De-Ice Flashcards
You suspect icing conditions prior to departure. What do you do?
Conduct Cold WX Preflight Inspection
When:
- OAT 5°c or less
- wing fuel temp 0°c or less
- atmospheric icing conditions
- frozen contaminants, frost or precip adhering to airframe
- residual, accumulated ice from inbound flight
- cold soaked ice in fuel tank
What is a Cold WX Preflight inspection?
GDPM 4-5/6
Visual inspection conducted during the external walkaround prior to departure by a crew member to determine the wing and critical surfaces are free of frozen contaminants.
What temperatures are conducive to icing?
GDPM 4-3
Conditions conducive to icing may occur when OAT is at or below 10°c and:
- visible moisture present
- moisture on wing
- wing fuel temp is 0°c or less, OAT 3°c or less
- atmosphere conducive to frost formation
- water, snow, ice on ramp, rwy, taxiway
What’s the maximum frost that may adhere to the aircraft for departure?
GDPM 4-6
ERJ - maximum 1/8in underwing fuel tank area caused by cold soaked.
TO permitted with frost on upper surface of fuselage as long as distinguishing surface features can be determined.
What is a critical surface?
Surfaces that must be free of frozen contaminants prior to takeoff so that performance is not compromised.
Wings, tail, engine nacelle
Why do we not want to depart with frozen contaminants adhering to critical surfaces on an aircraft?
Degradation in performance:
- severe loss of lift, 30% decrease
- increased drag, 40% increase
- impaired aerodynamic airflow
- impaired maneuverability during critical phases of flight
- increased stall speed. Easier to stall
- increased weight
- impaired sensors.
- Inaccurate flight data
- power loss, engine damage
- impaired mechanical performance: landing gear, flaps, flights controls
Who haste final ultimate responsibility to determine if an aircraft is in a condition safe for flight?
PIC,
However, all crew members, deice personnel and other operations personnel are jointly responsible to prevent frozen contamination from adhering to aircraft.
What do you do if it’s determined the aircrafts critical surfaces are not free of frozen contaminants?
GDPM 4-5
PIC notify station personnel that ground de-icing is required
What if you can’t determine that the critical surfaces are free from frozen contaminates?
GDPM 4-5
PIC notify station personnel ground de-ice is required
What if you determine the critical surfaces are free from frozen contamination?
GDPM 4-6
After completing a visual and TACTILE check, no further deice/anti-ice precedures are required.
What’s the difference between de-ice and anti-ice?
GDPM 4-6
De-ice: 1 step process used to remove frozen contaminants from aircraft
- deicing procedures must be performed anytime frozen contaminants are adhering to any critical surface of aircraft.
Anti-ice: 2 step method used to provide protection against the formation of frozen contaminants on clean surfaces of the aircraft once the aircraft has been de-iced.
- anti-ice procedures are performed only when it is determined that an extended holdover time is required in order to prevent the accumulation of frozen contaminants on the critical surfaces prior to take-off.
When does a holdover time begin?
GDPM 4-7
Holdover time begins when the final application of the de-ice/anti-ice fluid is first applied to the aircraft.
What’s a Post de-ice check?
Visual inspection of aircrafts critical surfaces for frozen contamination during de-ice fluid application completed by De-ice personnel.
What is the PreTakeoff contamination Check Procedure?
GDPM 4-16
- Check performed by the flight deck crew prior to takeoff.
- must be performed anytime the aircraft has been de-iced/anti-iced, and a HOT time has been established, to ensure the critical surfaces are remain free of frozen contaminants.
- performed within the HOT time, anytime as close to takeoff as possible. Take-off must occur within 5 minutes if check.
- conducted from whatever vantage point PIC determines gives an accurate indication of representative/critical surfaces. (Flight deck/cabin)
What do you do if ice is still adhering, you can’t tell if it’s adhering, you suspect the fluid has failed or HOT time is exceeded?
GDPM 4-16
Repeat the process. Aircraft must be de-iced/anti-iced again.
Critical surfaces MUST be free of contaminants.
You may exceed a HOT time as long as it’s no longer valid do to changed weather. Meaning it cleared up and there’s no ice on critical surfaces.
