PDA

View Full Version : Piper Pilots! Ned Warrior help!


Dave
June 3rd 05, 10:40 PM
Hi All!

OK... Piper Warrior...PA28-151

Considering purchase...

It's is a 1976 Model..

Specs, (published) say stall, dirty ( Full Flaps ) for a 1976
built is 58 knts.

....1977 and later is 44 knts!

WHAT changes were made to bring the stall speed down by 14
knts!

I have looked at both, I cannot (untrained eye) see what is
different..

Owner of the '76 says 52 knts(w/flaps) , 58 knts "clean"
(????)

Tis a huge difference... is this correct? Why? Can the 76 be
modified to get the stall speed lower?

Can any one help here?

What is the story?

Thanks in advance!

Dave

June 4th 05, 12:19 AM
On 3-Jun-2005, Dave > wrote:

> Specs, (published) say stall, dirty ( Full Flaps ) for a 1976
> built is 58 knts.
>
> ...1977 and later is 44 knts!



Both of these numbers sound VERY bogus. According to specs from the Plane &
Pilot website, a 1981 Warrior II has a full-flaps stall speed of 50 kts.
This is in line with the gear down, full-flaps stall speed of 53 kts for my
Arrow IV which has the same wing but is a bit heavier.

44 kts is the stall speed for a C-172 with full flaps, and no PA-28 model
will come close to that.
58 kts is only 3 kts below the maximum "dirty" configuration stall speed
generally allowed by the FAA for certificated single engine airplanes. I
would expect something like an A-36 Bonanza or a Piper Mirage to have a
"dirty" stall speed in this range, certainly not a Warrior.

I'll bet that Warriors of all vintages have pretty much the same flaps-down
stall speed, and 50 kts sounds about right for that speed.

--
-Elliott Drucker

Vaughn
June 4th 05, 01:28 AM
"Dave" > wrote in message
...
> Hi All!
>
> OK... Piper Warrior...PA28-151
>
> Considering purchase...
>
> It's is a 1976 Model..
>
> Specs, (published) say stall, dirty ( Full Flaps ) for a 1976
> built is 58 knts.
>
> ...1977 and later is 44 knts!
>
> WHAT changes were made to bring the stall speed down by 14
> knts!

Are you sure the units are the same? Older birds used MPH.

Vaughn

Bob Noel
June 4th 05, 02:04 AM
In article >,
Dave > wrote:

> It's is a 1976 Model..
>
> Specs, (published) say stall, dirty ( Full Flaps ) for a 1976
> built is 58 knts.
>
> ...1977 and later is 44 knts!

power on stall? or power off stall? Wouldn't the 150hp vs 160hp
make a difference?

--
Bob Noel
no one likes an educated mule

June 7th 05, 04:24 AM
The numbers are correct, according to the POH. The units are off,
though (as pointed out by another post). Its 58 MPH for the 151, and
44 KTS for the 161. The numbers are in line with what I have
experienced with the 161. Don't know what was changed between 151 and
161 though... I know wings were changed at some point in the warrior
line, but I think that was before 1976.

Chuck
June 7th 05, 04:52 AM
>> OK... Piper Warrior...PA28-151
>>
>> Considering purchase...
>>
>> It's is a 1976 Model..
>>
>> Specs, (published) say stall, dirty ( Full Flaps ) for a 1976
>> built is 58 knts.
>>
>> ...1977 and later is 44 knts!
>>
>> WHAT changes were made to bring the stall speed down by 14
>> knts!
>
> Are you sure the units are the same? Older birds used MPH.
>
>Vaughn
>


I'll bet Vaughn is right on this one. My '63 Cherokee 180 POH is all
MPG instead of KPH. I thought that most companies had switched
totally to KPH by about 1970, but I recently checked out in a '76
Arrow and the POH on it was also full of MPG instead of KPH.

Check with that owner to see if he was quoting knots or statute MPH.
Because those numbers do sound high. My Cherokee 180 POH quotes 57 as
the "Stalling Speed (flaps down, MPH). 57MPG is just under 50 KPH --
about 49 knots. That would be a little more reasonable for a Warrior,
which is very similar in design to a Cherokee.

Oh, and remember -- there are things that can be done to modify those
stall speed numbers. Putting on newer design "Horner" style wing tips
and stabilator tips will drop stall speed about three to five MPH.
Vortex generators on the wing top just behind the leading edge can
drop stall another MPH or two. Flap & aileron seals can make a
difference. Fairings on the flap extension actuators help. Wing root
seals/fairings help. Wheel pants are a BIG help. Etc...

From my reading, you can actually get your stall speed down almost
10MPH by putting on every gizmo kit STC'ed for a Warrior. And at the
same time, you'll be adding top end speed to the plane as you smooth
out the airflow. Problem is -- you'll spend a fortune doing it !!!


Chuck

June 7th 05, 01:20 PM
Chuck > wrote:
: I'll bet Vaughn is right on this one. My '63 Cherokee 180 POH is all
: MPG instead of KPH. I thought that most companies had switched
: totally to KPH by about 1970, but I recently checked out in a '76
: Arrow and the POH on it was also full of MPG instead of KPH.

OK... I can't take it anymore. Unless I missed a meeting, the following are
common abbreviations:
MPH: Miles per hour. Generally assumed statute miles
KPH: Kilometers per hour. Generally not used in aviation AFAIK
MPG: Miles per gallon. Generally assumed to be statute miles.
KT: Knots. A.K.A Nautical miles per hour

The confusion of the OP is about units, so being sloppy in the explanation
doesn't help and adds to my confusion (which I didn't even know I had).

: Oh, and remember -- there are things that can be done to modify those
: stall speed numbers. Putting on newer design "Horner" style wing tips
: and stabilator tips will drop stall speed about three to five MPH.
: Vortex generators on the wing top just behind the leading edge can
: drop stall another MPH or two. Flap & aileron seals can make a
: difference. Fairings on the flap extension actuators help. Wing root
: seals/fairings help. Wheel pants are a BIG help. Etc...

: From my reading, you can actually get your stall speed down almost
: 10MPH by putting on every gizmo kit STC'ed for a Warrior. And at the
: same time, you'll be adding top end speed to the plane as you smooth
: out the airflow. Problem is -- you'll spend a fortune doing it !!!

For the record, the Art Mattison VG's on the Hershey-bar Cherokees does a
really good job of reducing the stall speed. My -180 used to be barely flyable at 60
mph IAS will full flaps. With the VG's (and light-medium loaded), it'll *fly* at
60mph no flaps. Hang it on the prop with full flaps and it doesn't stall until 45mph.

The wingtips help reduce the (already bad) sink of the PA-28's at slow
airspeeds, so it helps climb a bit. The wheel pants give a bit of speed.... 2-3mph on
the old style, 3-5 on the new.

-Cory


--

************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

June 7th 05, 08:54 PM
On 6-Jun-2005, Chuck > wrote:

> I'll bet Vaughn is right on this one. My '63 Cherokee 180 POH is all
> MPG instead of KPH. I thought that most companies had switched
> totally to KPH by about 1970, but I recently checked out in a '76
> Arrow and the POH on it was also full of MPG instead of KPH.

I think you mean MPH (miles per hour) and kts (knots), not MPG (miles per
gallon?) and KPH (kilometers per hour).

>
>
> Oh, and remember -- there are things that can be done to modify those
> stall speed numbers. Putting on newer design "Horner" style wing tips
> and stabilator tips will drop stall speed about three to five MPH.
> Vortex generators on the wing top just behind the leading edge can
> drop stall another MPH or two. Flap & aileron seals can make a
> difference. Fairings on the flap extension actuators help. Wing root
> seals/fairings help. Wheel pants are a BIG help. Etc...

In order to lower stall speed for a given weight, all else being equal, you
need to change the wing's lift coefficient at stalling speed. Thus different
wing tips may help lower stall speed a tiny bit. Vortex generators may help
more. Mods that provide drag reduction (fairings, wheel pants, etc.) should
have NO effect on stall speed. Changing the lift coefficient of the horiz.
stab. will likewise have NO effect because it does not stall before the wing
(except in canard designs).
>
> From my reading, you can actually get your stall speed down almost
> 10MPH by putting on every gizmo kit STC'ed for a Warrior. And at the
> same time, you'll be adding top end speed to the plane as you smooth
> out the airflow. Problem is -- you'll spend a fortune doing it !!!

That is, if you believe all the hype from the people trying to sell these
mods.

--
-Elliott Drucker

June 7th 05, 11:15 PM
wrote:
: > From my reading, you can actually get your stall speed down almost
: > 10MPH by putting on every gizmo kit STC'ed for a Warrior. And at the
: > same time, you'll be adding top end speed to the plane as you smooth
: > out the airflow. Problem is -- you'll spend a fortune doing it !!!

: That is, if you believe all the hype from the people trying to sell these
: mods.

Lots of hype, but I can attest to the VG stall speed decrease... did a
before/after on the same day, same loading, same fuel, etc. Wingtips lowered it a
bit, but not as much as the VG's. I think a lot of people may think that it's all
cumulative, which it rarely is. You might get 3 mph for this, 3 mph for that, and 4
mph for both... not 6, etc. The way to make a plane go faster, stall slower, climb
faster, make margaritas, etc is to sell it and buy one that does it. Most mods do
*very* little for the expense they incur, and can only do so much anyway.

-Cory

************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

Google