PPL Practical - Preflight Procedures

Introduction

There may be a tendency to only emphasize safety during actual flight, but a pilot must maintain vigilance from before the engine is started, to the time the aircraft is safely tied down and the engine stopped.
In the flight sim world, aircraft don't fail unless you tell them to, and it is very tempting to just hop in and fly. Again, there's nothing wrong with that if that's what you want out of flight sims, but the experience would be a lot more immersive if the more mundane aspects of flight (ie. checks) are taken seriously too. 

In this regard, payware aircraft are ideal because most offer the option of conducting a walkaround. In particular, the REP series by SimCoders is excellent because the aircraft include pre-flight checklists which illustrate what each of the check entails, and what you should expect to see. This solves a common problem for many flight simmers with no real flight experience, which is that they have difficulty following the checklists because they don't know what the steps listed mean. 

Improper handling of the REP aircraft may also result in wear-and-tear and failures over time, meaning that there is actually a point to doing these in-flight checks because things may actually need replacement / repair. 

Preflight Assessment 

  • Comes in 2 parts:
    • Inspecting the aircraft’s airworthiness status 
      • Logbooks, maintenance records 
    • Making a visual inspection of the aircraft 


Airworthiness status
  • While maintenance may be the responsibility of the owner of the aircraft, the pilot is solely responsible for ensuring its airworthiness
  • It is important that records and logbooks be kept up to date, and it is advisable that these records not be kept in the aircraft itself. 
  • Some FAA requirements relating to maintenance

  • Airworthiness status review: 
    • Ensure, according to all the records, that all of the above requirements, or the requirements as set by another country, are met. 

 Visual Inspection
  • Should first start with a “macro” view approaching the ramp 
    • Check for imperfections that can’t really be seen as easily in a close-up inspection, such as asymmetric wings, bent parts or imbalanced landing gear. 
  • Consult POH for specific pre-flight inspection procedures for each aircraft but some common checks include:
  • Interior
    • The door should fit tightly, no cracks on the windscreen, seats and seatbelts are secured
    • Instruments give readings that make sense - the altimeter, ASI, the VSI should read 0 
    • Only the VSI may be zeroed by the pilot; everything else must only be altered by a professional 
    • Sensors do not show readings if they are yet to come alive
  • Wing outer surfaces and Tail 
    • Ensure that there is no deformity especially along spar lines - ie wrinkling, dents, which may indicate structural damage or failure. 
    • Check the rivets and bolts for security 
      • Cracked paint could be a sign that the rivet has worked its way free 
    • Check the leading edges of the wings for dents, scratches, ice, dirt, etc 
    • On metal aircraft, non-structural parts eg. wingtips, fairings, may be made out of plastic or fiberglass, which are susceptible to cracks. It is common practice to stop these cracks by drilling a hole, known as "stop-drilling" 
      • Ensure no new cracks have formed, and the parts are still in airworthy condition 
  • Fuel / Oil
    • Avgas comes in 3 grades
      • 80/87 - dyed red 
      • 100LL - dyed blue 
      • 100/130 - dyed green
    • Engines rated for one grade of fuel can run on higher grade avgas, but not the other way around
      • May cause detonation and severe damage to the engine 
    • Jet-A fuel also cannot be run on gasoline-based engines. 
      • It may work long enough for the plane to get airborne, but the engine will fail. 
      • Jet-A is kerosene based and smells different from avgas 
      • It is colourless though it may appear dyed if mixed with avgas 
      • For this reason, Jet-A and avgas nozzles are deliberately designed differently. Jet-A nozzles flare out near the end, while avgas nozzles are thin at the end 
    • Fuel capacity may be affected by attitude - ensure the aircraft is on level ground
      • Visually inspect the level of fuel in the tanks 
    • Check for fuel leaks - any signs of a fuel leak should be reported 
    • Check for water contamination - can be quite common for water to collect due to condensation. 
      • Draw samples from each of the fuel tank strainers to check for water and other contaminants like sand 
      • Continue until no more is found - if excessive, report it
    • Check fuel tank vent for blockages. 
      • If air cannot escape, fuel starvation will resul
    • Check for sufficient oil and use the appropriate type 
      • Oil darkens in colour over use as they trap contaminants.
      • Piston engine planes use a small amount of oil each flight 
    • When the engine is cold, the dipstick displays a quantity of fuel higher than reality. 
  • Landing gear, brakes, tires
    • Braking mechanism
      • Free from rust 
      • Fasteners secured 
      • Free from hydraulic fluid  
    • Shimmy Dampers 
      • Used to damp oscillations in the landing gear 
      • Check that it is secured 
      • Free from hydraulic fluid / other damping fluids that may be used 
      • Crack-free 
    • Bungee Cords 
      • Used on some planes (primarily tail-draggers) to absorb load
      • Ensure good condition of bungee cords
    • Landing Gear Bay 
      • Check for wrinkled skin (may be caused by hard landings), loose bolts or other damaged areas. 
  • Engine and propeller
    • Start with a general inspection of fasteners / rivets on the cowling 
    • Inspect propeller spinner for cracks and ice 
    • Ensure spinner and propeller is properly balanced on the crankshaft 
    • Inspect for signs of oil leaks, fuel leaks, and hydraulic fuel leaks 
    • Air filter should be inspected for signs of blockage, like nests or dirt. 
    • Prop care

Environmental Risks and Management


Flight Deck Management 


Engine Starting 

  • Procedures laid out in the POH must be followed especially strictly 
  • Prior to engine start, pilot is to ensure ramp area is clear of people / equipment / hazards both in front and behind the engine 
  • At all times, the beacon light must be turned on 
  • For night operations, the navigation lights should also be turned on 
  • Always call "CLEAR" or "PROP CLEAR" before starting the engine
  • Ensure brakes are in, and advance throttle to the right rpm for engine start 
    • Usually around 1000rpm to allow oil pressure to rise and but low enough to prevent wear and tear due to insufficient lubrication.
  • In low temperatures, oil of suitable grade must be used given the temperature range and engine preheating
  • Ensure oil pressure is advancing towards optimal range within the right amount of time
    • Usually within 30 seconds
    • Shut down if not achieved, as damage to engine may result. 
  • Engine starters are not designed for prolonged, high intensity use. 
    • If engine fails to start, prevent continuous starter use for longer than 30 seconds without a cool-down period of 30 seconds - 1 minute. 
    • On rare occasions, engine starters may continue to be engaged after engine start, indicated by a large draw from the ammeter. If this happens, shut down the engine immediately. 
  • Pilot should be familiar with the feel, sound, and smell of a proper engine start. 
  • Be mindful of propellers and engines when removing chocks. 
  • Hand Propping
    • Should be avoided except as a last resort 
    • Should only be done with at least 2 trained people  
      • One person responsible for directing, and pulling the prop through 
      • The other sits in the plane to ensure brakes are set and everything is running normally. 
      • Both should agree on the flow of the procedure beforehand.
    • Gain a proper footing before starting, make sure area is clear of debris which may cause the "prop-spinner" to slip 
    • Everything to be set up for a normal engine start, except that magneto switch is OFF. 
    • Communicate between both people 
      • Brakes SET, magneto OFF, fuel ON, throttle CLOSED 
    • "Prop-spinner" adjusts the prop such that the downward-facing prop is slightly above horizontal
    • "Prop-spinner" says "BRAKES AND CONTACT"
    • Person inside checks brake, turns on the magneto switch, then repeats. 
    • "Prop-spinner" used both palms of his hands (so fingers don't get caught) to swing the prop downward rapidly, while quickly taking a step back   

Taxiing


  • As always, accomplish all tasks listed out in the POH.
  • Maintaining situational awareness is imperative.
  • Pilot should be familiar with the airport layout 
    • Have a chart handy 
  • Ensure that the plane clears all obstacles 
    • If there is doubt, get out and physically check the clearance. 
  • When taxiing, pilot's eyes should always be looking outside, scanning side to side 
  • Safe taxiing speed 
    • Slow enough that when the throttle is closed, the plane can be stopped promptly without use of the brakes
    • Do not turn at high speed 
  • Centre the aircraft on the taxiway 
    • Some taxiways may have signs and lights that will pose a hazard to aircraft if not centred. 
  • Turning should be accomplished with both the nosewheel / differential braking and rudder, if the axes are not linked. 
  • Both brakes should be tested individually for operation as soon as the aircraft begins moving. 
  • Instead of continuously applying brake pressure (which may result in overheats), apply brakes in short bursts when controlling speed. 
    • Throttle should always be at idle before brakes are applied 
  • It is advisable to always have the nosewheel pointing forward when coming to a stop to prevent side load and to make it easier to start taxiing again. 
  • Taxiing provides a good opportunity to verify instruments are giving readings that make sense
  • Taxiing with a crosswind: 
    • "Climb into a headwind, dive away from a tailwind". 
    • Prevents the wind tipping the aircraft over
      • The wing closer to the direction of the wind (the "upwind wing") tends to be lifted up by the wind. 
    • Manipulation of the elevators more relevant to taildraggers 


Pre-Takeoff Check 

  • Usually performed after taxi to a run-up area near the runway 
  • Many engines require oil temperature to reach a certain temperature before takeoff
    • Engine is allowed to reach that temperature during run-up. 
  • Suitable place would be free of debris to prevent damage to the engine or propellers
  • Before beginning, the airplane should be allowed to roll forward a bit to ensure the nosewheel is properly aligned 
  • Even while during the run-up, the pilot should maintain good situational awareness and continue to glance outside of the cockpit 
  • Air-cooled engines may overheat if the run-up is prolonged since the airplane is stationary. 
    • Recommended to position the engine to face the wind
    • Cowl flaps (if applicable) to be set as per POH's instruction 
  • Check systems as per POH's instruction, common ones: 
    • Fuel system 
      • On 
      • Correct fuel tank is selected (I actually overlooked this one flight and wondered why my airplane kept banking to the right!)
    • Trim
      • At take-off position, ailerons and rudders usually neutral 
    • Flight Controls 
    • Engine operation 
    • Electrical system 
      • Voltage and current within limits 
        • Ensure that battery is charing 
    • Vacuum system 
      • Responsible for function of gyroscopic instruments (attitude indicator, heading indicator, turn coordinator) 
      • Ensure within limits 
      • Ensure enough time is given for them to properly spool up before taking off
    • Flight Instruments 
      • Altimeter 
        • Pressure must be set to show an accurate reading, information can be found on METARs, from ATC, etc. 
        • Below transition altitude, use local pressure readings; above, use standard atmospheric pressure at sea level, 29.92 inches of mercury (29.92 in-Hg) or 1013.2hPa.
      • Heading Indicator or Horizontal Situation Indicator (HSI)
        • Should be aligned to compass (true north) 
        • In light aircraft, the heading indicator should be checked against the compass every 15 minutes to correct for drift 
        • Heading bug can be set to runway heading, or heading as assigned by ATC. 
    • Avionics
      • Radios 
        • Communication and navigational radios should be set to appropriate standby and active frequencies (tower, departure, VOR frequencies, etc.)
      • Transponders 
        • Squawk the right code (assigned by ATC or 1200 for VFR in the US if not assigned by ATC) 
      • Autopilot
        • Set altitude / headings assigned by ATC if applicable 
    • Take-off Brief 
      • Should be conducted by yourself even if no passengers present 
        • Type of take-off (normal, short, soft) - covered in later chapters
        • Take-off runway 
        • Surface winds (direction / speed) 
        • Lift-off speed Vr 
        • Initial heading on take-off
        • Initial altitude 
        • Emergency plan
          • Engine failure before Vr
          • Engine failure after Vr with runway remaining 
          • Engine failure after Vr without runway remaining 
          • These are also covered in later chapters 
    • Final checks as the take-off roll commences 
      • Take-off thrust set
      • Engine RPM
      • Smooth operation of engine (ie no knocking)
      • All parameters "in the green" 
      • Doors and windows latched? 
      • Keep aircraft on the centreline
    • Many of the items stated above require some level of understanding, either from the PPL Theory portion, or from later chapters. As we learn more, the things here will become a bit clearer.  


Misc
  • Recommended that refueling be done, all passengers are off the aircraft so as to achieve a stable, level attitude. 
  • Baggage loading should be supervised by the pilot so he can ensure load and balances are within limits 
  • Passengers should only be allowed to move about within restrictions placed by the pilot to ensure safety and security 
  • Use of magnetic north in aviation

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