Service Bulletin SB-550-21| Name | Revision | Lang | Subject | Date |
|---|
| 550-21-5 | | en | AIR DISTRIBUTION SYSTEM ORIFICE INSPECTION/MODIFICATION | 08/06/1979 |
| 550-21-13 | | en | AIR CONDITIONING - FLOOD COOLING DUCT MODIFICATION | 02/03/1983 |
| SB550-21-1 | 1 | en | CABIN LOWER AIR DISTRIBUTION SYSTEM MODIFICATION | 06/18/1979 |
| SB550-21-4 | 2 | en | SUPPLEMENTAL COCKPIT AIR DISTRIBUTION SYSTEM | 03/25/1981 |
| SB550-21-10 | 3 | en | PRESSURIZATION SYSTEM - FLOW VALVE REPLACEMENT | 05/28/1982 |
| SB550-21-12 | 2 | en | Mandatory AIR CONDITIONING - COMPRESSOR RECYCLING TIMER INSTALLATION | 02/25/1983 |
| SB550-21-15 | 1 | en | Mandatory AIR CONDITIONING - CABIN DOOR SEAL PLUMBING HEAT DUCT INSTALLATION | 08/19/1983 |
| SB550-21-16 | | en | AIR CONDITIONING - FREON AIR CONDITIONING LOW PRESSURE SWITCH DISABLEMENT | 04/06/1984 |
| SB550-21-20 | 2 | en | AIR CONDITIONING - CABIN VENTILATION MOTOR REPLACEMENT | 12/01/1993 |
| SB550-21-21 | | en | Mandatory AIR CONDITIONING - RAM AIR ELBOW INSTALLATION | 06/08/1984 |
| SB 550-21-22 | 1 | en | Mandatory AIR CONDITIONING - FRESH AIR DUCT INSTALLATION | 12/23/1987 |
| SB550-21-25 | | en | AIR CONDITIONING - FLOW CONTROL VALVES TEMPORARY SPARES REPLACEMENT | 11/03/1989 |
| SB550-21-28 | | en | AIR CONDITIONING - DUCT OVERHEAT SENSOR RELOCATION | 03/15/1991 |
| SB550-21-30 | 2 | en | AIR CONDITIONING - ACM INLET DUCT INSTALLATION AND CABIN FRESH AIR DUCT MODIFICATION | 03/01/1993 |
| SB550-21-32 | 1 | en | AIR CONDITIONING - AVIONICS COOLING (ACM2) AIR DISTRIBUTION SYSTEM MODIFICATION | 03/02/1992 |
| SB550-21-33 | 1 | en | Emergency AIR CONDITIONING - EMERGENCY PRESSURIZATION ORIFICE PLATE INSPECTION/INSTALLATION | 05/01/1991 |
| SB550-21-35 | 1 | en | AIR CONDITIONING - TAILCONE PRESSURE VALVE ACTUATOR WIRING MODIFICATION | 01/23/1998 |
| SB550-21-38 | 1 | en | AIR CONDITIONING - COCKPIT COOLING DUCT INSTALLATION | 06/16/1993 |
| SB550-21-39 | | en | Mandatory AIR CONDITIONING - OUTFLOW VALVE REPLACEMENT | 09/01/1992 |
| SB550-21-40 | | en | AIR CONDITIONING - P10 PANEL ACCESS AIR DUCT MODIFICATION | 10/28/1994 |
| SB550-21-44 | | en | AIR CONDITIONING - RAM AIR DUCT IMPROVEMENT | 07/19/1999 |
| SB550-21-47 | | en | AIR CONDITIONING - COCKPIT SIDE WINDOW DEFOG SYSTEM MODIFICATION | 05/24/2000 |
| SB550-21-48 | 1 | en | AIR CONDITIONING - CABIN FAN AND DEFOG BLOWER WIRING IMPROVEMENT | 06/16/2003 |
| SB550-21-49 | | en | Alert AIR CONDITIONING - CABIN FAN AND DEFOG BLOWER WIRING IMPROVEMENT | 06/16/2003 |
| SB550-21-50 | | en | AIR CONDITIONING - RAM AIR DUCT IMPROVEMENT | 12/13/2004 |
| SB550-21-51 | | en | AIR CONDITIONING - DEFOG BLOWER BONDING JUMPER | 03/16/2007 |
| SB550-21-54 | | en | AIR CONDITIONING - WATER SEPARATOR TEMPERATURE SENSOR WIRING MODIFICATION | 10/05/2007 |
