tribo
18th Jan 2011, 16:21
Determine estimated aircraft tire effective braking coefficient µ eff by using the following equations:
µ eff = 0.2 µ max + 0.7 µ max2 (µ max less or equal to 0.7) (4a)
µ eff = 0.7 µ max for µ max (µ max greater than 0.7) (4b)
These relationships between aircraft tire maximum braking and effective braking friction coefficient are based on the assumption that the total aircraft braking-system (tires, brakes, hydraulics, gear and antiskid efficiency can be generated by a single curve 4(a) and (b)
The above is quoted from the report: NASA Technical Paper 2917 - Evaluation of Two Transport Aircraft and Several Ground Test Vehicle Friction Measurements Obtained for Various Runway Surface Types and Conditions - A Summary of Test Results From Joint FAA/NASA Runway Friction Program, February 1990
Aircraft used B727 and B737
How relevant are these equations for todays braking systems (more than 20 years later)?
What level of uncertainty do the assumption tires, brakes, hydraulics, gear and antiskid efficiency can be generated by a single curve represent?
µ eff = 0.2 µ max + 0.7 µ max2 (µ max less or equal to 0.7) (4a)
µ eff = 0.7 µ max for µ max (µ max greater than 0.7) (4b)
These relationships between aircraft tire maximum braking and effective braking friction coefficient are based on the assumption that the total aircraft braking-system (tires, brakes, hydraulics, gear and antiskid efficiency can be generated by a single curve 4(a) and (b)
The above is quoted from the report: NASA Technical Paper 2917 - Evaluation of Two Transport Aircraft and Several Ground Test Vehicle Friction Measurements Obtained for Various Runway Surface Types and Conditions - A Summary of Test Results From Joint FAA/NASA Runway Friction Program, February 1990
Aircraft used B727 and B737
How relevant are these equations for todays braking systems (more than 20 years later)?
What level of uncertainty do the assumption tires, brakes, hydraulics, gear and antiskid efficiency can be generated by a single curve represent?