Block 4 Exam Review Flashcards
Glossary > Windshear
A change in wind speed and/or wind direction in a short distance. It can exist in a horizontal or vertical direction and occasionally in both.
Glossary > Minimum Obstacle Clearance Altitude (MOCA)
The altitude above sea level between specified fixes on airways or air routes that meets the IFR obstacle clearance requirements for the route segment in question.
This altitude is published on aeronautical charts.
Glossary > Minimum Enroute Altitude (MEA)
The altitude above sea level between specified fixes on airways or air routes that assures acceptable navigational signal coverage and that meets the IFR obstacle clearance requirements.
This altitude is published on aeronautical charts.
TC AIM > Area Minimum Altitude (AMA)
The lowest altitude to be used under Instrument Meteorological Conditions (IMC) that will provide a minimum vertical clearance of 1000 ft. or, in a designated mountainous region, 2000 ft., rounded up to the next 100-ft. increment, under conditions of standard temperature and pressure, above all obstacles located in the area specified.
Similar concept to MOCA but not restricted to an airway or route
Glossary > Minimum Sector Altitude (MSA)
The lowest altitude that will provide a minimum clearance of 1000 ft under conditions of standard temperature and pressure above all objects located in an area contained within a sector of a circle with a 25 NM radius centred on a radio aid to navigation or a specified point.
US: minimum safe altitude
Glossary > Minimum Vectoring Altitude (MVA)
The lowest altitude for vectoring aircraft by ATC that meets obstacle clearance and radio coverage requirements in the airspace specified.
Safe altitude 100 nautical miles
An altitude, usually found on CAP charts, that is flight checked and approved for use within 100 miles of the geographical centre of the aerodrome as depicted on the CAP chart and meets obstruction clearance requirements.
Transition Altitude (on arrival)
In most cases for IFR, it is an altitude specifically shown for an aircraft that is changing (“transitioning”) from enroute to approach.
Speed Assignments > Airspeed Limitations
Do not approve a speed over 250 knots IAS below 10000 feet above sea level, but acknowledge a pilot who informs you of a requirement to operate above the CARs-regulated speed limitations for minimum safe speed requirements.
If a pilot reports or operates at a speed over 250 knots below 10000 feet above sea level and does not state that it is for minimum safe speed, inform the operations duty manager.
TC AIM RAC 2.5.2 Aircraft Speed Limit Order
According to CAR 602.32, no person shall operate an aircraft in Canada;
(a) below 10 000 ft ASL at more than 250 KIAS; or
(b) below 3 000 ft AGL within 10 NM of a controlled airport and at more than 200 KIAS, unless authorized to do so in an air traffic control clearance.
Exceptions
(a) A person may operate an aircraft at an indicated airspeed greater than the airspeeds referred to in (a) and (b) above where the aircraft is being operated in accordance with a special flight operations certificate – special aviation event issued under CAR 603.
(b) If the minimum safe speed, given the aircraft configuration, is greater than the speed referred to in (a) or (b) above, the aircraft shall be operated at the minimum safe speed.
Table: Speed Adjustment Guidelines > Minimum Assignable Speeds
- 20 miles or more distance to destination
> 10000 ASL and above > 250 IAS
> Below 10000 ASL > 210 IAS - Less than 20 miles distance to destination
> Turbojet > 150 IAS (Use only when required for spacing on final approach) / 160 IAS (Preferred when assigning a speed to cross the final approach fix)
> Propeller > 120 IAS
Invalid Altitude Readouts > When is an altitude readout considered invalid and what do you do when it is (full procedures)
Take action as indicated in Invalid Altitude Readouts when either of the following applies:
* An altitude readout is invalid.
* You observe a previously validated altitude readout to be invalid for four or more successive readout updates.
- Altitude readout is invalid
> ensure the pilot has the correct altimeter setting
> request another altitude verification
“(altimeter name) altimeter (setting). Check altimeter setting and confirm (altitude)” - Aircraft’s altimeter setting is correct and the altitude readout remains invalid
> instruct the pilot to reset the transponder or ADS-B
> if, after resetting, the readout remains invalid, instruct the pilot to turn off Mode C or ADS-B altitude transmission and give the reason
“Stop squawk mode charlie. Altitude readout differs by (number) feet.”
“Stop ADS-B altitude transmission. Altitude readout differs by (number) feet” - The aircraft’s Mode C cannot be turned off without turning off the transponder
> do not use the altitude readout as an indication of the aircraft’s present altitude - The aircraft’s ADS-B altitude cannot be turned off without turning off the ADS-B transponder
> Do not use the altitude readout as an indication of the aircraft’s present altitude
> You may consider the vertical distance between the pilot-verified altitude and the ADS-B invalid reported altitude as a block altitude
> If a TCAS alert is likely to occur, issue traffic information and a cautionary indicating the invalid information to other aircraft in proximity
> You may instruct the pilot to turn off ADS-B or their transponder and then apply an appropriate non-surveillance separation standard
> Follow the procedures in ADS-B Unserviceable or Malfunctioning
Invalidated Altitude Readouts > When can you use invalid altitude readouts?
Do not use invalidated altitude readouts to determine an aircraft’s altitude.
You may use invalidated altitude readouts to do any of the following:
* Observe whether an aircraft is in level flight, climbing, or descending
* Observe rates of climb or descent
* Provide traffic information.
Validated Altitude Readouts > Consider an aircraft to…
You may use validated altitude readouts to determine aircraft altitudes as indicated in the following table. Consider an aircraft to…
* be maintaining altitude when its altitude readout is within 200 ft of the assigned altitude
* have reach an altitude when its altitude readout has been within 200 ft of the assigned altitude for 4 consecutive readout updates
* have vacated an altitude when its altitude readout has changed by 300 ft or more, in the appropriate direction, from the value that prevailed while the aircraft was in level flight
* have passed an altitude when its altitude readout has changed by 300 ft or more in the appropriate direction
Class A Airspace
- Controlled high level airspace from FL180/FL230/FL270 to FL600
- IFR only
Class B Airspace
- Controlled low level airspace above 12 500 ft or from the MEA, whichever is higher to 17999 ft
- TCAs and associated primary CZs may be class B
- IFR or CVFR
Class C Airspace
- CZ around a large airport and associated TCAs and extensions
- Usually a 10 nm radius
- IFR and VFR, clearance required
Class D Airspace
- CZ around smaller airports
- 5 nm or 3 nm radius and 3000 AAE height
- IFR clearance required, VFR dialogue required
Class E Airspace
- Everything else - need for controlled airspace exists but does not meet the requirements of other classes
- Low level airways/air routes, airports without towers, airspace above FL600
- IFR clearance required, VFR does not
Class F Airspace
- Restricted, advisory, military or danger areas
- Can be controlled or uncontrolled
- CYA - A/F/H/M/P/S/T
Class G Airspace
- Uncontrolled airspace
Vectoring > Vectoring into Class G Airspace
You may vector an aircraft into Class G airspace if you inform the pilot and obtain the pilot’s approval.
The rule is that every one hundredth of an inch of mercury is equivalent to 10 feet.
The difference between 29.92 and 29.93 is 10 feet.
The difference between 29.92 and 29.82 is 100 feet.
The difference between 29.92 and 28.92 is 1000 feet.
Remember: high to low, look out below; low to high, clear blue sky
Weather Information > Altimeter Setting Information
Issue the altimeter setting as follows:
* Identify the setting by the name of the station to which it applies, unless:
◦ The setting applies to the station at which the unit is located.
◦ There is no possibility of misunderstanding.
For example, Toronto ACC issuing an altimeter setting for Peterborough: “Peterborough altimeter two-niner-seven-two.”
For example, Edmonton ACC issuing an altimeter setting for Red Deer and Edmonton: “Red Deer altimeter two-niner-six-six; Edmonton altimeter two-niner-six-three”
* If the setting is 28.99 or lower, or 31.00 or higher, state the setting twice
* If the setting is higher than 31.00, issue the actual altimeter setting and confirm that the pilot has set the aircraft altimeter to 31.00.
* If the setting is obtained from a weather report that is one hour old or more, include the time of the report.
* If the setting changes by ± 0.02 inches or more, issue a revised altimeter setting.
* If a pilot asks which type of setting is provided, identify the setting as QNH (height above sea level). [4]
If no local or remote altimeter is available for a location, inform the pilot when issuing landing information.
4 An altimeter on a QNH setting displays the height above sea level. In Canada, the height above aerodrome elevation or relevant runway threshold (QFE) is not available.
Lowest Usable Flight Level
Do not assign any flight level lower than the lowest usable flight level indicated in the following table.
Altimeter Setting > Lowest Usable Flight Level
29.92 and higher > FL180
29.91 - 28.92 > FL190
28.91 - 27.92 > FL200
27.91 and lower > FL210
If a change in altimeter setting requires an increase or permits a decrease in the lowest usable flight level, coordinate with adjacent sectors or units as required.
Maintaining Vertical Separation > Assigning Altitudes
You may assign an altitude only after another aircraft previously at that altitude, or climbing or descending through that altitude, has reported or is observed doing one of the following:
* Vacating or passing the altitude you want to assign
* Vacating or passing an altitude separated by the appropriate minimum from the altitude you want to assign, and one of the following applies:
◦ Severe turbulence exists.
◦ The aircraft previously at the altitude you want to assign has been issued a cruise climb.
STAR > Managing Aircraft Operating on a STAR
Vectoring an Aircraft Off a STAR the Re-establishing it on the Same STAR
If you vector an aircraft off a STAR, instruct the pilot to rejoin the STAR using one of the following:
* Direct to a waypoint
* Intercept between two waypoints
Rerouting an Aircraft to Another STAR or STAR Transition
If necessary, issue appropriate joining instructions to reroute the aircraft to another STAR or STAR transition, and instruct the pilot to rejoin the STAR.
TC AIM RAC 9.2.3.5 > Altitude Restrictions
Altitude restrictions may be included in the STAR. Although an aircraft is expected to follow the charted lateral track of the cleared STAR without further ATC clearance, as per the flight-planned/cleared route, such is not the case with the STAR vertical profile; ATC has to issue descent clearance, and when a lower altitude is issued, pilots shall descend on the STAR profile to the ATC-assigned altitude. Unless specially cancelled by ATC, all charted restrictions above the assigned altitude on the STAR remain mandatory.
Boeing 757 Exception
A Boeing 757 is a medium aircraft EXCEPT when it is a leading aircraft, in this situation it is considered a heavy for wake turbulence purposes.
Arrivals > STAR
Consider an aircraft to have been cleared for the STAR if the STAR is included in the routing portion of the flight plan.
Clearance for the STAR allows the aircraft to follow the lateral track only, descent clearance must be received from ATC. Clear an aircraft flying a STAR for descent in sufficient time to meet any published altitude restriction. Pilots are required to comply with all published altitude and speed restrictions at or above the cleared altitude unless specifically cancelled by ATC.
Types of Ice
Rime - small super-cooled water droplets, brittle, rough, opaque
Clear - large super-cooled water droplets, hard, glossy, and translucent. Hardest to remove.
Mixed - hard, rough congolomerate of both types above
Glossary > Wake Turbulence
Turbulent air behind an aircraft caused by any of the following:
* Wing-tip vortices
* Rotor-tip vortices
* Jet-engine thrust stream or jet blast
* Rotor downwash
* Prop wash
Wake Turbulence Separation Table
(First aircraft > Second aircraft)
Super > Super = 4 miles
Super > Heavy = 6 miles
Super > Medium = 7 miles
Super > Light = 8 miles
Heavy > Super = 4 miles
Heavy > Heavy = 4 miles
Heavy > Medium = 5 miles
Heavy > Light = 6 miles
Medium > Light = 4 miles
Communication Transfer > Mandatory Frequency Area
When an aircraft is approaching an MF area, instruct the pilot to change to the MF before reaching the area. If the pilot needs to leave your frequency to make required Mandatory Frequency Area Reports, advise the pilot to report leaving and returning to ATC frequency.
“(a/c ID) advise prior to leaving this frequency to make the mandatory frequency reports”
“(a/c ID) advise returning to this frequency”
Terminav > RSC/CRFI NOTAM
A NOTAM disseminated to alert pilots to natural winter surface contaminants such as snow, slush, and ice conditions that could affect aircraft braking and other operational performance. Such NOTAMs are considered special series NOTAMs that, because of their short life and significant volume during the winter season, require non-standard handling.
COMMENT: Note 1: This term is derived from the words “Runway Surface Condition/Canadian Runway Friction Index NOTAM.” Note 2: This NOTAM may also be issued by a military ATC unit as an RSC/JBI NOTAM.
Terminav > RSC Report
Section of the Aircraft Movement Surface Condition Report (AMSCR) which provides runway surface information using a verbal description of the runway condition.
RSC and CRFI
Issue the current RSC and CRFI report for the intended runway using a four-digit time expression format[1].
It is not required to relay RSC information to the pilot when the runway is cleared to the full width and it is 100% dry.
It is not required to relay CRFI information to the pilot when:
* CRFI by full runway length is reported as NR.
* All thirds of CRFI by thirds are reported as NR.
Glossary > CRFI
The average of the runway friction as measured by a mechanical or electronic decelerometer and reported through the Aircraft Movement Surface Condition Report (AMSCR).
Contaminated Runway
A runway is contaminated when a significant portion of the runway surface area (whether in isolated areas or not) within the length and width being used is covered by one or more of the following substances:
* Compacted snow
* Dry snow
* Frost
* Ice
* Slush
* Standing water
* Wet ice
* Wet snow
Identification Doubtful or Lost
If identification becomes doubtful or is lost, immediately do either of the following: * Identify or re-identify the aircraft using the same technique more than once or use more than one of the techniques provided in Identification Methods. * Terminate ATS surveillance service and apply procedural separation.
Identification may be doubtful due to:
* The position or movement of other aircraft
* The observation of more than one aircraft responding to an identification instruction
* Temporary loss of the PPS
* Coasting of the PPS
* Merging of the PPS
* Ambiguous PPS
* Display clutter
* Other circumstances
When identifcation is lost, inform the pilot.
“Identification lost” / “Surveillance service terminated”
Traffic Information > Who do we provide traffic information to?
Provide traffic information to pilots of aircraft in Class C and Class D airspace.
Provide traffic information to pilots of aircraft in Class E airspace, unless workload[6], equipment limitations[7], or higher priority duties[8] prevent you from doing so.
[6] In this context, workload means traffic volume, traffic complexity, radio frequency congestion, coordination, or other control-related duties. It does not include system limitations created by on-the-job training, staffing, employee periods of relief, or other workplace constraints.
[7] Limitations can occur when communications or ATS surveillance equipment becomes degraded or unserviceable.
Provide traffic information to all concerned aircraft if any of the following apply:
- You clear an aircraft to maintain at least 1000 feet on top.
- You clear an IFR aircraft to fly in accordance with VFR.
- Multiple aircraft are holding at the same fix and are separated by the vertical separation minimum.
- A pilot requests it.
- A pilot acknowledges an avoidance instruction.
- You consider it necessary.
Traffic Information Format
When issuing traffic information to aircraft, as appropriate, include:
1. Position of aircraft
2. Direction of flight
3. Type of aircraft or relative speed
4. Altitude of aircraft
5. Reporting point and time
6. Other information
Ex/ ALFA BRAVO CHARLIE, TRAFFIC TWO-SEVEN MILES WEST OF DUSTY V-O-R, EASTBOUND CARAVAN NINER THOUSAND ESTIMATED DUSTY V-O-R AT ONE-TWO-FIVE-ZERO.
Control Estimates
Base control decisions on ATC estimates and aircraft performance. Verify the estimate and aircraft performance using position reports over fixes, or as determined by radio aids, ATS surveillance, RNAV, or visual means that accurately define the position of the aircraft.
* CAATS-generated times are considered ATC estimates. Although estimates are system-generated, controllers are not relieved of the responsibility for ensuring estimates are accurate.
* This includes position reports derived from ADS-C and CPDLC.
Use aircraft estimates to verify ATC estimates. If a discrepancy exists between an aircraft estimate and an ATC estimate for the same reporting point, and separation could be affected:
1. Check the accuracy of the ATC estimate.
2. If a discrepancy remains, request the pilot to check the aircraft estimate.
3. If a discrepancy still exists, take appropriate action to ensure that separation is not compromised.
Use worst case scenario
- The requirement to use pilot estimates to validate ATC estimates varies with traffic density, type of operations (arrival, departure, enroute, ATS surveillance), and whether a wind component is known and valid. Where limited opportunities exist for position reports, you should obtain pilot estimates to validate (for example, an IFR flight, where the arrival fix is the only position after departure).
- An ADS-C-next-fix time is considered an aircraft estimate.
When separating aircraft, the estimated time may not be correct. If an expected report does not arrive and flight safety is likely to be jeopardized, obtain the report no more than 5 minutes after the estimated time over a reporting point. Otherwise, obtain the report as soon as feasible.
SOM 650 Airway Overlap
It has been determined by Airspace Planners that the overlap of protected airspace between V306/V327 discontinues 6.8 miles (or 8 DME including slant range for altitudes below 18000’ ASL) from YDD. Aircraft that report more than 6.8 miles, or 8 DME from YDD established on either airway are clear.
Altimeter Information > Altimeter Setting Region
If an enroute aircraft operating within the Altimeter Setting Region makes a position report via direct communication, issue the current altimeter setting for:
* The station over which the aircraft reports
* The next station along the route of flight
Time-Based Longitudinal Separation > Same Track Operations
For aircraft on the same track, apply time-based longitudinal separation as indicated below.
15 min > Any speed differential > No conditions
10 min > Any speed differential > Position reports are obtained at least every 40 min. See Longitudinal Sep Using Position Reports: Same Speed
5 min > Leading a/c is at least 20 kts faster > Same altitudes, position reports are obtained at least every 40 min, and one of the following applies:
* a/c have departed from adjacent locations and have reported over the same reporting point
* both are enroute a.c that have reported over the same reporting point
* enroute a/c has reported over a reporting point serving a point of departure, and is ahead of a departing a/c
3 min > Leading a/c is at least 40 kts faster > Same conditions as 5 min
Time-Based Longitudinal Separation (Excerpt)
Establish time-based longitudinal separation using one of the following methods:
* On the basis of position reports, provided that one of the following applies:
◦ Both aircraft have reported over the same reporting point.
◦ The trailing aircraft has confirmed not yet reaching the reporting point used by the leading aircraft.
Distance-Based Longitudinal Separation > Same Track Operations
If aircraft on the same track are using DME, GNSS, or both, apply distance‑based longitudinal separation as indicated below.
20 miles > Any speed differential > No conditions
10 miles > Leading aircraft is maintaining 20 knots or more faster > Same altitude, and one of the following applies:
* a/c have departed from adjacent locations and have reported over the same reporting point
* both are enrout a/c that have reported in relation to a common point
* enroute a/c has reported over a reporting point serving a point of departure, and is ahead of a departing a/c
5 miles > Leading a/c is maintaining 40 kts or more faster > Same conditions as 10 miles
Time-Based Longitudinal Separation > Crossing Track Operations
For aircraft on crossing tracks, apply time‑based longitudinal separation, calculated from the point that the tracks cross, of either: * 15 minutes
* 10 minutes, provided you obtain position reports at least every 40 minutes (Longitudinal Separation, Crossing Tracks)
Position Reports
You can obtain position reports using:
* ADS‑C
* CPDLC
* VHF/UHF
* Observed ATS surveillance position of an identified PPS
Position reports can be made with reference to:
* NAVAID fixes
* VHF NAVAID radials
* DME arcs
* Bearings from an NDB
* Waypoints from RNAV
* Full degrees of longitude or latitude from GNSS‑equipped aircraft
Distance-Based Longitudinal Separation > Crossing Track Operations
If aircraft on crossing tracks are using DME, GNSS, or both, from a common point and the tracks cross at the common point, separate the aircraft by either:
* 20 miles (Longitudinal Separation: Crossing Tracks Using DME or GNSS)
* 10 miles, if the leading aircraft is maintaining 20 knots or more faster than the following aircraft
The distance is calculated from a common point over which both a/c are cleared
Lateral Separation > Geographical Separation
When applying geographical separation, determine the appropriate fix-tolerance area for each aircraft as indicated in Fix-Tolerance Area for Geographical Separation. Consider aircraft geographically separated if the fix-tolerance area for one aircraft does not overlap either of the following:
* The fix-tolerance area for another aircraft (Geographical Separation: No Overlap of Another Fix-Tolerance Area)
* The protected airspace for another aircraft (Geographical Separation: No Overlap of Protected Airspace)
Table: Fix Tolerance for Geographical Sep
Source of Position Info > Fix-Tolerance Area
ATS Surveillance > ATS surveillance sep minimum
NAVAIDs > Values are depicted by Aeronautical Information Management, or as directed by unit management
RNAV in RNPC airspace > RNPC separation
RNAV in CMNPS airspace > CMNPS separation
Visual reference to the ground > Use caution to ensure that the aircraft’s position is accurately defined. Lateral separation
RNAV > 25 miles for RNP-10 and RNP-4 approved aircraft
Vertical Separation For Aircraft on Reciprocal Tracks (Excerpt)
In an ATS surveillance environment, discontinue vertical separation as detailed in ATS Surveillance Separation For Aircraft on Reciprocal Tracks. In a procedural environment, you may discontinue vertical separation based on one of the factors indicated in Discontinuing Vertical Separation in Procedural Airspace. In a mixed environment, the distance of an identified aircraft from the common point, as determined by an RBL or the DME estimate function, may be used in lieu of a DME or GNSS position report.
NAVAID Passage Conditions
* Both pilots have reported passing over the same ground-based NAVAID
* If at FL180 or above, the aircraft are 2 min apart (this compensates for overhead fix tolerance)
DME and/or GNSS Passage
* DME and/or GNSS reports, determined in relation to a common point, indicate that the aircraft have passed and are 5 miles apart
* The outbount aircraft, if utilizing DME, is 15 miles or more from the DME facility (if the outbound a/c from the common point is /G equipped, slant range is not a factor)
Transponder Code Numbers
A combination of the numbers 0 through 7; 8 and 9 are not used
Closing Flight Plans and Flight Itineraries > IFR Flight Plan or Flight Itinerary
When the pilot of an IFR aircraft closes[1] the IFR flight plan:[2]
* If VFR flight is not permitted due to airspace classification or weather conditions:
◦ Inform the pilot.
◦ If appropriate, pass the most recent weather sequence.
◦ Ask the pilot’s intentions.
* Acknowledge the closure and inform the pilot that alerting service is terminated.
* Inform the appropriate ACC or the agency responsible for alerting service at the destination.[3]
1 A pilot’s decision to close an IFR flight plan or itinerary is not subject to ATC approval.
2 When a pilot cancels or closes an IFR flight plan, the aircraft automatically becomes a VFR flight.
3 This may be done electronically.
Cancelling IFR
If the pilot of an IFR or CVFR aircraft cancels IFR:[1]
* If VFR flight is not permitted due to airspace classification or weather conditions:
◦ Inform the pilot.
◦ If appropriate, pass the most recent weather sequence.
◦ Ask intentions.
* Acknowledge the cancellation.
A pilot’s decision to cancel an IFR flight plan or itinerary, or change to a VFR flight plan or itinerary, is not subject to ATC approval (don not suggest or ask a pilot to cancel IFR)
* Ask whether the pilot is closing the IFR flight plan or itinerary, and respond “Roger, are you closing your flight (plan/itinerary)”
◦ Yes > Acknowledge the closure, inform the pilot that the IFR flight plan is closed and alerting service is terminated
◦ No > If the pilot intends to land at an aerodrome with an operating ATS unit, coordinate appropriately
◦ No > If the pilot intends to land at an aerodrome without an operating ATS unit, advise that an arrival report is required after landing
1 By regulation, the phrase CANCELLING IFR does not close the flight plan or itinerary.
Standard Holding Pattern
Fix > fix end (abeam) > outbound leg > outbound end > inbound leg
Recall: holding side and non-holding side
Glossary > Special VFR Flight
A visual flight authorized by an ATC unit to operate within a control zone under meteorological conditions that are below visual meteorological conditions
Visibility Minima
The minimum visibility for VFR and SVFR aircraft in a control zone is indicated in VFR and SVFR Minima for Flight in a Control Zone
Fixed wing > VFR min 3 miles > SVFR min 1 mile
Helicopter > VFR min 3 miles > SVFR min 1/2 mile
Where ground visibility is reported, tower-observed visibility is considered advisory only. When no other visibility report is available and the control tower is not in operation, SVFR operations may be allowed based on a flight visibility report.
Reported or tower-observed visibility is applicable to the control zone, whereas flight visibility is applicable only to the aircraft providing it.
Authorizing a Pilot’s Request for SVFR
Authorize SVFR within the control zone, provided:
* The pilot requests SVFR.
* The ground visibility is at or above the minimum for SVFR. You may use the tower observation of prevailing visibility where ground visibility is either not reported or the visibility reported by the AWOS is non-representative of the prevailing visibility at the airport.[1][2]
* You obtain approval from the appropriate ACC.
* You make an adequate arrangement for recall.
* You keep SVFR aircraft clear of the flight paths of IFR aircraft.
* You authorize only the number of aircraft that you can control safely and efficiently. If all aircraft remain in sight of the tower at all times, you may authorize more than one SVFR aircraft in a circuit.
* If the pilot intends to depart or transit the zone at night, the SVFR aircraft is a helicopter.
Issuing and Relaying > Delivery Limitations
The communication agency, such as the FSS, FIC, CARS, dispatcher (in emergencies), or others to which a clearance is issued is responsible for transmitting the clearance to the aircraft immediately upon receipt, unless an attempt-delivery time has been specified.
If a communication agency informs you that a clearance has not been delivered, instruct the agency to do one of the following depending on your situation:
* Continue attempting to deliver, and report if undelivered by a specified time.
* Attempt to deliver at a specified time.
* Cancel the clearance.
You will be notified if the clearance is not delivered within 3 minutes after receipt, or the specified attempt‑delivery time.
Approach Clearance Format
”[[to the] (name) airport]” > In an ATS surveillance environment, you may omit the name of the airport from an approach clearance, provided:
◦ The a/c is identified and monitored until established on final approach
◦ There is no likelihood of misunderstanding[11]
11 Misunderstanding could occur if another aircraft, on your frequency and anticipating approach clearance to a different airport, accepts the approach clearance by mistake.
Assignable Altitudes
Lesson 204 page 8
CYUN Arrivals
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