# Formelsammlung ‘Instrument Rating’

```Range (NM) = 1.25 x (√height station + √FL(ft))
FL(ft) = (Range(ft) / 1.25 - √height)^2```
`WCA = Wind Diff Angle x Wind Speed / TAS`
```RMI: RB = QDM(ADF pointer) - MH
negative value + 360```
`Distance to DME = Altitude ft / 6000 (6000ft = 1 NM above DME)`
```Auf NDB zu -> relative bearing = 0°
Von NDB weg -> relative bearing = 180°```
`Slant range = (time (ms) - 50) / 12,36`
`DMEdist ² = (dist_hor) ^ 2 + height ^ 2`
`Wave length = speed of light (300000km/s) / frequency (Hz)`
```Rate of Descent = GS x 5
(every 10kt in GS = 50ft/min)```
```1 : 60 Regel: 60 NM -> 1° = 1NM
100 NM -> 1.5 NM; 5NM in 100 NM = 3°```
`RMI bearing (compass) -> VAR/DEV -> true bearing`
```Max Radar Range
Range = c / (2 x PRF) OR PRF = c / (2 * Range)
c = 3 x 10^8 m/s for m or km
c = 162.000 NM/s for NM```
```GS ILS glide slope out -> LOC (GS out)
```T ISA = 15° - (FL/10) x 2 (-2° p. 1000ft, -0,65° p. 100m)
1hPa -> 27ft at MSL, 36ft at 10.000ft, 50ft at 18000ft, 15m (50ft) at 5500m```
```QFE from QNH, 27ft = 1hPa, QFE smaller QNH above MSL
Temp > ISA -> QNH > QFF (below sea level inverted)
QFE above MSL < QNH```
`Layer thickness = Δ height (ft) + (0,004 x Δ height (ft) x Δ temp (°C)) PA (Altimeter to ISA) +Δ QNH QNHA (Altimeter to QNH) +Δ temp TA (dangerous-Δ, instr. over read) H ->L-> T ->R-> H`
```PA (Altimeter to ISA)
+Δ QNH
QNHA (Altimeter to QNH)
+Δ temp
TA
`H ->L-> T ->R-> H`
```ISA 700hPa = FL100 = -5°C
ISA 500hPa = FL180 = -21°C
ISA 300hPa = FL300 = -45°C```
```1000ft = 0,305km (ROT: /3 -10%)
1000m = 540NM, 1 km = 0.54NM```
`Wind 2000ft alt. Direction (veers) +30° Speed x2`
`t v -> p ^ (density lin. pressure neg. temp)`
```0° /h (= equator)
30°N - 7.5° /h to R (roughly 1/4)
45°N - 11°/10.5° /h to R
60°N - 13°/h to R
30°S - 7.5° /h to L
Max 15°/h at north pole```
```I AS (indicated on airspeed indicator)
Instrument and Position (absence CAS = IAS)
C AS (Pt - Ps)
Compression (>200kt)
E AS
+ Density (fall in temp)
T AS (increases with height)```