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An ice protection system for a structure has at least one electro-thermal heating element carried by the structure and a controller for selectively controlling the operation of each heating element. The controller operates each heating element according to a selected duty cycle defined by a pattern

An ice protection system for a structure has at least one electro-thermal heating element carried by the structure and a controller for selectively controlling the operation of each heating element. The controller operates each heating element according to a selected duty cycle defined by a pattern of time intervals, the controller selecting the duty cycle at least partially in response to measurements of ambient conditions about the structure.

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1. An ice management system for a structure, the system comprising: at least one electro-thermal heating element carried by the structure for heating a heated portion of the structure; anda controller for selectively controlling the operation of each heating element, the controller being configured

1. An ice management system for a structure, the system comprising: at least one electro-thermal heating element carried by the structure for heating a heated portion of the structure; anda controller for selectively controlling the operation of each heating element, the controller being configured to selectively adjust a control temperature band, the control temperature band comprising an upper control temperature and a lower control temperature;wherein the controller is further configured to repeatedly adjust the upper control temperature and the lower control temperature of the control temperature band at least partially in response to sensed changes of an air temperature near the structure and a velocity of air passing over the structure;wherein the controller is further configured to operate each heating element according to a selected duty cycle defined by a pattern of time intervals;wherein, for each time interval in the duty cycle, the controller is further configured to predict the temperature of the heated portion of the structure at the end of a next time interval to determine whether to apply an on or off condition during the next time interval, thereby operating each heating element so as to obtain and maintain a temperature of the heated portion of the structure approximately within the control temperature band; andwherein the prediction of the temperature of the heated portion of the structure at the end of the next time interval is based on an expected rate of change of a temperature of the structure were the at least one electro-thermal heating element to be operated in the subsequent time interval. 2. The system according to claim 1, wherein each time interval is a pre-determined length. 3. The system according to claim 1, wherein the time intervals are of equal length. 4. The system according to claim 1, wherein each time interval is about 250 milliseconds. 5. The system according to claim 1, wherein the controller operates to adjust the duty cycle according to at least one measurement of the air temperature near the structure, and the velocity of air passing over the structure. 6. The system according to claim 1, further comprising: at least one temperature sensor carried by the structure for sensing a temperature of a portion of the heated portion;wherein the controller selects the duty cycle at least partially in response to an output of the at least one temperature sensor. 7. The system according to claim 1, further comprising: at least one ice detection sensor;wherein the controller selects the duty cycle at least partially in response to an output of the at least one ice detection sensor. 8. The system according to claim 1, wherein the controller selects the duty cycle so as to prevent the temperature of the heated portion of the structure from increasing faster than a predetermined maximum rate. 9. The system according to claim 1, wherein the structure is a thin material. 10. The system according to claim 1, wherein the structure is a radome adapted for enclosing a radar system. 11. The system according to claim 1, wherein each heating element is configured to allow transmission of at least a selected frequency of electromagnetic energy through the structure. 12. An ice management system for a radome having at least one surface exposed to atmospheric conditions, the system comprising: at least one electro-thermal heating element carried by the radome for heating an adjacent portion of the exposed surface; anda controller for selectively controlling the operation of each heating element, the controller being configured to selectively adjust a control temperature band, the control temperature band comprising an upper control temperature and a lower control temperature;wherein the controller is further configured to repeatedly adjust the upper control temperature and the lower control temperature of the control temperature band at least partially in response to sensed changes of an air temperature near the structure and a velocity of air passing over the structure;wherein the controller is further configured to operate each heating element according to a selected duty cycle defined by a pattern of time intervals; andwherein, for each time interval in the duty cycle, the controller is further configured to predict the temperature of the heated portion of the structure at the end of a next time interval to determine whether to apply an on or off condition during the next time interval, thereby operating each heating element so as to obtain and maintain a temperature of the heated portion of the structure approximately within the control temperature band; andwherein the prediction of the temperature of the heated portion of the structure at the end of the next time interval is based on an expected rate of change of a temperature of the structure were the at least one electro-thermal heating element to be operated in the subsequent time interval. 13. The system according to claim 12, wherein each time interval has a pre-determined length. 14. The system according to claim 12, wherein the time intervals are of equal length. 15. The system according to claim 12, wherein each time interval is about 250 milliseconds. 16. The system according to claim 12, wherein the controller operates to adjust the duty cycle according to at least one measurement of the air temperature near the structure, and the velocity of air passing over the structure. 17. The system according to claim 12, further comprising: at least one temperature sensor carried by the radome for sensing a temperature of a portion of the radome;wherein the controller selects the duty cycle at least partially in response to an output of the at least one temperature sensor. 18. The system according to claim 12, further comprising: at least one ice detection sensor;wherein the controller selects the duty cycle at least partially in response to an output of the at least one ice detection sensor. 19. The system according to claim 12, wherein the controller selects the duty cycle so as to prevent the temperature of the heated portion of the structure from increasing faster than a predetermined maximum rate. 20. The system according to claim 12, wherein each heating element is configured to allow transmission of at least a selected frequency of electromagnetic energy through the radome. 21. The system according to claim 12, wherein the radome is constructed of a thin material. 22. An aircraft, comprising: a fuselage;a means for producing lift;a radar system;a radome for enclosing at least a portion of the radar system;at least one electro-thermal heating element carried by the radome for heating an adjacent portion of the radome;a controller for selectively controlling the operation of each heating element, the controller being configured to selectively adjust a control temperature band, the control temperature band comprising an upper control temperature and a lower control temperature;wherein the controller is further configured to repeatedly adjust the upper control temperature and the lower control temperature of the control temperature band at least partially in response to sensed changes of an air temperature near the structure and a velocity of air passing over the structure; andwherein the controller is further configured to operate each heating element according to a selected duty cycle defined by a pattern of time intervals;wherein, for each time interval in the duty cycle, the controller is further configured to predict the temperature of the heated portion of the structure at the end of a next time interval to determine whether to apply an on or off condition during the next time interval, thereby operating each heating element so as to obtain and maintain a temperature of the heated portion of the structure approximately within the control temperature band; andwherein the prediction of the temperature of the heated portion of the structure at the end of the next time interval is based on an expected rate of change of a temperature of the structure were the at least one electro-thermal heating element to be operated in the subsequent time interval. 23. The system according to claim 22, wherein the controller operates to adjust the duty cycle according to at least one measurement of the air temperature near the structure, and the velocity of air passing over the structure. 24. The system according to claim 22, further comprising: at least one temperature sensor carried by the radome for sensing a temperature of a portion of the radome;wherein the controller selects the duty cycle at least partially in response to an output of the at least one temperature sensor. 25. The system according to claim 22, wherein the controller selects the duty cycle so as to prevent the temperature of the heated portion of the structure from increasing faster than a predetermined maximum rate. 26. The system according to claim 22, wherein each heating element is configured to allow transmission of at least a selected frequency of electromagnetic energy through the radome. 27. The system according to claim 22, wherein the radome is constructed of a thin material. 28. A method for controlling a heater carried on a structure for managing ice formation on the structure, the method comprising: sensing an air temperature near the structure and a velocity of air passing over the structure;automatically and repeatedly adjusting an upper control temperature and a lower control temperature of a control temperature band based upon changes in the sensed air temperature near the structure and the velocity of air passing over the structure, the control temperature band representing a desired temperature range of the structure;automatically selecting a duty cycle for operation of the heater, the duty cycle being defined by a pattern of time intervals, in which electrical power is supplied or not supplied to the heater for the duration of each time interval within the pattern, the selection of the duty cycle being at least partially in response to the sensed air temperature near the structure and the velocity of air passing over the structure; andfor each time interval in the duty cycle, automatically predicting the temperature of the heated portion of the structure at the end of a next time interval to determine whether to apply an on or off condition during the next time interval, thereby operating the heater so that a temperature of the structure approximately resides below the upper control temperature and above the lower control temperature; andwherein the predicting of the temperature of the heated portion of the structure at the end of the next time interval is based on an expected rate of change of a temperature of the structure were the heater to be operated in the subsequent time interval. 29. The method according to claim 28, wherein each time interval is a pre-determined length. 30. The method according to claim 28, wherein the time intervals are of equal length. 31. The method according to claim 28, further comprising: sensing a temperature of at least a portion of the structure; andwherein the selection of the duty cycle is at least partially in response to the sensed temperature. 32. The method according to claim 28, wherein the duty cycle is selected so as to prevent the temperature of the structure from increasing faster than a predetermined maximum rate. 33. The method according to claim 32, wherein the heater is automatically switched off when the temperature of the structure reaches an upper limit of the control temperature band. 34. The method according to claim 32, wherein the heater is automatically switched on, with a selected duty cycle, when the temperature of the structure reaches a lower limit of the control temperature band. 35. A method for controlling a heater carried on a structure, the method comprising: operating the heater according to a selected duty cycle, the duty cycle being defined by a pattern of time intervals, electrical power being supplied or not supplied to the heater for the duration of each time interval within the pattern;for each time interval in the duty cycle, calculating a predicted temperature of the structure near an end of the subsequent time interval, the calculation being based on a current temperature measurement of the structure, a measured rate of change of temperature of the structure during a recent time interval so as to provide an expected rate of change of temperature were the heater to be operated in the subsequent time interval according to the duty cycle, and a measured rate of change of temperature of the structure during a recent time interval so as to provide an expected rate of change of temperature were the heater not operated in the subsequent time interval according to the duty cycle; andsensing whether at least one of airspeed and outside air temperature has changed;adjusting an upper control temperature and a lower control temperature if a change is sensed in at least one of airspeed and outside air temperature;automatically supplying or not supplying electrical power to the heater in the subsequent time interval in response to the predicted temperature of the structure in order to maintain an actual temperature of the structure between the upper control temperature and lower control temperature;wherein the structure has at least one surface exposed to atmospheric conditions.