Navigation

NAVIGATION

From NAM Flying School-Airport, there will be a specific object / landmark that we can use to reach the Main Apron.

The same is when we are in a journey with a/c. For example, we were going to training area, there will be an iconic landmark to guide us.

The process of going from one place to other place is called NAVIGATION.

For visual navigation, one of the most important objects for navigation is a landmark, called CHECKPOINT.

INTEREST

Navigation ability is needed in every flight, since we go to other place and we need to know how to get there and come back again.

Remember, if you can’t navigate properly, it could lead to something called lost position.

NEED

BASICNAVIGATION

TOPIC

Before flight, we always use navigation for everyday activities, example: go to school, work, and market.

In flight, we must apply what we know from our everyday activities. If we want to go to places, we need : DIRECTION CHECKPOINT DISTANCE TIME FUEL ALTITUDE

Navigation is process monitor and controlling A/C from a place to another place.

REVISION

Define Navigation

OBJECTIVE

Basic Navigation Navigator Earth Direction Distance Time Altitude Speed

SCOPE

The Air Pilot’s Manual vol. 3 : Air Navigation

PHAK chap. 15 : Navigation

REFERENCES

SHALL WE CONTINUE?

ANY QUESTION?

NAVIGATOR Navigation is process monitor and controlling A/C

from a place to another place. We must realize, as a pilot are navigator, since

our duty to monitor and control the A/C. As a pilot, to be able to control it correctly, we need to AVIATE. Then, we need to be able to tell where we are going. So the

pilot’s role is to NAVIGATE. Last but not least, we must know that a pilot didn’t work alone.

Along way, there must be a contact with another aerodrome, i.e. Approach, Tower, and Radar. So, we also need to COMMUNICATE.

OBJECTIVE :DEFINE NAVIGATION

NAVIGATOR AVIATE. NAVIGATE. COMMUNICATE.


EARTH Earth’s Shape Oblate spheroid flattened at the pole bulge around the equator


EARTH Cardinal Heading

N : 360 / 000 E : 090 S : 180 W : 270


EARTH The nature of a sphere is such that any point on it is exactly

like any other point. There is neither beginning nor ending as far as differentiation of points is concerned.

We use a system of coordinates to locate positions on the earth by means of imaginary reference lines.

These lines are known as : parallels of latitude meridians of longitude.


EARTH Parallel of Latitude The earth rotates on its north-

south axis, which is terminated by the two poles.

The equatorial plane is constructed at the midpoint of this axis.

The particular parallel of latitude chosen as 30° N, and every point on this parallel is at 30° N.


EARTH Meridian of Longitude Which is the measurement of

this east-west distance. Longitude, unlike latitude, has

no natural starting point for numbering.

Longitude is counted east and west from this meridian through 180°.


EARTH Latitude and Longitude

A circle contain 360° of arc1° of arc =60’ of arc1’ of arc =60” of arc

Example : 41°10’20” N 21°54’03” W 10°56’10” S 122°53’03” E 02°09’29” S 106°08’05” E


EARTH Latitude and Longitude


EARTH Equator : 0º of Latitude Pole

90º of Latitude North 90º of Latitude South


EARTH Prime Meridian International Date Line


EARTH Earth’s Magnetic Field

Generated because of the molten rock in earth’s core keep moving and creating convection flow.

The flow resulted in high amount of electricity inside the earth. That caused a magnetic field around the earth.


EARTH Latitude Longitude


EARTHJAKARTA Latitude6°20’00” S Longitude106°08’00”E


EARTHJEDDAH Latitude 21°54’33” N

Longitude39°17’28” E


EARTHDISTANCE Latitude

21°54’33” 6°20’00” +


28°14’

33”

EARTHDISTANCE Longitude

106°08’00” 39°17’28” -


66°50’

32”

EARTH REVIEW

Calculate Latitude & Longitude difference between 2 point in the earth


X 45º28’01”N 9º10’59”E

Y 22º54’29”S 43º11’47”W

DIRECTION COURSE

Course is the intended horizontal direction of travel. HEADING

Heading is the horizontal direction in which an aircraft is pointed. TRACK

Actual horizontal direction made by the aircraft over the earth. BEARING

Horizontal direction of one terrestrial point from another.


DIRECTION True Direction / Heading The true heading (TH) is the direction in which the

nose of the aircraft points during a flight when measured in degrees clockwise from true north


DIRECTION Magnetic Direction / Heading Since the earth magnetic pole

(north magnetic pole is located close to 71° N latitude, 96° W longitude and is about 1,300 miles) displaced from the geographic or true north pole, there will be slight difference in heading when we travel near the pole.


DIRECTION Variation Variation is the angle

between true north and magnetic north.

Algonic Line Isogonic line Rule : West Best, East Least


DIRECTION Variation Effect of variation to the compass


DIRECTION Deviation Due to magnetic

influences within an aircraft such as electrical circuits, radio, lights, tools, engine, and magnetized metal parts, the compass needle is frequently deflected from its normal reading.


DIRECTION Compass Heading Is a heading which was indicated in compass. To determine compass heading, a correction for

deviation must be made, since deviation caused some disturbance on the magnet we have in the compass.


DIRECTION REVIEW


True Heading

Variation Magnetic Heading

Deviation Compass Heading

235º 239º 1ºW

13ºE 2ºE 061º

354º 9ºW 359º

120º 095º 098º

4ºW

076º

240º

063º

4ºE003º

3ºW25ºE

DISTANCE Great Circle Earth is a

sphere, Imagine it was cut through it core.

It will divide the sphere in perfect half.

The great-circle is the shortest distance between two points on the surface of the earth, measured along the surface of the sphere.


DISTANCE Great Circle Distance The earth have spherical shape. A

sphere have circumference 360º of arc.

1º of arc = 60’ of arc 1’ of arc = 60” of arc A standard unit of distance in

navigation is the Nautical Mile, which is the length of 1 minute of arc of any Great Circle / LATITUDE on Earth.

1 nm = 1,852 m = 6,076 feet


DISTANCE Calculating Great Circle Distance City A located at 6°20’00” S 106°08’00”E City B located at 2°09’29” S 106°08’05”E Calculate the distance between city A & B ! Since the Longitude distance very small, it can be

DISREGARDED. 6°20’00” 2°09’29” -

4°10’31”


Remember : 1’ of arc = 1 nm

250,5 nm

4° = 4 x 60 = 240 nm

10’ = 10 x 1 = 10 nm

31” = 31/60 = 0,5 nm

DISTANCE Great Circle Distance


DISTANCE Rhumb Line Rhumb line is a line

crossing all meridians of longitude at the same angle.

In a map, rhumb line distance will look like this :


DISTANCE Rhumb Line In reality the rhumb line will

make a spiral path on its track. WHY? Because earth is a sphere, there

will be a gradient of latitude and longitude as we moved near the pole.

The gradient will make the angle that intercept the meridian steeper, so it seems like spiraling around the earth.


DISTANCE Calculating Rhumb line distance Here we can count the rhumb line distance :

Δ longitude x cos (mean Latitude) City A located at 16°20’00” S 46°08’00”E City B located at 44°09’29” S 106°08’00”E Δ longitude = 60 x 60 = 3,600 nm Mean Latitude = (16 + 44) /2 = 30 3,600 x cos (30) = 3,600 x 0.86

= 3,117 nm


DISTANCE Difference between

Great Circle and Rhumb Line


TIME In celestial navigation, navigators determine the

aircraft’s position by observing the celestial bodies. The apparent position of these bodies changes with time.

Time is measured by the rotation of the earth and the resulting apparent motions of the celestial bodies.


TIME As Earth rotate, sun appears to move from east to

west. The sun travels at a constant rate, covering 360° of

arc in 24 hours. The mean sun transits the same meridian twice in 24 hours. The following relationships exists between time and arc:

Time Arc360° of arc = 24 hours 15° of arc = 1 hour


TIME Time Zone The world is divided into 24

zones, each zone being 15° of longitude wide.

Since the time is earlier in the zones west of Greenwich, the numbers of these zones are plus.

In the zones east of Greenwich, the numbers are minus because the time is later.


TIME GMT Greenwich Mean Time (GMT) is used

for most celestial computations.

Also labeled as UTC or Z time.


TIME Local Time local mean time (LMT) is

mean solar time measured with reference to the observer’s meridian.

measured from the lower branch of the observers meridian, westward through 360°


TIME Time Conversion Since we can conclude our local time from longitude, we can

also count the conversion of time with this rule :360° of arc = 24 hours 15° of arc = 1 hour1° of arc = 4 minutes 15‘ of arc = 1 minute1‘ of arc = 4 seconds15” of arc = 1 seconds


TIME Time Conversion Example : Pangkal Pinang is located at 2°07’59” N 106°07’01” Calculate the local time according to GMT ! USE LATITUDE !

106°=> hours = 106°: 15° = 7 1/15 hours = 7 hours 4 mins

07’=> minutes = 7’ x 4 (sec) = 28 sec

01”=> second = less than 15” can be disregarded


HAHA! PAY ATTENTION!USE LONGITUDE

4 mins

28 sec

7 hours

TIME Review Time conversion : Calculate the local time of Quito, Ecuador 0º15’00” S /

78º35’33”W

78° => hours = 78°: 15° = 5 3/15 hours = 5 hours 12 mins

35’ => minutes = 35’ x 4 (sec) = 140 sec = 2 mins20 sec

33” => second = 33”/15 x1 (sec) = 2 sec


14 mins

22 sec

5 hours

ALTITUDE ISA A certain condition where the pressure is calculated

at MEAN SEA LEVEL indicated 1,013.25 hPa (or 29.92 In.Hg) with average temperature calculated 15ºC or 59ºF.

How could we manage to measure the exact pressure at MSL?

We use Barometer. Mercury Barometer Aneroid Barometer


ALTITUDE ALTIMETRY – Aneroid Barometer

mechanism The altimeter measures the height

of the airplane above a given pressure level.

Since altimeter is a modification from aneroid barometer, the main component is also the same. It contain sealed aneroid wafers which expand and contract with changes in atmospheric pressure from the static source.


ALTITUDE Types of Altitude Indicated Altitude

the value of altitude that is displayed on the pressure altimeter. True Altitude

The vertical distance of the airplane above sea level. The actual altitude. expressed as feet above mean sea level (MSL).

Absolute AltitudeThe vertical distance of an airplane above the terrain, or above ground level (AGL).

Pressure Altitude (PA)The height above the standard datum plane (29.92 "Hg and 15 °C) is PA.


ALTITUDE Height (QFE), Altitude (QNH) and FL (QNE) QFE (Q code - Field Elevation ) : Air pressure above an

airfield . If an altimeter was set to QFE, it will indicate HEIGHT above runway level / elevation (AGL)

QNH (Q code – nautical height ): Air pressure above local mean sea level .If an altimeter was set to QNH , it will indicate ALTITUDE above local Mean Sea Level ( AMSL)

QNE (Q code – Nautical Elevation ): Air pressure above mean sea level in ISA condition. If an altimeter was set to QNE , it will indicate ALTITUDE above MSL ISA ( PRESSURE ALTITUDE)


ALTITUDE Rule: High to Low, LOOK OUT BELOW


ALTITUDE Conversion of 29.92 In.Hg to 1013,2 hPa. 1 inch Hg = 1,000 feet 1 hPa = 30 feet 1 inch Hg = 34 hPa From hPa to In.Hg.

1020 hPa =…. In.Hg


Take the 20Times x3 Add

.53Get 60

Get 60

Get 1.13

Get 1.13Add 29.

Result 30.13 Inch Hg

Rule of Thumb, always count nearest to 1000, SO :

ALTITUDE Review From In.Hg. to hPa

29.41Inch Hg =…. hPa


Take the 41Subtract 53 Divide

:3Get 12

Get 12

Get 4

Get 4Minus1000Result 996 hPa

SPEED ISA (International Standard Atmosphere ) A certain condition where the pressure is calculated at

MEAN SEA LEVEL indicated 1,013.25 hPa (or 29.92 In.Hg) with average temperature calculated 15ºC or 59ºF.

Airspeed is the speed of the aircraft in relation to the air mass surrounding that aircraft.

It is necessary to know whether we have sufficient dynamic pressure to create lift, but not enough to cause damage, and velocity is necessary for navigation.


SPEED Pitot-Static System Accurate airspeed measurement is obtained by

means of a pitot-static system. The system consists of:1. A tube mounted parallel to the longitudinal axis of

the aircraft in an area that is free of turbulent air generated by the aircraft

2. A static source that provides still, or undisturbed, air pressure.


SPEED Pitot-Static System The heart of the airspeed indicator is a

diaphragm that is sensitive to pressure changes.

it located inside the indicator case and connected to the ram air source in the pitot tube.

The indicator case is sealed airtight and connected to the static pressure source.

The differential pressure created by the relative effects of the impact and static pressures on the diaphragm causes it to expand or contract.

As the speed of the aircraft increases, the impact pressure increases, causing the diaphragm to expand. Through mechanical linkage, the expansion is displayed as an increase in airspeed.


SPEED Indicated airspeed (IAS) IAS is the uncorrected reading taken from the face of

the indicator. It is the airspeed that the instrument shows on the

dial.


SPEED Basic airspeed (BAS) Basic airspeed (BAS) is the IAS corrected for instrument

error. Each airspeed indicator has its own characteristics that

cause it to differ from any other airspeed indicator. These differences may be caused by slightly different

hairspring tensions, flexibility of the diaphragm, accuracy of the scale markings, or even the effect of temperature.

It is considered negligible or is accounted for in technical order tables and graphs.


SPEED Calibrated Airspeed (CAS) Calibrated airspeed (CAS) is basic airspeed corrected

for pitot-static error or attitude of the aircraft. This can be called position error.

As the flight attitude of the aircraft changes, the pressure at the static inlets changes. This is caused by the airstream striking the inlet at an angle.

Different types and locations of installations cause different errors.

Can also called Rectified Airspeed (RAS)


SPEED Equivalent Airspeed (EAS) Equivalent airspeed is CAS corrected for

compressibility error. Compressibility becomes noticeable when the

airspeed is great enough to create an impact pressure that causes the air molecules to be compressed within the impact chamber of the pitot tube.

Since the speed of piston engine aircraft is slightly far from reaching Mach speed, the EAS can be regarded the same with IAS.


SPEED True Airspeed (TAS) TAS is equivalent airspeed that has been corrected for

pressure altitude (PA) and true air temperature (TAT) this called density error.

How to calculate TAS? RULE OF THUMB : TAS = IAS ( 1+Altitude/1000 ft x 2%)

Effect of TAS with altitude?


TAS = EAS √ρ̥[ /ρ̥

SPEED Ground Speed (GS) The actual speed of the airplane over the ground. It is

true airspeed adjusted for wind. Groundspeed decreases with a headwind, and increases with a tailwind.


SPEED Effect of Altitude with speed (TAS) Calculate TAS !

IAS = 150 knotsAltitude = 10,000 feetTAS = IAS ( 1 + altitude/1,000 x 2%)TAS = 150 ( 1+ 10,000/1,000 x 2/100)

TAS = 150 ( 1 + 0.2) = 150 x 1.2 = 180 knots Using formula :

TAS = 150 x √1.225/0.875

TAS = 150 x 1.18 = 177 knots


TAS = EAS √ρ̥[ /ρ̥

SPEED Review : Rule of thumb calculating TAS Calculate TAS !

IAS = 250 knotsAltitude = 30,000 feet


TAS = IAS ( 1 + altitude/1,000 x 2%)

TAS = 250 ( 1+ 30,000/1,000 x 2/100)

TAS = 250 ( 1 + 0.6) = 250 x 1.6

= 400 knots


KEY POINTS : Navigator Direction Distance Time Altitude Speed

CONCLUSION

ENDANY QUESTION?

Navigation

Education

navigation earth latitude

visual navigation

topicbasic navigation

objectivedefine navigation

air navigation phak

eastwest distance

natural starting point

iconic landmark