Transcript CFII Ground School Summary

Instrument Systems Orals/IPC
and Knowledge Test
Randy Schoephoerster
Air Trek North
2013
Agenda
Instrument Systems
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Compass
Heading Indicator/Directional Gyro
Turn Coordinator
Altimeter
Attitude Indicator
Pitot-Static System
CAUTION…………………..
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The sole purpose of this class is to expedite your passing the FAA knowledge
test. With that said, all extra material not directly tested on the FAA
knowledge test is omitted, even though much more information and
knowledge is necessary to fly safely. Consult the FAR/AIM (CFR) and other
FAA Handbooks for further information along with a Flight Instruction course.
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www.sportys/faatest
CFR 61.65 (d)
Instrument Practical Test Requirements
• (d) Aeronautical experience for the instrument-airplane rating. A
person who applies for an instrument-airplane rating must have
logged:
– (1) Fifty hours of cross country flight time as pilot in command, of
which 10 hours must have been in an airplane; and
– (2) Forty hours of actual or simulated instrument time in the areas of
operation listed in paragraph (c) of this section, of which 15 hours must have
been received from an authorized instructor who holds an instrumentairplane rating, and the instrument time includes:
• (i) Three hours of instrument flight training from an authorized instructor in an
airplane that is appropriate to the instrument-airplane rating within 2 calendar
months before the date of the practical test; and
• (ii) Instrument flight training on cross country flight procedures, including one
cross country flight in an airplane with an authorized instructor, that is
performed under instrument flight rules, when a flight plan has been filed with
an air traffic control facility, and that involves—
– (A) A flight of 250 nautical miles along airways or by directed routing from an air
traffic control facility;
– (B) An instrument approach at each airport; and
– (C) Three different kinds of approaches with the use of navigation systems.
Instrument Rating RQT’s
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Private Pilot
Knowledge Test
50hr Cross Country PIC
40hr Actual or Simulated
– 15 hrs w/CFII
• 250NM IFR Flight Instrument
– Aprroach at each Airport
– 3 Different Kinds of Approaches
• 3hrs with CFII in preceding 2 calendar months
Pitot Static System
Airspeed Indicator
• Ram Air enters the Pitot Tube
• Static Pressure enters the Casing of the Airspeed Indicator
• Higher pressure from the Pitot Tube expands the wafer, drives the
gears, and indicates higher airspeed
• Lower pressure from the Pitot Tube contracts the wafer, drives the
gears, and indicates lower airspeed.
• When the pressure on the Pitot Tube equals the Static pressure, the
Airspeed Indicator reads zero
• What happens when the pitot tube and the drain hole freeze?
Altimeter
• 29.92” HG inside the wafer
• Static Pressure enters the case of the Altimeter
• High Static Pressure compresses the wafer and drives
the gears and indicates low altitude
• Low Static pressure allows the wafer to expand, drives
the gears to indicate high altitude
• If the Static port gets clogged, the altitude indicator
freezes
• What happens if the alternate static air is used?
Altimeter
• Altimeter indicates True Altitude at the field elevation if the local altimeter
setting is used in an accurate altimeter
• Atmospheric pressure decreases about 1in Hg for every 1000ft increase in
altitude
– When changing the kollsman window from 30.11” to 29.96”, the altimeter will
decrease 150ft
• With the current altimeter setting, the altimeter should read within 75ft
of actual altitude to be acceptable
• If pressure or temp becomes lower without adjusting the Kollsman
window, your airplane will be lower than the altimeter indicates.
• Pressure altitude is the altitude read on the altimeter when set to 29.92”
(The standard datum plane)
– This is the altitude used about 18,000ft (Class A)
• Pressure altitude and density altitude are the same at standard
temperature
• The local altimeter setting should be used by all pilots in a particular area
primarily to provide for better vertical separation of aircraft.
When Flying from High to Low
Look out Below!!!!
When Flying from High to Low
Look out Below!!!!!
Reading an Altimeter
Reading an Altimeter
VSI
Vertical Speed Indicator
• Trend Instrument due to the leak
• Measures instantaneous static pressure chg compared to the average
static pressure change over last 6-9 seconds.
• As Static Pressure is lower, then wafer contracts, driving the gears, and
indicates positive rate of climb
• As Static Pressure is higher, then wafer expands, driving the gears to
indicate rate of descent
• If the static port becomes clogged, then the pressure inside the wafer and
the pressure inside the instrument tube will be the same and thus, the VSI
indicates 0 climb or descent
• What happens if alternate air is used? Short term? Long term?
• If the VSI shows a descent of 100ft while on the taxiway during run-up,
what can you do?
Blocked Pitot Tube/Static Port Effects
Blocked Static Port Blocked Pitot and
Drain Hole
Blocked Pitot,
open Drain Hole
Airspeed Indicator
Acts as a reverse
Altimeter
Acts as an
Altimeter
Airspeed = Zero
Altimeter
Frozen at altitude
when Static Port
was Blocked
N/A
N/A
VSI
Reads Zero
N/A
N/A
Mode C
Same as Altimeter
N/A
N/A
Alternate Static Air
• Many airplanes have an alternate static air vent in the event the
static port becomes plugged
• Alternate static air is taken from inside the cabin
• Since air is moving rapidly across the fuselage, bernouli’s indicates
that the cabin air pressure will be slightly lower than the outside air
pressure
• Due to bernoulli’s, Altimeter, Mode C and Altimeter will read
slightly high
• When first using alternate static air, the VSI will initially show a
climb (due to lower pressure), but will then indicate properly
• If Alternate Static Air does not work, or if not installed, break the
glass on the VSI
– Direct access to the Static Line
– Not required for IFR flight
Turn Indicator Vs Coordinator
Powered by Electrical System
Turn Indicator
Turn Coordinator
Rate Of Turn
Rate of Turn
Rate of Roll
Rate of Roll
Vacuum System/Gyro Systems
Turn
Coordinator
Gyro Characteristics
• Spin at 20,000+ RPM
– Takes about 5 minutes to spin
up
• Want to stay in the same place
– Resistance to deflection of the
spinning wheel
– Called Rigidity in Space
• A force applied results in a
reaction 90 degrees in the
direction of the rotation
Gyroscopes
• Turn the battery ON (Master) and listen for
unusual noises after the battery is turned on
but before the engine is started
Gyro Errors
• Attitude Indicator (A/I)
– Indicates climb during acceleration
– Indicates descent during deceleration
– In a 180 degree turn, shows climb and roll in opposite direction
• Directional Guidance (D/G)
– Precesses due to friction
– Max 3 degrees per 15 minutes
– Can tumble at
• >60 degree pitch
• >100 degree bank
– Set the DG to the magnetic compass 5 minutes after the engine
has started. Why?
Attitude Indicate Errors
• Acceleration Error
– Indicates a climb
• Deceleration Error
– Indicates a descent
• Skidding Turn Error
– Indicates a turn in the opposite direction upon return
to straight and level
• Steep Turn Error
– Most pronounced at 1800
– Shows a climb and a turn in the opposite direction
Remote Indicating Compass (RIC)
• Slave Mode puts the
RIC to track the
compass.
• Free Gyro Mode
allows you to adjust
the RIC to the
magnetic compass
• A left deflection
means you push the
clockwise button
Remote Indicating Compass
Test Supplement Book
• Depressing the
Clockwise button will
rotate the compass card
to the right to eliminate
left error
• If the heading on the
RIC is to the left of that
desired, press the
counter clockwise
button
Magnetic Compass Errors
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Turns greater than 18 degree bank may cause compass to hang up on edge of card
UNOS Turning Errors
– Undershoot North, Overshoot South
– 30 deg error at North and South
– Zero deg error at East and West
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ANDS Acceleration/Deceleration Errors
– Accelerate North, Decelerate South
– Due to Counter Weight being heavier than magnet
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Body at rest stays at rest
Body in motion stays in motion
Turbulence causes Compass to oscillate
Deviation
– Errors due to systems in the airplane
– Compass Card correction
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Variation
– Difference between True North and Magnetic North
– Isogonic lines on charts minus for East, add for West
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Timed Turns
– 3 degs/second
Dip Errors (Turning)
Compass Acceleration Error
Magnetic Compass
• On the taxi check, the magnetic compass should swing
freely and indicate known headings
• On a South heading, you turn right.
– The compass will indicate a turn to the right but at a faster
rate than is occurring (UNOS) causing you to overshoot.
• On a North heading, you turn right.
– The compass will indicate a turn to the left (UNOS) causing
you to undershoot.
• On a West or East heading, you turn right or left.
– The compass will indicate the correct magnetic heading
Mach Meter
• Shows the ratio of aircraft true airspeed to the
speed of sound
PFD vs MFD
Glass Cockpits Enhance Situational Awareness