Back in the (High Wing) Saddle

Flight Debrief, Cessna 172R VH-LWX, 0.8h, YMMB.

A busy month of travel and work meant no flying in May. Although I did have a scheduled nav down the Great Ocean Road to Warrnambool and back with Dad, we scrubbed it due storms and weather on the day.

That cancellation prompted me to look at the economics of where I was booking my flights, and to explore other options. My last flight, a 2.7 hour Nav solo, consisted of at least 0.5 hours of taxiing, for which I was billed. While I understand this is accepted practice, there are a number of reputable flight schools that only charge for flight time. This, and lower overall solo rates, prompted me to contact Learn to Fly at Moorabbin Airport. LTF's fleet consists of Diamond, Sling, Piper, and Cessna aircraft; the latter 172R model being my choice given its performance similarities to the Piper Archer, particularly the 110-120 KIAS cruise speed, and the attractive hourly hire cost.

I was impressed with LTF's quick and informative response from my initial inquiry, with Josh, the Grade 3 instructor I was assigned, sending through the C172R Pilot's Operating Handbook (POH), Emergency Checklist, and Normal Checklist. Back to ground school...

Ground School - C172

I enjoyed the overall approach that LTF used in preparing me for my check flight in providing me with the materials I needed to self-direct my learning. I found Cessna's POH to be laid out and structured much more like the PC-9/A & CT-4B manuals that I recall having to learn from: limitations, emergency procedures, normal procedures, performance, and aircraft & systems description, with supplements for the avionics stack. The quick-reference checklists highlighted boldface items, those that I needed to committed to memory. Plus, prior to taking LTF's aircraft out, I need to satisfactorily complete an 'endorsement' test for the C172, which asks questions about procedures, aircraft systems, and other important information.

An interesting point I learned is that the C172R is certificated in both Normal and Utility categories, depending on payload weight. The C172R's Utility categorisation authorises spinning, which was prohibited in the Piper and Archer. Given that the ATSB recently released a report that highlighted concerns that some flying training organisations may be conducting incipient spin training in aircraft not approved for intentional spinning, and noting that the Piper wasn't authorised for spins, I was pleased to learn that the Cessna is.

There were other few major differences between the PA-28 Warrior and Archer, and the C172R, such as:

• No fuel pump. While there is an auxiliary fuel pump, the primary fuel pump is engine driven and always on.
• No carburettor heat. Cessna's 172R is powered by a fuel-injected Lycoming, versus the Piper's naturally aspirated engine. No carburettor means no risk of carburettor icing, meaning no carburettor heating system.
• Fuel Selector Valve. Rather than alternating between the Piper's left and right tanks every 30 minutes, the Cessna has an easy 'Both' selector that is the primary selection.

These three systems change the overall circuit checklist flow a bit, particularly after takeoff, on downwind, and on short final. I did learn a bit more about these systems, as I was intrigued by their absence.

Fuel Pump

In the Piper, the fuel pump is normally selected on during downwind as part of the pre-landing checks. The fuel pump assures constant, uninterrupted fuel flow during the critical takeoff and landing phases.

On the Cessna, the engine-driven fuel pump acts as the primary pump. The auxiliary electric pump can supply fuel should the primary pump fail, and it also supplies fuel pressure while starting and is used to prevent vapour lock during flight at high altitude. Not needing to switch on a fuel pump during pre-landing checks, and not needing to remember to turn it off on climb-out significantly simplifies the checks, making it feel as though something has been forgotten.

Carb Heat

Carburettor heat is used to prevent icing in the carburettor as a result of fuel vaporisation and low temperatures. Icing can restrict the flow of the fuel-air mixture and reduce power, even choking the engine if enough airflow is restricted. Pre-landing checks in the Piper required carburettor heat on, as engine RPM will be reduced on base and final legs. Reducing the power also lowers the manifold pressure, decreasing temperature, and thus increasing the likelihood of carburettor icing. Carb heat mitigates this risk.

Fuel-injected engines, like the Cessna 172R, do not require carburettor heat as they are not as prone to icing because "the gasoline is injected as a steady stream just upstream of the intake valve, so evaporation occurs as the fuel/air mixture is being drawn into the cylinder, where metal temperatures are higher."

On short final in the Piper, carb heat is turned off when committed to land as it incurs a power reduction when selected, and this power is important in case a go-around is required. Again, not having to select carb heat on, or turn it off on short final, makes it feel as though something is missing.

Throttle & Mixture Control

Cessna's throttle and mixture control arrangement is quite different to Piper's, with Cessna using a push-pull knob (Vernier throttle) versus Piper's more lever-style arrangement. I previously wrote about the importance of finding a comfortable place to rest my hand on the Piper's throttle quadrant so that one hand was handling the control column and the other firmly and accurately able to adjust throttle. I would liken the importance of this as similar to when driving a car, resting one's heel on the floor for stability and leverage, and using the front part of your foot to control the pedal pressure. Driving without your heel on the floor feels very odd, and makes it difficult to make precise, minor power adjustments. Although it might not look it, I quickly found that resting my hand on the throttle knob was easy and comfortable. Apparently, the Vernier throttle is easier to precisely adjust compared to the quadrant style.

Walk-around

My instructor had booked a 16:30 off-block time, and the plan was to fly to the training area, practice some stalls, and then return for a few standard circuits. With sunset at 17:08 and last light thirty minutes later, I was looking forward to some dusk flying. I arrived at LTF at 16:00 for paperwork and licencing checks, and met my instructor. We realised we both had similar backgrounds! Josh took a hiatus between first flying in 2006, to next flying in 2011, and then again in 2016 when he started his commercial pilot journey. Interestingly, Josh also spent some time in the Royal Australian Navy, and we compared dates and logbooks and realised we missed crossing paths by about a year, but recognised some of the same names in our logbooks.

Instructor rapport makes a big difference, and I was quickly at ease with and around Josh. I told him I was feeling pretty rusty having not flown for over a month, and that I was just beginning again. He understood, and took my lead in answering my questions and guiding my learning. Josh even threw a briefing quiz question at me, 'what is the glide speed?' To which I answered correctly (65 knots), and without getting the sweats on!

We briefed that we wouldn't fly to the training area due lack of daylight and time, and we'd do a few circuits to give me some feel for the aircraft's handling. Preflight walk-around itself was pretty straightforward, the main difference being the high wings for fuel contents check. It's also nice having two doors for getting in an out!

Flight

Taxi

Following the checklists, I felt they flowed easily, including those that I hadn't practiced for awhile, such as instruments checked and set, radios set, and take-off safety brief. We were using runway 17L for circuits. I made a minor radio error, a common theme for the flight, that I put down to being out of practice.

Demonstration Circuit

My instructor took over after line-up checks, and flew the entire first circuit to show me the attitude cues, power settings, and general flow. He gave a good tip on downwind, to aim for four large buildings that are in Oakleigh, rather than tracking a heading. And a good turning point for base to final is the go-kart track north of the airport.

My Circuits

On climb-out, my instructor handed over control. Climb was straightforward, a slight wheel vibration on takeoff which disappears as the aircraft accelerates. We use best rate of climb (Vy 79 KIAS) for climb, the attitude being pretty high with the horizon cutting the Artificial Horizon. At 500 feet, executing a gentle 15° turn to crosswind, I found I needed to use a lot more rudder than I did in the Piper to counteract adverse yaw and to keep the aircraft in balance, and that the Cessna was sensitive to over-balancing with too heavy a rudder input. This balancing feel was consistent throughout the circuit, and I enjoyed having to use more rudder than I was used to as it requires more manual flying.

On upwind, I consistently reached 1,000 feet at about the same time as I needed to turn downwind, and usually I would level off, reduce power to 2,100RPM, configure, and then turn. Instead of making the radio call when established on downwind, I was advising "LWX, turning downwind," which created a bit more time. Lined up with the buildings on downwind, I found there was plenty of time for BOUMFISH (instead of BUMFOCH for the Piper) pre-landing checks. Spacing on downwind was consistent with the runway cutting 3/4 of the way up the wing spar, and speed reached about 100 knots. Josh's additional bit of gouge was that it's also OK to have the runway halfway up the spar, meaning you're closer to the runway, for slightly quicker crosswind and base legs.

On reflection, I found late downwind and the base turn a little complicated. This was because I was cramming several things in just before the base turn point, i.e. reducing power to 1,500RPM, extending flaps to 10° below 110 knots, adjusting my attitude to maintain height, and trying to monitor speed, just prior to looking out and turning. The correct sequence should be to (1) initiate the turn, and (2) reduce power to 1,500RPM during the turn. Keep applying backpressure to maintain height, and this will reduce airspeed below 85 knots for the second stage of flap. As air speed decreases to 75 knots, set descent attitude and trim. Thanks Ryan!

Base and Final did not feel rushed in the Cessna, with plenty of time to turn onto extended centreline and correct aimpoint and aspect on early final. As soon as wings are level on the final turn, set flaps 30° and focus on aimpoint-aspect-airspeed (70 knots). Landing felt easier than in the Piper, possibly due to the reduced ground effect thanks to the Cessna's high wing, as well as having more peripheral height and speed cues. I would bring the power to idle when touchdown felt imminent, and then hold the nose up as the aircraft sank. On rereading that last sentence, it seems very imprecise; my estimate would be at 2-3 metres off the ground I would reduce power to idle, and float the aircraft down by gently increasing attitude to runway through glareshield.

Four circuits in total, one was Josh's, the other three were mine, and by the time of the final full stop it was almost full dark, which made for a novel experience given I don't have a night rating.

Learning Points

• Attitude high on base. My instructor's main learning point for me was that as I levelled out on the base leg, I tended to keep my attitude too high with flaps at 20°. This decayed the speed below 75 knots and I had to correct.
• Base turn sequence focus:

1. Lookout and 30° medium level turn
2. During the turn, bring power back to 1,500RPM
3. Increase backpressure for 1,000 feet maintenance (CTAF call during the base turn too)
4. Check airspeed and if below 110 knots, set flaps 10°
5. Roll onto base, level wings, trim.
6. Speed below 85 knots, set flaps 20°, trim.
7. Monitor speed for 75 knots, then set descent attitude (half-ground, half-sky) and trim.

• Wide of centreline on upwind. On my last circuit IFR traffic was inbound at 1,500 on my reciprocal heading as I was climbing upwind. This distracted me and my instructor pointed out that I had drifted right towards runway 18R. During night circuits with only one runway operational, this wasn't an issue, but during the day it would have been.
• Radio/Telephony and phraseology. I made minor errors on calls in the run-up bay, downwind, and after landing. Practice, or better yet, go flying more often.
• Rudder. Be mindful of adverse yaw, using rudder for coordinated turns, and that too much rudder will also unbalance the turn.
• Trim, trim, trim. There is no electric trim on the C172R, just a centre mounted wheel for elevator trim. Figure out the rules of thumb (i.e. two turns down at flaps 20°) and proactively trim.
• Practice Forced Landing. With no fuel pump or carb heat, CFMS checks in a PFL are somewhat unnecessary. Can go straight to FMOST. Sequence:

1. Glide attitude 65 knots and into wind / right shoulder into wind.
2. Select field, identify high key 2,500' / low key 1,500'.
3. FMOST. Fuel (BOTH, aux pump ON, contents check), Mixture FULL RICH, Master ON, Oil Ts & Ps, Switches (Magnetos cycle both-left-right), Throttle cycle.
4. Squawk 7700, Mayday call
5. Passenger brief.
6. Shut down and BUSH - Brakes off, undercarriage down, switches off, hatch open, harnesses on.

• Analogue cockpit. I find the analogue layout easier to interpret and scan quickly, and as I reflect on that thought, I realise it is probably out-of-date and younger generations would wonder why I cling to the past. I will try to be more proficient at understanding and using digital integrated instruments, as well as aids such as the Garmin G1000 and electronic flight bags.

Next flight

Hopefully another in June, depending on aircraft availability and weather. I'll probably either go to the training area and consolidate handling, as well as try to fly some circuits at a CTAF aerodrome, which may enable a short nav.