# N25561: 1975 Continental Copters-Transworld TOM CAT MARK 5A

- Status: Valid registration
- Airframe: [Continental Copters-Transworld TOM CAT MARK 5A](https://openairdocs.org/model/continental-copters-transworld-tom-cat-mark-5a) (registry code 2390301, 3 seats)
- Engine: [Lycoming VO-435 series](https://openairdocs.org/engine/lycoming-vo-435-series) (registry code 41525)
- Data sheets: [TCDS H5SW](https://openairdocs.org/tcds/H5SW) (Scott's-Bell 47 Inc), [TCDS E-279](https://openairdocs.org/tcds/E-279) (Lycoming Engines) (OpenAirDocs)
- Serial number: TC-TWH-1
- Year built: 1975
- Type: Rotorcraft
- Engine type: Reciprocating
- Airworthiness: Restricted, agriculture and pest control
- Airworthiness date: April 2, 1992
- Certificate issued: May 18, 2011
- Expires: May 31, 2027
- Mode S code: A26D55
- Registered owner: [Hendrickson Flying Service Inc](https://openairdocs.org/faa-owner/HENDRICKSON%20FLYING%20SERVICE%20INC)
- Location: [Rochelle, IL](https://openairdocs.org/faa-place/IL/Rochelle)
- Owner type: Corporation
- Owner's area on the map: 41.9500° N, 89.0656° W: Placed by OpenAirDocs at the center of ZIP code 61068, within about 6 miles (OpenAirDocs). The owner's mailing address, not where the aircraft is based
- FAA registry: https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=25561
- Page: https://openairdocs.org/aircraft/N25561

From the FAA registry file of October 24, 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 VO-435 model are included.

## ADs that may apply (OpenAirDocs): 9 in force

### Matched by airframe (Continental Copters-Transworld TOM CAT MARK 5A)

None in force.

### Matched by engine (Lycoming VO-435 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 2022-16-03](https://openairdocs.org/ad/2022-16-03): Engine (RECIPROCATING) · Continental Aerospace Technologies GTSIO-520-C, GTSIO-520-D, GTSIO-520-F and 236 more. Effective Aug 15, 2022
- [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 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 80-04-04 R1](https://openairdocs.org/ad/80-04-04-R1): Crankshaft Flange Bolts · Lycoming Engines IVO-540-A1A, TIVO-540-A2A, TVO-435-A1A and 38 more. Effective Aug 18, 1980
- [AD 69-24-03](https://openairdocs.org/ad/69-24-03): Carburetors · Continental Motors A-65-1, A-65-12, A-65-12F and 321 more. Effective Nov 29, 1969
- [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 68-08-08](https://openairdocs.org/ad/68-08-08): Hydraulic Valve · Lycoming Engines IGSO-480-A1A6, IGSO-480-A1B6, IGSO-480-A1C6 and 44 more. Effective May 19, 1968

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

- [AD 2024-21-02](https://openairdocs.org/ad/2024-21-02) (historical): Engine (Reciprocating) · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 548 more. Effective Dec 5, 2024

## Information bulletins (advisory) (2 in force)

- [SAIB NE-19-08](https://openairdocs.org/saib/NE-19-08): Reciprocating Engine Cylinder Section - Lycoming Engines Parallel Valve Cylinders. Issued May 2, 2019
- [SAIB NE-14-13](https://openairdocs.org/saib/NE-14-13): Reciprocating Engine - Cylinder Mounting Studs. Issued Mar 24, 2014

## NTSB investigations (2)

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [NTSB NYC01LA130](https://openairdocs.org/ntsb/NYC01LA130), May 29, 2001: Continental Copters Tom Cat Mark 5A (N25561), Benton, PA, substantial damage. Probable cause: The pilot's inadequate preflight inspection, which resulted in a takeoff with a hose still attached and a subsequent dynamic rollover.
- [NTSB CHI88DEX11](https://openairdocs.org/ntsb/CHI88DEX11), Aug 10, 1988: Continental Copters MK-5 (N25561), Redkey, IN, destroyed, 1 fatal. Probable cause: PHYSICAL IMPAIRMENT OF THE PILOT DUE TO DRUGS WHICH RESULTED IN A MISJUDGED APPROACH AND SUBSEQUENT CONTACT WITH TREES DURING THE APPROACH TO AN AERIAL APPLICATION SWATH RUN.

## FAA accident and incident reports (2)

From the FAA Accident/Incident Data System. Reports are matched to registry aircraft by N-number and event date, checked against the reported make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [Accident 20010529017659A](https://openairdocs.org/incident/20010529017659A), May 29, 2001: Ccoptr TOMCATMK5A (N25561), Benton, PA, Substantial damage. (-23) In may 29, 2001, about 0718 eastern daylight time, a Continental copters tom cat mark 5A (a modified bel 47 helicopter), N25561, was substantially…
- [Accident 19880810033729A](https://openairdocs.org/incident/19880810033729A), Aug 10, 1988: Bell OH13HMK5A (N25561), Redkey, IN, Destroyed, 1 fatal. On a spray turn around, crashed after striking a tree. High level of medical drugs in pilot.

## 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) (23)

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 VO-435 series)

- [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 SE01954SE](https://openairdocs.org/stc/SE01954SE): Installation of engine crankcase seal. Ly-Con Rebuilding Company. Lists VO-435-A1A
- [STC SE01966WI](https://openairdocs.org/stc/SE01966WI): Use of GAMI G100UL High Octane Unleaded Avgas in spark ignition piston aircraft engines. General Aviation Modifications Inc. Lists VO-435-B1A
- [STC SE8628SW](https://openairdocs.org/stc/SE8628SW): Installation of oil nozzles for lubrication of cam and filters. Cygnet Aerospace Corp. Lists VO-435-A1A (O-435-21)
- [STC SE4408SW](https://openairdocs.org/stc/SE4408SW): Miscellaneous engine cylinder replacement parts. Continental Motors, Inc
- [STC SE7504SW](https://openairdocs.org/stc/SE7504SW): Installation of any or all parts listed on Airmotive Engineering Drawing List No. 852-1, Rev. 1, dated 10/4/88, or later FAA approved revision. Continental Motors, Inc
- [STC SE7665SW](https://openairdocs.org/stc/SE7665SW): Installation of parts listed on Airmotive List No. 8810-3, Rev 6. Continental Motors, Inc
- [STC SE8776SW](https://openairdocs.org/stc/SE8776SW): Installation of coated cylinders and piston rings. Continental Motors, Inc
- [STC SE2902NM](https://openairdocs.org/stc/SE2902NM): Lycoming valve cover gasket. Real Gaskets Tennessee. Lists VO-435-A1A (O-435-21)
- [STC SE144GL](https://openairdocs.org/stc/SE144GL): Modify engine to increase compression ratio to 8.7:1. Scott's Bell 47 Inc. Lists VO-435-A1F
- [STC SE2500SW](https://openairdocs.org/stc/SE2500SW): Modification to higher compression ratio. Scott's Bell 47 Inc. Lists VO-435-A1E
- [STC SE2733SW](https://openairdocs.org/stc/SE2733SW): Modification to higher compression ratio. Scott's Bell 47 Inc. Lists VO-435-A1E
- [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
- [STC SE00350SE](https://openairdocs.org/stc/SE00350SE): Installation of sump mounted chip detector. Aviation Development Corporation. Lists VO-435-A1A (O-435-21)
- [STC SE8023SW](https://openairdocs.org/stc/SE8023SW): Installation and usage of AEROSHELL. Shell Development Co
- [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 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 SE128NE](https://openairdocs.org/stc/SE128NE): Use of AMS/OIL 15W 50 synthetic piston aircraft oil in Avco engines. AMS/OIL
- [STC SE959EA](https://openairdocs.org/stc/SE959EA): Modification to higher compression ration. Agrotors, Inc. Lists VO-435-A1E
- [STC SE2-856](https://openairdocs.org/stc/SE2-856): American Bosch Induction vibrator VJR24B56X. Bell Helicopter Textron
- [STC SE44WE](https://openairdocs.org/stc/SE44WE): Use of Kling Aviation Oil, Specifications KL-100, KL-200 and KL-300 in Continental and Lycoming engines. Kling Oil Company

## Related

- Other Continental Copters-Transworld TOM CAT MARK 5A aircraft: https://openairdocs.org/model/continental-copters-transworld-tom-cat-mark-5a/aircraft.md
- The Lycoming VO-435 series engine: https://openairdocs.org/engine/lycoming-vo-435-series.md

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