# JASC 4910: APU Cowling/Containment

- Type: JASC system/component code (FAA)
- ATA chapter: 49 Airborne Auxiliary Power
- Title in the code table: APU COWLING/CONTAINMENT
- Service difficulty reports: 953
- FAA code table: https://www.faa.gov/sites/faa.gov/files/JASC_Code.pdf#page=44
- Page: https://openairdocs.org/jasc/4910

## What it covers

The system of cowling and other components used to cover the auxiliary power unit, and contain any broken parts in the event of an external failure.

## Service difficulty reports (953, newest 50)

- [SDR CALA2026102120505](https://openairdocs.org/sdr/CALA2026102120505), Oct 19, 2026: Boeing 777300ER. SEAL. DAMAGED. APU MOUNT CHECK, INLET DUCT PLENUM SEAL IS DISTORTED ON LT SIDE. REMOVED APU AIR INLET PLENUM SEAL IAW AMM 49-15-04 & RE (N2331U)
- [SDR SWIA2026101677758](https://openairdocs.org/sdr/SWIA2026101677758), Oct 16, 2026: Cndair CL6002B19. STRUCTURE. DAMAGED. FOUND TOOLING DAMAGE AT RT BS 672.20, BEHIND APU SHIELD. BLENDED DAMAGE, PERFORMED UT REMAINING THICKNESS MEASUREMENT IA (N913EV)
- [SDR JR2R20261016817](https://openairdocs.org/sdr/JR2R20261016817), Oct 16, 2026: Emb ERJ170200LL. ACCESS DOOR. BENT. APU PANEL 351GL HAS CORNER OF PANEL BENT AT FWD L/H EDGE. REPAIRED PER ETD. (N88359)
- [SDR HNAA2026101901011](https://openairdocs.org/sdr/HNAA2026101901011), Sep 27, 2026: Emb EMB145LR. FIREWALL. CRACKED. APU FIREWALL WAS CRACKED ABOVE UPPER LEFT APU MOUNT ATTACH BRACKET. PERFORMED DOUBLER AND FILLER REPAIR ON APU FIREWALL  (N656AE)
- [SDR IPXA2026101613332](https://openairdocs.org/sdr/IPXA2026101613332), Sep 18, 2026: Boeing 75724APF. PANEL. DELAMINATED. MAJOR REPAIR, LOWER AFT APU PANEL BETWEEN BS 1963 TO 1992 IS DELAMINATED VERIFIED STEP 14 IS ACCOMPLISHED AND HEAT CON.  (N402UP)
- [SDR CALA2026092819931](https://openairdocs.org/sdr/CALA2026092819931), Sep 18, 2026: Boeing 737824. ANGLE. CORRODED. APU BAY L/H CUTOUT FWD TWO BRACKETS WITH CORROSION. REMOVED AND REPLACED APU BAY LT CUTOUT ANGLE IAW SRM 51-40-02-0G -0  (N73299)
- [SDR JR2R20260914503](https://openairdocs.org/sdr/JR2R20260914503), Sep 14, 2026: Emb ERJ170200LR. BULKHEAD. CRACKED. APU BLKHEAD PANEL 351BZ IS CRACKED. REPAIR. (N88327)
- [SDR IPXA2026101698760](https://openairdocs.org/sdr/IPXA2026101698760), Sep 11, 2026: Boeing 75724APF. SKIN. DELAMINATED. MAJOR REPAIR, APU COMPARTMENT SKIN PANEL HAS EVIDENCE OF DELAMINATION APPROX BTW BS 1885 AND BS 1896, STGR 17R AREA, (N402UP)
- [SDR HNAA2026101601002](https://openairdocs.org/sdr/HNAA2026101601002), Sep 10, 2026: Emb EMB145LR. FIREWALL. CRACKED. APU FIREWALL CRACKED AT RH EDGE BTW STR11-12R. REPAIRED IAW ETD 2026-145-015767 (N650AE)
- [SDR HNAA2026101601000](https://openairdocs.org/sdr/HNAA2026101601000), Sep 10, 2026: Emb EMB145LR. FIREWALL. CRACKED. 53-2245 APU FIREWALL CRACKED AT RH EXTINGUISHER NOZZLE. REPAIRED IAW ETD 2026-145-015767 REV C AND EO 1-53-26-0481 (N650AE)
- [SDR IPXA2026100276207](https://openairdocs.org/sdr/IPXA2026100276207), Sep 10, 2026: Boeing 75724APF. BULKHEAD. DENTED. MAJOR REPAIR, APU COMPARTMENT STA 1885 BULKHEAD REPAIR DOUBLE 10" INCHES RIGHT OF LIGHT SWITCH DENTED IN AND EDGES ROLLE (N402UP)
- [SDR IPXA2026101780235](https://openairdocs.org/sdr/IPXA2026101780235), Sep 4, 2026: Boeing 75724APF. BRACKET. CORRODED. ALL APU COMPARTMENT L/H SIDE CEILING ELECTRICAL WIRE HARNESS SUPPORT BRACKETS HAVE CORROSION AND MISSING PROTECTIVE FINI (N463UP)
- [SDR IPXA2026100280598](https://openairdocs.org/sdr/IPXA2026100280598), Sep 4, 2026: Boeing 75724APF. SKIN. DELAMINATED. MAJOR REPAIR, APU COMPARTMENT R/H SIDE COMPOSITE SKIN PANEL SECTION BETWEEN STA 1918 AND 1941 DELAMINATED. RL038 QCI(RII (N463UP)
- [SDR IPXA2026100280618](https://openairdocs.org/sdr/IPXA2026100280618), Sep 4, 2026: Boeing 75724APF. SKIN. DELAMINATED. MAJOR REPAIR, APU COMPARTMENT R/H SIDE COMPOSITE SKIN PANEL SECTION BETWEEN STA 1941 AND 1963 DELAMINATED. RL039 QCI(RII (N463UP)
- [SDR IPXA2026090486275](https://openairdocs.org/sdr/IPXA2026090486275), Sep 4, 2026: Boeing 75724APF. SKIN. DEBONDED. APU COMPARTMENT, RT SIDE HONEYCOMB SKIN PANEL DISBONDED AREA BETWEEN FRAME STA 1918 AND 1941 AND 24" ABOVE LONGERON 17R. (N461UP)
- [SDR IPXA2026101678146](https://openairdocs.org/sdr/IPXA2026101678146), Sep 3, 2026: Boeing 75724APF. SUPPORT BRACKET. DAMAGED. STR, ATA 49: APU AIR INTAKE DUCT EXTERNAL DRAIN TUBE SUPPORT BRACKET HAS CORROSION. RL020. INSTALLED NEW BRACKET SUPPORT (N463UP)
- [SDR IPXA2026090916126](https://openairdocs.org/sdr/IPXA2026090916126), Aug 25, 2026: Boeing 75724APF. STRAP. CORRODED. MAJOR REPAIR, APU INLET DOOR AFT STRAP HAD CORROSION. REMOVED OUTER STRAP IAW SRM 51-40-02-0G-0. INSTALLED NEW REPAIR PA (N441UP)
- [SDR IPXA2026082620255](https://openairdocs.org/sdr/IPXA2026082620255), Aug 4, 2026: Boeing 75724APF. BULKHEAD. CORRODED. APU COMPARTMENT FWD BULKHEAD FWD SIDE BS 1885.2, LBL 12 & RBL 9. EXTENSIVE CORROSION. (N461UP)
- [SDR HNAA2026082500780](https://openairdocs.org/sdr/HNAA2026082500780), Jul 28, 2026: Emb EMB145LR. FIREWALL. CRACKED. APU FIREWALL CRACKED. REPAIRED IAW SRM 53-32-12 (N925AE)
- [SDR 2026FA0000602](https://openairdocs.org/sdr/2026FA0000602), Jul 27, 2026: Airbus A320214. ISOLATOR. WRONG PART. DURING APU ISOLATOR MOUNT REPLACEMENT IT WAS DISCOVERED THAT THE ORIENTATION OF THE VIBRATION MOUNT HAD BEEN INSTALLED 9 (N320FR)
- [SDR IPXA2026091153139](https://openairdocs.org/sdr/IPXA2026091153139), Jul 25, 2026: Boeing 75724APF. SKIN. DEBONDED. APU COMPARTMENT R/H SIDE HONEYCOMB SKIN PANEL DISBONDED AREA BETWEEN FRAME STA 1918 AND 1941 AND 24" ABOVE LONGERON 17R. (N461UP)
- [SDR IPXA2026082254285](https://openairdocs.org/sdr/IPXA2026082254285), Jul 25, 2026: Boeing 75724APF. SUPPORT BRACKET. CORRODED. APU COMPARTMENT, FWD BULKHEAD BS 1885, ALL WIRE HARNESSES AND POWER CABLE CLAMP SUPPORT BRACKETS ATTACHED TO BULKHEAD HA (N461UP)
- [SDR IPXA2026081286146](https://openairdocs.org/sdr/IPXA2026081286146), Jul 16, 2026: Boeing 75724APF. RETAINER. WORN. APU COMPARTMENT FWD BULKHEAD SAFETY CATCH ANGLE FOR RT APU DOOR 316AR WORN THIN. RL017. INSTALLED 1 NEW RETAINER AT STA  (N455UP)
- [SDR IPXA2026081501707](https://openairdocs.org/sdr/IPXA2026081501707), Jul 16, 2026: Boeing 75724APF. SKIN. CORRODED. APU COMPARTMENT TAIL CONE LOWER BILGE ALUMINUM HONEYCOMB SKIN PANELS BETWEEN BS 1963 & 1992 HAD AREAS OF CORROSION TO IN (N455UP)
- [SDR IPXA2026071089100](https://openairdocs.org/sdr/IPXA2026071089100), Jun 27, 2026: Boeing 75724APF. SUPPORT BRACKET. CRACKED. APU INLET DUCT WITH BRACKET BROKEN. REMOVED BRACKET IAW B757-200 SRM 51-40-02. INSTALLED NEW PARTS (BRACKET SUPPORT) AT  (N453UP)
- [SDR CALA2026062217249](https://openairdocs.org/sdr/CALA2026062217249), Jun 20, 2026: Boeing 737824. ATTACH FITTING. GOUGED. GOUGE - AFT LT APU MOUNT ATTACH FITTING WITH GOUGE AT LOWER EDGE. AFT LT APU MOUNT ATTACH FITTING. ACCOMPLISHED REPAIR A (N79541)
- [SDR HNAA2026072400625](https://openairdocs.org/sdr/HNAA2026072400625), Jun 18, 2026: Emb EMB145LR. ACCESS PANEL. CRACKED. APU COWLING ACCESS PANEL CRACKED ON THE INTERIOR SIDE NEAR THE HINGE. REMOVED AND REPLACED APU COWLING ACCESS PANEL PER  (N931AE)
- [SDR IPXA2026061827919](https://openairdocs.org/sdr/IPXA2026061827919), Jun 18, 2026: Boeing 75724APF. ANGLE. CORRODED. HORZIZONAL STAB COMPT. APU INLET SURROUND STRUCTURE ANGLE IS CORRODED BETWN STA. 1787.45 TO 1825 STGR S-6R (059-07) ATA: (N429UP)
- [SDR FDEA202605290652](https://openairdocs.org/sdr/FDEA202605290652), May 29, 2026: Boeing 75728A. SKIN. DELAMINATED. APU COMPARTMENT INTERNAL SKIN AT BS 1900 DELAMINATED APPLIED PERMANENT AT APU COMPARTMENT INTERNAL SKIN IAW B757 SRM 51- (N912FD)
- [SDR IPXA2026061201031](https://openairdocs.org/sdr/IPXA2026061201031), May 28, 2026: Boeing 75724APF. STRAP. CORRODED. APU INLET DOOR AFT STRAP HAS CORROSION STA1825.00,S-3R TO S6R. INSTALLED PARTS OF REPAIR (STRAP 1, STRAP 2, FILLER 3, FI (N413UP)
- [SDR IPXA2026061244983](https://openairdocs.org/sdr/IPXA2026061244983), May 24, 2026: Boeing 75724APF. STRAP. CORRODED. APU INLET DOOR FWD STRAP HAS CORROSION INSTALLED NEW FWD STRAP I.A.W SRM 51-40-02-0G-0. (N413UP)
- [SDR IPXA2026061344863](https://openairdocs.org/sdr/IPXA2026061344863), May 24, 2026: Boeing 75724APF. ANGLE. CORRODED. APU INLET DOOR BETWEEN BS 1787.45 TO BS 1825 S-6R, LOWER ANGLE HAS CORROSION. INSTALLED NEW LOWER ANGLE IAW SRM 51-40-02 (N413UP)
- [SDR JJBA20260520021](https://openairdocs.org/sdr/JJBA20260520021), May 11, 2026: Emb EMB145XR. SHEAR PANEL. GOUGED. APU INTERIOR GOUGE ON SHEAR PANEL. BLEND OUT WAS PERFORMED. (N17159)
- [SDR JJBA20260520020](https://openairdocs.org/sdr/JJBA20260520020), May 11, 2026: Emb EMB145XR. FRAME. BENT. APU INTERIOR, FRAME SHAPE U FWD-TO-REAR MULTIPLES BENT. RECOUNTOUR WAS PERFORMED. (N17159)
- [SDR IPXA2026051005536](https://openairdocs.org/sdr/IPXA2026051005536), May 9, 2026: Boeing 75724APF. STRAP. CORRODED. BS 1825 APU INTAKE DOOR SURROUND AFT STRAP HAS CORROSION ON AN EXISTING REPAIR ACCOMPLISH THE REPAIR IAW SRM 53-80-15-2R (N423UP)
- [SDR JJBA20260520022](https://openairdocs.org/sdr/JJBA20260520022), May 9, 2026: Emb EMB145XR. SKIN. CANNING. LH APU SKIN OIL CANNING AND DENT. PERMANENT REINFORCEMENT REPAIR WAS PERFORMED. (N17159)
- [SDR IPXA2026050681325](https://openairdocs.org/sdr/IPXA2026050681325), Apr 25, 2026: Boeing 75724APF. ANGLE. CORRODED. APU INLET DOOR LOWER CORNER ANGLE AT STA 1787.45 S-R6 HAS EVIDENCE OF CORROSION. INSTALLED NEW LOWER CORNER ANGLE I.A.W. (N440UP)
- [SDR JJBA20260423025](https://openairdocs.org/sdr/JJBA20260423025), Apr 17, 2026: Emb EMB145XR. SKIN. CANNING. APU SKIN OIL CANNING UPPER BETWEEN PROFILES, SIDE LH. REPAIRED APU COWLING SKIN. (N14177)
- [SDR JJBA20260423024](https://openairdocs.org/sdr/JJBA20260423024), Apr 16, 2026: Emb EMB145XR. SKIN. CHAFED. APU COWLING SHEAR PANEL HAS SEVERAL CHAFING ON SKIN. PERMANENT REPAIR WAS PERFORMED. (N14177)
- [SDR JJBA20260423023](https://openairdocs.org/sdr/JJBA20260423023), Apr 16, 2026: Emb EMB145XR. SKIN. DAMAGED. APU COWLING INTERNAL SKIN GOUGE-DENT. PERMANENT REPAIR WAS PERFORMED. (N14177)
- [SDR YENA2026041700406](https://openairdocs.org/sdr/YENA2026041700406), Apr 15, 2026: Airbus A320232. ACCESS PANEL. CORRODED. DURING HEAVY MAINTENANCE: CORROSION ACCESS PANEL 316AR FWD CORNER LOWER POSITION IN APU COMPARTMENT; PERFORMED PERMANENT (N624JB)
- [SDR CALA2026041615407](https://openairdocs.org/sdr/CALA2026041615407), Apr 15, 2026: Boeing 737724. ANGLE. CORRODED. APU COMPARTMENT LEFT SIDE LOWER FRAME HAS LIGHT CORROSION IN SEVERAL SPOTS. ACCOMPLISHED ESFR FORM AS PER GMM 04-20-05.  (N24736)
- [SDR REXA2026051500592](https://openairdocs.org/sdr/REXA2026051500592), Apr 13, 2026: Cndair CL6002D24. DUCT. CRACKED. CRACK ON APU EXHAUST DUCT (INTERNAL AREA). CRACK ON APU EXHAUST DUCT (INTERNAL AREA) WAS WELDED PER HONEYWELL CMM REPAIR (N137EV)
- [SDR IPXA2026041853943](https://openairdocs.org/sdr/IPXA2026041853943), Apr 11, 2026: Boeing 75724APF. STRAP. CORRODED. CORRODED FWD STRAP AT APU AIR INTAKE INLET CUTOUT. INSTALLED NEW STRAP FROM FWD STRAP AT APU AIR INTAKE INLET CUTOUT IAW (N421UP)
- [SDR IPXA2026041025522](https://openairdocs.org/sdr/IPXA2026041025522), Apr 9, 2026: Boeing 75724APF. STRAP. CORRODED. EMPENAGE THROUGHT ACCESS PANEL 311AL STRUCTURE THAT ATTACH APU INLET DOOR HAVE CORROSION 07-005 INSTALLED APU AIR INTAKE (N421UP)
- [SDR IPXA2026042176560](https://openairdocs.org/sdr/IPXA2026042176560), Apr 7, 2026: Boeing 75724APF. STRAP. CORRODED. WHILE EVALUATING CORROSION AT APU INLET SURROUND STRUCTURE FOUND CORROSION AT APU INLET AFT STRAP AT STA 1825 BETWEEN ST (N454UP)
- [SDR IPXA2026041134931](https://openairdocs.org/sdr/IPXA2026041134931), Apr 4, 2026: Boeing 75724APF. STIFFENER. INOPERATIVE. APU COMPARTMENT FWD BULKHEAD STA 1885 HORZ STRIFFENER JUST BELOW LIGHT SWITCH ASSY HAS AREAS OF LITE CORROSION, BENT AND (N454UP)
- [SDR IPXA2026041735211](https://openairdocs.org/sdr/IPXA2026041735211), Apr 4, 2026: Boeing 75724APF. SUPPORT BRACKET. CORRODED. APU COMPARTMENT FWD BULKHEAD STA 1885 CEILING WIRE HARNESS CLAMP SUPPORT BRACKETS 6 EACH UPPER AND LOWER SIDES HAVE LIGH (N454UP)
- [SDR IPXA2026041136020](https://openairdocs.org/sdr/IPXA2026041136020), Mar 29, 2026: Boeing 75724APF. SKIN. PUNCTURED. APU COMPARTMENT LT INERNAL SKIN AT BS 1918 HAVE HONEYCOMB WITH HOLE. REMOVED DAMAGE AND PREPARED AREA IAW SRM 51-70-10-2 (N430UP)
- [SDR CALA2026030914414](https://openairdocs.org/sdr/CALA2026030914414), Mar 5, 2026: Boeing 757224. DOOR. CORRODED. APU INLET DOOR CUTOUT AND A BOLT, UPPER AFT CORNER HAVE EVIDENCE OF CORROSION. PERFORMED REPAIR ON THE APU INLET DOOR CU (N33132)

All 953: https://openairdocs.org/jasc/4910/reports.md

## Other codes in chapter 49

- [JASC 4900](https://openairdocs.org/jasc/4900): Airborne Auxiliary Power Unit (APU) System (1,839 reports)
- [JASC 4920](https://openairdocs.org/jasc/4920): APU Core Engine (2,429 reports)
- [JASC 4930](https://openairdocs.org/jasc/4930): APU Engine Fuel and Control (1,087 reports)
- [JASC 4940](https://openairdocs.org/jasc/4940): APU Start/Ignition System (1,424 reports)
- [JASC 4950](https://openairdocs.org/jasc/4950): APU Bleed Air System (949 reports)
- [JASC 4960](https://openairdocs.org/jasc/4960): APU Controls (383 reports)
- [JASC 4970](https://openairdocs.org/jasc/4970): APU Indicating System (272 reports)
- [JASC 4980](https://openairdocs.org/jasc/4980): APU Exhaust System (164 reports)
- [JASC 4990](https://openairdocs.org/jasc/4990): APU Oil System (2,650 reports)
- [JASC 4997](https://openairdocs.org/jasc/4997): APU System Wiring (226 reports)

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