Adverse WX Limitations

Question 1

Definition of icing conditions?

Answer 1

• SAT on ground and for takeoff is 10C or below or SAT in flight is 5C or below and visible moisture in any form is present. (Such as clouds, fog with visibility of one mile or less, rain, snow, sleet or ice crystals).
• Icing conditions also exist when the SAT on the ground and for takeoff is 10C or below when operating on ramps, taxiways or runways where surface snow, ice, standing water, or slush may be ingested by the engines or freeze on engines, nacelles or engine sensor probes.
• Icing conditions are considered to exist at takeoff where visible moisture (cloud ceiling) is present at 1,000’ AGL or below at a SAT of 5C or less.

Question 2

Definition of icing conditions in flight:

Answer 2

• 5C or below
• visible moisture in any form

Note: ice accretion on aerodynamic surfaces is not considered to exist at temps of -40C or below.

Question 3

Maximum ambient temp limitation with engine bypass doors open using MTOP and MCP?

Answer 3

ISA +25C

Question 4

CAT II Limitations:

Answer 4

• flap 35 not authorized
• Dual FD’s by 1,100’ rad alt (latest)
• pilot monitored approach with autopilot engaged (captain flys)
• landing configuration prior to FAF
• max x-wind 18kts, max TW 10kts, max HW 24 kts
• ## max glideslope angle of 3.5 degrees

Question 5

Takeoff is not approved (Supp 37) on runways covered by more than:

Answer 5

• 12.7 millimeters (0.50 inch) of standing water;
• 12.7 millimeters (0.50 inch) of slush;
• 18.0 millimeters (0.75 inch) of wet snow; or
• 50 millimeters (2.00 inches) of dry snow.

Question 6

When Icing is detected…

Answer 6

• the AIRFRAME MODE SELECT switch must be positioned FAST or SLOW
• the wing and tail leading edge de-Icing boots shall be activated at the first sign of ice formation anywhere on the aircraft.
• the system shall be operated in automatic cycling mode if available, or manually cycled as needed to minimize ice accumulation
• The boots may be deactivated only after completion of two complete de-Icing cycles after leaving Icing conditions

Question 7

In severe Icing, what actions must be taken?

Answer 7

• Autopilot must be disengaged
• set condition levers to max
• Exit Icing conditions asap

Question 8

What constitutes a contaminated runway?

Answer 8

• A runway is considered to be contaminated when more than 25% of the runway surface area, within the required length and width being used, is covered by surface water, slush or loose snow. Equivalent of TALPA codes 2 and 3.
• A runway is considered to be contaminated when 100% of the runway surface area, within the required length and width being used, is covered by compacted snow, which resists further compression. Equivalent to TALPA code 4.
• Wet runway with standing water >0.125 inch of standing water is equivalent to TALPA code 5
• A runway is considered to be contaminated when more than 25% of the required length and width being used, is covered by wet ice, and braking effectiveness is expected to be very low. If CRFI is reported to be .4 or better, it is acceptable to use compact snow contaminant data. Equivalent of TALPA code 0 or 1. If TALPA code is reported 0, takeoffs and landings are prohibited.

Question 9

What is the required length and width being used, for the purpose of determining if the runway is contaminated or not?

Answer 9

• Landing, Width of 100’ and the demonstrated landing distance based on the conditions.
• Takeoff, width 100’ and runway length entered in data.

Question 10

What contamination factor do you use when the runway is 100% frost?

Answer 10

Compact Snow