Pitot tube including a tube sleeve having a reduced diameter to accommodate a heating element

1. A pitot tube, comprising:

an outer tube extending from a first tube end to second tube end, the second tube end defining a tip portion of the pitot tube, the tip portion including an inlet opening;

a tube sleeve inside of the outer tube at least partially defining a tube passage extending from the first tube end to the second tube end, the tube sleeve including a sleeve outer surface having:

a sleeve body portion having a first outer diameter and a first inner diameter;

a sleeve tip portion disposed at the tip portion of the pitot tube, the sleeve tip portion having a second outer diameter smaller than the first outer diameter and a second inner diameter smaller than the first inner diameter; and

a sleeve radial step connecting the first inner diameter and the second inner diameter; and

a heating element between the outer tube and the tube sleeve at at least the sleeve tip portion;

wherein the tube passage is defined by the first inner diameter, the sleeve radial step and the second inner diameter.

2. The pitot tube of claim 1 , wherein the heating element is disposed at both of the sleeve tip portion and the sleeve body portion.

3. The pitot tube of claim 1 , wherein the heating element is one or more heater coils wrapped around the tube sleeve.

4. The pitot tube of claim 3 , wherein the tube sleeve includes one or more sleeve grooves in the sleeve outer surface to accommodate the heater coils.

5. The pitot tube of claim 1 , wherein the tip portion of the pitot tube converges from an inlet opening diameter at the inlet opening toward the passage throat portion.

6. The pitot tube of claim 5 , wherein the throat opening diameter is less than the inlet opening diameter.

7. The pitot tube of claim 1 , further comprising one or more water dams extending from the tube sleeve into the tube passage.

8. The pitot tube of claim 1 , further comprising one or more drain openings extending from the tube passage through the tube sleeve and through the outer tube.

9. The pitot tube of claim 1 , wherein the tube sleeve is secured to the outer tube via one of brazing or laser metal deposition.

10. A method of forming a pitot tube, comprising:

forming a tube sleeve, the tube sleeve defining a tube passage and including a sleeve outer surface having:

a sleeve body portion having a first outer diameter and a first inner diameter;

a sleeve tip portion disposed at a tip portion of the pitot tube, the sleeve tip portion having a second outer diameter smaller than the first outer diameter and a second inner diameter smaller than the first inner diameter; and

a sleeve radial step connecting the first inner diameter and the second inner diameter; and

the tube passage is defined by the first inner diameter, the sleeve radial step and the second inner

installing a heating element at at least the sleeve tip portion of the tube sleeve; and

securing the tube sleeve in an outer tube such that the heating element is between the tube sleeve and the outer tube.

11. The method of claim 10 , wherein installing the heating element to the tube sleeve comprises:

forming one or more sleeve grooves in the outer surface of the tube sleeve; and

installing the heating element in the one or more grooves.

12. The method of claim 10 , wherein the heating element is a heater coil.

13. The method of claim 10 , further comprising installing the heating element at both the sleeve tip portion and the sleeve body portion.

14. The method of claim 10 , wherein the tube passage includes:

a passage throat portion extending from an inlet opening; and

a passage body portion extending from the passage throat portion opposite the inlet opening, the throat portion having a smaller throat opening diameter than a body opening diameter of the passage body portion.

15. The method of claim 14 , further comprising forming a converging portion in the outer tube from an inlet opening diameter at the inlet opening toward the passage throat portion.

16. The method of claim 15 , wherein the throat opening diameter is less than the inlet opening diameter.

17. The method of claim 10 , further comprising one or more water dams extending from the tube sleeve into the tube passage.

18. The method of claim 10 , further comprising one or more drain openings extending from the tube passage through the tube sleeve and through the outer tube.

19. The method of claim 10 , further comprising securing the tube sleeve to the outer tube via one of brazing or laser metal deposition.