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9. Visual Flight Rules
9.1 Visual Flight Rules
9.1.2 Basic Radar Service for VFR traffic
9.1.3 Visual Meteorological Conditions
9.1.4 VFR Waypoints
9.1.5. Reporting Points
9.1.6. ASRC and VRC Sector Files
9.1.7 ATC VFR Instructions and Phraseology
9.1.8 Special Visual Flight Rulest
9.1.9 Composite Flight Plans
9.1.11 Further Reading
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9.1 Visual Flight Rules [C]
9.1 VFR – Visual Flight Rules
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As both navigation and phraseology is different than
when dealing with IFR pilots we hope you will find this guide interesting.
The last few years have seen an ever increasing
number of VFR scenery add-on packages and VFR flights are becoming more
popular. As a controller you will sooner or later have one or more VFR aircraft
in your area.
VFR contrary to popular belief does not mean a pilot
can take of from where ever he wants and criss cross a FIR to a destination
aerodrome.
Pilots flying under VFR assume responsibility for
their separation from all other aircraft and are not assigned routes or
altitudes by ATC. They fly on their own using a "see and be seen"
separation criteria. In busier controlled airspace, VFR aircraft are required
to have a transponder this amplifies the radar signal (as well broadcasting
altitude level and a transponder code), and is used to allow controllers to
warn IFR aircraft of any potential conflict. Governing agencies establish
strict VFR "weather minima" for visibility, distance from clouds, and
altitude to ensure that VFR pilots can be seen from a far enough distance.
In airspace ‘C’
ATC separates all aircrafts from each other (including VFR from VFR). ATC can
assign VFR routings or altitudes (minimum or maximum or both) to aircrafts in
airspace C and D
Whilst the VFR pilot does not “need” to rely on radar
for navigation or separation the fact is that the VFR aircraft in VATSIM is
tagged on radar at all times. A pilot following a Visual Flight still has to
adhere to a number of rules, follow specific VFR routes and report at specific
VFR reporting points.

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9.1.2. Basic Radar Service to VFR Traffic [C]
VFR pilots can
request, and ATC can elect to provide "VFR Advisory Services," if the
controllers' workload permits. This is also referred to as "Flight
following." Under this environment, the controllers will radar identify
the VFR aircraft and provide traffic information and weather advisory services
for the VFR pilot. Controllers do not provide any instructions concerning
direction of flight, altitude, or speed to the VFR pilot receiving advisory
services, and they do not provide separation services. This is an optional
service and may be discontinued by ATC or the pilot at any time. Other optional
service provided can be:
· Safety alerts
· Traffic
advisories
· Limited radar
vectoring, when requested by the pilot and ATC workload is low.
·
Sequencing at
locations where procedures have been established for this purpose and/or when
covered by a letter of agreement
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9.1.3 Visual Meteorological Conditions [C]
Needless to mention that the weather needs to meet
minimum VMC at all times to allow a VFR flight from taking place.
No person may operate an aircraft under basic VFR
when the flight visibility is less, or at a distance from clouds that is less, than
that prescribed for the corresponding altitude and class of airspace. if they
are not met then the flight must be flown under IFR
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Class B
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Class C, D, E
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Visibility
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At or
above FL100: 8 km
Below FL100: 5 km
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At or
above FL100: 8 km
Below FL100: 5 km
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Clouds
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Clear of
clouds
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Horizontal
distance minimum 1500m
Vertical distance minimum 300m (1000ft)
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Class F & G
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Above
3000ft MSL or 1000ft AGL whichever is higher
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At or
below 3000ft MSL or 1000ft AGL whichever is higher
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Visibility
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5 km
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3 km
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Clouds
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Horizontal
distance minimum: 1500m
Vertical distance minimum: 300m
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Clear of
clouds and ground in sight
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9.1.4. VFR Waypoints [C]
In real life operations VFR Waypoints exist, these ease navigation for
VFR pilots, using GPS systems for additional information to
that contained in their VFR charts. The primary reason they were introduced was
to enhance navigation when aircraft operate around congested airspace requiring
route restrictions or mandatory reporting points
VFR Waypoints are
assigned a discrete five-letter designator, which will be added to navigation
databases. The waypoints will all begin with the letters "VP" and
then have an additional three letters. The "VP" letters will provide
immediate recognition that the waypoint is for VFR purposes only.
VFR Waypoints
will also be used in conjunction with Visual Reporting Points. These points are
used by air traffic control (ATC) for position reporting purposes. These VFR
Waypoints will also be assigned a five-letter identifier. However, in
communications with ATC, the reporting point will still be referred to by the
full name and VFR Waypoints should be used as a tool to supplement current
navigation procedures. Pilots are strongly encouraged to rely on aeronautical
charts published specifically for visual navigation. If operating in a terminal
area, pilots should take advantage of the charts available for that area.
Pilots must use
the waypoints only when operating under VFR conditions. Anytime cloud clearance
or flight visibility diminishes below minimums, VFR flight should be terminated
immediately.
VFR Waypoints
should not be used as a sole or primary means of visual navigation. Use of
these waypoints, as one of many supplemental sources to navigation will
increase proper situational awareness.
The five-letter
identifier shall not be used in communications with ATC facilities. ATC will
not be required to be familiar with VFR Waypoint's positions or identifiers.
However, in communications with ATC, those waypoints used in conjunction with
VFR reporting points shall be referred to by the Visual Reporting Point name.
To explain the concept we use as an example the VFR
charts for EHBK (Maastricht Airport) in The Netherlands.

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9.1.5. Reporting Points [C]

To
avoid VFR traffic from flying criss-cross within a Control Zone which is also
used for IFR traffic and to enable ATC to mix and match these various flights
into and out from an aerodrome a VFR pilot has to follow standard VFR Arriving
and Departing Routes which begin, end or are intersected by Reporting Points.
Usually
these Reporting Points are distinctive natural or man-made landmarks, or
buildings. The VFR Arrival and Departure Routes usually follow a road or a
river. All aircraft flying under VFR conditions have to follow these routes
with the exception of Police and Search and Rescue Helicopters.
The reporting points
can be either compulsory reporting points or on request reporting points. A
pilot has to report over the compulsory reporting point at all times except if
ATC has issued an instruction invalidating this requirement. A pilot does not
need to report over the on request reporting point, except if ATC has
instructed to the contrary.
As you can see on the charts bellow the Compulsory
Reporting Points are shown as a Solid Triangle whilst the on request
reporting points are shown as an Non-filled-in Triangle, for example ROMEO is a
Compulsory Reporting Point whilst HOTEL is an on request reporting point.
As you can see on the chart for Maastricht there are 3 Compulsory Reporting Points, BRAVO, MIKE
and UNIFORM. Each of these points also designates the beginning or the end of
the VFR departure or arrival routes.
The VFR routes are useable for VFR traffic regardless
if arriving or departing and regardless of which runway is in use. If you look
at the BRAVO route you will see that a pilot would have to report over BRAVO
and proceed to the next compulsory reporting point which is GOLF via a non
compulsory reporting point called SIERRA, or vice versa. This route clearly
follows a river, in this case the Juliana Canal.
GOLF and ROMEO are the two exit or entry points into
the Traffic Circuit which can only be accessed at the discretion of ATC. In
practice if ATC is unable to provide a direct entry into the pattern then the
VFR traffic would have been asked to circle at one of the four visual holding
points, which as you can see are next to HOTEL, INDIA PAPA and SIERRA

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9.1.6 ASRC and VRC Sector Files[S+]
The VFR routes and reporting points can either be
added to the regular sector file as part of the SID/STAR section and Fixes
section or a stand alone dedicated VFR sector file can be created.

9.1.7. ATC VFR instructions and phraseology
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9.1.7. ATC VFR instructions and phraseology [C]

A VFR pilot usually calls
Ground or Tower directly, in real life they should call APRON or DELIVERY for
their start up approval, assuming the pilot has done his pre-flight check and
has started his engine(s), let us follow a flight from Start up to Engine shut.
Bear in mind that VFR traffic does not have to listen in on ATIS, therefore the
initial taxi clearance shall include the QNH.
As we are using the chart
for Maastricht as the example, let us assume that our VFR pilot is PH-2GY
a PA31 and that all ATC positions belong to Maastricht,
Pilot: Maastricht Ground, PH-2GY, good afternoon
GND: PH-2GY Maastricht Ground, good afternoon
Pilot: PH-2GY, PA31, General Aviation Apron VFR to Rotterdam via MIKE, request taxi
GND: PH-2GY, taxi to holding position runway 21 via, W
and W1, QNH 1017
Pilot: PH-2GY, taxiing to runway 03 via W and W1, QNH
1017
The
Pilot in the above example clearly stated his intention to fly VFR to Rotterdam via MIKE. The pilot could also have stated VFR to Rotterdam, or VFR via MIKE all three are possible, but stating
the destination as well as the VFR departure route is the most complete manner.
Pilot: PH-2GY, ready for departure
GND: PH-2GY, contact Tower on 135.450
Pilot: PH-2GY, contacting Tower on 135.450
Pilot: Maastricht Tower, PH-2GY, at W1,
ready for departure
TWR: PH-2GY, Maastricht Tower, line-up runway 21
Pilot: PH-2GY, lining up runway 21
TWR: PH-2GY, leave control zone via GOLF
right turn approved, wind 175 degrees 11 knots, cleared for takeoff runway 21
Pilot: PH-2GY, leaving control zone via GOLF, right
turn approved, cleared for takeoff runway 21
The clearance tells the
pilot that he can take off, enter the right hand traffic pattern and leave the
control zone over GOLF as Compulsory Reporting Point from where he would
continue following the MIKE departure route.
Pilot: PH-2GY position GOLF
at 1500 feet for 2500 feet
TWR: PH-2GY roger, continue
Pilot: PH-2GY, position MIKE, at 2500 feet
TWR: PH-2GY approved to leave the frequency, bye bye
Pilot: PH-2GY, Good bye
At this point the pilot would leave
the frequency but could ask for VFR advisory service in which case the pilot
would normally be asked to switch frequency to a radar controller. Or the pilot
would continue on his own route to Rotterdam.
Half
way to Rotterdam however the pilot decides to turn around and return
to Maastricht. The aircraft is approaching the aerodrome from the
South and the pilot will need to report his intentions before arriving over the
compulsory reporting point UNIFORM.
Pilot:
Maastricht Tower, PH-2GY
TWR: PH-2GY, Maastricht Tower go ahead
Pilot: PH-2GY, PA13, VFR, 10 miles South of UNIFORM,
2500 ft, for landing
TWR: PH-2GY, enter control zone via UNIFORM, runway
03, QNH 1009
Pilot: PH-2GY, entering control zone via UNIFORM,
runway 03, QNH 1009
The pilot now knows he can enter the Control
Zone and approach the aerodrome via the UNIFORM arrival route, and will need to
report over ROMEO next. However further ATC clearance is required before the
pilot can enter the actual traffic circuit after ROMEO.
Pilot: PH-2GY, position
UNIFORM, 2500 feet
TWR: PH-2GY, roger
Pilot: PH-2GY, position ROMEO, 2500 feet
TWR: PH-2GY, join traffic circuit runway 3
Pilot: PH-2GY, joining traffic circuit runway 3
TWR: PH-2GY, wind 050 degrees 8 knots, cleared to land
runway 3
Pilot: PH-2GY, cleared to land runway 3
As
you see the Pilot needs the clearance by ATC before entering the traffic
pattern after ROMEO. In the event no such clearance is received then the pilot
should enter the circling pattern as indicated on the charts or as instructed
to by ATC.
TWR: PH-2GY, hold over HOTEL
TWR: PH-2GY, hold south of
the field
For the rest the approach and landing
clearances are similar to those used when dealing with IFR.
As
TWR controller in VATSIM you most likely will have a mix of VFR and IFR traffic
at the same time, most VFR traffic will be slow and most IFR traffic will be
heavy or fast, below find a number of traffic situations and the required
action needed to make the flow and sequencing of VFR and IFR be as smooth as possible.
The IFR traffic is being vectored and sequenced by Approach and as Tower your
influence in this process is non existent. If you have VFR traffic under your
control you will need to slot them into the landing pattern the one and only
influence you as TOWER has over Approach is to request that the IFR inbound
traffic be separated more than usual to allow the VFR plane to be slotted in
between.
Here
are a few examples; again we will use PH-2GY the PA13 for approach to rwy 03 in Maastricht together with KL123 a B737 on his way in on the ILS for rwy 03.
Orbit
The
most common and easiest way to increase separation is to issue an Orbit or 360
degree instruction. This automatically increases the separation between the
traffic.
TWR: PH-2GY
make a right three sixty
Note the differences bellow:
TWR PH-2GY Orbit over POINT
This results in a continuous circling until ATC instructs to the
contrary.
TWR PH-2GY Fly 360° over POINT
This results in one complete 360 degree circle after which the pilot
will resume his original course.
TWR PH-2GY Fly one orbit over POINT
This results in one complete 360 degree circle after which the pilot
will resume his original course.
TWR PH-2GY Fly 360s over POINT until further instructions
This
results in a continuous circling until ATC instructs to the contrary.
Once the VFR pilot has made a full circle he
would normally continue his downwind leg, and
by this time the IFR traffic will either be on short final or will already have
landed. Hence the VFR traffic can be cleared for the approach
The
thing to bear in mind is the Wake Turbulence factor between aircraft categories
as explained earlier. The wake turbulence warning should be given when the VFR
traffic is still on his downwind leg as the pilot of the VFR aircraft can then
use best judgment in deciding to increase or decrease this leg before turning
in to final.
TWR: PH-2GY, caution wake
turbulence from just landed Boeing 737
TWR: PH-2GY, caution wake turbulence from Boeing 737
on short final
In the event one full circle should not suffice
to ensure sufficient separation between the various aircraft in the pattern or
on final ATC can instruct the VFR traffic to continue orbiting until cleared
for the approach.
TWR: PH-2GY, orbit left
TWR: PH-2GY, continue approach
Short
Approach
If the IFR traffic is further than 8 miles distant
from the field then ATC can ask a VFR pilot if he can follow a short approach.
This in essence means that the VFR aircraft will shorten his final approach to
less than 1nm and land before the IFR traffic.
TWR: PH-2GY, can you accept a short
approach?
Pilot: PH-2GY, affirm
TWR: PH-2GY, make a short approach, wind 090 at 5
knots, cleared to land rwy 03
ATC would then provide the pilot of the IFR
flight with the required traffic information
Extended
Approach
In
the event that a pilot cannot execute a short final approach or if there is
other traffic on short final, ATC can instruct the VFR traffic to extend the
downwind leg thereby ensuring that the traffic is sequenced and sufficient
separation exist between the different approaching aircraft. Remember as ATC,
if you are sequencing a light propeller type aircraft in after a medium or
heavy jet that wake turbulence will most probably be a factor.
TWR: PH-2GY; fly extended right downwind, standby for base.
TWR: PH-2GY; continue approach, caution wake
turbulence from preceding 737.
Pilot in
Command
Another
manner to deal with the situation is to pass the entire process to the pilots.
In essence ATC advises the VFR pilot to follow and maintain visual separation
with the IFR traffic
TWR: PH-2GY, Number two, follow Boeing 737 on 5 miles final,
caution wake turbulence
Bear in mind that it is good
practice to advise the IFR flight crew of the existence of the VFR traffic in
the area.
9.1.8. Special Visual Flight Rules
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TWR: KL123, PA13 on downwind runway 03 at your 3 o’clock,
report traffic in sight
The
pilot in turn has the responsibility to inform ATC of having the
preceding traffic in sight and indeed also report if he does not have
traffic in sight, in which case the responsibility for separation
returns to ATC.
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9.1.8 Special Visual Flight Rules [C]

We have mentioned these before and whilst these are no relevant to VATSIM
on line flying we thought it would be interesting to briefly explain what this
is.
Special visual flight rules (SVFR)
are a set of aviation regulations under which a pilot may operate an aircraft.
A pilot can request an SVFR clearance from air traffic control to operate
within a area of controlled airspace when the local weather is less than the
minimums required for flight under visual flight rules. Like flight under
instrument flight rules, air traffic control will provide separation from other
aircraft; unlike IFR flight, the pilot does not require an instrument rating
(for daytime SVFR flight) and the aircraft must remain clear of clouds and must
maintain at least one mile of flight visibility. The pilot continues to be
responsible for obstacle and terrain clearance.
SVFR clearances
only apply within CTR’s once the aircraft leaves the CTR the flight reverts to
visual flight rules and weather requirements.
An example of a
use for special visual flight rules would be ground fog or mist obscuring the
ground visibility at a controlled airport while visual meteorological
conditions exist above, or at to fly visually at night in control zones in
countries that do not allow VFR night flights.
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9.1.9 Composite Flight Plans [S]

The type of
flight plan which a pilot intends to file and fly forms part of the flight plan
in VATSIM you can identify these by looking at the Target or by looking at the
flight plan. VATSIM only allows for I, V and S. in real life there are two
other types the so called composites being Y and Z as outlined bellow.
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I
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IFR Instrument Flight
Rules
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V
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VFR Visual Flight
Rules
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Y
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Composite IFR/VFR
aircraft will commence flight under IFR and change to VFR during the flight
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Z
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Composite VFR/IFR
aircraft will commence flight under VFR and change to IFR during the flight.
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S
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