EFFECTIVITY

ALL 7XA Page 402
34-33-03

 Apr 25/80
WING TO BODY
FAIRING PANEL

FAYING SURFACE. ELECTRICAL BONDING PATH IS FROM ANTENNA THRU MOUNTING RING, WASHER TO ALUMINUM COATING ON PANEL

LRRA Antenna - Removal/Installation
Figure 401 (Sheet 2)

EFFECTIVITY ALL

701 Page 403
34-33-03

Jul 15/74
 NOTE: Coaxial connector at R/T unit end of cable must be isolated from
____
 airplane structure during electrical bonding measurement.

 H.  Connect the bonding meter between the antenna base and the airplane skin.
 I.  Make sure the resistance is not more than .025 ohms (SWPM 20-20-00).
 J.  Install the last screw holding antenna to mounting ring and tighten.
 K.  Apply aerodynamic sealant, BMS 5-95 to the outer edge of the antenna base and to the head of each screw (AMM 51-31-01/201).
 L.  Deleted.
 M.  Connect antenna coaxial cable to R/T unit.
 N.  Close circuit breakers opened in paragraph 3 above.
 O.  Test antenna for satisfactory operation as follows:
 (1)  
Provide electrical power (AMM 24-22-00/201).

 (2)  
On AF, AT, GN, MD and VM airplanes,
 turn on LRRA system at appropriate height indicator.

 (3)  
For LRRA systems 1 or 2, check that height indicator warning flag is out of view.

 (4)  
Perform LRRA system operational tests (A/T section, Chapter
 34-33-00).

 (5)  
On AF, AT, GN, MD and VM airplanes,
 turn off LRRA system, or as required.

 (6)  
Remove electrical power if no longer required (AMM 24-22-00/201).

 EFFECTIVITY

 
 ALL  11 Page 404  Apr 25/9834-33-03
 LRRA ANTENNAS - APPROVED REPAIRS
________________________________

 1.  General_______
 A.  Inadequate RF bonding between LRRA antenna and structure can cause nuisance flags and/or substantial disagreement in readings between systems at high altitudes.
 B.  The following approved repair improves the RF bond by adding conductive cadmium plate nuts.
 2.  Equipment and Materials_______________________
 A.  Nuts - Cadmium plated, MS25082-2
 B.  Washers - dimpled, BACW1OUC8
 C.  Screws - BACB3OLH2-3
 3.  Repair LRRA Antenna Bonding___________________________
 A.  Remove LRRA antenna (Ref 34-33-03, Removal/Installation).
 B.  Remove BACN10JC08CM self-locking nuts from 16 screws that secure antenna mounting ring to fairing panel.
 C.  Thoroughly clean paint and corrosion from around screw holes on mounting ring and flame-sprayed fairing panel.
 D.  Replace any dimpled washers (under screw heads) or screws that may have been deformed or damaged by overtorquing.
 E.  Reassemble mounting ring to fairing panel using MS25082-2 cadmium plated nuts.
 CAUTION:_______DO NOT DAMAGE DIMPLED WASHERS BY OVERTORQUING. EACH WASHER MUST MAKE CONTACT WITH FLAME-SPRAY COATING ON FAIRING PANEL OVER AT LEAST 50% OF ITS CIRCUMFERENCE.
 NOTE: Screws must be long enough to allow reinstallation of self-
____ locking nuts. Delete, as required, buildup washers that were originally used under self-locking nuts or use longer screws.

 F.  Replace self-locking nuts removed in step 3.B. and tighten against cadmium plated nuts.
 G.  Install LRRA antenna (Ref 34-33-03, Removal/Installation).
 EFFECTIVITY

 

 ALL  01 Page 801  Oct 10/7334-33-03
 HEIGHT INDICATOR - REMOVAL/INSTALLATION
_______________________________________

 1.  General
_______
 A.  A height indicator is mounted on each pilots' instrument panel.
 2.  Referenced Procedures
_____________________
 A.  24-22-00, Maintenance Practices (Apply Power)
 3.  Remove Height Indicator
_______________________
 A.  Open ALTM LOW Rl or R2 circuit breaker on overhead circuit breaker panel P7.
 B.  Remove indicator from instrument panel and disconnect electrical connector.
 4.  Install Height Indicator
________________________
 A.  Connect electrical connector to indicator and secure indicator to mounting in instrument panel.
 B.  Close circuit breaker opened in paragraph 3.A.
 C.  Test height indicator for satisfactory operation as follows:
　
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