Peter's Flight Log

Watch and listen to the complete video and audio from the flight. No video camera operator errors this time. I have even left in my most embarrassing ("brain-dead") moments.

It's Wednesday afternoon. I had a good break after this morning's flight (hour 7), and the weather is still very good. A little more gusty wind compared to the morning, but nothing too serious.

So, this is it, I'm "GO" for circuits.

I am very excited because this is what I will be training for for the next few weeks. This is a basic component of my training for the RPL license. In circuits, I have to apply everything I have learned so far, in quick succession, and without error. A circuit ends with a successful landing, and to achieve a successful landing the circuit maneuvers have to be successful. Statistics show that a great deal of accidents happen towards the end of a circuit, when the pilot and the plan transitions from the downwind leg to base and final. That's when the plane configuration and it engine power settings, attitude, and altitude change significantly and things can go wrong very quickly.

But, let's not think about this right now. The plan is that Bob will demonstrate the first circuit with a touch-and-go, and I will do the next four or five.

What is a circuit?

I should explain what a circuit is in case you are not familiar with this aviation term. And to make sure there is no confusion, I am referring to "circuits" in the context of aviation, not electronics.

In aviation, a circuit is a specific flight path that an aircraft follows when taking off, flying around an airport, and landing. It's like a racetrack in the sky that helps pilots, air traffic controllers, and other aircraft know where an airplane is going. This makes it easier to manage air traffic and ensures safety.

A left circuit looks like this:

A standard circuit has four main parts: the upwind leg, crosswind leg, downwind leg, and base leg. The final approach and landing follow the base leg. Each leg is a straight line, and the turns between them are usually 90 degrees.

1. Upwind Leg: After takeoff, the aircraft flies in the same direction as the runway. This is the upwind leg.
2. Crosswind Leg: The aircraft makes a 90-degree turn to the left or right. It flies perpendicular to the runway for a short distance.
3. Downwind Leg: Another 90-degree turn leads to the downwind leg. The aircraft flies parallel to the runway but in the opposite direction of takeoff.
4. Base Leg: A third 90-degree turn takes the aircraft onto the base leg, which is perpendicular to the runway again but closer to the landing point.
5. Final Approach: After the base leg, the aircraft makes one last 90-degree turn to align with the runway for landing.

Aircraft usually fly circuits at a specific altitude, often around 1,000 feet above the ground. For Camden airport, this means around 1,350 ASL (Above Sea Level). The speed varies depending on the type of aircraft but is generally slower than cruising speed to allow for safe turns and landing. For the Cessna 172, we aim for speed of 70 knots on base, and 65 on final.

Pilots communicate their position in the circuit to air traffic control and other pilots. This is crucial for coordinating takeoffs and landings and for avoiding collisions.

While the standard circuit is left-handed, meaning all turns are made to the left, some airports use right-handed circuits. Pilots need to know the type of circuit at each airport and follow it precisely.

To help me with learning the circuit-specific procedures, I used this diagram, compiled by Flight school:

The circuits diagram above shows the terminology (i.e. "upwind", "crosswind" etc., the altitudes that must be maintained on each leg, when to turn, the checklists, and when to complete each checklist.

Checklists

While flying in the circuit pattern, there are a few checklists that are important to complete correctly and in time. Unlike the checklists on the ground, I will eventually have to memorize the circuit checklists. This is because there is little time to look them up while flying, maintaining separation, talking to ATC etc. 

You can see the checklist acronyms in the circuit diagram above. Here's what each one means:

B.U.M.F.I.S.H.:

• B: Brake, must be not-engaged.
  
• U: Undercarriage, must be down (even though the Cessna 172S does not have a retractable undercarriage).
  
• M: Mix (fuel) must be fully rich.
  
• F: Fuel must be sufficient for landing and go-around.
  
• I: Instruments must be working.
  
• S: Switches must be correct, i.e. strobe, landing lights etc.
• H: Hatches and fasteners must be secure.
  

H.S.S.:

• H: Heading must be aligned with runway.
  
• H: Height must be 1,000 ft AGL.
  
• S: Spacing from other aircraft must be sufficient.
  
• S: Speed at 110 knots.
  

300 feet checks:

• Temperature in green.
  
• Pressure in green.
  
• Flaps extended as is appropriate.
  

There's a lot to remember and do safely within seconds. For now, I use notes, and Bob is there to remind me until all this is ingrained in memory.

The flight

The ATC service was back online after the outage in the morning, so I made the call to ask for clearance to start the engine and do circuits. After doing the pre-flight checks, I contacted tower like this:

"Camden ground, this is Alpha-Hotel-Hotel at the Scouts Hangar, requesting permission to taxi for circuits, received information Bravo".

ATC responded with instructions and clearance, to which I responded:

Holding point Alpha, runway 06, Alpha-Hotel-Hotel.

I could now start the engine, taxi to holding point Alpha (while doing the taxi checks) where I'd do the pre-take-off checks. I then taxied to holding point Alpha, waited for some traffic to clear, and radios Tower to let ask for permission to take off. Permission was granted, and we're off!

I did the take off with a bit of crosswind, but felt that I help directional control reasonable well. Bob took over to do the first circuit demonstration, with a touch-and-go at the end.

It was then my turn. I had already done a few take-offs in the last two flights, and I think I did the first take of well enough. As this time my objective was to join the circuit right after take off (and not to depart for the training area), I had to be more aware of my position and altitude. Bob pointed out a couple of landmarks for the turn from upwind to crosswind (a small block of houses) and from crosswind to downwind (a bend of a river).

From take-off to upwind and crosswind I was using power and pitch to ascend to the circuit altitude of 1,350 feet, while taking the first turn at 15°, and the second at 30°. This is because by the time I got to the second turn (to downwind), I was already at circuit altitude.

Then, barreling downwind, I did the H.S.S. and B.U.M.I.S.H. checks, and started re-configuring the plane for the base leg.

Reduced power to 1,800 RPM, maintain 1,350 ft, extend 10° flaps after speed fell below 110 knots, trim and balance. At 45° from the threshold, start the left descending turn at 30° bank of roll. On base, drop power to 1,500 RPM, descent (not below 500 feet!), extend flap to 20° once speed was in the white arc, and try to get speed around 70 to 75 knots around the middle of the base leg. Then anticipate the last left turn to line up with the runway, do a 30° left turn, extend full flap, keep speed at 70 knots, and aim to the runway with wings level. This is where I need to use power to help with the glide scope, especially if I'm too low. 

At 300 feet above ground do the "300 feet checks", call ATC to let them know I'm doing a touch-and-go (Bob did this as I was a bit overloaded at this point), keep wings level, and use power as required.

If my aim is correct (which it was, except once when I was to high and had to do a go-around), the plane will be at a good height over the runway threshold. Then keep the speed at 65 knots using attitude, close the throttle, fly level to the runway keeping the nose high to ensure a good rate of sink and that the rear wheel touch the runway first.

Once  touched down, keep on the center line. Since we are doing a touch-and-go, while keeping the plane on the center line, retract flaps, apply full throttle (mix is already rich) and take off.

I felt good about this procedure. Conditions were good, with only a reasonably small amount of cross wind.

I repeated the circuit another four times, with one case were I was too slow to change configuration in the downwind which caused the plane to be too high for a safe landing, so we did a go-around.

I am looking forward to more circuit training next week.

Debriefing

I felt good after my first circuit. I felt significant mental strain, and that my reactions were occasionally slow, unless I had anticipated a change. I also experience the go-around, which was a result of me getting fixated about an indication in the instrument panel (I think it was the engine RPM) and not keeping correct altitude with attitude (that's how I ended up too high).

All these were things I can improve in the next training session.

Bob's feedback was that I did reasonably well considering my level of experience and the variable cross wind, and there's a few things to improve on. Specifically:

• Trim. I must set the attitude I want to keep with the yoke, and then trim to relieve the pressure on the yoke.
  
• Airspeed. This must be 70 knots on base, and 65 on final. Use attitude to achieve these airspeeds.
  
• Power. Use power to control the rate of descent (not the speed, as I was doing!). Reduce power if I'm too high, and increase it if I'm too low.
  
• Anticipate. Whether it is reaching the desired altitude or heading, anticipate when this will happen and begin exiting from the ascent, descent or turn to end up where I want to be. If I'm late, I will overshoot my target.
  

So, next week, I'll be working on these areas.

I can't wait!

Flightradar24 captures information from the aircraft's transponder and produces this animation. This is the animated track of our plane in this flight.