Cold weather ops Flashcards
With regard to holdover times. Say more about the estimated and actual holdover times?
Estimated holdover times are from the tables. Actual holdover times expire as soon as deposits are seen accumulating on any of the surfaces.
CAUTION:
No holdover times have been established for operations in heavy snow, ice pellets, moderate or heavy freezing rain or hail. If any of these conditions are experienced on the ground after de-icing/anti-icing has been completed, the pre-take-off check is the only method of checking that the aircraft remains free of contamination and must be completed immediately before entering the runway for take-off.
What consideration might you give to taxiing out in freezing conditions?
When taxiing out in freezing precipitation delay the selection of flaps till just prior to entering the runway. (Complete the before take off checks after the procedure)
What would you do if you were landing on a snow or slush covered runway?
Leave flaps extended to be checked by engineering before retracting.
When landing in freezing fog (or fog with OAT at or below 0°C), request a check for (and where present arrange for the removal of) fan blade icing. If no engineering cover call maintrol to ask how this should be done.
When does the holdover time start from when de-icing?
From the beginning of the treatment on a one step and from the beginning of the second treatment with two step.
When is a runway considered to be contaminated?
25% coverage, with either 3mm of slush water, or 10mm of dry snow. Below this not contaminated. Perf manual.
When do you need to add a cold weather correction to the approach altitudes?
In conditions where the surface temperature at an airport is less than ISA -25 deg, pilots should add the values derived from cold weather calculator App to the published procedure altitudes at the Final Approach Fix and the MDA/DA to ensure adequate obstacle clearance.
With respect to cold weather altitude corrections. How should you handle clearances?
IFR clearances may be declined, (on the basis of cold wx)
If they are accepted they should not be altered or adjusted!
When adjustments are made to FAF, ATC should be told how much by.
How do you handle a temperature of less than ISA-25 with regard to RNAV approaches?
If the ambient temperature at an airfield is less than the published temperature shown on the approach chart for an RNAV approach, than pilots should not use VNAV final app mode to fly the vertical profile. Instead the FAF and MDA must be corrected in accordance with the cold wx app.
Fly using VS or flight path angle for the vertical guidance.
