(3)
Check for defects exceeding 0.025 inch over the rest of the head, and exceeding 0.125 inch on the strut section of the probe.
C. Pitot Tip Condition
EFFECTIVITY
ALL 01 Page 601 Apr 25/9734-11-01
SQUARE EDGEROUNDED EDGE
DAMAGED
Inspection Criteria for Static Ports
Figure 601
EFFECTIVITY ALL
701 Page 602
34-11-01
Dec 25/85
197563
Outward Flare of Lip
Figure 603
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701 Page 603
34-11-01
Dec 25/85
REJECTION CRITERION:
1. INDENTATION EXCEEDING 0.030 IN.
Chips or Nicks In Probe Tip
Figure 605
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701 Page 604
34-11-01
Dec 25/85
(1)
The leading edge lip of the pitot opening should be sharp. New probes are sharpened to a 0.006 |0.002 flat. The probe must be removed if the lip has been eroded through wear, or dented by abuse, to the extent that the lip has a flatness greater than
0.015 inch. Figure 602 shows this condition.
(2)
The outer surface of the lip edge must be smooth. It cannot be curled or flared outward. This condition can be detected by sliding your fingernail along the outer surfaces at the tip. The probe should be removed if the lip edge is curled or flared outward. Figure 603 illustrates this condition.
(3)
The lip can have small inward dents which affect the roundness of the pitot opening, as shown in Fig. 604. The probe must be removed if the indentation exceeds 0.030 inch from the normal tip diameter. The dent may be at any location around the opening, but must not affect more than 20% of the lip circumference.
(4)
The leading edge lip can have small nicks or chips as shown in Fig. 605. The probe must be replaced if two of the nicks are between 0.025 and 0.035 inch deep. The probe must also be replaced if any one nick exceeds 0.035 inch deep.
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ALL 01 Page 605 Apr 25/9534-11-01
PITOT-STATIC PROBE - CLEANING/PAINTING
______________________________________
1. Cleaning________
A. Internal
(1) To remove foreign materials lodged in the pitot opening, static ports or drain hole, disconnect the pitot-static probe pressure lines and blow compressed dry air through the line and out the ports. Maximum air pressure to be used is 60 psi.
CAUTION: DO NOT USE FLUIDS THAT CONTAIN SODIUM CHLORIDE OR SULFUR
_______ COMPOUNDS TO CLEAN THE PROBE. SODIUM CHLORIDE AND SULFUR CAN CAUSE PREMATURE FAILURE OF THE PROBE.
(2)
If the forced air method fails to remove the foreign material, remove the pitot-static probe from the airplane (Ref 34-11-01, Pitot-Static Probe - R/I). Soak or flush the unit with clean water, drain it and repeat step (1).
(3)
If the forced air and soaking methods do not clean the drain hole because of its small size, cleaning may be accomplished by manually inserting first a 0.029 drill rod and then a 0.033 drill rod into the drain hole.
CAUTION: CARE MUST BE TAKEN SO THAT THE DRAIN HOLE IS NOT
_______ ENLARGED DURING THE CLEANING PROCESS (DRAIN HOLE DIAMETER IS 0.033 |0.001 INCH).
B. External
CAUTION:_______DO NOT PAINT THE EXTERNAL SURFACE OF THE PROBE. YOU MAY CAUSE THE PROBE TO FUNCTION INCORRECTLY.
(1) To remove foreign material from external surfaces, wash them with clean water and dry them with a soft cloth.
CAUTION:_______DO NOT PROBE INTO THE STATIC PORTS WITH ANY OBJECT. DO NOT EXPOSE PITOT-STATIC TUBES TO SOLVENTS, LUBRICATING OIL AND/OR GREASE. DO NOT SCOUR OR BUFF THE MACHINED CONTOUR SURFACE.
EFFECTIVITY
ALL 01 Page 701 Dec 25/9234-11-01
ALTERNATE STATIC PORT - REMOVAL/INSTALLATION
____________________________________________
1. Referenced Procedures
_____________________
A. 20-30-01, Maintenance Practices
B. 20-30-02, Maintenance Practices
C. 20-30-05, Maintenance Practices
D. 25-52-01, Removal/Installation
E. 34-11-00, Maintenance Practices
F. 34-11-00, Adjustment/Test
2. Equipment and Materials
_______________________
A. Alodize Compound - Class B, Method 2 (Ref 20-30-02)
B. Sealant - BMS 5-26, Class B (Proseal 890 only) (Ref 20-30-05)
C. Cleaner - BMS 11-7 (Ref 20-30-01)
3. Remove Alternate Static Port (Fig. 401)
____________________________
A. Inside forward cargo area, locate left or right alternate static port between first two bulkheads aft of cargo door at about floor level. Remove hardliner wall (Ref 25-52-01). Station a man outside airplane by static port to be removed.
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