Proper Ground Reference Maneuvers

Interesting topic with a twist of dealing primarily with visual references outside the airplane instead of the complete how-to guide on flying the maneuver.  That How-To guide can be found in the Airplane Flying Handbook chapter 6. 

I am completely sold on the idea of the “building blocks of learning” as mentioned in the Aviation Instructors Handbook chapter 6.  As a result, my previous blogs with the exception of Visual Steep Turns (I decided to do this series after completing that blog) follow the building blocks of learning.  First, you must know what to look for outside the aircraft to maintain altitude, heading and airspeed for climbs, descents and turns.  You can also argue, that a lesson on how the primary flight controls are in order before this lesson.  Secondly, you need to be able to properly trim the airplane using outside references.  Only after those two building blocks are solid and in place should we place a block on top and teach ground reference maneuvers.  Notice that ground reference maneuvers are in the green second row and are supported by communications and flight information, ground operations, basic flight maneuvers and airport operations.

Some background, to track a heading visually outside the airplane requires the pilot to pick a point outside the airplane that can easily be seen.  When that preselected point starts to move from where it first was on the windscreen an adjustment must be made to continue to track towards the point.  When the point stops moving, that is your new heading to fly to track towards the point.  To maintain altitude, set the pitch attitude and let the airplane settle down and airspeed stabilize a bit.  Properly trim the airplane for hands off flight.  The key to a ground reference maneuver is the proper setup as described in this paragraph. 

For a rectangular course, pick out the course and enter on a 45° intercept.  As soon as you enter the pattern, get your point to track outside the airplane and ensure the pitch attitude is correct.  (Trim is quite helpful here).  During the turns, apply a little back pressure to keep the correct pitch attitude and pick a new point to track.  Continue to fly outside the airplane, until the course is complete. 

 

A turn around a point, as properly described is a rectangular course without the straight segments.  As a result, you simply cannot select a new point to track but a proper setup will include the correct airspeed and altitude with the airplane properly trimmed.  If done properly, the pilot only needs to worry about where the winds are coming from and keeping a constant distance from the point.

 

The S-Turn is simply a turn around a point with a turn in the middle.  The airplane should be properly setup with a stabilized airspeed and altitude trimmed as described before.  Just like its close brother, after the proper setup, the pilot only needs to worry about the winds and crossing the line perpendicular.

 

All of these maneuvers require the pilot to use outside references for best results.  My challenge is for the pilot to perform each of these maneuvers with PTS standards while only using outside references.  If they can do that, the increased information (if used correctly) will make the maneuver a no-brainer.

The Art of Proper Trimming

Have you had issues with holding an altitude?  Does it seem that whatever you do, the airplane wants to oscillate between +200 feet and –200 feet of your intended altitude?  If so, I have good news for you that it can be fixed pretty easily. 

Proper trimming is taught early on in the private pilot syllabus as it is fundamental to everything else that needs to be taught.  It is so fundamental that right after I teach a student pilot what straight and level is using outside references, I teach them how to properly trim the aircraft.  Right after I teach them what a climb or descent looks like, I teach them how to properly trim the aircraft.

After my student has this concept down I will teach them how the airspeed affects the trim of the airplane.  Let me ask you, do you trim for a pitch attitude or an airspeed?  Take a close look at Figure 5-20 from the Pilots Handbook of Aeronautical Knowledge to the right.  One of the first things that you will see is the blue airflow around the elevator interacting with the horizontal stabilizer, the elevator and the trim tab.  The effectiveness of the trim tab is directly related to the velocity of the airflow around the elevator and trim tab.  The answer becomes obvious the pilot will trim for a specific airspeed instead of a pitch attitude.  You may be thinking that you set a pitch attitude but the next time you fly properly trim out the airplane and then slowly add or subtract power and see what happens.

The key to understanding how to properly trim the airplane is that whenever you change your indicated airspeed, you will need to retrim the airplane.  In a Piper Cherokee I used to fly I would teach my students to trim for Vy at 79 knots when staying in the pattern for takeoffs and landings.  Once at pattern altitude, I would instruct them to pitch down to level off and decrease power to stay at 80 knots.  When they start to descend, pull back power a specific amount and keep the 80 knots.  When you add in flaps, allow the airplane to slow down 5 knots each time.  When my students did this correctly, they never needed to keep trimming the airplane. 

All this is said, to make an impression on making sure the airplane is properly trimmed for each phase of flight and how much easier it is going to be to stay within PTS standards.  The steps to properly trim the airplane are:

1. Set the pitch and power for the phase of flight and let them stabilize.  If you are on the initial climb let the airspeed stabilize at V_Y before you finish trimming the airplane.
2. Keep your eyes outside the airplane on the horizon and make sure the pitch attitude does not change during the exercise.   If you are under the hood, make sure the pitch attitude does not change on the attitude indicator but if you can look outside the airplane.
3. Trim the airplane while holding the pitch attitude constant and you should be able to feel the pressure being released from your three finger grip on the controls.  When the pressure is gone, the airplane is properly trimmed.  To test it, let go of the control wheel and see if anything changes. 
4. Repeat as necessary to keep the airplane properly trimmed.

Crosswind Landing Techniques

My second blog on visual flying and techniques I have learned over my short flying career as compared to many pilots.  It is from these pilots that I have learned some of the best techniques.  Pilots with several decades of flying under their belt… safely.  Many student pilots make such a big deal about performing a crosswind landing.  What if I told you that a crosswind landing is no different than performing a normal landing?  In fact, what if I said that I stopped performing normal landings a long time ago?  I bet you are probably thinking that I land with a crosswind and never with calm winds.  Well, that isn’t the case but I treat every landing, whether there is wind or not as a crosswind landing and let me explain why.

B777 Crosswind Landing for Flight Testing

Maybe, I should start with the purpose of a good landing. A good landing is one where the lateral axis of the wheels are perpendicular to runway. The idea is to have zero side load on the tires as they touchdown and bring the aircraft to a stop. In the YouTube video to the right, you can see the aircraft land crabbed into the wind. The tires are controlled by a computer in the cockpit and are perpendicular to the runway.

Extreme Crosswind Landing at EDWB

Somehow I don’t think our small GA aircraft have gear that can rotate to so the aircraft can land in a stiffer crosswind, we will have to resort to a different method to ensure the gear are perpendicular to the runway. Here is my technique. On every landing (meaning a crosswind or not) first use the rudder to align the airplane perpendicular to the runway and then add aileron to keep yourself over the centerline. If you think about it, this is what we do on every landing. It is much easier for a calm wind than it is for a crosswind and I understand that. Notice I didn’t say anything about cross controlling the airplane. It is true that if you perform a proper crosswind landing the controls will be crossed but I don’t think of it that way. The video to the left does a nice job of seeing first the rudder correction to align the aircraft straight down the runway and then aileron correction as the wind starts pushing the aircraft across the runway. (I am not the one flying if you are curious… I don’t live in Europe).

Crosswind Landing in a C-172

One thing the video did was to keep the crab into the wind till just before roundout when the corrections were applied. I personally like this technique and use it often. For less experienced pilots I have them put the corrections in early so they can see what it feels like. Like in the video to the right which again thought was a nice landing.

I drill into their head, rudder to keep the nose straight and aileron to keep yourself over the centerline.  Period.  One technique for every landing.  On a landing with no crosswind, rudder and aileron should be neutral but the pilot is thinking… “Whatever it takes to keep the nose straight with rudder and whatever it takes to keep myself over the centerline”.  For instructors reading this, remember the laws of learning.  Primacy:  Things that are learned first are remembered (my definition).  I like what the Aviation Instructors Handbook has to say about it.

Primacy, the state of being first, often creates a strong, almost unshakable impression and underlies the reason an instructor must teach correctly the first time and the student must learn correctly the first time.

The other thing to remember after touchdown is to keep flying the airplane.  Keep the corrections that worked in until the airplane is no longer flying aerodynamically meaning, the control surfaces don’t have enough force to change things.  Especially, on the windy days remember to use proper taxi technique for both the aileron and rudder.