- Draw a
straight line from Bedford KBED to Stamford (SFM) on Sectional Chart with
your Cessna Flight Computer straight edge
- Pick
Checkpoint (FIX) about 8 to 10 miles (make sure you used the Sectional
Chart rule and not Terminal Area/WAC
- Determine
altitude to fly based on
- Obscuration
- Airspace
- VFR
Course Altitude
i.
0-179 deg odd
thousand plus 500
ii.
180 – 360 deg even thousand plus 500
- Winds
– Turbulence, Winds, temp aloft
- Other
airspace you don’t want to fly in (Boston Class Bravo)
- This
is an example to determine altitude based on obscuration
Sectional
Chart Max
Height {Sectional Chart Quadrant}
BED 1600’
LWM 1100’
Exeter 800’
SFM 1300’
- With
the flight computer measure the “True Course” and fill in the Course
router on the Navigation log. In this case its (024 degree)
- Use
your airport facility directory (AF/D) and the Sectional Chart to
determine:
- Airport
Elevation
- Traffic
Pattern Altitude (Elevation + 1000’)
SFM = 1300’
- Airport
Runways (draw it on Airport Diagram section on Nav log)
- The
frequencies of:
i.
ATIS
ii.
Control Tower
iii.
Ground Control
iv.
Common Traffic advisory Frequency CTAF
v.
Unicom
vi.
FSS
vii.
Departure/Arrival
- Use
the / to indicate TOC top of climb
- From
ATIS (fill in BED wind direction, Velocity and Temperature on the Flight
Nav Log
- From
1-800-WB-Brief (Winds aloft, Temperature) fill in Winds direction and
velocity on flight Nav log
- Rule - for every 1000’ climb the temperature
will drop by 2 degrees C
i.
So, if you will
be flying at 3,500’ and your temperature at Hanscom ground is +2 degrees, then the temperatue at 3,500’ will be: (3,500/1000) * 2 = 7 degree drop or (+2 -7=
-5 degrees C)
- From
Skyhawk 172 S Information Manual page 5-19 Cruise performance
- Since
-5 deg C is current temperature at cruising altitude, and standard
temperature is 15deg C, then -5 deg C will be “10degrees below standard
temperature. So you will have to
use the 20 degrees below standard section.
i.
Because you are at 3,500’ you will round it up to
4,000’ this roundup will give you 2400RPM, %BHP=65, KTAS=100, GPH=9.1 (information form pg 5-19 section 5 of
performance)
ii.
Fill in GPH 9. and 110 KTS 1 on Nav log
- From
the fuel and distance to climb at 2550 lbs look at 4000 (pressure
altitude Feet)
i.
Climb = 73KIAS, Rate of climb = 600’/sec, time = 6,
fuel use = 1.5 gals, distance = 8
ii.
Fill in 73KIAS on Climb True Air Speed (TAS) on Nav
logs
1. Fuel
use = 1.5 Gal + Note 1 “add 1.4 gals to start, taxi and take off
allowance.” This will give you 1.5 + 1.4
= 2.9 Gallons. Put 2.9 gal under fuel on the same line on the Nav logs.
- Calculate
the True Course, TC, True Heading, TH, Magnetic Heading MH
- Fill
in TC =024 = Course Route
you have measured directly with your Flight computer on the sectionals
chart.
- From
the Flight Computer
i.
Set wind direction = 230 degrees under “True Index”
ii.
Mark wind speed = 11Kts up from center hole
iii.
Rotate True course = 024 under “True Index”
iv.
Move slide to put wind dot over TAS (True Air speed)
that will give you 4 deg so its left = - 4 degrees
1. Now
you have 024 degrees True Course – 4 degrees wind correction = 020 degrees.
2. Record
020 on True Heading
v.
Look at the isotonic line; you will see 16 deg W and 15
deg W.
1. since
you are closer to 16deg W, fill in all the TH with + 16
2. So W you are adding => 20deg + 16deg = 36 deg
3. On
climbing out, you will have to turn to 36 degrees for your Magnetic Heading
flight to SFM.
4. Record
036 deg on the nav log on MH.
5. Since
deviation is +/- is about the same, record compass heading CH with 036 degrees
also.
- Calculate
TC, TH, MH, CH for Cruse at 3500’
- 024
follow step on compute to calculate the WCA (Wind Correction Angle)
i.
024 deg – 21 deg = 03 deg
ii.
03 + 16 = 019
degrees
iii.
Follow down the chart with
1. 019
for MH and CH.
And -21 for WAC
2. +
16 for VAR
3. 114
for GS (Ground Speed)