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Contents:


Prelanding
The prelanding begins well away from the destination airport. From cruise flight we must plan our descent. This usually means we must decide at some point to change altitude into airspeed. It is usually, but not always, done by planned reductions in power and mixture adjustments as required. There are advantages to getting the ATIS as far out as you can. Sure, the ATIS may well change before you arrive but not so much as to affect the advantages of prior knowledge.

From the ATIS you have planned your arrival to include selection of your initial call-up point, radio procedure planning, situational sensitivity, best pattern entry, and your 'what if' options. At a constant point in your pattern arrival you complete the initial components of the prelanding checklist.

For non-complex general aviation aircraft, my preference is to have a pre-landing count system that uses my fingers for up to ten items. As I identify an item I use an appropriate finger. Others go through the process and then check the list. However it feels best to you, you should always run through your prelanding checklist.

Prelanding in the options pattern abbreviates the checklist into gauges and instruments, traffic and clearance. Options approval from ATC gives you a choice of a touch-and-go, go-around, stop-and-go, and full stop. ATC may preclude any of these at their option for traffic considerations.

Copy ATIS........Think............................GUMP
Fuel/Mixture.......Gauges/instruments.......Go-around procedure
.........................Type of entry................ Position and traffic
..........................Altitude......................... Frequency
..........................Pattern altitude

Beginning Landings (Instructor)
On our first inter-airport flight, I select a practice area somewhere in between to do a series of landing patterns at altitude. I use the same headings as would be expected at our destination airport. I usually select a climb to 4200' over some hills that will keep us within 3000' of terrain. At 4200' we enter the downwind heading, the pilot performs the pre landing check. At the 'numbers' he applies carb heat, reduces power to 1500 RPM, moves the trim wheel down three full turns using only the index finger, applies sufficient back pressure to maintain 4200'. He allows the aircraft (C-150)to decelerate to 60-knots while holding heading and altitude. This is a vital series of skill applications. It may need to be repeated several times to acquire a satisfactory level of performance. It usually helps to have the student say aloud what he is doing. This information on the tape recorder is very helpful for later review.

The momentum of the aircraft from the numbers to the point that the preceding configuration is achieved covers just the distance to the 'key' position. This is the point at which the base turn is commenced and descent begins. As with all turns, clearing is performed, pressures and added and released on yoke and rudder to smoothly make 90-degree turns in 30-degree banks at 60 kts. (Remember, we practiced these descending banks and turns earlier in our training.)

The difference in this lesson to prior trim and flap lessons is that we are practicing the landing sequence. All turns will be in left pattern until the go around or in right pattern until the go around. In line with the teaching/learning precept that a first learned procedure will also be the first reaction in an emergency, the go-around is the first taught landing operation. This process is first introduced with an imaginary 'ground level'. At altitude and airspeed of 60 kts the student applies a count of 4 to the flaps. As the flaps go down, forward pressure is applied to the yoke to maintain 60 kts. One full upward turn of the trim should keep the speed at 60 kts without any yoke pressure. After simulating downwind, key position, trim, flaps and airspeed, base and final the go around is performed. The sequence of SMO O O TH power C. H., rudder, flaps up 20 degrees, airspeed of 65, climb attitude, flaps up, and trim should be repeated as on many previous flights. From this 'good beginning' the remainder of the pattern usually follows quite easily.

Stabilized approach
The stabilized approach has no peer in affecting good landings. Set as many constants on the landing approach as you can. Set the power to a predetermined constant. Know the trim movement, and setting required for every change in power and flap change. On final establish your flight glide path and sideslip for runway alignment. Trim for the airspeed after setting a constant power. After flaps are constant, use power to adjust touchdown zone in very small reductions.

A good landing begins on a correct downwind being flown. Enter every downwind at the same speed and make speed adjustments on the downwind according to traffic. Use a consistent attitude, airspeed, and power combination. Select flaps according to wind direction and velocity. Once you have leveled off in the flare, use gradual yoke and power changes to maintain a smooth nose-high descent to the touchdown. Keep the nose straight with the rudder and centerline alignment by sideslips. the more consistent you are in your approach configuration settings the better able you will be to make any adjustments or corrections.

Think about keeping the airplane from touching the closer you get to the ground. This will help you keep the nose wheel off the ground and touchdown on the mains. The closer you are to a full stall on touchdown the better the landing and the slower the landing speed. Lift UP on the yoke and hold it all the way up and back until the nose falls by itself.

After a good pattern and stabilized approach comes being trimmed for the speed. Trim, and retrim as required to get and hold the desired speed. If you must apply pressure to hold a speed you MUST make a trim adjustment. If you change power, you must make a related trim adjustment to hold the same hands-off speed.

The Meaning of Stabilized
--Approach is on glide path, at constant descent speed, at constant descent rate and on course.
--The reference speed at short final is based on aircraft about 1.3 of Vso for stall speed and weight.
--POH speeds are all based on gross weights. The Vref and speed on approach will be less. Go figure.
--I Figure that l fly the pattern in ten knot increments ending up at Vref over the numbers. Others use 5 knots.
--I normally fly cruise until abeam the numbers. The losing of this speed sets the pattern size.

Finding the Sweet Spot
The landing is a problem for every new pilot. You have a minute or so to transition from using all the aircraft's energy to keep flying and allow it to dissipate by conversion into loss of altitude and reduction in airspeed. A landing is just another form of flying.

First you must begin and continue to change the configuration and performance to achieve the most controllable and safe approach to the runway. The approach includes the traffic pattern you fly down to just short of the runway You must plan and perform so as to run out of altitude and flying speed at the same instant.

Parallel alignment with the runway is more important than being on the center line. Others disagree on this point . As you approach the runway you look at the end of the runway and the space between it and the nose of your aircraft. You will see the space getting shorter if you are high and longer and flatter if you are low. When the space remains constant you have discovered the one spot where you are going.

Airspeed Control
Landing an aircraft is an exercise in energy control. The major factor in this is control of airspeed. Every phase of the landing process has an airspeed or an airspeed range that provides the maximum safety and utility in the process. I do not teach a range of operational speeds for takeoff, landings, or climb. On downwind, base and final there are a recommended airspeeds. The final approach speed is 1.3 Vso except during gusty conditions. Vso is the calibrated power off stall speed of the aircraft in landing configuration and forward C.G. Vso is calculated on actual landing weight. The POH Vso is calculated on gross weight. The critical Vso on final can be too fast, too slow, adjusted for weight, gusts, and airspeed indicator corrections. I always teach speeds with a margin of operational safety for the student. This margin is not usually revealed to the student.

If you fly an approach at 10% faster than 1.3 Vso, not only will your have a flatter and much longer over the fence, your rollout distance will be twenty percent longer after touchdown all other factors being equal. An approach thirty percent greater than Vso will require 100% additional rollout distance. If you are at a weight less than the maximum gross landing weight you can expect to float longer at Vso before touchdown and hopefully stop in less distance after touchdown because of increased braking efficiency. What this means is that if you have a weight 10% below POH landing gross you should decrease your Vso calibrated airspeed by rule of thumb 5%. This is done because all aircraft stall at slower speeds when they are lighter.

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