There are four levels of maintenance Line replacement unit (LRU)-level maintenance. Shop replacement unit (SRU)-level maintenance. Depot-level maintenance. Factory-level or manufacturer-level maintenance.

1. AVIATION MAINTENANCE LEVELS
MUHAMMED IBRAR
AVIONICS SYSTEM DESIGN
DEPARTMENT OF AVIONICS ENGINEERING

2. LEVELS OF MAINTENANCE
There are four levels of maintenance
1. Line replacement unit (LRU)-level maintenance.
2. Shop replacement unit (SRU)-level maintenance.
3. Depot-level maintenance.
4. Factory-level or manufacturer-level maintenance.

3. LRU LEVEL MAINTENANCE.
AN/ARC-164 UHF Airborne Radio
• It is an LRU of FT-5 fighter aircraft
• It is used for communication in the air to air and air to ground

4. SRU LEVEL MAINTENANCE.
There 5 parts of AN/ARC-164 Radio these are SHOP REPLACEMENT UNIT
(SRU) of Line Replaceable Units (LRU).
• DATA CONVERTER
• SYNTHESIZER
• GUARD RECEIVER
• MAIN RECEIVER
• TRANSMITTER

5. DEPOT-LEVEL MAINTENANCE
Depot-level maintenance is third-level maintenance.
Front side and backplane of SRU

6. FACTORY-LEVEL OR MANUFACTURER-LEVEL
• Components that are used in the SRU are replaced on FACTORY-LEVEL
OR MANUFACTURER-LEVEL Maintenance. Like Resistor, Capacitor, ICS,
and other components.
• Level 4 maintenance operations are complex and of great importance,
requiring special technical expertise.
• There are two types of components to solder on the front plane of the
SRU
1. SURFACE MOUNT DEVICE (SMD)
2. THROUGH-HOLE DEVICE

7. SURFACE MOUNT DEVICE (SMD)
• An electronic component that mounts on the surface of a printed
circuit board.
• Very high sophisticated machine required for soldering of SMD.

8. THROUGH-HOLE DEVICE
• Through-hole components are best used for high-reliability products
that require stronger connections between layers.