Commercial Pilot
Ground School
Stage 2 Module 2
Flight Computer
Weight & Balance
Flight Computer
Reading Chapters 24 7 12
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Finding True Airspeed
Finding Heading and Ground speed
Time en route and fuel calculations
Wind components
Unit conversions
Find True Airspeed
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20 deg. Celsius
4100 Pressure Altitude
96 KIAS
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Answers?
Answer
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104.1 KTS
Find true heading and ground speed
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Wind 180 @ 10
TC 310
TAS 120
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Answers?
Answer
TH = 306.3 deg.
 GS = 126.2 kts
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Calculate endurance
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Fuel 66
4 gal unusable
9.7 GPH @ 8000’
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Answers?
Answer:
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06:23:30
62 gal.
6500 – (700 + 800)
= 5000 to descend.
5000’ @ 500 FPM
= 10 minutes.
107 Kts. GS
+8 WCA
WCA (+8)
+
Variation (+3)
+
Deviation (+2)
= +13
TC 335 + 13 =
348 deg. CH
10 min. @ 8.5
gph = 1.4 gallons
Using descent info, calculate time to descend.
Calculate actual Ground speed and WCA
Use variation, deviation and calculated WCA to find CH
Use fuel burn and time, get fuel used
Actual Winds Aloft
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TC 180
TH 160
GS 120
TAS 140
Start by setting TC under true index
Place dot at -20 WCA with a 20 kt headwind
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TC 180
TH 160
GS 120
TAS 140
Rotate dot to top. Center at 100.
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TC 180
TH 160
GS 120
TAS 140
Answer: Winds 104 deg. At 50 Knots
Off-course Correction
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Dist. Off / Miles Travelled
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Dist. Off / Miles To Go
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Pointer = Degrees to parallel
Pointer = Degrees to intercept
Total correction = Parallel + Intercept
Off course corrections
Off-Course Correction
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Dist Flown
 150 NM
Off Course
 7 NM
Dist Remaining
 200 NM
( 7 * 60 ) \ 150 = 2.8 degrees to parallel
2.8 + 2.1 = 4.9 degrees
( 7 * 60 ) \ 200 = 2.1 degrees to go direct
Conversions
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Find Statute miles
 100 N.M.
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Find deg. Celsius
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45 degrees F
Weight
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Terminology
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Basic Empty weight = Standard empty weight + optional
equipment.
Standard empty weight = Weight of a standard airplane
including unusable fuel, full operating fluids, and full oil.
Licensed empty weight = Basic empty weight - undrainable
oil (Older aircraft)
Gross weight = Basic empty weight + every thing else that
is loaded in the airplane.
Useful load and Payload
weight cont..
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One gallon of AVGAS= 6 lbs.
One gallon of oil = 7.5 lbs.
Maximum weight- the airplane is limited to
create enough lift for only a certain amount of
weight( C-150=1600lbs).
Maximum Ramp Weight
Maximum Landing Weight
Over weight
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If you load the aircraft over its max weight what
can happen?
higher stall speed
 higher takeoff speed and a longer takeoff run.
 Poor to no climb performance
 lower cruising level
 less maneuverability
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cont.
higher fuel consumption, and less range and
endurance
 reduced cruise speed for a given power setting
 higher landing speed and a longer landing distance
 and greater braking requirements when stopping
 Greater stress on structure of AC.
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Balance
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Center of gravity (CG)
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Pivotal point on the airplane where it would balance.
Moment
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The force (turning effect) acting on the pivotal point (Datum)
of the airplane.
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Weight x Arm = unit/units (pound/feet)
Datum
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Reference plane from which all horizontal distances are
measured.
Completing a weight and balance
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Weight x CG = Moment
Changes (deltas)
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Weight shifted x distance shifted = Gross weight X CG change
CG Change = (Weight shifted x distance shifted) / Gross weight
Center of Gravity
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Effects of movement of CG
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Forward CG
 Nose heavy, may not be able to rotate on takeoff or flare
in the landing.
 More stable aircraft but will not perform as good
Aft CG
 Tail heavy, will want to rotate sooner, will stall a lot
quicker and stall characteristics will be quite different.
 More performance but will not be as stable.