Alpha Systems AOA Eagle Manual

Alpha Systems AOA
6180 140th Ave. N.W.
Ramsey, MN 55303
Customer Support
763.506.9990
[e-mail]
The information contained in this manual is for reference only. If any
information contained herein conicts with similar information contained in
the Airplane Flight Manual, the information in the Airplane Flight Manual shall
take precedence.
COPYRIGHT NOTICE
© 2016, Alpha Systems AOA. All rights reserved.

Eagle
PILOT’S GUIDE
P# AOA-9051-EAGLE

Revision History
Manual Eagle Pilot’s Guide
Rev A - March, 2016
Summary New release

Alpha Systems AOA Eagle Pilot’s Guide
Page TC - 1
Table of Contents
Table of Contents
1. INTRODUCTION 1-1
1.1 Background Information: 1-1
1.2 System Description: 1-1
1.3 Restrictions and Limitations: 1-2
2. EAGLE CONTROLS 2-1
2.1 Display Controls 2-1
2.2 Switch Panel Controls: 2-2
2.3 Eagle Display Segments: 2-3
2.5 Stall Set-point Calibration: 2-5
2.6 Flap Calibration Set-points: 2-5
2.7 Setting Calibrated Day / Night Brightness Levels: 2-6
2.8 Adjusting the Audio Volume Level: 2-7
2.10 Select Audio Type: 2-8
2.11 Brightness Adjustment When Active: 2-9
 2.12In-ightCalibrationFlowChart: 2-9
3. OPERATION 3-1
3.1 Practice High AOA Flight Regime: 3-2
Observed Indications: 3-3
As the recovery progresses: 3-4
3.2 Practice Takeoff and Climb Using AOA: 3-7
Establish Segments Illuminated 3-8
Fly Practice Takeoffs for Familiarization 3-9
3.3 Practice Best Glide Speed: 3-11
Establish Segments Illuminated 3-11
3.4 Practice Approaches Using AOA: 3-13
Establish Segments Illuminated 3-14
Fly Practice Approaches for Familiarization 3-15
Useful Techniques when using the Eagle Indicator 3-16
NOTES 3-18
4. APPENDIX 4-1
4.1 Acronyms and Abbreviations: 4-1
TERMS 4-1
DEFINITIONS 4-1

Alpha Systems AOA Eagle Pilot’s Guide
Table of Contents
Page TC - 2
List of Tables
Table 2-1: Eagle Display Control Features 2-1
Table 2-2: Switch Panel Controls 2-2
Table 2-3: Segment Conditions 2-3
Table 3-1: Observed Indications Chart 3-17

Alpha Systems AOA Eagle Pilot’s Guide
Page 1 - 1
Introduction
1. INTRODUCTION
1.1 Background Information:
The Alpha Systems AOA system was primarily designed to improve
operational safety of airplanes by increasing pilot awareness of available
lift during operations at high angles of attack. Additional benets include
identifying aircraft performance based on a xed angle of attack or a constant
CL, such as maximum range and best glide - Stall.
AOA: Angle of Attack is the difference between the airfoils chord line (a line
from the leading edge to the trailing edge of the wing) and the relative wind
(the inverse of the aircraft ight path).
CL: Coefcient of Lift is a relative measure of an airfoil’s lifting capabilities.
CLmax: Coefcient of Lift Maximum is the angle of attack which if exceeded
will cause the airfoil to stall.
CD: Coefcient of Drag is a measure of total drag; induced and parasite
drag.
CL/CD: Coefcient of Lift over Coefcient of Drag is a ratio between lift and
drag.
CL/CD Maximum: is the maximum lift-to-drag ratio at which maximum range
and maximum glide distance will be found for propeller airplanes.
1.2 System Description:
The Alpha Systems AOA “Eagle,” measures pressure at two points from
an AOA probe mounted solidly to the wing in reference to the cord of the
wing that conveys changing differential pressures, via sense lines, to the IF
module. The IF module converts the pressures into an electronic signal that
is transmitted to the Eagle indicator.
The Eagle indicator interprets the signal and turns on the appropriate
segments to convey the AOA or lift information to the pilot. In addition to
the visual display, the IF module also has an I/O connector that allows
connection of the remote audio interface system that provides warning
annunciations in the pilot’s headset.

Alpha Systems AOA Eagle Pilot’s Guide
Introduction
Page 1 - 2
The Alpha Systems AOA system draws a minimal current of approximately ¼
Amp (250mA) of electrical power. For the system to operate correctly, it must
be supplied electrical power within a range of 12 to 28VDC, be calibrated
correctly and the openings on the AOA probe must be kept clear of any
obstructions - mounted securely in clean air ow.
Probe heat is an option and if installed requires approximately 8 Amps of
electrical power at 12 or 28VDC to operate. To extend the life of the probe’s
heating element, it is recommended that the probe heat not be used while on
the ground.
1.3 Restrictions and Limitations:
The Alpha Systems AOA cannot be placed in the cockpit in such a manner as
to interfere with the pilot’s view of primary ight instruments.
The Alpha Systems AOA cannot be placed in the cockpit in such a manner as
to obstruct the pilot’s view or cause distraction.
The Alpha Systems AOA is a stand-alone system and does not replace any
existing, primary instruments, or displays and is not considered essential for
ight.

Alpha Systems AOA Eagle Pilot’s Guide
Page 2 - 1
Eagle Controls
2. EAGLE CONTROLS
2.1 Display Controls
2 1
Use the table below for a description of the functionality of the controls in
Figure 2-1
Table 2-1: Eagle Display Control Features
ITEM CONTROL FUNCTION
1 Brightness Button This button is at the bottom right of
the Eagle display and when pressed
repeatedly, will step through 16 levels
of brightness. When the maximum
brightness level is reached, the brightness
returns to the minimum and steps up each
time the button is pressed again.
2 Auto Brightness
Photocell The photo cell is at the lower left of the AOA display automatically detects the
ambient light and will switch from “day
time” brightness preset to “night time”
brightness presets automatically. The
Brightness push button can override
either preset at any time.
Figure 2-1 DSTR-AOA-9600 (L2.0 Display)_Straight_Lights_On.png Controls

Alpha Systems AOA Eagle Pilot’s Guide
Eagle Controls
Page 2 - 2
2.2 Switch Panel Controls:
ITEM CONTROL FUNCTION
1Rotary Switch Is an 8 position rotary switch that has a
TRIANGLE SHAPED POINTER to indicate
the switch position, NOT THE SCREW
DRIVER SLOT. There are markings on the
case at 0, 2, 4, 6 but can be positioned
in-between to gain access to the odd
numbered modes when directed in the
calibration procedure.
2 CAL Button This button is the recessed blue button
and is marked “CAL”. This button is used
to enter various calibration values (OAA &
Cruise) during the calibration procedures.
3 SEL Button This button is used to enter the calibration
modes when the rotary switch is in the
corresponding mode set position.
4Audio Mute Switch This switch mutes the audio warning when
in the UP position.
5 Audio Mute LED This amber led illuminates when the audio
alarm has been deactivated by the audio
mute switch.
53
4
2
1
Figure 2-2 pos 0.png Controls
Table 2-2: Switch Panel Controls

Alpha Systems AOA Eagle Pilot’s Guide
Page 2 - 3
Eagle Controls
2.3 Eagle Display Segments:
Nine segments on the display are color coded and will transition and
illuminate with additional available lift from Red triangle in a sequence
to the Green bar and once calibrated (in accordance with the Eagle
Operations Manual AOA-9610), to the angle of attack to the specic aircraft.
A correctly calibrated Eagle will provide a linear increase in AOA indication
as the aircraft slows. The nal stall indications MUST be active prior to the
actual aerodynamic stall. Ensure during post-calibration testing that the nal
Eagle alert state is displayed prior to any stall indications.
The entire slow ight range of no lift to Cruise will allow for a possibility of 14
combinations of colored segments in the following order (Table 2-3):
SEGMENT ABBR CONDITIONS
GGreen Bar with no other segments
indicates Cruise set point, (lots of
lift).
YG Green Bar & Yellow Triangle with
no other segments indicates
slowing/moderate AOA.
YT Yellow Triangle with no other
segments indicates pattern entry/
increasing AOA.
Y1 Yellow Triangle & Chevrons with
no other segments indicates
pattern entry/increasing AOA.
Y2 Yellow Chevrons with no other
segments indicates Base leg/
increasing AOA.
YB Yellow Chevrons & Lower Blue
Doughnut indicates Final/slightly
fast.
B1 Lower Blue Doughnut indicates
Final/slightly fast.
Table 2-3: Segment Conditions

Alpha Systems AOA Eagle Pilot’s Guide
Eagle Controls
Page 2 - 4
BD Complete Blue Doughnut with no
other segments indicates Optimum
Alpha Angle (OAA).
B2 Upper Blue Doughnut with no other
segments indicates slightly slow/
below OAA.
BR Upper Blue Doughnut & Red
Chevrons with no other segments
indicates slightly slow/below OAA.
R1 Red Chevrons with no other
segments indicates too slow (level
1).
R2 Red Chevrons & Triangle with no
other segments indicates too slow
(level 2) and system will announce
calibrated stall warning.
RT Red Triangle with no other
segments indicates critical AOA
(level 3) and system will continue to
announce calibrated stall warning.
Note: No segments illuminated = Power off, no pressure to I/F Module or aircraft on
the ground.

Alpha Systems AOA Eagle Pilot’s Guide
Page 2 - 5
Eagle Controls
2.5 Stall Set-point Calibration:
Stall set-points have been added to the clean OAA and Cruise set-point
calibration procedure at rotary switch position 2.
If desired, a clean Stall set-point can be set by pressing the SEL button after
the Cruise set-point has been set, instead of turning the Rotary Switch to
position 0.
The system will announce “Set Stall Set-point.”
To set the Stall set-point, press the CAL button when at the appropriate ight
pattern. The system will save the set-point and announce “Stall Set-point
Complete.”
When done setting the Stall set-point, turn the Rotary Switch to position 0
and press the SEL button. The system will announce “Calibration Off.”
Note: The system has been set up so that the user can set one, two, or all
three Flap OAA Set-points and one, two, or three Flap Stall Set-points. This
can be done by rotating the Rotary Switch to position 0 after the Flap Set-
point has been set and pressing the SEL button. The system will announce
“Calibration Off” after setting the desired set- points.

Alpha Systems AOA Eagle Pilot’s Guide
Eagle Controls
Page 2 - 6
2.7 Setting Calibrated Day / Night Brightness Levels:
Note: There are 16 levels of brightness from a minimum level to a maximum level.
The Eagle is preset at the factory for daytime/nighttime brightness levels. If
the maximum/minimum brightness levels need to be changed in your aircraft,
do the following procedure to preset both the daytime and
nighttime display brightness levels while on the ground.
1. With power OFF, turn the Rotary Switch to position 3.
2. Hold the SEL button down and power the AOA ON.
3. The unit will announce “Set Brightness Levels” and all LED seg
ments will be illuminated.
4. Cover the photocell on the AOA DISPLAY with your thumb and
wait 5 seconds.
With the photocell covered:
5. Press the brightness button repeatedly on the AOA DISPLAY
until at the acceptable low ambient light brightness level.
6. Wait about 5 seconds for the unit to store the calibrated setting
before removing your thumb.
7. Now, apply light directly to the photo diode on the AOA DISPLAY
and wait 5 seconds.
With light on the photocell:
Press the brightness button repeatedly on the AOA DISPLAY until it is at the
acceptable high ambient light brightness level.
You’ll know when at the maximum brightness level because the unit will
announce “Reached Maximum Brightness”, and going passed it will cause
the brightness of the LED segments to return to the minimum level.
8.) Wait about 5 seconds for the unit to store the calibrated setting
before removing the light from the photocell.
9.) Power the system OFF.

Alpha Systems AOA Eagle Pilot’s Guide
Page 2 - 7
Eagle Controls
2.8 Adjusting the Audio Volume Level:
1. With power OFF, turn the Rotary Switch to position 4.
2. Hold the SEL button down and power the unit on.
3. Wait until the unit announces “Set Volume.”
4. Now, press the CAL button repeatedly until the acceptable vol
ume level.
Note: When at the maximum volume level, the unit will announce “Maximum Volume
Reached.” When at the minimum volume level, the unit will announce “Minimum
Volume Reached.”
5. Power the unit OFF.

Alpha Systems AOA Eagle Pilot’s Guide
Eagle Controls
Page 2 - 8
2.10 Select Audio Type:
1. With power OFF, turn the Rotary Switch to position 5.
2. Hold the SEL button down, power the unit on. The unit will an
nounce “Set Audio Choice.”
Currently there are 5 choices of audio:
A 3 beep audio tone when the AOA increases and the yellow chevron and
only half of the blue doughnut are illuminated (audio occurs once) or,
A 2 note, high / low audio tone when the AOA and when the yellow chevron
and only half of the blue doughnut are illuminated (audio occurs once) or,
A 2 note, high / low audio tone when the AOA increases and when the
yellow chevron and only half of the blue doughnut are illuminated (audio
occurs once) and a feminine voice “Too Slow” annunciation when the red
chevrons and triangle are illuminated (repeats 3 times) or,
A feminine voice “Getting Slow” (audio occurs once) when the
yellow chevron and only half of the blue doughnut are illuminated
and a feminine voice “Too Slow” annunciation when the red
chevrons and triangle are illuminated (repeats 3 times).
A doorbell tone occurs at the yellow chevron and rst half of the blue
doughnut. Then a “Slowing” annunciation occurs at the red chevrons and
triangle indication.
3. Press and then release the CAL button.
4. If you want to select the next audio choice, press the CAL button
again.
5. To select the 3rd audio choice, press the CAL button again.
6. To select the 4th audio choice, press the CAL button again.
Repeat until a desired audio choice is found. At that time, turn power OFF to
the system and that selection will be stored to memory.

Alpha Systems AOA Eagle Pilot’s Guide
Page 2 - 9
Eagle Controls
2.11 Brightness Adjustment When Active:
To change brightness when the unit is active, quickly push and release the
Brightness button until the desired brightness level is reached.
There are 16 brightness levels and a photo cell to detect “nighttime” and
“daytime” ambient light levels and automatically switches to the stored level.
2.12In-ightCalibrationFlowChart:
The following ow charts contain an abbreviated version of the inight
calibration procedures. The complete in-ight calibration procedures can be
found in the Eagle Operations Manual, p/n AOA-9610.
It is highly recommended, to make calibration easier and safer, that the pilot
ies the aircraft while a second person follows the calibration
procedure and enters the appropriate set points for the instrument.
CAUTION
At ALL times, the Pilot-in-Command must y the aircraft in a safe
manner at altitude while maneuvering the aircraft in slow ight.
2.13 Calibrating Flap OAA Set-Points:
Once the system has been successfully calibrated in the “CLEAN”
conguration of BOTH OAA and the CRUISE values, and STORING both
values, the software will allow calibration of up to 3 additional OAA ap
calibrations.
TheapOAAcalibrationprocessisidenticaltothecleanconguration,
yoridentifytheweightadjustedstallspeedforeachwing
conguration,Flap1,Flap2,Flap3,multiplyeachtimes1.3.
Go to switch position 7 and press the SEL button to enter ap calibration.
The unit will announce, “Flap Calibration ON, Set Flap 1”.
After entering the ap calibration routine, perform the ight manuevers for
OAA and press the CAL button.
Press the SEL button to enter the next ap set-point.
Go to switch position 0 and press SEL at any point to SAVE & EXIT the
calibration routine.

Alpha Systems AOA Eagle Pilot’s Guide
Eagle Controls
Page 2 - 10
Once a good OAA Set point has
been achieved, the pilot
continues to STEP 2 and MUST
enter into the Cruise Calibration
Mode or repeat the OAA Set
point Operation.
STEP 1 IN-FLIGHT
CALIBRATION OF EAGLE
OPTIMUM ALPHA
ANGLE (OAA) SET-POINT
Turn the Rotary Switch to position 2
(STEP A). Hold the SEL button and turn
power ON (STEP B). The
Blue Doughnut will ash three time
and the unit will announce “Set-Point
Calibration ON” “Set OAA Set-point”.
The system has entered the OAA set-
point calibration mode.
Note: The Blue Doughnut will quickly
ash every 5 to 6 seconds, indicating
that the system is still in OAA
calibration mode.
To set an OAA,
press and release
the CAL button
(STEP C).
Good OAA
Set-point?
BAD
GOOD
SET
AGAIN?
In-Flight calibration requires the pilot to climb
to a safe altitude for slow ight maneuvers.
The pilot will y the aircraft to the condition
of Optimum Alpha Angle (OAA). Aircraft is at
OAA, when:
1. Aircraft is at a safe altitude for slow ight
maneuvers.
2. Minimum controllable ight, lower power
setting (such as a down wind or landing
pattern power setting).
3. Able to hold altitude, 0 Vertical Speed, not
 descending,zerosink(5to10fpm
climb OK if your aircraft loses
 ightcontrolstabilityat0VS).
4. Full aileron, elevator and rudder
control, not in a buffet, pilot to identify
the set point by pitching back slowly to
a pitch no longer able to climb but able
to hold altitude with full control of the
airplane.
Figure 2-3 DSTR-AOA-9600 (L2.0 Display)_Straight_Lights_On.png Controls
Figure 2-4 pos 2.png Controls
STEP A
STEP C
STEP B

Alpha Systems AOA Eagle Pilot’s Guide
Page 2 - 11
Eagle Controls
Figure 2-6 pos 2.png Controls
STEP A STEP B
Turn the Rotary Switch to
position 0, and press the SEL
button. The system is now
calibrated and in its operational
mode.
STEP 2 IN-FLIGHT
CALIBRATION OF EAGLE
CRUISE SET-POINT
Leave the Rotary Switch in position 2
and press the SEL (white) button
(STEP A). The Green Bar LED will
ash and the system will announce,
“Set Cruise Set-point”. The system has
entered Cruise set-point calibration
mode.
Note: The Green Bar will quickly ash
every 5 to 6 seconds, indicating that
the system is still in Cruise
calibration mode.
To set a Cruise
set-point, press and
release the CAL button
(STEP B).
Good Cruise
Set-point?
BAD
GOOD
SET
AGAIN?
Figure 2-5 DSTR-AOA-9600 (L2.0 Display)_Straight_Lights_On.png Controls
The pilot must y the aircraft at a “Cruise”
In-ight condition, straight and level, holding
altitude at Cruise power. This procedure sets
the display to indicate “Cruise” AOA for the
aircraft.

Alpha Systems AOA Eagle Pilot’s Guide
Eagle Controls
Page 2 - 12
(PAGE INTENTIONALLY LEFT BLANK)