Performance Flashcards
Define TODR, take off safety speed, screen height (barrier)
TODR - distance required to takeoff from a standing start at maximum takeoff power and reach a screen height
Takeoff safety speed - speed that gives an adequate margin above the stalling speed. Must not be less than 1.2VS in takeoff configuration.
Screen height - specific height above a runway at the takeoff safety normally 50ft for light aircraft.
Define TODA and clear way and TORA
Takeoff distance available - the length of the takeoff run available plus the length of any clear way.
Clearway - a defined rectangular area on the ground/water at the departure end of the runway selected as a suitable area over which aircraft may make a portion of its climb to a specified height (screen height).
Takeoff run available - the length of the runway declared by the aerodrome operator as available and suitable for aircraft taking off (TORA + clearway)
Define ASDA and stopway
Accelerate-stop distance available - distance specified by appropriate authority as the effective length available for use by an aeroplane executing a rejected take-off. may include a stopway.
Stopway - a rectangular area on the ground at the end of a runway in the direction of the take-off, which is designed as a suitable area in which an aircraft can be stopped in the case of a rejected take-off.
Define gradient and gross and net flight paths
Gradient -
ratio of height gained over a horizontal distance travelled, expressed as a percentage.
Gross -
flight path assumed the aeroplane will follow when flown in a particular configuration.
Established from the aeroplane certification performance data, can be accepted as the average fleet performance for the plane type.
Net flight path -
Gross flight reduced by specific margins which make an allowance for reduced performance that could be expected in an emergency situation in bad conditions.
Landing distance available (LDA), landing distance required (LDR) and landing threshold;
LDA -
Length of runway declared by the aerodrome operate as available for the ground run of an aeroplane.
Landing distance starts at landing threshold and may be displaced.
LDR -
horizontal distance measured from a point 50ft above the runway threshold to a point where the aircraft can be brought to a complete stop with maximum braking.
Landing threshold -
The beginning portion of the runway declared not usable for landing.
Dry, wet, and contaminated (in relation to runway surface); and drift down.
Dry - runway thats neither dry nor contaminated
Wet - runway with sufficient moisture on its surface to cause it to appear reflective but without significant areas of standing water
Contaminated - when more than 25% of runway surface within the required length and width is covered by the surface, slush or snow more than 3mm or ice.
Drift down - a gradual descent by an aeroplane with one engine inoperative to an altitude at which it can comply with the one-engine inoperative en-route climb performance requirements.
Explain factors affecting take-off and landing performance (density, wind, slope, weight, condition, contamination
Air density :
if the ambient air density at an aerodrome is lower than normal, TODR will increase.
Landing performance is affected in poor density conditions. Touchdown speeds (for the same IAS) are higher, for the same amount of braking, thus longer landing distance is required.
Weight: Takeoff distance required will increase with an increase in weight because the acceleration at takeoff power is reduced and the safe lift-off IAS (1.2 VS) is increased.
Landing distances are increased due to the higher weight, as IAS at touchdown will be higher a given amount of braking is less effective in slowing the aeroplane.
Wind: The amount of headwind (or tailwind) affects the take-off and landing distance. Use headwind as in tailwind the landing and take-off distance is increased.
Runway slope: A downslope will decrease the TODR but increase the LDR. Upslope will increase TODR and decrease LDR.
Runway and surface condition: The take-off and landing performance data in an aircraft manual will normally be based on paved level dry runway, any other runway surface, grass metal, rolled earth will result in an increase in TODR or LDR due to reduced braking performance.
Wet or Contaminated runways: When landing on a wet or contaminated runway, there isa requirement to take into account a longer landing distance required due to the reduction in braking performance. In part 135 the LDA must be at least 115% of the LDR calculated for dry conditions
