Chapter 6 - Aircraft Critical Surface Contamination Examination Questions

2.0  Theory and Aircraft Performance

2.01  Aircraft certified for flight in known icing conditions have been designed and have demonstrated system capability of providing adequate protection against the adverse effects of airframe icing

  1. both in flight and on the ground.
  2. in flight only.
  3. on the ground only.
  4. under all inflight icing conditions.

2.02  Stall warning systems are calibrated to give an effective warning

  1. in icing conditions if all components are heated.
  2. in icing conditions when the backplate is heated.
  3. under all conditions.
  4. under clean wing conditions.

2.03  Aircraft performance may be seriously affected by frost, ice or snow on the wings and control surfaces primarily because of the

  1. increase in gross weight.
  2. disruption of smooth airflow.
  3. strong possibility that the control hinges will freeze.
  4. adverse movement of the C of G.

2.04  Frost, ice or snow on a wing will

  1. increase the stall speed but will not affect the rate of climb.
  2. decrease the stall speed and reduce the rate of climb.
  3. increase the stall speed and reduce the rate of climb.
  4. not affect the stall speed or the rate of climb.

2.05  Contamination on an aircraft wing is dangerous primarily because

  1. the aircraft may become airborne in ground effect but be unable to climb.
  2. drag will prevent the aircraft accelerating to take off speed.
  3. its weight will cause the centre of pressure to move forward and reduce the rate of climb.
  4. of all of the above factors.

2.06  Frost, ice or snow formation on the leading edge and upper surface of a wing, having a thickness and surface roughness similar to medium or coarse sandpaper, can reduce the wing lift by as much as ... and increase drag by as much as ...

  1. 10%, 20%.
  2. 30%, 40%.
  3. 50%, 75%.
  4. 75%, 100%.

2.07  The adverse effects of frost, ice or snow on aircraft include

  1. decreased thrust and lift, and increased drag and stall speed.
  2. trim changes and altered stall characteristics.
  3. altered handling qualities.
  4. all of the above.

2.08  Frost, ice or snow on an aircraft may

  1. increase the stall speed but the stall characteristics remain the same.
  2. increase the drag but take off acceleration remains unaltered.
  3. decrease the lift and alter stall and handling characteristics.
  4. decrease thrust and stall speed.

2.09  A significant part of the loss of wing lift can be attributed to

  1. under wing contamination.
  2. leading edge contamination.
  3. flap contamination.
  4. trailing edge contamination.

2.10  The use of SAE Types II and IV fluids on large aircraft

  1. will not cause any performance degradation or require weight or other take off compensation.
  2. will require weight and take off compensation for all those with a Vr of 100 kt and below.
  3. should be restricted to those with a Vr above 100 kt.
  4. should be restricted to those with a Vr above 85 kt.

2.11  The use of SAE Types II and IV fluids could cause significant performance degradation for aeroplanes with rotation speeds

  1. of 85 kt to 100 kt only.
  2. of 85 kt and below only.
  3. above 100 kt.
  4. of 100 kt and below.

2.12  One of the key determinants in using anti icing fluids on a particular aeroplane is the

  1. time taken to accelerate to Vr.
  2. time taken to accelerate to V1.
  3. distance travelled to accelerate to V2min.
  4. distance travelled to accelerate to V3.

2.13  Who should determine what effect SAE Types II and IV fluid dryout, remaining on the aircraft, will have on aircraft performance or handling qualities during flight?

  1. The fluid manufacturer.
  2. The aircraft manufacturer.
  3. The aircraft operator.
  4. The deicing contractor.

2.14  Undiluted propylene glycol, having a strength of about 88% glycol, at temperatures less than 10°C has been found to cause lift reductions of about

  1. 10%.
  2. 20%.
  3. 30%.
  4. 40%.

2.15  Frost and ice could form or snow could adhere to the surface of an aircraft if its skin temperature is

  1. at or below freezing and the surrounding air is above freezing.
  2. below freezing and the surrounding air is cool and humid.
  3. at or below freezing and the surrounding air is well below freezing.
  4. all of the above.

2.16  After extended flight at a temperature of -20°C, an aircraft arrives for a quick turn around at an aerodrome where the temperature and dew point are 10°C and 9°C respectively. The pilot could expect

  1. blockage of the fuel vent system.
  2. ice formation over the entire wing surface.
  3. no adverse problems.
  4. frost to form in the area of the wing fuel tanks.

2.17  An aircraft which has been de iced in a heated hanger is rolled out into sub zero temperatures. The pilot should be particularly alert for

  1. freezing of wet surfaces or pooled water.
  2. frost formation.
  3. sublimation of water vapour into ice crystals.
  4. all of the above.

2.18  When aircraft are operating on slush or wet surfaces, ground crew should be particularly alert for contamination of

  1. the wheel wells.
  2. the underside of the aircraft.
  3. the control surfaces.
  4. all of the above.

2.19  An aircraft is refuelled with sub zero temperature fuel in conditions of high humidity. The pilot could expect

  1. clear ice to form around integral fuel cells.
  2. frost to form around integral fuel cells.
  3. no icing or frost problems.
  4. frost to form around integral fuel cells only if the ambient air temperature is below zero.

2.20  After extended flight at a temperature of -20°C, an aircraft arrives for a quick turn around at an aerodrome where there is light drizzle with a temperature of +8°C. The pilot could expect

  1. no adverse problems.
  2. ice to form on top of the wing in the area of the fuel tanks.
  3. frost to form on top of the wing in the area of the fuel tanks.
  4. ice to form on the bottom of the wing and frost to form on the top.

2.21  When an aircraft that has experienced frost formation on the wing because of the cold soaking phenomenon is de iced,

  1. the maximum holdover table values are applicable.
  2. the frost tends to reform quickly, even when removed.
  3. no further deicing will be required.
  4. the minimum holdover table values are applicable.

2.22  A very critical cold soaking phenomenon situation arises at aerodromes where there is

  1. drizzle with an ambient temperature around +15°C.
  2. rain with an aircraft skin temperature of +8°C.
  3. dry snow with an aircraft skin temperature between +8°C and +14°C.
  4. wet snow with an ambient temperature around 0°C.
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