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Key notes

022 InstrumentationChapter 6
SensorUse
Aneroid capsuleAltimeter, manifold (absolute near inlet)
BellowsCabin differential, fuel pressure
Bourdon tubeHydraulic pressure
FaultASIAltimeterVSI
Pitot blockedOver climb / under descend
Static blockedOver descend (SOD)Over descend→ zero
Pitot leakUnder-read
ItemValue
Earth rate15.04°/hr × sin(lat)
Transport driftGS ÷ 60 × tan(lat)
Rate-one turn180°/min, bank ≈ TAS÷10+7
Electrical gyro RPM22 000
Air gyro RPM9000–12 000
ItemValue
DRC accuracy±5° (CS-25 standby ±10°)
Unreliable compassHorizontal field ≤6 μT (~70° lat)
RIC max deviation±10°
Slaved precession2–4°/min
Secular variation move~10 nm/yr
AltitudeTolerance
Sea level±30 ft
20 000 ft±50 ft
40 000 ft±100 ft
ArcSpeeds
WhiteVSO – VFE
GreenVS1 – VNO
YellowVNO – VNE
RedVNE
FormulaNote
LSS38.95 × √OAT(K)
Mach tolerance±0.01
CompressibilityAbove ~200 kt or 10 000 ft
SystemAlignmentTypical error
INS~15–20 min~1.5 NM
IRS3–10 min≤0.5 NM
Schuler period84.4 min
Polar alignment limit70° N/S
ItemValue
Frequency4200–4400 MHz (carrier ~4300)
Range2500 ft
Precision (0–500 ft)±20 ft
Sweep rate~0.01 s
ItemValue
GPWS height0–2500 ft
Warning lead time20–30 s
Caution lead time40–60 s
Stall warning5% CAS or 5 kt
CVR recording30 min
FDR recording25 hours
ItemNote
Cost indexOperating cost ÷ fuel cost
B-RNAV RNP5 NM
P-RNAV RNP1 NM
A/T disengage on ground64 kt
AFCSNo EFIS, no GPS (FMS uses GPS)

Stall → Windshear → GPWS → TCAS

ConstantWhen
Constant IAS climbMach increases
Constant Mach climbIAS decreases
Constant Mach descentIAS increases