Frozen brakes and blown tires

Brakes can (and do) freeze up during winter operations. The result may just be embarrassing when you can’t taxi from the run-up area, or onto the runway. It may cause considerable excitement on landing, with a ride through the weeds.
A SA227AC Swearingen taxied onto Runway 27 at Stephenville, NB and waited. The left brake froze while waiting and the pilot was unable to takeoff. There was blowing snow and heavy drifting at the time.
A Cessna 402 landed with a frozen brake and blew the left main tire on Runway 15 at Saskatoon, Sask.
A Piper PA31 Navajo departed Meadow Lake, Sask. with wet wheels and brakes. The pilot left the gear down for a while after takeoff to blow the brakes clean, but the brakes were frozen on landing and both tires blew out.
A Pilatus PC12 landed at Fort Chipewyan, Alta. with frozen brakes and both tires blew out.
A Cessna 172P landed on Runway 09 at Victoria, BC with a flat tire. The pilot was able to keep the aircraft on the runway during the roll out, but was unable to taxi off the runway. The runway was closed for 30 minutes.
Many of us have the bad habit of always taxiing with power at the Aircraft Flight Manual ground idle power setting, about 1,000 rpm. We regulate the taxi speed with the brakes. This heats up the brakes, which will melt any snow that may be packed in around the brake assembly. When the brakes cool while performing a run-up or waiting for takeoff, or after takeoff, the wet snow or water will freeze.
Retractable gear aircraft experience more instances of frozen brakes than do fixed gear aircraft. Water and slush have more opportunity to blow off fixed gear aircraft after take-off. A retractable gear pilot must consciously remember to leave his/her landing gear down for a while after takeoff to blow the gear clean. This is not a guarantee that you will not experience a frozen brake as noted in the incident with the PA31, but it will reduce the chances of a frozen brake.
Twin-engine aircraft and large single engine turboprops such as the Pilatus are even more susceptible to frozen brakes as they have much larger engines and tend to gain speed more rapidly during taxi. Pilots tend to use brakes rather than power to regulate taxi speed.
In any aircraft, in any season, regulate taxi speed with power as much as possible. If power is reduced as soon as the taxi speed is just a little too high, you may not have to use the brakes at all, except to stop. Before any attempt to brake, make sure the power is at the idle stop to reduce the amount of brake required.
In the event that a brake does lock up on landing, use the opposite brake, full opposite rudder, and full opposite aileron to control the swing of the aircraft. This reaction must be very quick in a tail dragger to keep the aircraft from ground looping.
If a brake locks up during taxi, or during a wait before continuing to taxi, be careful how much power you use to get the aircraft moving. There may be other aircraft, people or buildings close behind you.
After taxiing to the parking area in snow, slush or water, do not immediately set the parking brake. It may freeze on.
Tires do occasionally blow right at takeoff. Most Aircraft Flight Manuals have a procedure for landing with a flat tire. The Cessna 172 AFM procedure is:
1. Approach – Normal
2. Touchdown – Good tire first. Hold the airplane off the flat tire as long as possible.
It might be wise to add to this procedure:
Approach with full flap at the airspeed used for a short/soft field landing.
Touchdown as slowly as possible on the side of the runway opposite to the blown tire. The aircraft will swing to the side of the blown tire, so give yourself some extra room.
Pay close attention to the condition of your tires in the winter. It is easy to lock up a brake when braking on a slippery surface and skin a patch of rubber off a tire.
We are all money conscious and we want to get as much out of our tires as possible, but remember the tread is there to help prevent hydroplaning. Hydroplaning can occur on slush as well as on water. The less tread on the tires, the more likely we are to hydroplane, and the more likely we are to blow a tire if we lock up a brake by accident.
Check your brakes and tires before flight. Clean away any snow that may be packed into the brake area. Better yet, check your tires after any landing where you have had braking problems. This will give you time to decide what you are going to do about a worn or skinned tire. If changing the tire is not an option at the moment, you at least know that you should only fly when the runway condition is very good. If such a tire is found just before takeoff, it is less likely you will change it or that you will wait for better conditions.
Think about the conditions you are taxiing in and be aware of the temperatures you will be flying into. Be careful to not heat up the brakes during taxi and remember to blow them off after takeoff if conditions indicate it might be wise to do so. Most instances of frozen brakes and blown tires are preventable.

Dale Nielsen is an ex-Armed Forces pilot, charter pilot and air service operator. He lives in Richmond B.C. where he freelances as an aerial photography pilot and Class 1 flying instructor. Nielsen is also the author of five flight training manuals published by Canuck West Holdings.

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