# N321ML: 1991 Lamos Mark Allan THORPE T-18

- Status: Valid registration
- Airframe: [Lamos Mark Allan THORPE T-18](https://openairdocs.org/model/lamos-mark-allan-thorpe-t-18) (registry code 89510U4, 2 seats)
- Engine: [Lycoming 0-290 series](https://openairdocs.org/engine/lycoming-0-290-series) (registry code 41506)
- Data sheets: [TCDS E-229](https://openairdocs.org/tcds/E-229) (Lycoming Division AVCO Corporation) (OpenAirDocs)
- Serial number: 1042
- Year built: 1991
- Type: Fixed wing single engine
- Engine type: Reciprocating
- Airworthiness: Experimental, amateur built
- Airworthiness date: February 24, 1992
- Certificate issued: May 21, 2003
- Expires: September 30, 2027
- Mode S code: A37325
- Registered owner: [Salerno Lawrence B](https://openairdocs.org/faa-owner/SALERNO%20LAWRENCE%20B)
- Location: [St Charles, IL](https://openairdocs.org/faa-place/IL/St%20Charles)
- Owner type: Individual
- Owner's area on the map: 41.9482° N, 88.3887° W: Placed by OpenAirDocs at the center of ZIP code 60175, within about 3 miles (OpenAirDocs). The owner's mailing address, not where the aircraft is based
- FAA registry: https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=321ML
- Page: https://openairdocs.org/aircraft/N321ML

From the FAA registry file of October 22, 2026. ADs below are matched by the registry's airframe and engine model codes. They may apply; each AD's applicability can narrow it by serial number, part number or installed equipment. This is not a compliance determination. The registry lists only the engine series, so ADs for every Lycoming 0-290 model are included.

## ADs that may apply (OpenAirDocs): 10 in force

### Matched by airframe (Lamos Mark Allan THORPE T-18)

None in force.

### Matched by engine (Lycoming 0-290 series)

- [AD 2026-04-11](https://openairdocs.org/ad/2026-04-11): Engine (Reciprocating) · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 605 more. Effective Apr 8, 2026
- [AD 2012-03-07](https://openairdocs.org/ad/2012-03-07): Carburetor · Lycoming Engines GO-435, GO-435-C2 (O-435-17), GO-435-C2A and 389 more. Effective Mar 27, 2012
- [AD 2004-10-14](https://openairdocs.org/ad/2004-10-14): Crankshaft gear · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 642 more. Effective Jun 25, 2004
- [AD 98-17-11](https://openairdocs.org/ad/98-17-11): Crankshafts · Continental Motors A-65-3, A-65-8, A75-8 and 90 more. Effective Oct 19, 1998
- [AD 98-01-06](https://openairdocs.org/ad/98-01-06): Carburetors · Continental Motors A-65-1, A-65-12, A-65-12F and 184 more. Effective Feb 13, 1998
- [AD 93-19-04](https://openairdocs.org/ad/93-19-04): Carburetors · Continental Motors A-65-1, A-65-12, A-65-12F and 184 more. Effective Oct 18, 1993
- [AD 90-04-06 R1](https://openairdocs.org/ad/90-04-06-R1): Propeller Governor External Oil Line · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 427 more. Effective May 28, 1991
- [AD 75-08-09](https://openairdocs.org/ad/75-08-09): Oil Pump Drive Shaft · Lycoming Engines AEIO-360-A1B, AEIO-360-A1B6, AEIO-360-A1C and 365 more. Effective Aug 18, 1977
- [AD 66-06-03](https://openairdocs.org/ad/66-06-03): Connecting Rod Assemblies · Lycoming Engines GO-435-C2 (O-435-17), GO-435-C2A, GO-435-C2A2 and 317 more. Effective Jan 16, 1969
- [AD 54-02-01](https://openairdocs.org/ad/54-02-01): Magneto Timing · Textron Lycoming, AVCO O-290-D2

### Historical (superseded or no longer in force)

- [AD 81-18-04 R2](https://openairdocs.org/ad/81-18-04-R2) (historical): Engine Oil Pump Driven Impeller and Shaft · Textron Lycoming, AVCO AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 376 more. Effective Jun 7, 1982

## Information bulletins (advisory) (1 in force)

- [SAIB NE-01-22](https://openairdocs.org/saib/NE-01-22): . Issued May 11, 2001

## NTSB investigations

None matched to N321ML.

## FAA accident and incident reports

None matched to N321ML.

## Service difficulty reports

None filed for this aircraft. Matched to this aircraft by N-number and event date, checked against the reported serial number, make and model.

## STCs that may be installed (OpenAirDocs) (34)

Approved for this aircraft's airframe or engine model, in force first, then newest. The registry doesn't record which STCs an aircraft has; its records do.

### Approved for the engine (Lycoming 0-290 series)

- [STC SE04651CH](https://openairdocs.org/stc/SE04651CH): To allow use of l00R grade aviation fuel meeting Swift Fuel, LLC specification SPEC-l00R-22. Swift Fuels LLC
- [STC SE00825WI](https://openairdocs.org/stc/SE00825WI): Installation of Specialty Products Spin-on oil filter on Lycoming Engines. B & C Specialty Products Inc. Lists O-290-A
- [STC SE2932SW](https://openairdocs.org/stc/SE2932SW): Install carburetor air temperature indicator. Approved for Aircooled Motors (Franklin Engine Co.) equipped with float carburetors. Model eligibility included here may not be inclusive. Alcor LLC
- [STC SE208SO](https://openairdocs.org/stc/SE208SO): Installation of ice indicator in the carburetor. LegacySTC.com
- [STC SE04349CH](https://openairdocs.org/stc/SE04349CH): Installation of SureFly electronic ignition. SureFly Partners Ltd
- [STC SE01954SE](https://openairdocs.org/stc/SE01954SE): Installation of engine crankcase seal. Ly-Con Rebuilding Company
- [STC SE00939WI](https://openairdocs.org/stc/SE00939WI): Installation of B&C Specialty Products Model BC 315-( ) Starter on Lycoming engines. B & C Specialty Products Inc
- [STC SE2392CE](https://openairdocs.org/stc/SE2392CE): Installation of B&C Speciality Products lightweight (10.2 pounds) engine starter, part number BC-315-100-1 (12 volts) or part number BC-315-100-3 (24 volts). B & C Specialty Products Inc. Lists O-290-D
- [STC SE03232CH](https://openairdocs.org/stc/SE03232CH): Installation of Engine Preheat Kit p/n TA2925-1 for 115 volt application. Hartzell Propeller Inc
- [STC SE04577CH](https://openairdocs.org/stc/SE04577CH): Install an electronic engine ignition system. Electroair Acquisition Corp. Lists O-290-A
- [STC SE8628SW](https://openairdocs.org/stc/SE8628SW): Installation of oil nozzles for lubrication of cam and filters. Cygnet Aerospace Corp. Lists O-290-D
- [STC SE8776SW](https://openairdocs.org/stc/SE8776SW): Installation of coated cylinders and piston rings. Continental Motors, Inc
- [STC SE00218NY](https://openairdocs.org/stc/SE00218NY): Replacement of Lycoming starter with SKY-TEC 12 volt starter installed. Hartzell Engine Technologies, LLC
- [STC SE00226NY](https://openairdocs.org/stc/SE00226NY): Replacement of Lycoming starter with SKY-TEC 24-volt starter Models 149-24HT and 122-24HT. Approval limited to 24-volt DC source available to the starter. Hartzell Engine Technologies, LLC
- [STC SE00357NY](https://openairdocs.org/stc/SE00357NY): Replacement of Lycoming starter with SKY-TEC 24-volt starter installed. Hartzell Engine Technologies, LLC
- [STC SE2901NM](https://openairdocs.org/stc/SE2901NM): Lycoming valve cover gasket. Real Gaskets Tennessee
- [STC SE01930NY](https://openairdocs.org/stc/SE01930NY): Installation of Casper Labs 90 degree oil filter housing adapter. Casper Labs Inc
- [STC SE01943CH](https://openairdocs.org/stc/SE01943CH): Add the following approved fuels: unleaded automotive gasoline 87 minimum antiknock index, per ASTM Specification D-439 or D-4814 of any volatility class, A through E, or 82UL AVGAS per ASTM D-6227. Experimental Aircraft Association Inc
- [STC SE1779NM](https://openairdocs.org/stc/SE1779NM): Installation of Precise Flight, Inc. Standby Vacuum System SVS III. Precise Flight Inc
- [STC SE5743NM](https://openairdocs.org/stc/SE5743NM): Intallation of adapter for externally mounted oil filter. Aviation Development Corporation
- [STC SE1-201](https://openairdocs.org/stc/SE1-201): Installation of the Richter Aero Equipment Type B-4 or B-5 Temperature Probe. (O-360 SERIES (excl. A1C, C2B, C2D)). MidContinent Instru Co Inc
- [STC SE09492SC](https://openairdocs.org/stc/SE09492SC): Installation and usage of Exxon 20W50 multigrade aircraft engine oil conforming to Exxon Oil formulation WS-3013. Exxon Company USA. Lists O-290-D
- [STC SE00350SE](https://openairdocs.org/stc/SE00350SE): Installation of sump mounted chip detector. Aviation Development Corporation
- [STC SE5173NM](https://openairdocs.org/stc/SE5173NM): Installation of a replacement oil cooler adaptor, P/N ADC-310. Aviation Development Corporation
- [STC SE8023SW](https://openairdocs.org/stc/SE8023SW): Installation and usage of AEROSHELL. Shell Development Co
- [STC SA2392CE](https://openairdocs.org/stc/SA2392CE): Installation of B & C Specialty Products. Bainbridge William C III. Lists O-290-D
- [STC SE452NE](https://openairdocs.org/stc/SE452NE): Installation and usage of 'Mobil AV 1' aviation oil. Mobil Research & Development Corp
- [STC SE5879SW](https://openairdocs.org/stc/SE5879SW): Use of Phillips X/C II 20W-50 and25W-60 oil (OSS 55875) in all Avco reciprocating aircraft engines from 65 to 450 BHP. Phillips Petroleum Co
- [STC SE5924SW](https://openairdocs.org/stc/SE5924SW): Installation of stainless steel replacement exhaust studs on AVCO engines. Perrigo & Steele Aircraft Engr Company
- [STC SE2036CE](https://openairdocs.org/stc/SE2036CE): Add the following approved fuel: unleaded automotive gasoline, 87 minimum antiknock index, and leaded automotive gasoline, 88 minimum antiknock index(RON+MON)/2. Intermixing with aviation gasoline also approved. Petersen Aviation Inc. Lists O-290-A
- [STC SE80NE](https://openairdocs.org/stc/SE80NE): Installation and usage of Bel-Ray synthetic aviation oil, Bel-Ray Aero 1, (nonsupercharged), horizontally opposed direct drive, aircraft engines of 350 hp. or less. Bel-Ray Company, Inc
- [STC SE1445SO](https://openairdocs.org/stc/SE1445SO): Use of Aero-blend oil additive in Teledyne (non turbocharged) aircraft engines. ProTec
- [STC SE128NE](https://openairdocs.org/stc/SE128NE): Use of AMS/OIL 15W 50 synthetic piston aircraft oil in Avco engines. AMS/OIL
- [STC SE5CE](https://openairdocs.org/stc/SE5CE): Prestolite ALK-5001 alternator. Larsen Industries

## Related

- Other Lamos Mark Allan THORPE T-18 aircraft: https://openairdocs.org/model/lamos-mark-allan-thorpe-t-18/aircraft.md
- The Lycoming 0-290 series engine: https://openairdocs.org/engine/lycoming-0-290-series.md

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