Piper PA-28-236 DAKOTA, Pilot Operating Handbook

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PIPER AIRCRAFT CORPORATION SECTION 9
PA-28-236, DAKOTA SUPPLEMENT 11
ISSUED: OCTOBER 14, 1986 REPORT: VB-910
9-91
Figure 7-1 (cont)
4. NAV (Navigation) Mode Selector switch - provides automatic 45°
VOR-LOC intercept angle; tracking and crosswind correction. The
autopilot utilizes the HDG bug as the VOR course reference and a
separate VOR indicator instrument for left-right information when
using a DG or the course indicator and left-right needle for reference
inputs when using an HSI type compass/VOR display. The NAV
mode provides automatic gain and rate reductions and bank limiting to
improve tracking performance. NAV mode should normally be used as
an enroute function. Select APR mode for LOC and VOR approaches.
NOTES
The heading bug is disabled when using an HSI
and NAV, APR or REV is selected, except when
using selected angle intercept feature (refer to
Special Modes and Operations).
With a D.G., the heading bug must be set to the
desired radio course when using NAV, APR or
REV modes.
Select desired course on HSI course selector (or OBS and D.G.) and
select NAV mode for VOR tracking.
5. APR (Approach) Mode Selector switch - provides automatic 45°
VOR-LOC intercept angle, tracking and crosswind correction during
instrument approach operations. D.G./ H.S.I. operation and function
are identical to NAV mode. Select the desired course on H.S.I. (or
O.B.S. and D. G.) course selector and select APR mode.
6. REV (Back Course) Mode Selector Switch - for use in tracking the
LOC front course outbound, or the LOC back course inbound, or the
published VOR approach course outbound. When using an HSI display
always set the course selector on the inbound front localizer course
or VOR inbound published approach course when using REV mode.
When using a D.G. the heading bug must be set to the final approach
course.
7. Pitch Modifier 1 Attitude Selector switch
The pitch data modifier is a momentary type switch that is used
to select the ATT mode or modify the aircraft attitude. When the
autopilot is engaged, automatic pitch synchronization is provided to
the attitude existing at engagement. In ATT mode, actuation of