Volume 2-757
34-00-01 
Page 1 OCT 01/00 
CORROSION PREVENTION MANUAL 
NAVIGATION
THIS PAGE INTENTIONALLY LEFT BLANK
Volume 2-757
34-00-01 
Page 2 OCT 01/00 
CORROSION PREVENTIONMANUAL 
RADIO ALTIMETER ANTENNA
1. General
A. There are six radio altimeter antennas on the bottom of the fuselage. Intru-sion of water at the antenna connector base will cause delamination and cor-rosion and eventually cause the antenna to be inoperable.
2. Corrosion Prevention
A. Periodically inspect the antennas for evidence of corrosion. Refer to Main-tenance Manual Subject 34-33-02 for removal procedure.
B. If corrosion is evident, replace with new antenna.
C. Clean faying surfaces of antenna and mounting surfaces and apply Alodine 
1200. Airplanes line number 94 and on, plus those incorporating SB 34-0025, 
will have the antenna bases packed with grease.
D. Apply BMS 3-23 to the connector base, including the nuts. Pack the connector 
base with BMS 3-24 grease from the 0-ring on the backplate to above the nuts 
on the connector base.
E. Install and test the antenna per MM 34-33-02.
Volume 2-757
34-30-01 
Page 1 
OCT 01/00
CORROSION PREVENTION MANUAL 
RADIO ALTIMETER ANTENNA
RADIO ALTIMETER ANTENNA (CENTER) DETAIL I 
RADIO ALTIMETER ANTENNA 
(LEFT SHOWN, RIGHT OPPOSITE) 
DETAIL II
AERODYNAMIC SEALANT (TYPICAL) 
DETAIL III
DETAIL IV
Radio Altimeter Antenna 
Figure 1
Volume 2-757
34-30-01
Page 2 
OCT 01/00
CORROSION PREVENTION MANUAL 
TRAFFIC ALERT AND COLLISIONAVOIDANCE SYSTEM (TCAS)
1. General
A. This system includes an antenna installed in the bilge area on the bottom 
skin of the airplane, at station 446.50. Water can collect in the low area 
around the hole in the skin, ring doubter, and coverplate. This can result 
in corrosion of the antenna connectors.
2. Corrosion Prevention
A. Make regular checks of the antenna connectors for corrosion. To prevent cor-rosion, install a moisture guard at the antenna location per SB 34-0073.
Volume 2-757
34-40-01 
Page 1 
OCT 01/00
CORROSION PREVENTION MANUAL 
TRAFFIC ALERT AND COLLISIONAVOIDANCE SYSTEM (TCAS)
E3 ELECTRICAL RACK REMOVED
Traffic Alert and Collision Avoidance System Lower Antenna 
Figure 1 (Sheet 1)
Volume 2-757
34-40-01 
Page 2 OCT 01/00 
CORROSION PREVENTION MANUAL 
TRAFFIC ALERT AND COLLISION AVOIDANCE SYSTEM (TCAS)
SECTION A-A
Traffic Alert and Collision Avoidance System Lower Antenna 
Figure 1 (Sheet 2)
Volume 2-757
中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址:757 防腐手册 CORROSION PREVENTION MANUAL(12)