Advanced Pilot Programs - FS Techniques: Advanced Takeoff and Landing Techniques
Last Updated: March 14th 2006
PART 5: ADVANCED TAKEOFF AND LANDING TECHNIQUES
Soft field, short field and crosswind takeoff and landing techniques are good skills to have in case of an Emergency. If you are proficient at normal takeoffs and landings, then the advance techniques you learn here should be a bite in the dust. Just make sure the only thing you buy afterwards is a cup of coffee, and not the FARM.
Most people will learn these techniques on a regular paved runway and seldom, if ever, get to put their skills to work on a real soft field. However, you will definitely be tested on this as part of the private pilot practical test and, in the event of an emergency landing off airport, you will be glad to have this skill.
To develop your soft field technique, visualize mud. Your objective is to maintain directional control and not get stuck. Before you start your taxi, get organized and complete all necessary pre-takeoff checklists so, that at least in theory, you can keep rolling all the way to the runway and take off without stopping.
In a tricycle gear airplane, taxi with the control wheel held all the way back to minimize weight on the nose wheel. The nose wheel is the most likely to get bogged down, so do what you can to keep it light.
In many airplanes such as the Cessna 152, the soft field takeoff is performed with 10 degrees of flaps extended. In a real soft field situation, tower and traffic permitting, you would taxi onto the runway without stopping and, once lined up on the centerline, apply full power with the control wheel still in the full aft position. You want the nose wheel to come off the ground at the first possible opportunity, but not so swiftly that the airplane rears up and scrapes it's tail on the ground. Most trainers have a tail tie down skid installed to lessen the consequences of scraping the tail. As you add power and accelerate, airflow over the elevator will increase and it will become more effective at raising the nose -- so much so that you will probably need to reduce the backpressure on the control wheel slightly to allow the nose wheel to lift off without the tail scraping. As you add power, you also need to add right rudder to prevent your airplane from unexpectedly exiting the runway to the left due to normal left-turning tendencies that are at their most noticeable in high power/high angle of attack situations.
The idea is to get unstuck from the runway at the first possible opportunity and then build up airspeed before attempting to climb out. So, you accelerate down the runway with the control wheel positioned further back than for a normal takeoff. The nose wheel will lift off first and, as you continue to accelerate and maintain directional control with rudder the main wheels will lift off. This happens at a lower airspeed than for a normal takeoff and below the speed at which it is safe to climb out. As soon as all three wheels are off the ground, move the control wheel forward to lower the nose into a straight and level attitude. This allows the airplane to build up more airspeed before attempting to climb out. Lowering the nose at this point takes some willpower, since it is not intuitive to lower the nose immediately after liftoff when very close to the ground.
It is important, however, that you do not attempt to climb out of ground effect until your airspeed is at least at best rate of climb speed, Vy (will produce greatest gain in altitude in a given time, better visibility over the nose, and better engine cooling). For the purpose of learning/demonstrating your soft field takeoff technique, if the runway environment permits, you may fly along in ground effect a little longer than is strictly necessary. Contrary to what every bone in your body is telling you as you try this the first time, you are unlikely to fly yourself back into the ground unless you are really heavy-handed and not paying attention. You may be heavy-handed but it’s safe to say you’ll definitely be paying attention during this challenging task. Once the desired airspeed is attained, pitch to begin your climb by applying a little backpressure; then climb out at best rate of climb speed, Vy. Once a positive rate of climb is established, retract the flaps and continue the departure as normal.
For a soft field landing, the objective is to land as gently as possible on the main gear and to keep the nose wheel off the ground as long as possible during the rollout to minimize the chances of getting bogged down or flipping the airplane over in severe situations where the nose wheel digs in. Fly a stabilized approach at the recommended speed for the airplane being used and plan on using full flaps. Just before touchdown, add a little power to reduce the sink rate and to provide more elevator authority to help hold the nose wheel off the runway. A power setting just slightly above idle should be sufficient. Touchdown should occur gently in a nose-high attitude. Maintain extra backpressure on the control wheel after touchdown to hold the nose wheel off the runway as long as possible. Don’t overdo the backpressure or you will cause the tail tie-down skid to scrape the ground. You will need to be particularly attentive to rudder input to maintain directional control since you will not have the benefit of nose wheel steering initially. It’s particularly important that the airplane’s longitudinal axis is perfectly aligned with the centerline on touchdown. Eventually, as your speed diminishes, there will be insufficient air flowing over the elevator to maintain the nose-high attitude necessary to keep the nose wheel off the ground. The nose wheel should touch down smoothly while you hold the control wheel full aft to minimize the weight on the nose wheel. Exit the runway with the control wheel held full aft and, local conditions permitting, taxi without stopping to the place you intend to tie down the airplane. Once you stop on a truly soft field, you may have trouble moving again.
Once you master the soft field techniques, you can move on to short field takeoffs and landings. Be careful to distinguish between soft field and short field procedures. They are quite different and not interchangeable
Short field takeoffs are utilized when it is necessary to get off the ground in the minimum distance and climb relatively steeply to clear obstacles. Many trainers such as the Cessna 152 call for use of 10 degrees of flaps for the short field takeoff. Once pre-takeoff checks are complete, set flaps as appropriate prior to taxiing onto the runway. Taxi onto the runway and stop at the very beginning of the runway so no distance is wasted.
While using your toes to apply the brakes and hold the airplane in position gradually add full power. Check the engine instruments and tachometer for normal indications prior to releasing the brakes. In a real short field situation, it’s important to know the airplane is developing full power before attempting to take off with a short runway or obstacles to clear. Hence the run-up to full power prior to brake release. The run-up also prevents wasting runway while you add power. Assuming all indications are normal, release the brakes and accelerate down the runway to rotate as normal and commence a climb out at the recommended obstacle clearance speed or best angle of climb speed, Vx (that speed which gives the most altitude in a given distance, only to clear obstructions). This will be a more nose high attitude than you have used previously and you will need to be attentive to precise airspeed control. Also, because of the high power setting and high angle of attack, (that which the pilot has direct control); you need to use plenty of right rudder to overcome left-turning tendencies. After clearing obstacles, lower the nose slightly and accelerate to best rate of climb speed, Vy. With a positive rate of climb established, retract the flaps and continue the upwind climb as normal.
In a real short field situation, be particularly attentive to maintaining the correct airspeed. Only the recommended obstacle clearance speed, or Vx, will give you the best angle of climb. Anything faster or slower will not work as well. Note: An imaginary line drawn from the leading edge of the wing to the trailing edge called a chord line, the angle between this line and relative wind is called the angle of attack.
The objective of a short field landing is to clear obstacles on final and to land and stop in the minimum distance possible. Landing on a short field and clearing any obstacles on final approach entails setting up a stabilized full-flap approach at the recommended short field approach speed for your airplane. This speed is generally slower than that used on normal approaches and the descent will be steeper than usual, thanks to the lower groundspeed. Once obstacles have been cleared and landing is assured, reduce power to idle and continue to descend at the minimum recommended speed until ready to flare. If your airspeed gets too slow, lower your nose. If you are too low and in danger of not making it to the runway, add some power. Once you are very close to the ground, flare as usual to land main gear first. After touchdown, retract flaps while applying maximum braking. By retracting the flaps, the load is more rapidly transferred from the wings to the wheels, thereby allowing you to brake harder without skidding. Do not allow the wheels to lock up. Bring the airplane to a full stop before exiting the runway.
Because of the greater sink rate associated with short field landings, the touchdown is firmer than for soft field or normal landings. As long as the touchdown is main gear first and there is no bounce, it's acceptable for it to be a bit firm. In windy conditions, it may be appropriate to use a higher approach speed and, under gusty conditions, some pilots prefer to use less than full flaps.
For some pilots, typically those flying old tail draggers, every landing is a no-flap landing. However, even those of us lucky enough to fly airplanes equipped with flaps should learn how to land without using them. In an airplane such as the Cessna 152, a loss of electrical power will prevent you from using the flaps. Also, electric motors that power the flaps sometimes will malfunction.
No-flap landings start with a stabilized approach at the recommended speed for your airplane. Typically, this will be 5-10 knots faster than that used with flaps. In the absence of flaps, your stall speed will be higher, hence the need for a higher final approach speed. Once obstacle clearance and landing is assured, reduce power to idle and flare to touch down as usual.
Because of the higher approach speed, you will use more runway than normal. If you allow your speed to get too fast, you will find your airplane "floating" as you flare, and you could use up a lot of extra runway.
If you find yourself high on final or need to fly a steeper approach to clear obstacles without flaps you can use a forward slip to steepen your descent.
A forward slip is a way of creating extra drag in the absence of flaps as a means of achieving a steeper descent. Forward slips are done with the power at idle. The purpose of the slip is to increase the rate of descent; therefore, to have power applied at the same time would be counterproductive. A forward slip is a descent with one wing lowered using aileron and the longitudinal axis of the airplane yawed at an angle to the flight path using opposite rudder. To initiate a forward slip on final approach, lower one wing using aileron and yaw the longitudinal axis of the airplane in the opposite direction using rudder. If there is crosswind, lower the wing on the side from which the wind is coming. Yaw the nose in the opposite direction to the bank just enough to maintain the desired ground track.
Be attentive to your angle of attack/airspeed while slipping. This is a cross-control maneuver, so it is important to avoid getting too slow or too close to the critical angle of attack. A stall from a slip at final approach altitude would probably develop into an unrecoverable spin.
Because the pitot tube and static ports will not be correctly aligned with the airflow during the slip, you cannot depend on accurate airspeed indications in this configuration. So, be particularly attentive to other indications of getting too slow, such as mushy controls or buffeting. If you get too close to a potential stall speed, lower the nose to increase airspeed and reduce the angle of attack.
Prior to touchdown, it will be necessary to realign the longitudinal axis of the airplane with the runaway centerline. To straighten out prior to flaring, level the wings and release rudder pressure simultaneously to align the longitudinal axis of the airplane with the centerline and then flare to touch down as normal.
Slips are also used in crosswind landings, in which cases asideslip can be used to create a sideways force that is equal to and opposite to the force of the wind drift.
Crosswind Approach and Landing
To land when the wind is not aligned with the runway requires a technique for overcoming the sideways drift that the wind tends to induce. On final approach, this wind drift can be counteracted by either a crab or sideslip. A crab simply entails selecting a heading towards the direction the wind is coming from while flying wings level. The Wind Correction Angle (overcoming side ways drift and the tendency of the airplane to yaw or weathercock into the wind) selected should be enough to prevent drift and maintain a straight ground track along the extended centerline. Adjust the Wind Correction Angle as necessary to achieve zero drift. If you fly your final approach with a crab (crosswind component, example: 90-knot airspeed you will be crabbing approximately ¾ of a degree for each knot of crosswind component), it will be necessary to align the longitudinal axis of the airplane with the runway prior to touchdown. This alignment needs to be made just prior to touchdown. It requires precise timing to avoid drifting if the crab is terminated too soon or landing out of alignment with the centerline if you leave it too late. The landing gear is not designed to handle side loads, so it is very important that the airplane be longitudinally aligned with the centerline and not drifting on touchdown.
The alternative to the crabbed approach and last minute correction is to use a sideslip to counteract wind drift. This can be done for the whole final approach or just for the last part after starting out using a crab. The idea is to lower the wing on the side from which the wind is coming, using aileron to counteract wind drift, and to use opposite rudder to maintain longitudinal alignment with the centerline. The extent to which the wing is lowered will depend on the force of the wind. If you get to the point where to counteract wind drift you need to lower the upwind wing so much that full opposite rudder is insufficient to maintain alignment with the runway, it means the wind is too strong for a safe landing and you should select an alternate runway with less crosswind.
During the flare, you need to maintain wing low crosswind correction to avoid drifting and, in strong crosswinds, this means the main wheel on the side of the airplane from which the wind is coming (upwind) will touch down momentarily before the other wheel does. Once on the ground, be sure to follow through with control inputs to counteract the wind. That is, position the control wheel as if turning the airplane into the wind, using full deflection of the ailerons. At slower speeds, it takes bigger deflections of the control surfaces to have an effect. Use the rudder to maintain directional control during the rollout.
Crosswind landings are challenging, and it will take considerable practice to master these techniques. During your solo training, you can expect your instructor to place limitations on your solo privileges based on a maximum crosswind component.
Better to use your superior judgment to select a runway aligned with the wind than to count on using superior skill to land in a strong crosswind. Just be sure your airplane is capable of handling the crosswind components.
NOTAM Pilots VA world only: places to have fun with short field takeoffs and landings in FS2002, FS2004 flight sim world, any location with runway length from 2500-5000 ft, with aircraft from Cessna 172-Airbus 380… I included the 380, because I discovered that my 11 year old daughter, who is also an accomplished Flightsimer, and very proficient in FS 5.0, 2000, 2002 and 2004 performed a short runway take off at BGSS in Greenland with the 380. I hate to admit this, but she is a better Helicopter pilot than I.
A Good Cross Wind Procedure, Real World and VA world:
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