A Hong Kong-based Virtual Airline VFR Circuit Tutorial VOHK Training Team Version 2.1 Flight Simulation Use Only 9 July 2017 Copyright 2017 Oasis Hong Kong Virtual Page 1
Oasis Hong Kong Virtual (VOHK) is a Hong Kong-based Virtual Airline founded by Hong Kong flight-simmers in 2011. We are committed to providing enhanced and interactive flight simulation experience for all our flight-simmers in Hong Kong and across the globe. Purpose Written by the Training Team of Oasis Hong Kong Virtual, the purpose of this tutorial, VFR Circuit Tutorial, is to provide flightsimmers with fundamental knowledge about VFR Circuit and basic maneuverers for flying. Objective Through this tutorial, the pilot should be able to understand the following aspects of knowledge and how they interact with the flight simulator environment. Syllabus Covered VOHK IVAO VATSIM Basic Maneuverers: Take-off and Landing FS3 Rating - VFR Circuit Test 1 PP Rating P3 Rating VFR Circuit Departure and Join PP Rating P3 Rating If you have any question regarding this tutorial, please feel free to contact us via vptp@voasis.org Oasis Hong Kong Virtual Website: http://www.voasis.org Facebook: http://www.facebook.com/voasis Copyright 2017 Oasis Hong Kong Virtual Page 2
Chapter 1 - Introduction First of all, why do we have to fly circuits (or known as traffic pattern)? It is very simple, circuit is the best way of practicing your flying skills from takeoff, climb, cruise, descend, approach to landing! When you have mastered the Normal Circuit, there are more waiting for you, such as Flapless Circuit, Glide Approach, Low Level Circuit, Short Field Takeoff and Landing and Night Circuit! In real life, every pilot uses circuit to practice their skills, no matter it is a Cessna 172 or a Boeing 777-300ER. Do not worry, this manual is going to focus on Normal Circuit for a General Aviation aircraft, it is not that difficult! We all start from the basic. Chapter 2 - List of Appendix Appendix A: Reference Materials: CASA VFR Circuit Departures and Joins Chapter 3 - Circuit Legs There are 5 legs in a circuit, which are Upwind, Crosswind, Downwind, Base and Final. Assume the aircraft is taking off into pure headwind. 3.1 Upwind leg A straight flight path following the extended centerline. After takeoff the aircraft should be flying into the wind, that is why it is call the Upwind leg. 3.2 Crosswind leg It is perpendicular to the Upwind leg. Wind is now coming from the side of the aircraft. It is experiencing a pure crosswind. 3.3 Downwind leg It has a reciprocal track to the takeoff direction, which is perpendicular to the Crosswind leg and in opposition direction to the Upwind leg. Wind is coming from behind and pushing the aircraft. 3.4 Base leg It connects the Downwind and the Final leg. It is perpendicular to the Downwind leg, track is parallel to but in opposite direction to the Crosswind leg. 3.5 Final leg The aircraft is lined up with the runway, on the extended centreline, performing final approach and prepared to land on the runway. Copyright 2017 Oasis Hong Kong Virtual Page 3
Fig. 1 Circuit Leg Chapter 4 - Sides For a runway, it is divided into live side and dead side. Depending on the aerodrome procedures, one side is designated as live and another side is designated as dead. This would determine whether the circuit is a right hand circuit or a left hand circuit. If the live side is on the left hand side of the runway, it is a left hand circuit, and vice versa. For a left hand circuit, all turns should be made to the left, and vice versa. Fig. 2 Left Hand Circuit (All turns to the left) 4.1 General Rule One (1) Runway: usually a left hand circuit Parallel Runway: left hand circuit for the left runway, right hand circuit for the right runway. If there is a centre runway, it should not normally be used for circuit training. Copyright 2017 Oasis Hong Kong Virtual Page 4
Fig. 3 Left Runway, Left Hand Circuit; Right Runway, Right Hand Circuit However, this is not always accurate as there are variations between aerodromes due to constraints such as terrain considerations, noise abatement procedures, airspace requirements etc. Check the local procedures before flying. Furthermore, some aerodromes may specify different type of circuits for different runways. For example, Parafield Airport (YPPF) at Adelaide has specified the left runway for single engine aircraft circuit training and the right runway for multi-engine aircraft and low level circuit training. Again, check the local procedures before flying. Copyright 2017 Oasis Hong Kong Virtual Page 5
Chapter 5 - Circuit Height Generally speaking, the standard circuit height is 1000 feet above ground level (AGL) for general aviation aircraft, 500 feet AGL for helicopter and 1500 feet for turboprop and jet aircraft. Please take note that it is above ground level. If you have QFE set on the altimeter, it should read exactly 1000 feet when you are at circuit height. If you have QNH set on the altimeter, the reading should be the sum of the field elevation and circuit height when you are at circuit altitude. Fig. 4 QFE vs QNH Once again, this height can vary depending on local procedures. For example, in Hong Kong, the circuit altitude for Sek Kong Airfield is 800 feet AMSL. Chapter 6 - Flying the Circuit Now, let us talk about how to actually fly a complete circuit. Assume it is a left hand 1000 foot circuit. 6.1 Takeoff Perform a normal takeoff roll, apply rudder to counteract yawing tendency. Check airspeed alive, oil temperature and pressure in green and adequate thrust. Move ailerons into wind if there is crosswind. Once takeoff speed is reached, apply back pressure on the control and slowly rotate the aircraft into the initial climb attitude. Let the aircraft weathercocks into the wind. Apply enough rudder for the climb. 6.2 Upwind After takeoff, perform the after takeoff procedure and checklist if applicable. Make sure the aircraft is climbing away, not leveling off or descending. You can use any type of climb for your own practice such as best rate or best angle climb. You should be on the extended runway Copyright 2017 Oasis Hong Kong Virtual Page 6
centreline. Do not drift away, especially if there is a very close parallel runway. Maintain the runway track rather than heading and correct for any crosswind. Fig. 5 Track the extended centreline Climb to 500 feet AGL, initiate a climbing left turn towards Crosswind. Bank angle should not be more than 15 degrees as airspeed is low. Balance the turn using rudder and lower the nose a little bit to prevent speed reduction. Fig. 6 Turn Crosswind Copyright 2017 Oasis Hong Kong Virtual Page 7
6.3 Crosswind Maintain the track perpendicular to the Upwind leg, compensate for crosswind if necessary. Continue climb to the circuit altitude. One of the trickiest part in the circuit is the turn from Crosswind to the Downwind leg. Do not wait until 1000 feet before turning onto Downwind, as the Downwind spacing is not determined by when do you achieve 1000 feet at Crosswind. Instead, the spacing should be the same for every circuit. Therefore, it may be a climbing turn onto the Downwind leg, or a level turn. If there is a large headwind on the Crosswind leg which increases your angle of climb, you may reach 1000 feet well before reaching the correct spacing for your turn. Fig. 7 Downwind Spacing If it is a climbing turn, keep your bank angle at or below 15 degrees. If it is a level turn, maximum bank angle is 30 degrees. During the turn, you may also contact Air Traffic Controller (ATC) with your intention, 'CALLSIGN, turning Downwind, INTENTION'. It is not a must to make the radio call at this point. Aviate, Navigate, and then Communicate. 6.4 Downwind Once you are at Downwind, trim the aircraft, fly straight and level on a reciprocal track to the departure runway track, and apply any crosswind compensation as required. There are different methods to check if you have the correct downwind spacing. For example, the runway should be under and 1/3 inside the wingtip, or you can use your own method. Make sure there is enough spacing, not too wide, not too close. Copyright 2017 Oasis Hong Kong Virtual Page 8
Fig. 8 Downwind Spacing If you have not made the radio call, you should contact ATC now. Specify where you on the Downwind leg (Early Downwind, Mid-Downwind or Late Downwind). ATC may give you landing clearance straight away, tell you what number you are in the sequence or other specific instruction such as extend Downwind. Fig. 9 Early Downwind, Mid Downwind, Late Downwind Then perform the before landing (or whatever you call it, approach, pre-landing etc.) procedures and checklist if applicable. Look for the turning point for the Base leg. You should start your turn when the departure runway threshold is about 45 degrees behind you, or when the runway threshold is 1 1/2 chord distance behind the aircraft. You can develop your own practice as well. Start your turn onto the Base leg, it should be a level turn when you are slowing down and try to get the flaps out. Start your descent once you start to roll out on the Base leg. Copyright 2017 Oasis Hong Kong Virtual Page 9
Fig. 10 Turn Base Leg Just before the turn, you should reduce the power (not all the way to idle of course). When the airspeed is below the Maximum Flap Operation Speed (V VV ), start getting flaps out, may be setting one stage of flaps. Do not go for landing flaps. Fig. 11 Extend Flaps 6.5 Base You should be descending at a rate of 500 feet per minute with approach flaps out at the approach airspeed. Power plus Attitude equals to Performance. Compensate for crosswind, do not let the aircraft drift away or towards the runway. Copyright 2017 Oasis Hong Kong Virtual Page 10
The descend angle would vary depending on the strength of tailwind or headwind. Constantly check the aircraft height with the runway threshold distance. You should be at 750 feet at midbase and not below 500 feet when you are turning final. At about 600 feet, depending on the wind direction, start your turn onto the Final leg. Do not bank the aircraft for more than 30 degrees as you have a low power setting and low airspeed, it is very easy to stall the aircraft with a high angle of bank. Do not overshoot the extended runway centreline, especially if it is a parallel runway. 6.6 Final Rolling out onto Final, align with the runway, make sure you are on the extended centreline. Extend landing flaps. Perform the landing procedures and checklist if applicable. You should have received the landing clearance. Maintain a constant descend path. Adjust power as required. For a runway without touch down zone markings, the aiming point is the runway number. If there is touch down zone markings, the aiming point would be the 1500 foot marker (ICAO Standard) or the 1000 foot marker (FAA Standard). The aiming point should stay constant on the windscreen. Use power to adjust your rate of descend and pitch for airspeed. If the runway starts to go below the windscreen, you are getting high. If the runway starts to go above the windscreen, you are getting low. Fig. 12 Runway Perspective 6.7 Landing and Rollout When you are approaching the runway, keep the aiming point constant on the windscreen. Do not shallow the descend path, fly the aircraft down to the runway. Maintain centreline tracking. There are several phases during the landing and rollout manoeuvres. Approaching the threshold, gently retard to idle thrust, depending on your height, may vary. Since you are so close to the ground, the altimeter is not an accurate tool for determining altitude/height. Over the threshold, you should move your eyesight to the far end of the runway, but keep flying the aircraft down. Use peripheral vision to judge your descend rate. Copyright 2017 Oasis Hong Kong Virtual Page 11
At about 25 to 20 feet, slowly bring up the nose to straight and level attitude, this is the roundout manoeuvre and is used to reduce the rate of descend and bleed off some airspeed. With your peripheral vision, you should feel that the rate of sink has reduced. At about 10 to 5 feet, as airspeed decreases, the sink rate wants to increase again. Slowly bring the nose up to resist the sink but not causing a climb (called balloon) or level off over the runway (called floating), this is the flare manoeuvre. Finally, the main wheels should be touching down first. Ideally, in a general aviation aircraft, the stall warning would sound at the moment that you touches down. Keep the back pressure after touches down as you do not want the nose wheels hitting the ground too hard. Slowly fly the nose wheels down. Fig. 13 Landing Phases Use rudder to maintain centreline tracking during the whole process. Since you are very close to the ground, use as less ailerons as possible to keep the wings level, unless you are doing a crosswind landing. After touch down, use rudder to control lateral movement. Slowly apply brake pressure to the pedals, do not slump on the brakes! Put the controls into wind if necessary. When the aircraft slows down to an appropriate speed, vacate the runway. 6.8 Go Around There are many reasons resulting in a go around, such as an unstable approach, instructed by ATC, windshear, runway incursion, no landing clearance or pilot's own discretion. You can execute a go around as early Base. To execute a go around, apply max power, use rudder to counteract the yawing tendency during acceleration, slowly pitch the aircraft up, but not abruptly. Reconfigure the aircraft such as retract the landing gear and set appropriate flaps. Perform the after takeoff procedure and checklist if applicable. You do not have to rush and inform ATC immediately. After you have make sure the aircraft is in a stable climb, contacting ATC and say 'CALLSIGN, GOING AROUND'. Climb to the circuit height or as instructed by ATC. ATC may issue an early turn onto mid- Downwind. If there is no specific instruction, you should continue flying the Final leg, track overhead the runway and fly into the Upwind, resuming normal circuit pattern. It is the same if you are going around from Base. Configure the aircraft, establish climb or maintain circuit height, inform ATC. Follow the circuit pattern, turn onto the Final leg at the appropriate location. Copyright 2017 Oasis Hong Kong Virtual Page 12
Do not mix up go around and touch and go. Go around is an aborted approach/landing, whereas touch and go is a landing followed by an immediate take off roll without stopping. Chapter 7 - Miscellaneous It is very important to coordinate with other traffic in a circuit pattern. Do not turn onto the next leg unless the preceding aircraft has passed abeam you. For example, if there is an aircraft on Final, you should not turn onto the Base leg until that aircraft has passed abeam you. Fig. 14 Preceding Traffic in the circuit If you are flying in an aerodrome having more than one runway, you have to obtain permission before flying through the extended centreline of the other runway(s). For instance, if you are flying a left hand circuit for runway 09L, on the last circuit, you want to land on runway 09R. You have to get permission before flying through the Final for runway 09L on Base. Copyright 2017 Oasis Hong Kong Virtual Page 13
Fig. 15 Parallel Runway Final Chapter 8 - Airmanship There are some key points regarding airmanship. Do not jam the radio by giving position report on every leg or unnecessary information. In an uncontrolled aerodrome, maintain appropriate spacing between aircraft, extend downwind if necessary. Before making any turn, make sure your left, center and right hand sides are clear. Furthermore, offset to the live side when performing go around over the runway. Chapter 9 - Conclusion Sometimes it could be extremely busy in a circuit pattern, maintain a good awareness of where you are, who is in front of and following you. Thing changes fast in a circuit. Start with normal circuit, then proceed onto flapless circuit, glide approach, crosswind circuit, short field takeoff and landing and night circuit. Most of your basic skills required can be practiced in a circuit pattern. Make good use of it and you will be progressing in a good rate. Copyright 2017 Oasis Hong Kong Virtual Page 14
Appendix A - Reference Materials: CASA VFR Circuit Departures and Joins Copyright 2017 Oasis Hong Kong Virtual Page 15
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This is the end of the tutorial. Copyright 2017 Oasis Hong Kong Virtual Page 17