US7963620B2 - Carbon brake wear for aircraft - Google Patents
Because the wear mechanisms are different between carbon and steel brakes, different taxi braking techniques are recommended for carbon brakes in order to maximize brake life.
Carbon Brakes and Slush - SKYbrary Aviation Safety
Using truck 44 as an example, wheels 52 and 54 on one side, and 56 and 58 on the other side of a four-wheel axle frame 60 each provide input to a brake disable circuit 62 like that described in FIG. By braking harder, you are spending less time on the brakes in total, which means that you will have less wear on the brakes.
For example, brakes on wheels 52 and 54 on the left side of the truck 60 would be alternately disabled during successive brake applications as would the brakes on wheels 56 and GBA en. Similarly, if a higher speed stop, such as a landing stop or rejected take off, is sensed by brake disable circuit 24 from the aircraft speed signal, then the brake release logic 32 removes the brake release command so that both brakes 6 and 8 may share the braking energy, preventing overheating of an individual brake or brakes.
While the invention has been described in terms of specific embodiments thereof, other forms may be readily adapted by one skilled in the art. Subsequently, comparison is continuously made inside brake release logic 32 between the metered pressure signal value and a second predetermined value.
I don't think it flows really well as an edit to my answer, so I've removed it for now.
An alternating wheel braking pattern is established to minimize brake wear at each braked wheel and yet to promote even distribution of absorbed energy among all the brakes.
While carbon brakes are preferred for weight and performance reasons over steel brakes, the cost of replacing the stack divided by the number of landing cycles between replacements is much higher than for steel brakes. That is, if heavy braking intensity is called for, all the brakes are applied. All recommended braking techniques should aim at reducing the number of brake applications and optimizing the carbon brake temperature. Carbon friction increases as brake gets hotter vs.
Carbon composite rotors are connected to the wheel through the rotor drive keys and turn with the wheel. By far the largest number of brake applications occur during ordinary taxiing, so in preferred embodiments of this invention, only some of the brakes are applied in response to brake applications under ordinary taxiing conditions.
How to get the most out of Carbon Brakes Air Transport Safety Articles by Shem Malmquist
Context switching system for a multi-thread execution pipeline loop and method of operation thereof. SKYbrary Content control: As indicated by bipolar knife switch 36 , only one of the two antiskid valves 20 and 22 will be commanded to release its respective brake through left diode 38 or right diode 40 when brake release logic 32 triggers.
Automatic control system for directional control of an aircraft during landing rollout. However, systems in accordance with this invention for aircraft with other numbers and arrangements of carbon braked wheels could be readily adapted by persons skilled in the art.
A metered brake pressure signal would also be provided to each like brake disable circuit.
Laminate of metal sheets and wires connected thereto, as well as methods of manufacturing the same. A simplified example of a preferred embodiment of this invention is shown schematically in FIG.
Methods and systems for controlling wheel brakes on aircraft and other vehicles. Maximum steel brake life can be achieved during taxi by using a large number of small, light brake applications, allowing some time for brake cooling between applications. If an emergency stop, i. From gate departure to takeoff — traffic conditions permitting, minimize frequency of taxi brake applications: This invention relates to a method and means for increasing the life of carbon aircraft brakes.
If you wish to contribute or participate in the discussions about articles you are invited to join SKYbrary as a registered user. Systems and methods for braking aircraft, including braking intermediate main gears and differential braking. Normal stop wear: Carbon brake wear is primarily dependent on the total number of brake applications — one firm brake application causes less wear than several light applications.
For example, brakes on wheels 52 and 54 on the left side of the truck 60 would be alternately disabled during successive brake applications as would the brakes on wheels 56 and The speeds of wheels 2 and 4 are sensed through sensors 12 and 14 and processed in antiskid control circuit 10 to determine aircraft speed.