Piper ARCHER III Pilot Operating Handbook page 334

SECTION 9
SUPPLEMENT 20
SECTION 7 - DESCRIPTION AND OPERATION (continued)
A. PFD Systems Description (continued)
Horizontal Situation Indicator (HSI)
Heading Data
Magnetic heading is represented in a boxed digital form at the top of the
compass rose. Heading rate (Rate of Turn Indicator) takes the form of a blue
arcing arrow that begins behind the magnetic heading indicator and moves left
or right accordingly. Graduations are provided on the rate of turn indicator scale
to indicate ½ and full standard rate turns. A heading bug is also provided on the
compass rose.
Navigation Data
Navigation data on the PFD takes several forms. A Course Deviation Indicator
(CDI) is always provided on the HSI and a bearing pointer can be optionally
selected for display on the HSI by the pilot. Controls for selecting the source of
navigation data, selecting the display format of the navigation data, and for
selecting the type of compass rose and moving map to be displayed are along the
left side of the PFD. The active flight plan contained in the GPS Nav/Comm unit
selected as the primary navigation source (Nav) can be optionally selected for
display on the HSI as well as the desired range of the optionally selectable
moving map display. If a localizer or ILS frequency is tuned and captured in the
GPS Nav/Comm selected as the Nav source, a Vertical Deviation Indicator (VDI)
and Horizontal Deviation Indicator (HDI) are automatically displayed on the ADI.
While executing an ILS or localizer only approach, the course deviation indicator
(CDI) and glideslope needles on the PFD, as appropriate, may exhibit a slight
oscillatory motion. The oscillatory motion increases from zero amplitude at
approximately 2500 rpm to approximately ½ dot total amplitude at 2700 rpm. The
GI-106 mechanical VOR Indicator needles exhibit this same behavior, only
to a lesser degree. The pilot should fly the "average" localizer/glideslope needle
position or decrease engine rpm to reduce needle oscillation.
In the event glide slope or localizer signals are lost, the HDI
and/or VDI will be displayed as red X's to indicate loss of
signal. The red X'd indicator will only be removed if the
signal is regained. In this case, the PFD Nav source will set
to GPS, or if the GPS Nav/Comm is retuned, to another
frequency. Appropriate action must be taken by the pilot if
on an approach.
REPORT: VB-1611
9-132, 24 of 30
NOTE
REVISED: JANUARY 9, 2006
PA-28-181, ARCHER III
ISSUED: JULY 12, 1995