# JASC 7820: Engine Noise Suppressor - Type: JASC system/component code (FAA) - ATA chapter: 78 Engine Exhaust - Title in the code table: ENGINE NOISE SUPPRESSOR - Service difficulty reports: 248 - FAA code table: https://www.faa.gov/sites/faa.gov/files/JASC_Code.pdf#page=68 - Page: https://openairdocs.org/jasc/7820 ## What it covers For general reports of muffler system defects. The component used on reciprocating engines to reduce engine exhaust noise. Does not include the shroud over the muffler used to collect heated fresh air for cabin and carburetor heat filed in JASC code 2140. Includes the clover leaf shaped unit mounted on turbo-jet engine exhaust tailpipes for sound suppression. Typical parts are baffle, and flame tube, etc. ## Service difficulty reports (248, newest 50) - [SDR HNAA2026070200564](https://openairdocs.org/sdr/HNAA2026070200564), Jul 1, 2026: Emb EMB145LR. CLAMP. LOOSE. EXHAUST FUMES STRONGLY SMELLED IN COCKPIT DUIRNG APU AND PACKS RUNNING AFTER LANDING. FOUND MUFFLER CLAMPS LOOSE IN APU (N660CL) - [SDR 2025FA0000671](https://openairdocs.org/sdr/2025FA0000671), Sep 30, 2025: Tecnam P2006T. MUFFLER. OUT OF POSITION. MUFFLER FLANGE GOING TO NR 4 CYLINDER EXHAUST PIPE DOES NOT MATE ALL THE WAY DUE TO INTERFERENCE OF TUBES GOING TO THE A (N274TA) - [SDR 2024FA0000773](https://openairdocs.org/sdr/2024FA0000773), Oct 3, 2024: Piper PA44180. MUFFLER. CRACKED. L/H ENGINE RUNNING ROUGH AT HIGHER POWER SETTINGS. EGT WAS 300-400 DEGREES HIGHER THAN NORMAL. L/H ENGINE RUNNING ROUGH (N280AG) - [SDR 2024FA0000734](https://openairdocs.org/sdr/2024FA0000734), Aug 11, 2024: Mooney M20D. MUFFLER. FAILED. AFTER 3.5 HRS POST EXHAUST SYSTEM OVERHAUL, THE MUFFLER HAD A CATASTROPHIC FAILURE WHERE SECTION OF MUFFLER DEPARTED ASS (N1925Y) - [SDR 7RKR2024043001](https://openairdocs.org/sdr/7RKR2024043001), Apr 29, 2024: Cessna 310R. MUFFLER. SEPARATED. DURING VISUAL INSPECTION PRIOR TO MAINTENANCE RH MUFFLER OF LH ENGINE WAS FOUND TO BE COMPLETELY SEPARATED FROM FORWARD (N1274G) - [SDR 2024FA0000774](https://openairdocs.org/sdr/2024FA0000774), Mar 13, 2024: Piper PA44180. MUFFLER. CRACKED. R/H ENGINE DOES NOT DEVELOP FULL POWER. REMOVED DISASSEMBLED AND INSPECTED R/H AND L/H MAGNETOS PN: 4330, SN: 19121021 A (N278AG) - [SDR 2023FA0000601](https://openairdocs.org/sdr/2023FA0000601), Oct 17, 2023: Robsin R44RAVENII. MUFFLER. DISTORTED. EXHAUST SYSTEM HEAT DEFORMING. NEW MUFFLER SYSTEM INSTALLED @ 449.94 THEN AGAIN @912.12. (N654SA) - [SDR YV3R2023100200580](https://openairdocs.org/sdr/YV3R2023100200580), Aug 29, 2023: Robsin R44RAVENII. SHIELD. CRACKED. CUSTOMER REPORTED SHIELD ASSEMBLY P/N: D314-2 WAS FOUND CRACKED. - [SDR FQAR20200916008](https://openairdocs.org/sdr/FQAR20200916008), Sep 13, 2020: Piper PA28181. MUFFLER. DEFORMED. DURING AN INSPECTION BOTH MUFFLERS WERE FOUND WITH HEAT DEFORMATIONS UNDER THE CABIN HEAT SHROUD. (N545MA) - [SDR FQAR20200916009](https://openairdocs.org/sdr/FQAR20200916009), Sep 5, 2020: Piper PA28181. MUFFLER. DEFORMED. DURING AN INSPECTION BOTH MUFFLERS WERE FOUND WITH HEAT DEFORMATIONS UNDER THE CABIN HEAT SHROUD. (N746PA) - [SDR 2020FA0000373](https://openairdocs.org/sdr/2020FA0000373), Aug 17, 2020: Cessna 172S. MUFFLER. CRACKED. 99.7 HOURS SINCE NEW MUFFLER WAS INSTALLED, NEW MUFFLER HAS 2 INCH CRACK BETWEEN THE NUMBER 2 AND 4 RISER INLETS (N5262Y) - [SDR 2020FA0000275](https://openairdocs.org/sdr/2020FA0000275), Jun 2, 2020: Czawsp SPORTCRUISER. MUFFLER. CRACKED. CRACKED MUFFLER, ALONG THE WELD FOR INTAKE RISER. (N119BF) - [SDR 2020FA0000269](https://openairdocs.org/sdr/2020FA0000269), May 29, 2020: Czawsp SPORTCRUISER. MUFFLER. CRACKED. MUFFLER HAS 1" CRACK ALONG WELD AT INLET RISER, VERIFIED BY PRESSURE TEST. (N627SX) - [SDR 2020FA0000268](https://openairdocs.org/sdr/2020FA0000268), May 29, 2020: Czawsp SPORTCRUISER. MUFFLER. CRACKED. MUFFLER HAS 1" CRACK ALONG WELD AT INLET RISER, VERIFIED BY PRESSURE TEST. (N707SX) - [SDR 2020FA0000267](https://openairdocs.org/sdr/2020FA0000267), May 29, 2020: Czawsp SPORTCRUISER. MUFFLER. CRACKED. MUFFLER HAS 1" CRACK ALONG WELD NEAR RISER, VERIFIED BY PRESSURE TEST. (N485SC) - [SDR 2020FA0000266](https://openairdocs.org/sdr/2020FA0000266), May 29, 2020: Czawsp SPORTCRUISER. MUFFLER. CRACKED. MUFFLER HAS 1 INCH CRACK NEAR RISER ALONG THE WELD, VERIFIED BY PRESSURE TEST. (N287SC) - [SDR 2020FA0000265](https://openairdocs.org/sdr/2020FA0000265), May 28, 2020: Czawsp SPORTCRUISER. MUFFLER. CRACKED. MUFFLER CRACKED 1" LONG ALONG WELD FOR NR 1 CYLINDER RISER PIPE ON MUFFLER SIDE OF SLIP JOINT. (N154BF) - [SDR 2020FA0000272](https://openairdocs.org/sdr/2020FA0000272), Feb 27, 2020: Czawsp SPORTCRUISER. MUFFLER. CRACKED. MUFFLER CRACKED ALONG WELD FOR INLET PIPE ON ENDCAP. (N370SC) - [SDR 2020FA0000185](https://openairdocs.org/sdr/2020FA0000185), Feb 27, 2020: Piper PA28181. MUFFLER. CRACKED. CREW RECEIVED CO WARNING IN FLIGHT. THEY MADE A PRECAUTIONARY LANDING. UPON VISUAL INSPECTION OF EXHAUST SYSTEM FOUND CR (N704ND) - [SDR 2020FA0000271](https://openairdocs.org/sdr/2020FA0000271), Feb 11, 2020: Czawsp SPORTCRUISER. MUFFLER. CRACKED. MUFFLER CRACKED ALONG THE WELD FOR THE INLET PIPE ON ENDCAP, (N134BF) - [SDR 2020FA0000095](https://openairdocs.org/sdr/2020FA0000095), Jan 29, 2020: Cessna 172N. MUFFLER. CRACKED. PILOT SMELLED BURNING OIL IN CABIN, TURNED OFF CABIN HEAT AND SMELL WENT AWAY. INSPECTION FOUND MUFFLER CRACKED AT TAILP (N733TP) - [SDR FQAR2018060500031](https://openairdocs.org/sdr/FQAR2018060500031), May 14, 2018: Piper PA28181. MUFFLER. DAMAGED. DURING INSPECTION FOR POWER LOSS, FOUND BOTH MUFFLERS TO HAVE DAMAGED FLAME TUBES, WITH PIECES OF THE FLAME TUBE OBSTRUC (N329PA) - [SDR 2018FA0000350](https://openairdocs.org/sdr/2018FA0000350), Feb 18, 2018: Piper PA28140. MUFFLER. ERODED. DURING AN ANNUAL INSPECTION OF AN AIRCRAFT THAT HAD ACCUMULATED 300 HOURS SINCE THE INSTALLATION OF SUPPLEMENTAL TYPE CE (N56821) - [SDR 2017FA0000513](https://openairdocs.org/sdr/2017FA0000513), Oct 16, 2017: Bbavia 7KCAB. MUFFLER. DETACHED. AFTER TAKE OFF, A LOUD NOISE WAS HEARD IN THE COCKPIT. THE PILOT LANDED SAFELY AND ON INSPECTION, FOUND THE MUFFLER HAD (N11659) - [SDR 2017FA0000483](https://openairdocs.org/sdr/2017FA0000483), Sep 8, 2017: Robsin R44RAVENII. MUFFLER. CRACKED. DURING INSPECTION, FOUND THE MUFFLER ASSEMBLY CRACKED AND BULGING AT THE MATING FLANGES TO THE COLLECTORS AND THE WELDED (N442BD) - [SDR 2017FA0000003](https://openairdocs.org/sdr/2017FA0000003), Dec 30, 2016: Cessna 525. ATTENUATOR. DEPLOYED. PLANE TOOK OFF FROM KTRK IN DIRECTION TO KYVR, WHILE IN FLIGHT RIGHT HAND THRUST ATTENUATOR DEPLOYED, THE FLIGHT WAS DIV (N547TW) - [SDR EPUA20160521001](https://openairdocs.org/sdr/EPUA20160521001), May 21, 2016: Cessna 207A. MUFFLER. CONTAMINATED. DURING TAKEOFF, PILOT REPORTS OF BURNING PLASTIC SMELL. INSPECTED ACFT & FOUND MELTED PLASTIC ON LT MUFFLER. IT IS BELIE (N9948M) - [SDR FQAR20160421019](https://openairdocs.org/sdr/FQAR20160421019), Apr 21, 2016: Piper PA44180. MUFFLER. CRACKED. DURING REPLACEMENT OF THE RT ENGINE NR 3 EXHAUST RISER, THE TECH REMOVED THE AFT MUFFLER. NOTED THE MUFFLER HAD A LARGE, (N434PA) - [SDR OG5S2016FA0000139](https://openairdocs.org/sdr/OG5S2016FA0000139), Mar 22, 2016: Cessna 172S. MUFFLER. CRACKED. MUFFLER CRACKED INTERNALLY ALLOWING EXHAUST GASES TO ENTER HEATING SHROUD, THEREBY ALLOWING FUMES INTO CABIN. (N546ND) - [SDR CA160211007](https://openairdocs.org/sdr/CA160211007), Feb 11, 2016: Cessna 152. MUFFLER. BURNED. (CAN) WHILE AME WAS DOING MORNING SERVICING OF ACFT BEFORE BEING REMOVED FROM HANGAR NOTICED DISCOLORATION ON END OF TAI - [SDR OG5R2016FA0000046](https://openairdocs.org/sdr/OG5R2016FA0000046), Feb 2, 2016: Cessna 172S. MUFFLER. CRACKED. CRACKED MUFFLER ALLOWING EXHAUST FUMES TO ENTER THE CABIN. (N521ND) - [SDR CA151007015](https://openairdocs.org/sdr/CA151007015), Oct 2, 2015: Cessna A185F. SHROUD. BROKEN. (CAN) PILOTS NOTED BANGING NOISE COMING FROM ENGINE AT LOW IDLE. ENGINE SHUTDOWN, COWLING WAS REMOVED. HEAT MUFFLER SHRO - [SDR CA150930005](https://openairdocs.org/sdr/CA150930005), Sep 28, 2015: Piper PA44180. MUFFLER. BLOCKED. (CAN) THE PILOTS REPORTED THAT THE RT ENGINE WAS RUNNING ROUGH IN CRUISE FLIGHT. MAINTENANCE FOUND THAT THE RT ENGINE FO - [SDR 2015FA0000265](https://openairdocs.org/sdr/2015FA0000265), Jun 10, 2015: Cessna 172S. MUFFLER. CRACKED. SPOT WELDS FAILED CAUSING CARBON MONOXIDE TO ENTER HEAT SHROUD THEREFORE ENTERING CABIN. (N572ND) - [SDR OG5S2015FA0000238](https://openairdocs.org/sdr/OG5S2015FA0000238), May 27, 2015: Cessna 172S. MUFFLER. CRACKED. MUFFLER IS CRACKED INTERNALY AND SPOT WELDS HAVE BROKEN, ALLOWING CARBON MONOXIDE TO BE RELEASED INTO HEAT SHROUD AND IN (N564ND) - [SDR OG5S2015FA0000237](https://openairdocs.org/sdr/OG5S2015FA0000237), May 27, 2015: Cessna 172S. MUFFLER. CRACKED. SPOT WELDS IN MUFFLER CAN LET LOOSE, LETTING CARBON MONOXIDE INTO CABIN HEAT DUCT. (N511ND) - [SDR OG5R2015FA0000200](https://openairdocs.org/sdr/OG5R2015FA0000200), May 13, 2015: Cessna 172S. MUFFLER. FAILED. DURING FLIGHT CARBON MONOXIDE WARNING ILLUMINATED. PILOT RETURNED TO LAND. MAINTENANCE DISCOVERED 2 SPOTWELDS ON THE SHR (N539ND) - [SDR OG5S2015FA0000187](https://openairdocs.org/sdr/OG5S2015FA0000187), May 9, 2015: Cessna 172S. MUFFLER. CRACKED. SITTING ON THE RAMP IDLING, RECEIVED A HIGH CO2 WARNING AFTER A COUPLE ON MINUTES. SHUTDOWN ENGINE AND CO2 WARNING CEASE (N567ND) - [SDR OG5S2015FA0000180](https://openairdocs.org/sdr/OG5S2015FA0000180), May 7, 2015: Cessna 172S. MUFFLER. FAILED. DURING ROUTINE INSPECTION NOTED THAT 2 SPOTWELDS ON THE SHROUD SUPPORT FLANGE OF THE MUFFLER CAN HAD FAILED RESULTING IN (N563ND) - [SDR 2015FA0000161](https://openairdocs.org/sdr/2015FA0000161), Apr 22, 2015: Cessna 172S. MUFFLER. FAILED. ON TAKEOFF PILOT GOT A CARBON MONOXIDE WARNING ON PRIMARY FLIGHT DISPLAY. RETURNED AND LANDED WITHOUT INCIDENT. MAINTENA (N512ND) - [SDR CA150602022](https://openairdocs.org/sdr/CA150602022), Apr 15, 2015: Grob G115. MUFFLER. CRACKED. (CAN) LEFT MUFFLER CRACKED SHORTLY AFTER TAKEOFF. AN IMPACT AGAINST AIRFRAME WAS HEARD. A NORMAL CIRCUIT WAS COMPLETED A - [SDR OG5R2015040600123](https://openairdocs.org/sdr/OG5R2015040600123), Apr 6, 2015: Cessna 172S. MUFFLER. CRACKED. SPOT WELDS ON MUFFLER SEPARATED RELEASING EXHAUST INTO HEAT EXCHANGER. (N515ND) - [SDR 2015FA0000117](https://openairdocs.org/sdr/2015FA0000117), Apr 1, 2015: Tecnam P2006T. MUFFLER. DETERIORATED. ON COMPLYING WITH AD2015-02-09, FOUND EXHAUST PIPES LEAKING AT THE BALL JOINTS WHERE THEY CONNECT TO THE MUFFLER. 1 SIDE (N245TA) - [SDR NJ5R2015FA0000198](https://openairdocs.org/sdr/NJ5R2015FA0000198), Feb 19, 2015: Cessna 182T. BAFFLE. WARPED. FORWARD MUFFLER BAFFLE ON MUFFLER SYSTEM IS WARPED AND DISTORTED AFTER 199 HRS IN SERVICE. BAFFLE MATERIAL IS TOO THIN F (N632MR) - [SDR 2014FA0000657](https://openairdocs.org/sdr/2014FA0000657), Nov 12, 2014: Diamon DA40. MUFFLER. FAILED. MUFFLER DISTORTED, BURNED THROUGH IN TAILPIPE AREA, INSIDE HEATER MUFF. (N232BB) - [SDR 2014FA0000712](https://openairdocs.org/sdr/2014FA0000712), Nov 3, 2014: Cubcft CC18180. MUFFLER. CRACKED. DURING ANNUAL INSPECTION FOUND MUFFLER END WHERE RISER ATTACHES TO BE BROKEN/CRACKED. FURTHER EXAMINATION FOUND RISER CR (N232L) - [SDR EPUA201410082014](https://openairdocs.org/sdr/EPUA201410082014), Oct 7, 2014: Cessna 207A. MUFFLER. LEAKING. PILOT REPORTED EXHAUST SMELL IN CABIN. REPLACED THE MUFFLER, MUFFLER SHROUD & OPERATIONALLY CHECKED HEAT SYS ON GND WITH (N9869M) - [SDR CA150319006](https://openairdocs.org/sdr/CA150319006), Oct 5, 2014: Cessna 150G. MUFFLER. CRACKED. (CAN) CRACK IN THE INTERIOR OF THE RT MUFFLER FOUND DURING ANNUAL ENGINE INSPECTION. NEW MUFFLER TO BE INSTALLED. - [SDR CA140908026](https://openairdocs.org/sdr/CA140908026), Sep 5, 2014: Piper PA28140. OUTLET. ERODED. (CAN) DURING ROUTINE INSPECTION IT WAS DISCOVERED THAT THE MUFFLER OUTLET PIPE HAD AN EXTENSION PIECE THAT APPEARS TO BE - [SDR 2014FA0000452](https://openairdocs.org/sdr/2014FA0000452), Jul 28, 2014: Piper PA28180. MUFFLER. BLOCKED. THE FORWARD MUFFLER WAS REMOVED FROM THE NR 1 AND NR 2 CYLINDERS. THE INTERIOR SURFACES OF THE LT AND RT RISERS REVEALED (N4931L) All 248: https://openairdocs.org/jasc/7820/reports.md ## Other codes in chapter 78 - [JASC 7800](https://openairdocs.org/jasc/7800): Engine Exhaust System (281 reports) - [JASC 7810](https://openairdocs.org/jasc/7810): Engine Collector/Tailpipe/Nozzle (1,898 reports) - [JASC 7830](https://openairdocs.org/jasc/7830): Engine Thrust Reverser (5,902 reports) - [JASC 7897](https://openairdocs.org/jasc/7897): Engine Exhaust System Wiring (94 reports) --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.