NAV Flashcards
(183 cards)
1
Q
02 What is air navigation?
A
The art of directing an aircraft from one position to another, and of determining the position of the aircraft over the earth at any time. (In other words: Finding out where you are, where you should be, and how to match the two)
2
Q
02 What is an oblate spheroid
A
An oblate spheroid is a symmetrical body with a ‘bulge’ in one axis compared to the other (equatorial diameter is longer than the diameter from pole to pole).
3
Q
02 What is a great circle?
A
A circle on the surface of the earth whose centre and radius are those of the sphere itself. A great circle divides a sphere into two equal hemispheres. It is also the shortest distance (along the Earth’s surface) between two points.
4
Q
02 What is the equator?
A
A great circle on the surface of the Earth whose plane is perpendicular to the Earth’s axis of rotation.
5
Q
02 What is a small circle?
A
A circle on the surface of the earth whose centre and radius are NOT those of the sphere itself. All circles on the surface of the Earth that are not great circles are small circles.
6
Q
02 What is a parallel?
A
A small circle on the surface of the Earth whose plane is parallel to the equator.
7
Q
02 What is a Parallel of Latitude
A
Angular distance from the equator measured along a meridian. Units are Degrees° Minutes’ Seconds”. Winnipeg Intl is at 49°54’36”N.
8
Q
02 What is the meridian?
A
A semi-Great circle on the surface of the Earth joining the poles of the Earth.
All meridians converge at the poles.
Meridian is the angular distance from the prime meridian, measured along the shorter arc of the equator.
9
Q
02 What is a rhumb line?
A
A regularly curved line on the surface of the Earth cutting all meridians at the same angle.
A Rhumb line is used to allow a path of flight to be a straight line on some maps. (Eg Mercator projections)
When flying a rhumb line the heading remains constant whereas if flying a great circle constant heading changes are required
10
Q
02 What is a nautical mile (NM)?
A
Length of an arc on the surface of the Earth subtending 1minute. (1/60th of a degree) at the centre of the curvature of the place
1NM = 6,080 feet = 1’ of latitude
11
Q
02 What is a statute mile (SM)?
A
An arbitrary unit of measurement which was set by law (ie a statute) in 1593 at 5,280 feet.
Not used in aviation navigation, but commonly used in meteorological visibility measurements.
This is the mile used for road distance in the US and UK
12
Q
02 What is a Kilometre (km)
A
1 kilometre = 1000 metres.
The metre was originally defined in 1793 as 1/10,000 of the average distance between the equator and the North pole.
Redefined in 1983 as the length of the path travelled by light in a vacuum in 1/299,792,458 of a second.
1Km = 3,280 feet
13
Q
02 _NM=_SM=_km
A
66 NM = 76 SM = 122 km
14
Q
03/04 What is direction?
A
The position of one point in space relative to another, without reference to the distance between them.
The angle that a line makes with some reference datum line passing through the point
Always measured clockwise from the datum
Always expressed in a THREE figure group
15
Q
03/04 What are the cardinal points?
A
North, South, East, West
16
Q
03/04 What are the quadrantal points?
A
North East, North West, South East, South West.
17
Q
03/04 Which system is used in air navigation? (Base 60)
A
The sexagesimal system. (Angular Distance in Degrees, Minutes, Seconds) Base of 60 (eg: 60 seconds in a minute)
Used for time and direction
18
Q
03/04 What is cardinal direction
A
East - The direction in which the earth is spinning
West - The direction opposite to East
North - The direction of the North Pole
South - The direction opposite to North
19
Q
03/04 What is true direction?
A
Direction measured with reference to the direction of the geographic North Pole.
20
Q
03/04 What is magnetic direction?
A
Direction measured with reference to the direction of Magnetic North at the place.
21
Q
03/04 Describe Magnetic Force?
A
There are 2 regions on the surface of a magnet where its attractive force for material like iron or steel is the greatest.
The attractive force is treated as if it emanates from 2 internal points called the poles.
22
Q
03/04 What is the magnetic meridian?
A
The direction of the horizontal component of the earth’s magnetic field at a point.
A compass needle will align itself with the magnetic meridian, pointing to the magnetic north pole. (powerpoint)
The vertical plane fixed by the direction of the line of force. It is also the direction taken by a perfect compass needle (notes section)
23
Q
03/04 What is secular change?
A
Average value changes in the Earth’s magnetic field over time, reflecting changes in the Earth’s core = unpredictable
24
Q
02 What are the radii at the equator and the poles?
A
6378 km and 6356 km
25
02 How many CT-142 does 402 Sqn have?
4
26
02 Where is 0 degrees longitude found?
Greenwich was chosen as the prime meridian in 1884 at the International Meridian Conference, defines 0° longitude.
27
03/04 What are the magnetic poles?
The poles are the position of the greatest field intensity. They are the projection onto the surface of the axis of the Earth's magnetic field.
28
03/04 What is a local anomaly?
The anomaly may be natural or it may be artificial. The magnitude depends on the nature of the magnetic material. The effects of these anomalies will decrease rapidly with height above the surface – approx the inverse cube of the distance.
29
03/04 Define annual variation?
When the average monthly values of the magnetic elements are corrected for the secular change, it is found that there is a small systematic change from month to month. For example the horizontal or ‘H’ component is stronger in summer.
30
03/04 Define daily change?
There is a small fluctuation of each of the magnetic elements, which repeats itself with some degree of regularity day after day, and is known as the daily change.
31
03/04 What is a magnetic storm?
Solar flares (sunspots) cause irregularities in the earth’s magnetic field.
32
03/04 Define soft iron magnetism?
Caused by the magnetism induced into soft material. The soft magnetic material of an aircraft is magnetized by induction of the magnetic field in which they lie. Consists of magnetic fields induced solely by the earth’s magnetic field.
33
03/04 Define isogonal?
A line on a map joining points of equal variation; not coincident with the magnetic meridian and therefore does not indicate the direction of the earth’s field at a point.
34
03/04 What is an agonic line?
A line on a map joining points of zero variation.
35
03/04 Define compass direction?
Direction measured with respect to compass north
36
03/04 What is deviation?
The horizontal angle between compass north and magnetic north
37
03/04 Explain the Best/Least rule?
Deviation West = Compass Best, Deviation East = Compass Least.
38
03/04 What is variation?
The angular difference between the magnetic meridian and the true meridian, at any point is called variation.
The horizontal angle between true north and magnetic north
39
03/04 Define hard iron magnetism?
The aircraft’s own magnetic field. This field is caused by the permanent magnetism resident in the aircraft’s structure and by the magnetism from onboard electrical systems.
40
03/04 What is compass north?
The direction taken by a compass needle.
41
03/04 Solve for MH and CH: TH = 138, VAR = 10E, DEV = 3E.
MH = 128, CH = 125.
42
05/06 What are three methods of expressing position on the Earth?
Place names, bearing and distance, grid names (GEOREF; LAT/LONG).
43
05/06 What is latitude?
Angular distance from the equator measured along a meridian. Units are Degrees° Minutes’ Seconds”. Winnipeg Intl is at 49°54’36”N.
44
05/06 What is longitude?
A semi-Great circle on the surface of the Earth joining the poles of the Earth. All meridians converge at the poles. Measures distance east or west of the prime meridian
45
05/06 How do you write latitude and longitude?
Latitude first (2 digits), then longitude (sometimes 3 digits). Except for GEOREF.
46
05/06 What time is used during aviation?
Zulu/ Universal Time Coordinate.
47
05/06 What is GEOREF?
A type of grid system - Earth is divided into sections (quadrangles). Consists of 288 sections, 15 degrees longitude by 15 degreees latitiude. (in the house, up the stairs).
48
07/09 What is conformality?
The correct representation of angles.
49
07/09 What is orthomorphism?
Shapes are perfectly defined in a small area.
50
07/09 What are the criteria for orthomorphism?
Conformal; scale is the same in all directions and angles are preserved.
51
07/09 What is scale?
A ratio of a given distance on a map to the actual distance on Earth.
52
07/09 How can you express scale?
Representative fraction; statement in words; graduated scale.
53
07/09 Compare a large and a small scale?
Large scale = small area, more detail; small scale = large area, less detail.
54
07/09 What are the three kinds of map projections?
Cylindrical, conical, and azimuthal/tangential.
55
07/09 What is an example of a cylindrical projection?
Mercator Projection (Transverse and Oblique Mercator included).
56
07/09 Describe the projection of a Transverse Mercator?
Line of tangency touches both poles and follows a meridian/anti-meridian.
57
07/09 Describe the projection of an Oblique Mercator?
Line of tangency is between any two points.
58
07/09 What is an example of a conical projection?
Lambert Conformal.
59
07/09 What is an example of an azimuthal projection?
Polar Stereo.
60
07/09 List the desirable map properties?
GRASSS (Great Circles straight, Rhumb Lines straight, Angles correct, Size correct, Shape Correct, Scale Correct and Constant)
61
07/09 What plotting charts are used in the CAF?
GNC, JNC, ONC, VNC (all are Lambert Conformal)
62
07/09 What are the scales for GNC, JNC, ONC, and VNC?
GNC 1:5 million; JNC 1:2 million; ONC 1: 1 million, VNC 1:500,000
63
10 What are the desirable properties of topographic maps?
Orthomorphic, conformal, and sufficient details
64
10 What are two common map projections used by the CAF?
Lambert Conformal (JNC, ONC, VNC) and Transverse Mercator (VTA 1:250,000)
65
10 What are the methods for showing relief?
Contour lines, spot heights, layer tinting, hill shading and hachures
66
10 What do close contour lines indicate?
A steep slope
67
10 How can you identify a spot height on a map?
A marked dot with the exact height.
68
10 How can you tell apart layers on a map?
The darker the colour, the higher the altitude.
69
10 How can you identify hill shading on a map?
One part of the hill will be slightly darker than the other.
70
10 What are hachures?
Short tapering lines drawn on the chart radiating from peaks.
71
10 What is important for pre flight preparation?
Draw intended lines on a topo map; number the maps in order of use; familiarize yourself with the route.
72
10 What are some important steps to remembering during flight?
Orient the map to the direction of flight; determine your current position; find a DR position; study the map to find a checkpoint/landmark; find the landmark on the radar screen.
73
10 List three steps to abide by during flight?
Watch (use as a physical step to determine location), Map (locate prominent checkpoint or landmark), and Radar (find landmark on screen)
74
11 List the advantages of the Jeppessen Computer?
Lightweight, no battery required, detachable parts, multipurpose and accurate
75
11 How to care for your Jeppessen Computer?
Keep away from excess heat and direct sunlight, occasionally clean between sides, use finger not an eraser to erase wind points, label computer where necessary, apply light coat of vaseline to wind side
76
12/13 What are the purposes of Mental Dead Reckoning?
Helps eliminate or catch gross errors, mentally figure out rough answer before using the Jepp, helps determine where to put decimal place and whether you have made a mistake
77
14/15 Define Velocity
"Rate of change of position in a given direction.
"
78
14/15 Define Vector
Graphical representation of a velocity
79
14/15 Define True Heading (TH)
Direction in which the aircraft is pointed relative to TRUE NORTH.
80
14/15 Define True Air Speed (TAS)
The speed of the aircraft (in knots) relative to the still air mass surrounding it.
81
14/15 Define Track Made Good (TMG)
The path of the aircraft over the ground.
82
14/15 Define Required Track (Rqd Tr)
The intended path of the aircraft over the ground.
83
14/15 Define Ground Speed (G/S)
The speed of the aircraft (in knots) relative to the ground.
84
14/15 Define Wind Velocity (W/V)
The direction and speed of the air mass over the ground. Direction is the true direction from which the wind is blowing. Speed is in knots.
85
14/15 Define Drift
The lateral movement imparted on to the aircraft by the wind.
86
14/15 Define Drift Angle (DA)
The angular difference between the true heading and the track. The drift angle is also referred to as “Crab Angle”.
87
03/04 Define relative direction
Direction measured clockwise from the nose of the aircraft
88
03/04 What is the bearing conversion
TB (true bearing) = RB (relative bearing) + TH (true heading)
89
14/15
90
14/15 ____ and ______ vectors start from the same point
air, ground
91
14/15 Wind blows from ___ vector to ____ vector
air, ground
92
11 How to use Jepp for multiplication for AxB:
line the outer number (A) with the 10 on the inner circle, look for the inner number on the wheel (B), so the answer lies on the outer circle, where the B is lined up with.
93
11 How to use the Jepp for division for A/B:
line the outer number (A) with the B on the inner circle, so the answer lies on the outer circle, where the 10 (on the inner circle) is lined up with.
94
12/13 How to use speed/time/distance with the Jepp:
Point the arrow on the inner circle to the speed;
the inner circle is the time (in minutes);
the outer circle based on time (on the inner circle) is the distance (on the outer circle)
95
12/13 How to use the Jepp for fuel calculations:
fuel flow is on the outer circle, lined up with the arrow on the inner circle;
the time is on the inner ring (in minutes);
the time on the inner circle points to the the fuel amount on the outer circle.
96
07/09 What are the limits of a Mercator chart?
Excessive scale expansion; enormous area distortion in higher latitudes; Great circles are plotted as curved lines.
97
07/09 What are the limits of a Polar Stereo Chart?
Works best for high latitudes (45-90 deg); too much distortion below 45 degrees to be viable.
98
07/09 What is a limit of a Lambert Conformal chart?
Limited to use near standard parallels due to distortion.
99
07/09 What are the polar stereo properties?
Parallels: Concentric, unequally spaced circles concave to nearer pole
Meridians: Straight lines, converging at the pole
Scale: Expands equally in all directions away from the pole
Shapes: Correct around the point of tangency distorted elsewhere
Great Circle: Approximately straight lines in polar region
Rhumb Line: Concave to the nearer pole
100
07/09 What are the Lambert Conformal properties?
Parallels: Concentric circles meet meridians at right angles
Meridians: Straight lines meet at the pole
Scale: Correct at two standard parallels (SP)
Between SPs – contracts
Outside SPs – expands
Considered correct over a single sheet
Shapes: Approximately preserved everywhere
Great Circles: Approximately straight lines
Rhumb Line: Concave to the nearest pole
101
07/09 What are the mercator projection properties?
Parallels: Straight lines, unequally spaced
Meridians: Straight lines, parallel, equally spaced
Scale: Correct at equator, expands away from equator
Shapes: Preserved (approx.) at equator, but distorts increasingly away from equator
Great Circle: Curved, convex to nearer pole
Rhumb Line: Straight lines
102
16/18 what is the wind component?
The along track component of the wind force that acts parallel to track, affecting the ground speed.
103
16/18 What is the drift component?
The cross track component of the wind force that acts perpendicular to track, affecting the aircraft’s drift.
104
16/18 What is the effective TAS?
The amount of TRUE AIR SPEED along the course. The head or tail wind component is added to this to give Ground Speed.
At small crab or drift angles, the ETAS is so close to the TAS that they may be considered the same. At crab or drift angles of 10° or greater, ETAS will be less than TAS.
105
16/18 If drift is less than 10° add ___ to TAS
wind component
106
20/21 What is mean sea level pressure as defined by ISA?
14.7 lbs/in^2, 101.3 kPa, 29.92 " Hg, or 1013.2 mb
107
20/21 How much pressure decreases as altitude increases?
.01"Hg for every 10 ft, 1"Hg for every 1000 ft, or 1 millibar for every 30 ft.
108
20/21 What is QNE?
Q code designator for standard pressure.
The altimeter sub-scale is set at the ISA pressure of 29.92" Hg.
The altimeter will then display what is known as pressure altitude, the altitude above the standard datum plane (mean sea level under ISA conditions).
109
20/21 What is QFE?
Q code designation for the observed pressure at an aerodrome corrected for temperature.
With QFE set on the sub-scale the altimeter will read zero on the surface of that aerodrome and will display height as the aircraft gains altitude.
Not used in Canada and the US, but it is used extensively in the UK.
110
20/21 What is QNH?
Q code designator for the barometric pressure in millibars or inches of Hg for a particular time and place, adjusted to MSL according to ISA.
Instead of reading zero on the ground, with QNH set on the sub-scale, the altimeter will read the height above mean sea level (MSL).
111
20/21 What is the threshold for altimeter serviceability?
± 50' with correct QNH set.
112
20/21 What is indicated altitude?
Altitude readout with QNH (height above mean sea level) set on the altimeter sub-scale.
113
20/21 What is pressure altitude?
Altitude readout with QNE (ISA 29.92” Hg) set on the altimeter sub-scale.
Used when above 18,000 ft ASL, when in the Standard Pressure Region (Northern Canada) and over the ocean.
The altitude and/or area in which QNE is used is dependent on national procedures and varies from country to country.
114
20/21 What is true altitude?
Actual height above mean sea level
Obtained by correcting indicated altitude for temperature
115
20/21 What is absolute altitude?
Actual height above terrain
Altitude readout with QFE (local aerodrome pressure) set on the altimeter sub-scale.
116
20/21 What is the relationship between true and indicated altitude...
A.In standard temperature?
B.In warmer temperature?
C.In colder temperature?
A.True and Indicated Altitude are the same.
B.True altitude is higher than indicated altitude,
C.True altitude is lower than indicated altitude.
117
20/21 What is the formula for pressure correction?
QNH-QNE x (10 feet for .01”Hg)
118
20/21 What is the formula for ISA temperature?
(Height/1000 x -2 Deg C) + 15 Deg C
119
20/21 What is the formula for ISA Deviation?
Outside Air Temperature - ISA Temperature = ISA Deviation
120
20/21 What is the formula for altitude error caused by ISA Dev?
(4 ft x °C ISA DEV x thousand feet ASL)
121
20/21 How do you find true altitude?
Indicated altitude - altitude error = true altitude
122
20/21 What is the temperature lapse in the ISA?
2 deg C per 1000 ft
123
24/25 How far back will the student provide the Hack Brief?
6 nm or 2 minutes away from the hack.
124
24/25 At what distances will the lead student advise the crew?
6, 3, 2, and 1 NM away from the TP/IP/target
125
24/25 What should you do if you plan on turning early?
Advise the pilots.
126
24/25 What will the Hack/Turning Point Brief consist of?
Description of TP to include ETA;
Outbound heading;
Distance to next point;
Time at next point;
Minimum IFR altitude;
climb/descent if required;
Hazards and Restrictions (any towers, airports, air traffic corridors or rising terrain in the vicinity of the first leg of the route that the crew should be aware of. (speed change, clearance or); and
Hack/TP brief complete.
127
24/25 What will the Target Brief consist of?
Description of Tgt to include ETA;
Tgt brief complete.
128
24/25 Explain the 5T Check?
Time: verbalize time on-top and note the difference (if applicable) from flight planned time
Turn: ensure the pilot turned to the briefed heading, then correct for drift using doppler information
Track: carry out a Track Angle Departure Check
Throttle: brief the pilot on the desired groundspeed
Talk: make a blind broadcast as required on 126.7
129
24/25 How many blind broadcasts are students required to make?
At least one.
130
24/25 Which remaining calls is the Lead responsible for?
Start crew;
Taxi call;
Airborne call;
Inbound call; and
Taxi in call.
131
24/25 True or False: The Lead Student is ALWAYS responsible for receiving, acknowledging, and identifying a potential traffic conflict to the pilot by calling either “conflict” or “no-conflict” on ICS.
True.
132
24/25 What do you say if the direction change is less than 10 degrees?
Pilot, alter heading #left/right
133
24/25 What do you say if the direction change is greater than 10 degrees?
Pilot, set heading ###º M
134
24/25 What do you say for a planned turn?
Pilot, turn right/left heading ###º M
135
24/25 What do you say for an easy turn?
Pilot, easy right/left (15 deg bank turn)
136
24/25 What do you say for a hard turn?
Pilot, hard right/left (30 deg bank turn)
137
24/25 What do you say if you want the pilot to level the wings?
Pilot, roll out now.
138
24/25 How do you conduct the LOST procedure?
(1) maintain a steady heading;
(2) review previous navigation;
(3) mark estimated position on map; and
(4) turn on ETA for turning point (TP).
139
24/25 How close to the track are you required to be?
5 NM for LLRN and 2 NM for LLIN.
140
24/25 How can you correct for drift on RADAR?
Mental Dead Reckoning or by using the Jepp.
141
24/25 What is the simplest way to make a speed adjustment?
Enter the distance left to go over how early/late you are. You will get the speed required to cover that distance in that time.
142
33-35 What factors affect altitude selection?
Direction of Flight
Transit distances
Icing
Winds
143
33-35 Can you fly the Ct-142 through ice?
Yes, but it is not recommended to sustain operations in moderate icing conditions
144
33-35 What is an equal time point?
A point on the intended track from which it will take the same amount of time to fly to either equal time point aerodrome.
145
33-35 What are the requirements for an equal time point?
1. Physically suitable for aircraft type (min 3000 x 100 hard surface with usable fuel available);
2. NOTAMs must be considered.
3.Depending on time of year, CRFI, de-icing, power cart etc must be taken into account; and
4. Forecast weather must be at or above the published landing minima for the approach aid serving the landing runway from one hour before earliest arrival time to one hour after the latest arrival time at the ETP aerodrome.
146
36 What are your hourly en route requirements?
System check
Fuel analysis
HF position report
147
36 Which student is lead out/inbound?
S3 – Lead out
S2 – Lead inbound
148
37 For flight planning purposes, how much fuel do we allocate for taxiing?
200lbs
149
37 For determining magnetic tracks on a given leg, where is variation measured?
Mid-track
150
37 three hourly requirements that ACSO students are responsible for:
Fuel analysis
Systems checks (same as EOC check)
Position reports (covered under Comms)
151
37 NAVAIDs should be:
Diversified
In range
Geographically separated
152
37 When can the lead calculate ETAs?
cleared on course;
abeam navaid / aerodrome (as applicable); and
above 100 nm safe altitude, or when safely able if not flying above the 100 nm safe altitude.
153
37 What is the purpose of an EOC check?
Confirms the accuracy of the navigation computers and which will be the primary source of navigation
154
37 When can you start your EOC check?
When the aircraft is +/-30° from the on course and above safety altitude
155
37 What does the Lead say to the pilot after completing the EOC check?
“Pilot, Lead, computers have been assessed, GPS (or INS) is primary, we are in transit, you have the nav.”
156
38 XTK
Cross Track Distance Error.
cross track distance to a tenth of a NM of track.
157
38 TKE
Cross Track Angle Error
track angle error to a tenth of a degree L (left) or R (right) of track
158
38 List the 6 steps you use to help assist you when navigating to the TP/IP/TGT
1 Check your From/To waypoints and ensure proper navigation is set.
2 Check where you are compared to your desired track (XTK)
3 Check if the aircraft is opening/closing your track (TKE)
4 Determine heading correction to maintain/regain track
5 Pass the heading to the pilots
6 With the help of computer info (DTG/TTG), identify your RADAR point and adjust for speed.
159
38 What are the 2 preferred methods for speed correction during LLIN and what piece of info do you use from the computer
MDR and Jepp. Use time to go info displayed on your systems
160
39-40 What do you use on the GPS/INS DID to maintain/correct track?
XTK and TKE
161
39-40 What are the duties of an ACSO during departure and arrival?
assist the pilot;
ensure clearances are followed; and
ensure the clearances do not present a hazard to the aircraft. This will require developing an air picture in the terminal area
162
41 What are the requirements for an airfield to be considered useable for ETP purposes?
Suitable Rwy size with required services
No NOTAMs precluding its use
Suitable CRFI.
Forecast Weather must be at or above landing minima 1 hr before the earliest arrival time to 1 hr after the latest arrival time at the ETP aerodrome.
163
41 Which wind chart do you use for ETP calculations?
10000’ (CF Weather Office) or 9000’ (NavCanada)
164
41 What are some of the purpose of a brief?
Provide all crew members with information about the mission
Ensure all crew members are on the same page regarding the conduct of the mission
Sets the tone of professionalism and conduct that is expected throughout the mission
Briefs are intended to be brief. Excessive detail (eg lat/long of your target) should be avoided
165
44-45 Why is fuel monitoring important
To ensure there is enough fuel to complete the mission.
To spot fuel leaks early.
To check that aircraft fuel consumption matches predicted consumption.
To be aware of fuel remaining in order to respond quickly to diversions or re-taskings.
166
44-45 Cruise control
The organized control of an aircraft in flight to obtain maximum flight profile efficiency
167
44-45 cruise control advantages
General increase in safety and efficiency during individual flights
Conservation of fuel on ferry flights
Optimize payloads on transport operations
Saving on fuel in long range tactical flights where the time spent in actual combat is small in relation to time spent cruising to and from target
Efficient fuel conservation on long range flights where maximum range is required
Controls may be adjusted properly in flight to meet any changes in predicted conditions (W/V, ramp time, ease of operation).
168
44-45 cruise control factors
Distance
Wind component
Temperature deviation
Fuel capacity
Payload to be carried
Amount of fuel reserve required
Max allowable all-up weight at T/O and landing
Enroute weather
ATC restrictions
Fuel availability at departure and destination
169
44-45 maximum endurance
Operation of an aircraft at a specific SPEED and ALTITUDE, to achieve the lowest fuel flow, and thus the maximum time airborne.
170
44-45 maximum range
Operation of an aircraft at a specific SPEED and ALTITUDE, to achieve the maximum ground range per pound of fuel, for a given fuel load.
171
44-45 specific fuel consumption (SFC)
One measure of the efficiency of an engine is Specific Fuel Consumption.
Specific Fuel Consumption is defined as the comparison of the amount of fuel used to the amount of thrust produced
The lower the SFC the better, since the aim is to obtain the maximum amount of thrust from fuel used.
172
44-45 Four Variables Affecting SFC
Engine RPM
OAT
Altitude
IAS
SFC = FF / ESHP
173
44-45 ESHP SUMMARY
UP RPM = UP ESHP
UP TEMP = DOWN ESHP
UP ALT = DOWN ESHP
UP IAS = UP ESHP
174
44-45 SFC SUMMARY
OPTIMUM RPM = DOWN SFC
UP TEMP = UP SFC
UP ALT = DOWN then UP SFC
UP IAS = DOWN SFC
175
44-45 HOW TO GET MAXIMUM RANGE
RPM: Operate engines at Max Continuous RPM (Optimum RPM)
ALTITUDE: Fly high altitudes (up to service ceiling)
IAS: Fly Long Range Cruise Speed
TEMP: Can’t do much about this one!
176
44-45 WHAT IS SPECIFIC AIR RANGE
SAR is a measure of the efficiency with which an aircraft flies through the air.
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44-45 WHAT IS SPECIFIC GROUND RANGE
SGR is a measure of the efficiency with which an aircraft flies over the ground.
178
44-45 What are some of the corrective actions we can take to rectify a lower-than-planned fuel situation?
Change SPEED to LRC – improve SGR
Change LEVEL – improve SGR
Change ALTERNATE – lower MIN DIV Fuel
Change ROUTE – shorter route saves fuel
Change DESTINATION – divert for refuel
179
44-45 What factors could affect the planned fuel burn?
ISA conditions not as planned
Winds different from planned
Aircraft not performing to specifications
Fuel leak
Weather avoidance
ATC re-routing
180
44-45 There are numerous factors that affect our decision on cruise control. What are they?
Distance
wind component
Temperature deviation
Fuel capacity
Payload to be carried
Amount of fuel reserve required
Max allowable all-up weight at T/O and landing
Enroute weather
ATC restrictions
Fuel availability at departure and destination aerodrome
181
44-45 What is the purpose of fuel monitoring?
Ensure there is enough fuel to complete mission.
To spot fuel leaks early.
To check that aircraft fuel consumption matches predicted consumption.
To be aware of fuel remaining in order to respond quickly to diversions or re-tasking.
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