Archer Tach Red Arc

A student has an Archer II that has a red arc painted on the glass of
the tach between 2150 and 2350 RPM. The POH makes no mention of a red
arc.

I'm thinking that either the tach came out of an Arrow (which has a
red arc in this range) or some A&P confused the Archer with an Arrow
and painted it on.

Does anyone know of any legitimate reason for an Archer to have a red
arc, other than max RPM?

Our Cherokee 180C has a similar red arc due to the type of prop we have on
it (can't remember type) for vibration issues. We could put a different prop
on and have the red arc removed. $$$$$$$$$$ Ugh.

Perhaps in a tach from a plane that had this prop, or the Archer actually
has it.

"Greg Esres" wrote in message
...
A student has an Archer II that has a red arc painted on the glass of
the tach between 2150 and 2350 RPM. The POH makes no mention of a red
arc.

I'm thinking that either the tach came out of an Arrow (which has a
red arc in this range) or some A&P confused the Archer with an Arrow
and painted it on.

Does anyone know of any legitimate reason for an Archer to have a red
arc, other than max RPM?

Perhaps in a tach from a plane that had this prop, or the Archer
actually has it.

The owner is unaware of any such installation for this airplane, and
there is no supplement in the POH.

What prop do you have?

I can't remember. 2 blades, though. :-)
I found a digital pic of our logbook from 1968 for an engine overhaul that
says it had a Sensenich. Not sure if that's what's still on it or not. A
friend of mine has an '65 or '66 180. He has the red arc, too.

"Greg Esres" wrote in message
...
Perhaps in a tach from a plane that had this prop, or the Archer
actually has it.

The owner is unaware of any such installation for this airplane, and
there is no supplement in the POH.

What prop do you have?

Greg Esres wrote:
Perhaps in a tach from a plane that had this prop, or the Archer
actually has it.

The owner is unaware of any such installation for this airplane, and
there is no supplement in the POH.

What prop do you have?

It's not just the prop. It's the prop/engine combination. The
Cherokee "C" model 180s and earlier had a hollow crankshaft that caused
some harmonic vibrations between 2150 and 2350. The Archer may have
inherited an airspeed indicator from one of those earlier planes.
Beginning with the '68 "D" model, the 180 hp PA28s were equipped with
the Lyc. O-360-A4x engine, which had a solid crankshaft. This removed
the rpm restriction. The Archer in question should not have any rpm
restrictions (except at 2700), if it is equipped with the factory model
engine and prop.

John Galban=====N4BQ (PA28-180)

Our Cherokee 180C has a similar red arc due to the type of prop we have on
it (can't remember type) for vibration issues. We could put a different prop
on and have the red arc removed. $$$$$$$$$$ Ugh. BRBR

The red arc on the Cherokee is from the Sensenich prop on any hollow crankshaft
Lycoming, namely the O360-A3A engines.

The solution, which was around 1967 and up was a switch on the Cherokee 180's
to an O360-A4A, which has a solid crank and is green arc all the way.

It sounds very suspiciously like the tach from a Cherokee was installed in the
Archer.
--
Dr. Nuketopia
Sorry, no e-Mail.
Spam forgeries have resulted in thousands of faked bounces to my address.

does this archer have the standard engine installed?? then I would not think
that there was an RPM limitation.. if there was an STC for a larger or
different engine prop combination, then that may require the red arc area...
and I agree.. this sounds like something from an Arrow with 3 prop blades..
if there is no documentation of the requirement in the aircraft logs.. then
it is an improper marking on the glass face..

BT

"Greg Esres" wrote in message
...
A student has an Archer II that has a red arc painted on the glass of
the tach between 2150 and 2350 RPM. The POH makes no mention of a red
arc.

I'm thinking that either the tach came out of an Arrow (which has a
red arc in this range) or some A&P confused the Archer with an Arrow
and painted it on.

Does anyone know of any legitimate reason for an Archer to have a red
arc, other than max RPM?

On Mon, 17 Jan 2005 19:04:04 -0800, "BTIZ"
wrote:

does this archer have the standard engine installed?? then I would not think
that there was an RPM limitation.. if there was an STC for a larger or
different engine prop combination, then that may require the red arc area...
and I agree.. this sounds like something from an Arrow with 3 prop blades..

I thought you went to the 3-blade to get rid of the red arc, at least
that's what they said in an article on the conversion a few years
back.

OTOH I've never seen a Cherokee or Archer with the RPM range
limitation. Only an Arrow, but are at least two or three of them I've
probably missed:-))


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

Check the FAA Type Certificate Data Sheets for the Pipers.
You will probably find the prop combination liisted with a note
about the tach marking.

If the prop was a result of an STC, it may not be listed. But
I think I've seen new Pipers with tachs like this.

Probably depends on what dampers are on the engine which
would be indicatded by the engine dash number.

Bill Hale A&P

does this archer have the standard engine installed??

I think so.

if there was an STC for a larger or different engine prop
combination, then that may require the red arc area...

I'll have to check the logs.

this sounds like something from an Arrow with 3 prop blades..

I believe that it's the Arrow 2-blade that has the limitation. We
have one with 3 blades that the mechanic says doesn't need the red
arc, but they left it on anyway.

Thanks