarket wingtips and VG's on it, a Cherokee actually floats quite a
bit in ground-effect. At least up to the point where it mushes.

or was he getting at floating in water?

--
Bob Noel
Looking for a sig the
lawyers will hate

On Sun, 16 Apr 2006 13:59:21 +0000 (UTC),
wrote:

Roger wrote:
: If I fly without the wheelpants, I notice a few mph difference, and
: the plane floats less on landing.

: A Cherokee that floats?

With aftermarket wingtips and VG's on it, a Cherokee actually floats quite a
bit in ground-effect. At least up to the point where it mushes.

I would think that still means the landing is too fast. With STOL
mods that lower the stall speed the landing speed would be adjusted to
meet the new stall speeds.

Float normally means too fast. If the mods change the characteristics
so that float is still there at the corrected speeds I'd have some
concern.

Typically it takes a while to get used to flying the proper speeds
after adding mods that reduce the stall speed and increase lift at low
speed.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

-Cory

Quite true, but then the concept of "floating" is relegated to any
approach speed above stall-speed. How much speed margin is included in the POH
approach speed? Indeed, for a "slam-dunk" short-field approach, one hangs it on the
prop with a minimal speed margin that gust factor allows.

All I was trying to point out is that the (deserved) bad reputation of the
PA-28 gliding like a refrigerator with power-off can be partially mitigated by the VG
installation.

As a representative datapoint, I fly the approach in my PA-28-180 at 80mph IAS
with 2-notches. The book value says 85 mph (minus 2 x 3mph for the flaps) = 79mph.
With that speed, I've got just a second or two of "finesse" to do at the flare before
the energy is gone and it sinks on. At 75 mph it's a flare-drop-chunk one-motion.
Given the VG's and aftermarket wingtips on it, that's pretty much book corrected for
5mph or so.

Prior to the mods, coming in at 80mph with 2-notches had a pretty ugly sink
rate associated with it.

-Cory

: I would think that still means the landing is too fast. With STOL
: mods that lower the stall speed the landing speed would be adjusted to
: meet the new stall speeds.

: Float normally means too fast. If the mods change the characteristics
: so that float is still there at the corrected speeds I'd have some
: concern.

: Typically it takes a while to get used to flying the proper speeds
: after adding mods that reduce the stall speed and increase lift at low
: speed.

: Roger Halstead (K8RI & ARRL life member)
: (N833R, S# CD-2 Worlds oldest Debonair)
: www.rogerhalstead.com
:
: -Cory

--

************************************************** ***********************
* Cory Papenfuss, Ph.D., PPSEL-IA *
* Electrical Engineering *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

On Mon, 17 Apr 2006 15:23:42 +0000 (UTC),
wrote:

snip
All I was trying to point out is that the (deserved) bad reputation of the
PA-28 gliding like a refrigerator with power-off can be partially mitigated by the VG
installation.
snip

Ever driven a 114 Commander? You'd think it was a refrigerator with
the door open...

TC

On 04/17/06 15:11, wrote:
On Mon, 17 Apr 2006 15:23:42 +0000 (UTC),
wrote:

snip
All I was trying to point out is that the (deserved) bad reputation of the
PA-28 gliding like a refrigerator with power-off can be partially mitigated by the VG
installation.
snip

Ever driven a 114 Commander? You'd think it was a refrigerator with
the door open...

so ... the interior light is on? ;-)


TC


--
Mark Hansen, PP-ASEL, Instrument Airplane
Cal Aggie Flying Farmers
Sacramento, CA

On Mon, 17 Apr 2006 15:23:42 +0000 (UTC),
wrote:

Quite true, but then the concept of "floating" is relegated to any
approach speed above stall-speed. How much speed margin is included in the POH

I always heard it used as referencing the plane not touching down when
it should and all finals as opposed to approaches are normally flown
above stall speed. If the final is normally flown at 1.3 Vso and the
most of the speed bled off in the round out as the plane enters ground
effect the touch down should be gentle.

Think of it this way. As you go into the flare the plane should not
start climbing again. The speed should bleed off so as the plane
comes out of the round out pretty much level in ground effect. Then
just above the runway the nose is raised slightly to finish slowing to
the point where the wheels will settle onto the runway.

approach speed? Indeed, for a "slam-dunk" short-field approach, one hangs it on the
prop with a minimal speed margin that gust factor allows.

Even a short field can be done with out a "slam dunk". Cherokees are
very good at a nice touchdown, immediately lower the nose (after the
mains are on), raise those mechanical flaps, get on the brakes and
full up elevator and they will really stop short.


All I was trying to point out is that the (deserved) bad reputation of the
PA-28 gliding like a refrigerator with power-off can be partially mitigated by the VG
installation.


I've heard people joke about the steep glide, but this is the first I
ever heard it referred to as having a bad reputation.
Why would the PA-28 have a bad reputation for its glide ratio with
power off. I put a bit over 300 hours on one and was quite comfortable
with it. Many high performance singles have a faster rate of descent
with a steeper final than the Cherokee.

As a representative datapoint, I fly the approach in my PA-28-180 at 80mph IAS
with 2-notches. The book value says 85 mph (minus 2 x 3mph for the flaps) = 79mph.

That's faster than I land a Deb or Bonanza, but it is as I recall
about what I used to fly final in the 180. OTOH Vso with only me and
half fuel in the Deb is about 55 MPH. and that equates to a final at
71 MPH. Now that is *steep* and requires a fair amount of power.
Engine out is quite a bit faster as at 71 MPH you don't have enough
energy to flare.

With that speed, I've got just a second or two of "finesse" to do at the flare before
the energy is gone and it sinks on. At 75 mph it's a flare-drop-chunk one-motion.
Given the VG's and aftermarket wingtips on it, that's pretty much book corrected for
5mph or so.

Prior to the mods, coming in at 80mph with 2-notches had a pretty ugly sink
rate associated with it.

I never noticed that and I always used full flaps in both the Cherokee
and the Deb.. It's what I was taught, it's what I was used to and it
was just a matter of controlling the airspeed and initiating both the
round out and flare at the right time.

Actually the Deb with power off and full flaps at the proper speed is
very much like landing a Cherokee 180 in the same configuration. With
practice you can make a gentle touchdown and use very little runway.
They have almost identical wing loading. However with the larger
flaps on the Deb I can hit about 2200 FPM rate of descent if in a
hurry. That does require a bit of a slip though.:-))

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com


-Cory

: I would think that still means the landing is too fast. With STOL
: mods that lower the stall speed the landing speed would be adjusted to
: meet the new stall speeds.

: Float normally means too fast. If the mods change the characteristics
: so that float is still there at the corrected speeds I'd have some
: concern.

: Typically it takes a while to get used to flying the proper speeds
: after adding mods that reduce the stall speed and increase lift at low
: speed.

: Roger Halstead (K8RI & ARRL life member)
: (N833R, S# CD-2 Worlds oldest Debonair)
: www.rogerhalstead.com
:
: -Cory