Tailored rotor-blade ice-protection system

1. An ice protection system for a rotor blade, the blade having a leading edge along at least a portion of a spanwise length extending between a root portion and a tip portion, the system comprising:

an electric spanwise anti-ice heater configured for continuous heating during operation and for placement on the leading edge of the blade, the anti-ice heater extending continuously from the tip portion to the root portion and having opposing spanwise edges defining a chordwise width of the anti-ice heater, portions of the spanwise edges extending away from a centerline of the anti-ice heater in alternating directions:

a first electric spanwise de-ice heater having an edge adjacent one of the spanwise edges of the anti-ice heater and having varying chordwise dimensions, the first de-ice heater being configured for intermittent heating during operation and for placement on an upper surface of the blade or a lower surface of the blade; and

electrical connectors for each heater, the connectors being configured for connection near the root portion of the blade to a source of electrical power.

2. The system of claim 1 , further comprising:

a second electric spanwise de-ice heater having an edge adjacent the other of the spanwise edges of the anti-ice heater and having varying chordwise dimensions, the second de-ice heater being configured for intermittent heating during operation and for placement on an upper surface of the blade or a lower surface of the blade.

3. The system of claim 1 , wherein an interlocking pattern is formed between the edge of the first de-ice heater and the adjacent edge of the anti-ice heater.

4. The system of claim 3 , wherein the interlocking pattern is sinuous.

5. The system of claim 3 , wherein the interlocking pattern is castellated.

6. The system of claim 1 , wherein a watt density of at least one of the heaters varies along its spanwise length.

7. An ice protection system for a rotor blade, the blade having a leading edge along at least a portion of a spanwise length extending between a root portion and a tip portion, the system comprising:

an electric spanwise anti-ice heater configured for continuous heating during operation and for placement on the leading edge of the blade, the anti-ice heater extending continuously from the tip portion to the root portion and having opposing spanwise edges defining a chordwise width of the anti-ice heater, portions of the spanwise edges extending away from a centerline of the anti-ice heater in alternating directions:

a first electric spanwise de-ice heater having an edge adjacent one of the spanwise edges of the anti-ice heater and having varying chordwise dimensions, the first de-ice heater being configured for intermittent heating during operation and for placement on an upper surface of the blade or a lower surface of the blade;

a second electric spanwise de-ice heater having an edge adjacent the other of the spanwise edges of the anti-ice heater and having varying chordwise dimensions, the second de-ice heater being configured for intermittent heating during operation and for placement on an upper surface of the blade or a lower surface of the blade; and

electrical connectors for each heater, the connectors being configured for connection near the root portion of the blade to a source of electrical power.

8. The system of claim 7 , wherein an interlocking pattern is formed between the edge of the first de-ice heater and the adjacent edge of the anti-ice heater.

9. The system of claim 8 , wherein the interlocking pattern is sinuous.

10. The system of claim 8 , wherein the interlocking pattern is castellated.

11. The system of claim 7 , wherein a watt density of at least one of the heaters varies along its spanwise length.

12. An ice protection system for a rotor blade, the blade having a leading edge along at least a portion of a spanwise length extending between a root portion and a tip portion, the system comprising:

an electric spanwise anti-ice heater configured for continuous heating during operation and for placement on the leading edge of the blade, the anti-ice heater extending continuously from the tip portion to the root portion and having opposing spanwise edges defining a chordwise width of the anti-ice heater, portions of the spanwise edges extending away from a centerline of the anti-ice heater in alternating directions:

a first electric spanwise de-ice heater having an edge adjacent one of the spanwise edges of the anti-ice heater and having varying chordwise dimensions, the first de-ice heater being configured for intermittent heating during operation and for placement on an upper surface of the blade or a lower surface of the blade; and

electrical connectors for each heater, the connectors being configured for connection near the root portion of the blade to a source of electrical power;

wherein a watt density of at least one of the heaters varies along its spanwise length.

13. The system of claim 12 , further comprising:

a second electric spanwise de-ice heater having an edge adjacent the other of the spanwise edges of the anti-ice heater and having varying chordwise dimensions, the second de-ice heater being configured for intermittent heating during operation and for placement on an upper surface of the blade or a lower surface of the blade.

14. The system of claim 12 , wherein an interlocking pattern is formed between the edge of the first de-ice heater and the adjacent edge of the anti-ice heater.

15. The system of claim 14 , wherein the interlocking pattern is sinuous.

16. The system of claim 14 , wherein the interlocking pattern is castellated.