Blown tires
Blown tires during landing are sometimes caused by frozen brake stacks during flights in cold weather conditions. In most situations when this has happened, the brakes did not incur any damage and were not covered under warranty if replaced.
Each of the model Flight Manuals provide instructions to snub the brakes during taxi operations in freezing conditions with moisture present. It is also important to remember to cover wheel and brake assemblies when washing the aircraft. Operators can refer to the procedures outlined in the respective maintenance manuals; offering instructions on how to place covers on all airplane tires, brake assemblies, and wheel assemblies when the aircraft is being washed.
CAUTION: Do not pressure-wash the wheels or brakes. The carbon disks in the brake assemblies must be kept dry. Degradation of the carbon properties and possible freezing of the brake assemblies may occur when carbon is exposed to water.
PREFLIGHT INSPECTION – EXTERIOR
In addition to AFM Normal Procedures, make sure the wheels are not frozen to the ground surface, and verify ice has not accumulated on the landing gear brake stacks
If the airplane is stored in a hangar to defrost, water may collect in the brake components and freeze in flight. Frozen brakes may not allow the tires to rotate after landing and blown tires may result.
If the aircraft is left outside in cold climate with wet brakes, Cessna recommends rinsing the brake stack outer perimeter with denatured/anhydrous isopropyl alcohol, with the parking brake off. Alcohol may be applied before or after flight when the brakes are cool enough to touch but not below freezing
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BEFORE TAXI
Before taxiing through slush, ice, or water, leave the flaps up until completing the before takeoff checklist. This practice will help prevent ice contamination on flap surfaces.
. Before applying anti-ice fluid to the aircraft before takeoff, Cessna recommends that operators complete the Before Takeoff Anti-ice Systems – CHECK item in the AFM.
TAXI
Nose Wheel Steering – Verify nose wheel controllability in both directions. Avoid tight turns with brake application and large steering changes on icy surfaces as loss of steering control may be experienced.
Thrust Reversers – Reverse thrust should be used if necessary when the taxi surface is slippery or cov-ered with slush or snow. Reverse thrust can cause surface contaminants to become airborne and freeze on the aircraft lifting surfaces. Nose wheel skidding may result, especially with single reverser operation.
Adequate Aircraft Separation – Stopping distances will be longer on contaminated runways.
Brake Stacks – HEAT within the last mile of taxi to remove excess water that may freeze after takeoff. This is important if the taxi was through wet or slushy surfaces. Operators should refer to their applicable AFM procedures for brake application and stopping distance considerations.
AFTER TAKEOFF
If conditions permit, consider leaving the gear down to 200 KIAS prior to retraction to help clear moisture and slush from the gear assemblies. After landing on ice or slush, a complete check of the airplane, including overboard vents, brakes, and control surfaces should be conducted.
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