|
There are three types of slips , the forward slip, the turning and the side slip. Of the three the FAA expects you to know and be proficient in forward and side slips. In Canada they do three types of slips for the flight test. (More)
Forward Slip
Increases rate of descent without increasing airspeed. This is an essential skill for losing excess altitude in aircraft and can usually be accomplished in any flap configuration. When performing the forward slip the longitudinal axis is at an angle to descent path. The side of the aircraft increases drag and gives higher rate of descent with the engine idling. You want to lose altitude without building up speed. The maneuver is best accomplished by lowering the upwind wing and at the same time applying opposite rudder. In unison the two controls are used to keep the plane's line of descent aligned with the runway. The plane's heading will veer towards the lowered wing so compensating rudder is used to maintain the desired descent line. Side Slip
The primary use of the side slip is to establish and maintain alignment with runway in crosswind. The aircraft longitudinal axis is kept parallel with runway centerline. With change in altitude the crosswind effect varies so that the combined use of rudder and aileron are used to slide the aircraft side to side to counteract any crosswind changes. Parallel alignment is kept with the rudder while variations of bank angle are used to compensate for changes in crosswind effect. By lowering the upwind wing into the wind and using enough opposite rudder to maintain runway alignment very small adjustments will be needed. This particular slip requires very uncoordinated use of both the rudder and aileron. This segment of the slip is best practiced by doing Dutch rolls. If you need to think of what you are doing you won't do it easily or correctly. If you run out of rudder authority needed to keep the plane aligned with the runway you can increase the airspeed as required. At some point you may not be able to keep the nose aligned and centered. Go around and go elsewhere. You have exceeded your piloting skills and are probably exceeding the crosswind capabilities of the plane as well. Turning Slip
The slipping turn is a slip performed while turning. The desired turning path and rate of descent can be easily controlled through uncoordinated use of rudder and aileron. The slipping turn is an additional landing tool to be used in descending and arriving at a specific point prior to roundout, flare, and touchdown.
It is commonly used at unfamiliar small airports where poor visual factors or obstructions make it necessary to lose excess altitude. Landing in this type of situation can be practiced at large airports by requesting a short approach at every opportunity. This is especially important for IFR trainees out of the-circle-to-land approach.
A stall in a slipping turn will cause the high wing to drop quickly, this will simultaneously stop both the turn and the stall. The stall occurring in a skid will aggravate both the stall and the turn while entering a spin. Remember: ---Watch your local airport landings, fewer than 30% land in the first third of the runway.
---When fast and high, slow down and slip power off into the prevailing wind for losing height.
---Slips are a more precise means of reducing energy.
---Slips are controlled and controllable uncoordinated turns
---Slips and non-use/misuse of them are in the top two reasons for checkride failures.
---The forward slip is used to lose altitude by using the side of plane to produce drag.
---Altitude loss is determined by wind velocity and direction, airspeed, bank and rudder authority.
---The drag produced by a slip is both variable and controllable.
---Use of power in a forward slip is counter productive to losing altitude.
---Use of power in a side slip increases rudder authority.
---The side slip is to correct for crosswind drift correction.
---You do not know how to side slip if you must think about how and what to do.
---Cessnas may oscillate under certain conditions of slips with flaps. Read the POH.
---Prolonged slips may cause tank fuel pickups to un-port under certain low fuel conditions.
---Safety of a slip lies in the fact that at lower speeds a stall will first occur and drop the higher wing.
---Holding the rudder in a stall derived from a slip will result in an over-the-top spin entry.
---Relaxing the rudder in a stall derived from a slip will result in an immediate recovery from the stall.
---In a skid the low wing stalls first and gives an immediate spin entry.
---The slip is an additional tool in controlling a stable descent other than power and airspeed.
---Running out of rudder is the limiting slip control.
---The slip is one the best options for losing altitude in an emergency employed as with flaps or turning.
---The slip is not as fast as is a steep bank in a diving turn for losing altitude in a hurry. Use flaps, too.
---The slip is instantly recoverable but a smoother release of rudder is more comfortable.
---Slips into the static port gives a false high airspeed, away gives false low airspeed.
---Extreme and prolonged slips are uncomfortable to those not performing the slip.
---Improper use of slips is the second most common reason for flight test failures. The first are precision landings. |
