CPL Practice Exam 4

Special VFR Flight

602.117 (1) Despite paragraph 602.114(b), an aircraft may be operated in special VFR flight within a control zone if

(a) weather conditions preclude compliance with paragraph 602.114(b);

(b) flight visibility is not less than

(i) 1 mile, where the aircraft is not a helicopter, or

(ii) one-half mile, where the aircraft is a helicopter;

(c) the aircraft is operated clear of cloud and with visual reference to the surface at all times; and

(d) authorization to do so has been requested and obtained from the appropriate air traffic control unit.

(2) Where aerodrome traffic permits, an air traffic control unit shall authorize a pilot-in-command to operate an aircraft in special VFR flight within a control zone if

(a) the pilot-in-command requests authorization to operate the aircraft in special VFR flight;

(b) when reported, ground visibility within the control zone is not less than

(i) 1 mile, where the aircraft is not a helicopter, or

(ii) one-half mile, where the aircraft is a helicopter;

(c) the aircraft is equipped with radiocommunication equipment capable of maintaining communication with the appropriate air traffic control unit; and

(d) the aircraft is not a helicopter and is operated during the night, and the authorization is for the purpose of allowing the aircraft to land at the destination aerodrome.

Maximum Flight Time

700.27 (1) An air operator shall not assign flight time to a flight crew member, and a flight crew member shall not accept such an assignment, if the member’s total flight time will, as a result, exceed

(a) 112 hours in any 28 consecutive days;

(b) 300 hours in any 90 consecutive days;

(c) 1,000 hours in any 365 consecutive days; or

(d) in the case of a single-pilot operation, 8 hours in any 24 consecutive hours.

(2) For the purpose of subsection (1), a flight crew member’s flight time includes

(a) the flight time accumulated from other flight operations; and

(b) the total flight time of a flight with an augmented flight crew.

AIM RAC 2.8.6 Class F Airspace

Class F airspace is airspace of defined dimensions within which activities must be confined because of their nature, and within which limitations may be imposed upon aircraft operations that are not a part of those activities.

Class F airspace may be restricted airspace, advisory airspace, military operations areas, or danger areas and can be controlled airspace, uncontrolled airspace, or a combination of both.

Unless otherwise specified, the rules for the surrounding airspace apply in areas of Class F airspace, no matter if these areas are active or inactive.

Class F airspace is designated in the DAH (TP 1820) and published on the appropriate aeronautical charts.

CAR 602.62 Life Preservers and Flotation Devices

(1) No person shall conduct a take-off or a landing on water in an aircraft or operate an aircraft over water beyond a point where the aircraft could reach shore in the event of an engine failure, unless a life preserver, individual flotation device or personal flotation device is carried for each person on board.

(2) No person shall operate a land aeroplane, gyroplane, helicopter or airship at more than 50 nautical miles from shore unless a life preserver is carried for each person on board.

(3) No person shall operate a balloon at more than two nautical miles from shore unless a life preserver, individual flotation device or personal flotation device is carried for each person on board.

(4) Subject to subsection (5), for aircraft other than balloons, every life preserver, individual flotation device and personal flotation device referred to in this section shall be stowed in a position that is easily accessible to the person for whose use it is provided, when that person is seated.

(5) In cases where infant life preservers are carried on board an aircraft operated with flight attendants on board, the infant life preservers may be stowed in bulk in a location that is easily accessible to the flight attendants if

(a) the location is adjacent to a ditching emergency exit and is clearly marked as the stowage location for infant life preservers; and

(b) the operator has established procedures that require flight attendants to distribute an infant life preserver to each passenger responsible for an infant when preparing for a ditching.

602.63 Life Rafts and Survival Equipment — Flights over Water

(1) No person shall operate over water a single-engined aeroplane, or a multi-engined aeroplane that is unable to maintain flight with any engine failed, at more than 100 nautical miles, or the distance that can be covered in 30 minutes of flight at the cruising speed filed in the flight plan or flight itinerary, whichever distance is the lesser, from a suitable emergency landing site unless life rafts are carried on board and are sufficient in total rated capacity to accommodate all of the persons on board.

(2) Subject to subsection (3), no person shall operate over water a multi-engined aeroplane that is able to maintain flight with any engine failed at more than 200 nautical miles, or the distance that can be covered in 60 minutes of flight at the cruising speed filed in the flight plan or flight itinerary, whichever distance is the lesser, from a suitable emergency landing site unless life rafts are carried on board and are sufficient in total rated capacity to accommodate all of the persons on board.

(3) A person may operate over water a transport category aircraft that is an aeroplane, at up to 400 nautical miles, or the distance that can be covered in 120 minutes of flight at the cruising speed filed in the flight plan or flight itinerary, whichever distance is the lesser, from a suitable emergency landing site without the life rafts referred to in subsection (2) being carried on board.

(4) No person shall operate over water a single-engined helicopter, or a multi-engined helicopter that is unable to maintain flight with any engine failed, at more than 25 nautical miles, or the distance that can be covered in 15 minutes of flight at the cruising speed filed in the flight plan or flight itinerary, whichever distance is the lesser, from a suitable emergency landing site unless life rafts are carried on board and are sufficient in total rated capacity to accommodate all of the persons on board.

(5) No person shall operate over water a multi-engined helicopter that is able to maintain flight with any engine failed at more than 50 nautical miles, or the distance that can be covered in 30 minutes of flight at the cruising speed filed in the flight plan or flight itinerary, whichever distance is the lesser, from a suitable emergency landing site unless life rafts are carried on board and are sufficient in total rated capacity to accommodate all of the persons on board.

(6) The life rafts referred to in this section shall be

(a) stowed so that they are easily accessible for use in the event of a ditching;

(b) installed in conspicuously marked locations near an exit; and

(c) equipped with an attached survival kit, sufficient for the survival on water of each person on board the aircraft, given the geographical area, the season of the year and anticipated seasonal climatic variations, that provides a means for

(i) providing shelter,

(ii) providing or purifying water, and

(iii) visually signalling distress.

(7) Where a helicopter is required to carry life rafts pursuant to subsection (4) or (5), no person shall operate the helicopter over water having a temperature of less than 10^oC unless

(a) a helicopter passenger transportation suit system that conforms to paragraph 551.407(c) of the Airworthiness Manual is provided for each passenger on board;

(b) a helicopter crew member transportation suit system is provided for each crew member on board; and

(c) the pilot-in-command directs all persons on board to wear their helicopter transportation suit system.

(8) Every person who has been directed to wear a helicopter transportation suit system pursuant to paragraph (7)(c) shall wear that suit system.

(9) Paragraph (7)(a) does not apply if

(a) the flight is necessary in order to respond to a medical emergency or any other emergency that is a threat to the safety of persons and

(i) the helicopter is a transport category rotorcraft, in respect of which a type certificate has been issued, that meets the requirements of Chapter 529 — Transport Category Rotorcraft of the Airworthiness Manualthat are applicable to Category A rotorcraft,

(ii) there is insufficient time before the flight to acquire a helicopter passenger transportation suit system of the appropriate size for each passenger, and

(iii) there is a crew member in the cabin for the duration of the flight who is trained to assist passengers in an emergency evacuation in the event of a landing in water and who is able to come to the assistance of passengers; or

(b) there is a medical reason that prevents a passenger from wearing a helicopter passenger transportation suit system.

(10) A passenger who is not wearing a helicopter passenger transportation suit system for a reason referred to in subparagraph (9)(a)(ii) or paragraph (9)(b) shall be provided with a life preserver and the pilot-in-command shall direct the passenger to wear the life preserver for the duration of the flight if they are physically and medically able to do so.

AIM RAC 3.11 CLOSING A FLIGHT PLAN

In order to comply with CAR 602.77, an arrival report for a flight plan shall be submitted to an ATC unit, an FSS (or a FIC) or a CARS as soon as practicable after landing but not later than:

(a)  the SAR time specified in the flight plan; or

(b)  where no SAR time is specified in the flight plan, one hour after the last reported ETA.

A pilot who terminates a flight itinerary shall ensure that an arrival report is filed with an ATC unit, an FSS (or a FIC), a CARS or, where the flight itinerary was filed with a responsible person, the responsible person as soon as practicable after landing but not later than:

(a)  the SAR time specified in the flight itinerary; or

(b)  where no SAR time was specified in the flight itinerary, 24 hours after the last reported ETA.

A pilot who terminates an IFR flight at an aerodrome where there is an operating ATC unit, FSS or where RAAS is provided, is not required to file an arrival report unless requested to do so by the appropriate ATC unit or FSS.

When submitting an arrival report, the pilot should clearly indicate that he/she was operating on a flight plan or flight itinerary and wishes it to be closed. Failure to close a flight plan or flight itinerary will initiate SAR action. It should not be assumed that ATS personnel will automatically file arrival reports for VFR flights at locations served by control towers and FSSs or an RCO. Toll-free calls, as outlined in the CFS, may be made to an ATS facility for this purpose.

CAR 602.70 Flight Preparation, Flight Plans and Flight Itineraries

602.70 In this Division, overdue, in respect of an aircraft, means an aircraft for which an arrival report has not been filed

(a) where a flight plan has been filed in respect of the aircraft,

(i) if a search and rescue notification time is specified in the flight plan, immediately after the last reported such time, or

(ii) in all other cases, within one hour after the last reported estimated time of arrival, or

(b) where a flight itinerary has been filed in respect of the aircraft,

(i) if a search and rescue notification time is specified in the flight itinerary, immediately after the last reported such time, or

(ii) in all other cases, within 24 hours after the last reported estimated time of arrival; (en retard)

responsible person means an individual who has agreed with the person who has filed a flight itinerary to ensure that the following are notified in the manner prescribed in this Division, if the aircraft is overdue, namely,

(a) an air traffic control unit, a flight service station or a community aerodrome radio station, or

(b) a Rescue Co-ordination Centre. (personne de confiance)

Aircraft Icing

602.11 (1) In this section, critical surfaces means the wings, control surfaces, rotors, propellers, horizontal stabilizers, vertical stabilizers or any other stabilizing surfaces of an aircraft, as well as any other surfaces identified as critical surfaces in the aircraft flight manual.

(2) No person shall conduct or attempt to conduct a take-off in an aircraft that has frost, ice or snow adhering to any of its critical surfaces.

(3) Despite subsection (2), a person may conduct a take-off in an aircraft that has frost caused by cold-soaked fuel adhering to the underside or upper side, or both, of its wings if the take-off is conducted in accordance with the aircraft manufacturer’s instructions for take-off under those conditions.

(4) Where conditions are such that frost, ice or snow may reasonably be expected to adhere to the aircraft, no person shall conduct or attempt to conduct a take-off in an aircraft unless

(a) for aircraft that are not operated under Subpart 5 of Part VII,

(i) the aircraft has been inspected immediately prior to take-off to determine whether any frost, ice or snow is adhering to any of its critical surfaces, or

(ii) the operator has established an aircraft inspection program in accordance with the Operating and Flight Rules Standards, and the dispatch and take-off of the aircraft are in accordance with that program; and

(b) for aircraft that are operated under Subpart 5 of Part VII, the operator has established an aircraft inspection program in accordance with the Operating and Flight Rules Standards, and the dispatch and take-off of the aircraft are in accordance with that program.

(5) The inspection referred to in subparagraph (4)(a)(i) shall be performed by

(a) the pilot-in-command;

(b) a flight crew member of the aircraft who is designated by the pilot-in-command; or

(c) a person, other than a person referred to in paragraph (a) or (b), who

(i) is designated by the operator of the aircraft, and

(ii) has successfully completed training relating to ground and airborne icing operations under Subpart 4 or relating to aircraft surface contamination under Part VII.

(6) Where, before commencing take-off, a crew member of an aircraft observes that there is frost, ice or snow adhering to the wings of the aircraft, the crew member shall immediately report that observation to the pilot-in-command, and the pilot-in-command or a flight crew member designated by the pilot-in-command shall inspect the wings of the aircraft before take-off.

(7) Before an aircraft is de-iced or anti-iced, the pilot-in-command of the aircraft shall ensure that the crew members and passengers are informed of the decision to do so.

AIM AIR

AIM RAC 3.11 CLOSING A FLIGHT PLAN

In order to comply with CAR 602.77, an arrival report for a flight plan shall be submitted to an ATC unit, an FSS (or a FIC) or a CARS as soon as practicable after landing but not later than:

(a)  the SAR time specified in the flight plan; or

(b)  where no SAR time is specified in the flight plan, one hour after the last reported ETA.

A pilot who terminates a flight itinerary shall ensure that an arrival report is filed with an ATC unit, an FSS (or a FIC), a CARS or, where the flight itinerary was filed with a responsible person, the responsible person as soon as practicable after landing but not later than:

(a)  the SAR time specified in the flight itinerary; or

(b)  where no SAR time was specified in the flight itinerary, 24 hours after the last reported ETA.

A pilot who terminates an IFR flight at an aerodrome where there is an operating ATC unit, FSS or where RAAS is provided, is not required to file an arrival report unless requested to do so by the appropriate ATC unit or FSS.

When submitting an arrival report, the pilot should clearly indicate that he/she was operating on a flight plan or flight itinerary and wishes it to be closed. Failure to close a flight plan or flight itinerary will initiate SAR action. It should not be assumed that ATS personnel will automatically file arrival reports for VFR flights at locations served by control towers and FSSs or an RCO. Toll-free calls, as outlined in the CFS, may be made to an ATS facility for this purpose.

CAR 602.70 Flight Preparation, Flight Plans and Flight Itineraries

602.70 In this Division, overdue, in respect of an aircraft, means an aircraft for which an arrival report has not been filed

(a) where a flight plan has been filed in respect of the aircraft,

(i) if a search and rescue notification time is specified in the flight plan, immediately after the last reported such time, or

(ii) in all other cases, within one hour after the last reported estimated time of arrival, or

(b) where a flight itinerary has been filed in respect of the aircraft,

(i) if a search and rescue notification time is specified in the flight itinerary, immediately after the last reported such time, or

(ii) in all other cases, within 24 hours after the last reported estimated time of arrival; (en retard)

responsible person means an individual who has agreed with the person who has filed a flight itinerary to ensure that the following are notified in the manner prescribed in this Division, if the aircraft is overdue, namely,

(a) an air traffic control unit, a flight service station or a community aerodrome radio station, or

(b) a Rescue Co-ordination Centre. (personne de confiance)

VFR Over-the-Top

602.116 Despite paragraphs 602.114(a) and 602.115(a), an aircraft may be operated in VFR OTT flight during the cruise portion of the flight during the day if

(a) the aircraft is operated at a vertical distance from cloud of at least 1,000 feet;

(b) where the aircraft is operated between 2 cloud layers, the vertical distance between the layers is at least 5,000 feet;

(c) flight visibility at the cruising altitude of the aircraft is at least 5 miles; and

(d) the weather at the aerodrome of destination is forecast to have no broken, overcast or obscured layer lower than 3,000 feet above the planned flight altitude and the ground visibility is forecast to be five miles or greater with no thunderstorms or precipitation

(i) where the forecast is an aerodrome forecast (TAF), for the period from 1 hour before to 2 hours after the estimated time of arrival, using the worst forecast condition together with any of the references TEMPO (temporary fluctuation), BECMG (becoming) or PROB (probability), and

(ii) where an aerodrome forecast (TAF) is not available and the forecast is an area forecast (FA), for the period from 1 hour before to 3 hours after the estimated time of arrival.

Definitions:

day or daylight means the time between the beginning of morning civil twilight and the end of evening civil twilight; (jour)

night means the time between the end of evening civil twilight and the beginning of morning civil twilight; (nuit)

AIM RAC 2.8.3

Reference: CAR 605.31 Oxygen Requirements for Pressurized Aircraft

All crew members and 10 per cent of passengers and, in any case, no less than one passenger.

(a) Entire period of flight exceeding 30 minutes at cabin-pressure-altitudes above 10,000 feet ASL but not exceeding 13,000 feet ASL

(b) Entire period of flight at cabin-pressure-altitudes above 13,000 feet ASL

Reference CARs 605.32

(1) Where an aircraft is operated at cabin-pressure-altitudes above 10,000 feet ASL but not exceeding 13,000 feet ASL, each crew member shall wear an oxygen mask and use supplemental oxygen for any part of the flight at those altitudes that is more than 30 minutes in duration.

(2) Where an aircraft is operated at cabin-pressure-altitudes above 13,000 feet ASL, each person on board the aircraft shall wear an oxygen mask and use supplemental oxygen for the duration of the flight at those altitudes.

(3) The pilot at the flight controls of an aircraft shall use an oxygen mask if

(a) the aircraft is not equipped with quick-donning oxygen masks and is operated at or above flight level 250; or

(b) the aircraft is equipped with quick-donning oxygen masks and is operated above flight level 410.

Determine the cloud base given that the surface temperature is 25°C and the dewpoint of 10°C?

Method 1:
Cloud base = (Temperature – Dew point) / 2.5 × 1000 + elevation
Cloud base = (25 – 10) / 2.5 × 1000 + 0
Cloud base = 15 / 2.5 × 1000 + 0
Cloud base = 6 × 1000 + 0
Cloud base = 6,000 ft

Note: The Dry Adiabatic lapse rate (DALR) is 3° for every 1,000′ dewpoint depression of 0.5° per thousand feet, nets 2.5° per thousand feet.

Note: Dewpoint depression is the difference between the original dew point and the dew point achieved after some of the water vapor is removed.

Method 2: 
Cloud base = Temperature – Dew point x 406 
Cloud base = 25-10 x 406
Cloud base = 15 x 406
Cloud base = 6,090 feet

Note: 406 is a constant. Note: A mathematical constant is a number whose value is fixed.

In both the Type K and J systems. The lights remain on for 15 mins

ARCAL Type K

Key the microphone 7 times initially.

Then 3 times for low intensity. or 5 times within 5 seconds for medium or 7 times for high intensity. All must be done within 5 seconds.

ARCAL Type J

Key the microphone 7 times within 5 seconds

Radiation fog is formed on clear nights with light winds. The ground cools losing heat through radiation. The air in direct contact with the earth’s surface is cooled. If the air is moist and the temperature is lowered below the dewpoint, fog will form.

The primary conditions conducive to the formation of radiation fog include:

1. Clear Skies and Light Winds: Clear skies allow for efficicent radiative cooling of the Earth’s surface, while light winds prevent the mixing of the air near the surface.
2. Cooling of the surface: The near surface air cool rapidly during the nighttime and this cooling causes the air temperature to drop to the dew point temperature, leading to the condensation of water vapor and the formation of fog.
3. Moist air

STATION PRESSURE

Station pressure is the actual atmospheric pressure at the elevation of the observing station. It is, in other words, the actual weight of a column of air extending up from the station level to the outer limit of the atmosphere. The value is determined directly from the mercury barometer at the observing station.

For example: The weight of the atmosphere decreases with altitude, the atmospheric pressure reading at a station at 5.000 feet elevation will be less than that at a station at 1,000 feet and still less than that at a station at sea level.

MEAN SEA LEVEL PRESSURE

Pressure altitude is the altitude corrected for non-standard pressure. It is used to determine your aircraft’s performance on a non-standard day. The standard used for pressure at sea level is 29.92 in Hg, inches of mercury.

A non-standard day is a day where the pressure is not 29.92inHg

Pressure altitude is the attitude displayed on the altimeter when the Kollsman window is set to 29.92 inches of mercury or 1013.4 millibars.

There are 2 quick ways besides using an E6B/CX3:

Obtain it through either reading the altitude when you set 29.92 in the altimeter; or.

Calculate it manually:

1. Subtract the current altimeter setting from the standard pressure of 29.92.
2. Multiply by 1,000.
3. If you have a negative number, subtract it from the field elevation. Add a positive number.

There is often little temperature change at the surface as an upper level front passes.

Upper-level fronts by themselves are not associated with much surface weather, but they are quite significant for aviation forecasting.
The zone of an upper-level front often features strong turbulence excited by strong vertical wind shear, so commercial aircraft generally try to avoid them.

Upper-level fronts are most often found in the vicinity of strong jet streams.

A constant speed prop keeps a constant RPM with the aircraft’s chancing pitch attitude.

Basically, there are 2 types of constant speed props. One that relies on counterweights and the other that is hydromatic.

During an engine failure, therefore loss of oil pressure.

1) With a counterweight constant speed prop
If oil pressure is lost during flight, the propeller will automatically go into a full coarse pitch position where the blades stop turning and are streamlined with the airflow to reduce drag. This is used on twin engine aircraft.

2) With a hydromatic constant speed prop
If oil pressure is lost during flight, the propeller will automatically go into full fine pitch, enabling the engine to develop the most power that it can and to achieve the best performance under the circumstances. This type of propeller is used in single-engine aircraft.

As carburetor heat is applied, the manifold pressure will decrease and the mixture enriches initially. This occurs because the hot air entering the carburetor is less dense than the cold air, leading to a richer fuel-air mixture. As the ice melts and clears, engine power should gradually return to normal, and engine smoothness should improve.

Magnetic Dip

Magnetic dip creates the most substantial errors in a compass. As you get closer to the North or South Pole, magnetic flux lines point downwards towards the poles, and your compass magnets dip towards the low side of a turn. When magnetic dip is pronounced, it’s difficult to get actual readings. This error isn’t much of a problem near the equator, where your compass points more or less horizontally and magnetic dip isn’t a concern.

Acceleration And Deceleration Error

Another major problem with magnetic compasses in airplanes is acceleration error. In the Northern Hemisphere, as you accelerate, your compass will show a turn to the North. And as you decelerate, your compass will show a turn to the South. When the speed stabilizes, the compass returns to normal. This error is greatest on East or West headings.

Use the acronym ANDS: “Accelerate-North, Decelerate-South.”

Turning Errors

During a turn from a Northerly heading, the compass briefly indicates a turn in the opposite direction. As for aircraft turning from a Southerly heading, the compass indicates a turn in the correct direction, but at a faster rate than is actually being turned.

Use the acronym NOSE: “North-Opposite, South-Exaggerated.”

Wing and Ball at the same direction: Slipping turn

Wing and Ball different directions: Skidding turn

Wing either to the right or left and ball centered: coordinated turn

3 gallons climb, 10 gallons start and taxi, 18 gallons cruise, 4.5 gallons day reserve = 35.5 gallons 

OAT: 10°C, Pressure altitude: 8,000, TAS: 125, then CAS = 110 kts

15 mins start and taxi, 9 mins climb, 120 mins cruise = 0924Z

3 gallons climb, 10 gallons start and taxi, 18 gallons cruise, 4.5 gallons day reserve = 35.5 gallons 

AIM COM 4.7 Distance Measuring Equipment (DME) 

The DME slant range error is the greatest when the airplane is at a high altitude close to or over the ground station. Moreover, slant range error also affects groundspeed and time-to-staion displays when you are close to the station.

Reference From the Ground Up 7.4

Lambert Conformal Conic — Useful for long distances because a straight line on the map is very close to a great circle course. Most VFR charts are Lambert Conformal Conic.

Mercator — The most commonly used projection for navigating in small areas because of its accuracy and the fact that a straight line is also a rhumbline.

Low level airspace and Air Routes

What is low-level airspace?

All airspace within the Canadian Domestic Airspace (CDA) below 18,000 ft ASL

What is a low-level airway?

Low level airways, starts from 2,200 ft AGL up to, but not including, 18,000 ft ASL.

An airway is within Class E controlled airspace.

What is a low-level air route?

Low-level air routes, starts from the surface of the earth upwards until ATC service is not provided.

An air route is within Class G uncontrolled airspace. ATC separation is not provided to IFR or VFR aircraft

Pilots operating VFR en route in uncontrolled airspace should continuously monitor 126.7 MHz when not communicating on the MF or ATF.

How are they depicted on a  LO Chart?

Controlled Airspace:

If it is based on a VHF/UHF navaid, the line is black. If it is based on a LF/MF navaid, the line is green.

Controlled low level airways based on a VOR/TACAN/VORTAC are depicted as black lines with the letter V for Victor airways. Controlled low level airway based on an NDB are green lines.

This is a controlled low level GNSS RNAV route. They are called T routes, which are low-level controlled fixed RNAV routes

Un-controlled airspace

Un-controlled air routes are depicted as a dashed line and a dot. VHF air routes are black and NDB air routes are green.

This is an uncontrolled GNSS RNAV route. The are called L-routes, which are low-level uncontrolled fixed RNAV routes

Summary:

An airway is in controlled airspace.
An air route is in uncontrolled airspace.

Air airway begins at 2200 AGL up to 17,999 ft.
An air route begins at the surface up to 17,999 ft.

Airway and air route don’t overlie each other (are not on layered top of each other). They are separate navigation “roads” within the sky that might intersect/criss cross each other.

Handbook for Civil aviation Medical Examiners

Hypoxia is an insidious killer. There is a tendency for euphoria to develop while motor skills and reasoning abilities deteriorate. The result is that in many cases the pilot may become seriously hypoxic without appreciating that there is a problem. To the observer tachypnea, cyanosis, mental confusion and loss of muscle coordination are obvious. To the pilot however, the only symptoms may be slight dyspnea, dizziness, fatigue, decreasing vision and finally loss of muscular control. Night vision can be impaired at as low as 5000 ft. Tolerance to hypoxia varies from individual to individual and from time to time. Tolerance can be increased by continual exposure to high altitudes and varies with the level of the hemoglobin and the oxygen carrying capacity of the blood. It is decreased by fatigue, cold and poor physical conditioning. Even at 5,000 ft. night vision is decreased.

Types

Hypoxia is generally divided into four types.

Hypoxic hypoxia is due to a decrease in the oxygen available to the body such as typically occurs with altitude.

Hypemic hypoxia is caused by a reduction in the oxygen carrying capacity of the blood for any reason. It also occurs when hemoglobin is saturated by gases for which it has a higher affinity, the most common of which is carbon monoxide. This is not only produced by exhaust leaks into the cockpit but also by cigarette smoking. Carbon monoxide is a product of incomplete combustion and may be present at levels of 6-8% in the blood of a heavy smoker and such individuals may become significantly hypoxic at levels below 10,000 ft.

Stagnant hypoxia is a less common problem caused by a reduction in total cardiac output, pooling of the blood or restriction of blood flow. Heart failure, shock, continuous positive pressure breathing and Gforces in flight can create stagnant hypoxia. Local stagnant hypoxia can occur with tight and restrictive clothing or, in the cerebral circulation, in association with vasoconstriction due to respiratory alkalosis provoked by hyperventilation.

Histotoxic hypoxia refers to poisoning of the respiratory cytochrome system by chemicals such as cyanide or carbon monoxide but it can also be caused by the effects of alcohol. Needless to say a pilot in poor physical condition, recovering from a hangover and smoking while in flight can quickly become an unfortunate statistic!

AIM COM 4.7 Distance Measuring Equipment (DME) 

The DME slant range error is the greatest when the airplane is at a high altitude close to or over the ground station. Moreover, slant range error also affects groundspeed and time-to-staion displays when you are close to the station.

AIM COM 4.8 TACTICAL AIR NAVIGATION (TACAN)

Tactical air navigation aid (TACAN) is a navigation aid (NAVAID) used primarily by the military for en route, non-precision approaches (NPAs) and other military applications. It provides azimuth in the form of radials and slant distance in nautical miles (NM) from the ground station. The system operates in the ultrahigh frequency (UHF) range with the frequencies identified by channel number.

TACAN users may obtain distance information from a distance measuring equipment (DME)  that is paired with the VHF omnidirectional range (VOR). This TACAN paired channel number is published in the Canada Flight Supplement (CFS) for every VOR/DME facility.

CAUTION:
Only DME information is being received by the TACAN avionics. Any apparent radial information obtained through the TACAN avionics from a VOR/DME facility can only be false signals.

Unserviceable and Removed Equipment — General

605.08 (1) Despite subsection (2) and sections 605.09 and 605.10, no person shall conduct a take-off in an aircraft that has equipment that is not serviceable or from which equipment has been removed if, in the opinion of the pilot-in-command, aviation safety is affected.

(2) Despite sections 605.09 and 605.10, a person may conduct a take-off in an aircraft that has equipment that is not serviceable or from which equipment has been removed where the aircraft is operated in accordance with the conditions of a flight permit that has been issued specifically for that purpose.

Unserviceable and Removed Equipment — Aircraft with a Minimum Equipment List

605.09 (1) Subject to subsection (2), where a minimum equipment list has been approved in respect of the operator of an aircraft pursuant to subsection 605.07(3), no person shall conduct a take-off in the aircraft with equipment that is not serviceable or that has been removed unless

(a) the aircraft is operated in accordance with any conditions or limitations specified in the minimum equipment list; and

(b) a copy of the minimum equipment list is carried on board.

(2) Where the conditions or limitations specified in a minimum equipment list are in conflict with the requirements of an airworthiness directive, the airworthiness directive prevails.

Unserviceable and Removed Equipment — Aircraft without a Minimum Equipment List

605.10 (1) Where a minimum equipment list has not been approved in respect of the operator of an aircraft, no person shall conduct a take-off in the aircraft with equipment that is not serviceable or that has been removed, where that equipment is required by

(a) the standards of airworthiness that apply to day or night VFR or IFR flight, as applicable;

(b) any equipment list published by the aircraft manufacturer respecting aircraft equipment that is required for the intended flight;

(c) an air operator certificate, a special authorization issued under subsection 604.05(2), a special flight operations certificate or a flight training unit operating certificate;

(d) an airworthiness directive; or

(e) these Regulations.

(2) Where a minimum equipment list has not been approved in respect of the operator of an aircraft and the aircraft has equipment, other than the equipment required by subsection (1), that is not serviceable or that has been removed, no person shall conduct a take-off in the aircraft unless

(a) where the unserviceable equipment is not removed from the aircraft, it is isolated or secured so as not to constitute a hazard to any other aircraft system or to any person on board the aircraft;

(b) the appropriate placards are installed as required by the Aircraft Equipment and Maintenance Standards; and

(c) an entry recording the actions referred to in paragraphs (a) and (b) is made in the journey log, as applicable.

ll airplanes are subjected to vertical gusts in level flight. These can be caused by thermals, mountain waves, and other similar atmospheric phenomena. As the airplane penetrates a rising (or sinking) column of air this momentarily changes the angle-of-attack. This either increases (rising column) or decreases (sinking column) the lift of the wing, causing the familiar “bumpiness” to be detected by the occupants as well as the airframe. This is the gust loading.

Magnetic Dip

Magnetic dip creates the most substantial errors in a compass. As you get closer to the North or South Pole, magnetic flux lines point downwards towards the poles, and your compass magnets dip towards the low side of a turn. When magnetic dip is pronounced, it’s difficult to get actual readings. This error isn’t much of a problem near the equator, where your compass points more or less horizontally and magnetic dip isn’t a concern.

Acceleration And Deceleration Error

Another major problem with magnetic compasses in airplanes is acceleration error. In the Northern Hemisphere, as you accelerate, your compass will show a turn to the North. And as you decelerate, your compass will show a turn to the South. When the speed stabilizes, the compass returns to normal. This error is greatest on East or West headings.

Use the acronym ANDS: “Accelerate-North, Decelerate-South.”

Turning Errors

During a turn from a Northerly heading, the compass briefly indicates a turn in the opposite direction. As for aircraft turning from a Southerly heading, the compass indicates a turn in the correct direction, but at a faster rate than is actually being turned.

Use the acronym NOSE: “North-Opposite, South-Exaggerated.”

PITOT TUBE BLOCKAGE

A pitot tube blockage can be caused by dirt, moisture, ice or even bugs. And, of course, aborted takeoffs after a failure to note “airspeed alive” on the takeoff roll, only to later find the pitot-tube cover still on, almost mockingly. Assuming a proper preflight inspection, ensuring the pitot tube is free and clear, obstructions can still unfortunately occur during flight. There are a few possible scenarios.

Blocked pitot tube with unblocked drain hole: This would result in the airspeed indicator reading zero. Because the pitot tube would not be able to sense any airflow, and the drain hole would let any residual air out, there would be no pressure differential for the airspeed indicator to measure. 

Blocked pitot tube with blocked drain hole: With trapped dynamic pressure, the airspeed will indicate whatever speed was showing when the blockages occurred. If the aircraft’s static port remains unblocked, pressure will increase as the aircraft descends and decrease as the aircraft climbs.

If static pressure decreases during a climb, the trapped ambient pressure with allow the diaphragm to expand, showing an increase in airspeed. Conversely, descending into denser air will force the diaphragm to close, showing a decrease in airspeed. In short, the airspeed will act in a manner similar to an altimeter. 

STATIC PORT BLOCKAGE

Blockages of the static port will affect all pitot/static instruments. 

Airspeed Indicator: If the static port is blocked but the pitot tube remains clear, the ASI will function but not with accuracy. If speed remains constant, and the aircraft climbs or descends, the static pressure will result in changes to your airspeed indication. It’s the same principle as a blocked pitot tube but reversed.

A climb will result in a decrease in atmospheric pressure entering the pitot tube, which will result in the ASI indicating decreasing airspeed, causing the ASI to act as a “reverse altimeter.” As long as the pitot tube is not blocked, changes in airspeed will reflect on the ASI, but not accurately.

Vertical Speed Indicator: With no changes to static air, there can be no differential pressure for the VSI to work with. With no differential pressure, the VSI will be stuck at zero, and you’ll marvel at how well you’re maintaining altitude.

Altimeter: The altimeter will freeze at whatever altitude was indicated when the static port was blocked. 

Using a CX3 ‘Airspeed’ function:

Using the E6B: