# STC SA2381NM

- Type: Supplemental type certificate
- Status: Current, Amended
- Holder: Knots 2U Ltd., United States
- Description: Installation of Knots 2U, Ltd Wheel and Body Fairings
- Applied: August 19, 2008
- Status date: August 19, 2008
- Product: Aircraft, Single-Engine
- Certification basis: Part 21
- Data sheets: [TCDS 3A12](https://openairdocs.org/tcds/3A12), [TCDS 3A13](https://openairdocs.org/tcds/3A13), [TCDS 3A17](https://openairdocs.org/tcds/3A17), [TCDS 3A19](https://openairdocs.org/tcds/3A19), [TCDS 3A21](https://openairdocs.org/tcds/3A21), [TCDS 3A24](https://openairdocs.org/tcds/3A24), [TCDS 5A6](https://openairdocs.org/tcds/5A6), [TCDS A13CE](https://openairdocs.org/tcds/A13CE), [TCDS A16CE](https://openairdocs.org/tcds/A16CE), [TCDS A4CE](https://openairdocs.org/tcds/A4CE)
- Certificate PDF: https://openairdocs.org/files/sha256/5d/5e/5d5e9e08889b5c620346ce464805236175ad37c23597c40f05bbb5cd4f6e3310
- Approved model list and other attachments: [SA2381NM.pdf](https://openairdocs.org/files/sha256/a1/46/a1464dfdec0b2fb4f1775dc5a686e968598a84970b9922706b19b88029b402a1)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/927C01C47646BD94862574DD0074F14E.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA2381NM

## ADs that name it (0)

None.

## Approved models (118, first 50)

- Cessna Aircraft Company 150 ([TCDS 3A19](https://openairdocs.org/tcds/3A19))
- Cessna Aircraft Company 150A ([TCDS 3A19](https://openairdocs.org/tcds/3A19))
- Cessna Aircraft Company 150B ([TCDS 3A19](https://openairdocs.org/tcds/3A19))
- Cessna Aircraft Company 150C ([TCDS 3A19](https://openairdocs.org/tcds/3A19))
- Cessna Aircraft Company 150D ([TCDS 3A19](https://openairdocs.org/tcds/3A19))
- Cessna Aircraft Company 150E ([TCDS 3A19](https://openairdocs.org/tcds/3A19))
- Cessna Aircraft Company 150F ([TCDS 3A19](https://openairdocs.org/tcds/3A19))
- Cessna Aircraft Company 150G ([TCDS 3A19](https://openairdocs.org/tcds/3A19))
- Cessna Aircraft Company 150H ([TCDS 3A19](https://openairdocs.org/tcds/3A19))
- Cessna Aircraft Company 150J ([TCDS 3A19](https://openairdocs.org/tcds/3A19))
- Cessna Aircraft Company 150K ([TCDS 3A19](https://openairdocs.org/tcds/3A19))
- Cessna Aircraft Company 150L ([TCDS 3A19](https://openairdocs.org/tcds/3A19))
- Cessna Aircraft Company 150M ([TCDS 3A19](https://openairdocs.org/tcds/3A19))
- Cessna Aircraft Company 152 ([TCDS 3A19](https://openairdocs.org/tcds/3A19))
- Cessna Aircraft Company 172 ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172A ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172B ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172C ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172D ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172E ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172F ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172F (USAF T-41A) ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172G ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172H ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172H (USAF T-41A) ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172I ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172K ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172L ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172M ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172N ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172P ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172Q ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172R ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 175 ([TCDS 3A17](https://openairdocs.org/tcds/3A17))
- Cessna Aircraft Company 175B ([TCDS 3A17](https://openairdocs.org/tcds/3A17))
- Cessna Aircraft Company 175C ([TCDS 3A17](https://openairdocs.org/tcds/3A17))
- Cessna Aircraft Company 177 ([TCDS A13CE](https://openairdocs.org/tcds/A13CE))
- Cessna Aircraft Company 177A ([TCDS A13CE](https://openairdocs.org/tcds/A13CE))
- Cessna Aircraft Company 177B ([TCDS A13CE](https://openairdocs.org/tcds/A13CE))
- Cessna Aircraft Company 180 ([TCDS 5A6](https://openairdocs.org/tcds/5A6))
- Cessna Aircraft Company 180A ([TCDS 5A6](https://openairdocs.org/tcds/5A6))
- Cessna Aircraft Company 180B ([TCDS 5A6](https://openairdocs.org/tcds/5A6))
- Cessna Aircraft Company 180C ([TCDS 5A6](https://openairdocs.org/tcds/5A6))
- Cessna Aircraft Company 180D ([TCDS 5A6](https://openairdocs.org/tcds/5A6))
- Cessna Aircraft Company 180E ([TCDS 5A6](https://openairdocs.org/tcds/5A6))
- Cessna Aircraft Company 180F ([TCDS 5A6](https://openairdocs.org/tcds/5A6))
- Cessna Aircraft Company 180G ([TCDS 5A6](https://openairdocs.org/tcds/5A6))
- Cessna Aircraft Company 180H ([TCDS 5A6](https://openairdocs.org/tcds/5A6))
- Cessna Aircraft Company 180J ([TCDS 5A6](https://openairdocs.org/tcds/5A6))
- Cessna Aircraft Company 180K ([TCDS 5A6](https://openairdocs.org/tcds/5A6))

All 118: https://openairdocs.org/stc/SA2381NM/models.md

## What the certificate says

Read from the PDF's text layer, without the form's printed wording; the layout is lost and the order can differ. The PDF is the record.

**FAA APPROVED MODEL LIST (AML) NO. SA2381M KNOTS 2U, LTD.**

INSTALLING WHEEL AND BODY FAIRINGS ISSUE DATE: 2/14/85

**ITEM**

**AIRCRAFT**

**AIRCRAFT**

**ORIGINAL TYPE**

**CERTIFICATION BASIS**

**INSTALLATION**

**INSTRUCTIONS**

AFM

AML

**MAKE MODEL CERTIFICATE NUMBER FOR**

**ALTERATION**

**NUMBER**

**REVISION NO. & DATE**

**SUPPLEMENT**

**NUMBER/DATE**

**AMENDMENT DATE**

Page 1 of 3 1 Cessna Aircraft Company 150, 150A, 150B, 150C, 150D, 150E, 150F, 150G, 150H, 150J, 150K, 150L, 150M, A150K, A150L, A150M, 152, A152 3A19 CAR 3 Installation Manual CNGF-M

Installation Manual CMGF-M Rev. A Dated 5/4/01

Rev. A Dated 5/4/01 N/A 8/19/08 2 Cessna Aircraft Company 172, 172A, 172B, 172C, 172D, 172E, 172F, 172G, 172H, 172I, 172K, 172L, 172M, 172N, 172P, 172Q 3A12 CAR 3 Installation Manual CNGF-M

Installation Manual CMGF-M

Installation Manual 172CBF-M Rev. A Dated 5/4/01

Rev. A Dated 5/4/01

Rev. A Dated 5/4/01 N/A 8/19/08 3 Cessna Aircraft Company 172R 3A12 FAR 23 Installation Manual CNGF-M

Installation Manual CMGF-M Rev. A Dated 5/4/01

Rev. A Dated 5/4/01 N/A 8/19/08 4 Cessna Aircraft Company 177, 177A, 177B A13CE FAR 23 Installation Manual CNGF-M

Installation Manual CMGF-M Rev. A Dated 5/4/01

Rev. A Dated 5/4/01 N/A 8/19/08 5 Cessna Aircraft Company 182, 182A, 182B, 182C, 182D, 182E, 182F, 182G, 182H, 182J, 182K, 182L, 182M, 182N, 182P, 182Q, 182R, T182 3A13 CAR 3 Installation Manual CNGF-M

Installation Manual CMGF-M

Installation Manual 182CBF-M Rev. A Dated 5/4/01

Rev. A Dated 5/4/01

Rev. A Dated 5/4/01 N/A 8/19/08 6 Cessna Aircraft Company 182S 3A13 FAR 23 Installation Manual CNGF-M

Installation Manual CMGF-M Rev. A Dated 5/4/01

Rev. A Dated 5/4/01 N/A 8/19/08

**FAA APPROVED MODEL LIST (AML) NO. SA2381M KNOTS 2U, LTD.**

INSTALLING WHEEL AND BODY FAIRINGS ISSUE DATE: 2/14/85

**ITEM**

**AIRCRAFT**

**AIRCRAFT**

**ORIGINAL TYPE**

**CERTIFICATION BASIS**

**INSTALLATION**

**INSTRUCTIONS**

AFM

AML

**MAKE MODEL CERTIFICATE NUMBER FOR**

**ALTERATION**

**NUMBER**

**REVISION NO. & DATE**

**SUPPLEMENT**

**NUMBER/DATE**

**AMENDMENT DATE**

Page 2 of 3 7 Cessna Aircraft Company 180, 180A, 180B, 180C, 180D, 180E, 180F, 180G, 180H, 180J, 180K 5A6 CAR 3 Installation Manual CMGF-M Rev. A Dated 5/4/01 N/A 8/19/08 8 Cessna Aircraft Company 185, 185A, 185B, 185C, 185D, 185E, A185E, A185F 3A24 CAR 3 Installation Manual CMGF-M Rev. A Dated 5/4/01 N/A 8/19/08 9 Cessna Aircraft Company 206, P206, P206A, P206B, P206C, P206D, P206E, U206, U206A, U206B, U206C, U206D, U206E, U206F, U206G, TP206A, TP206B, TP206C, TP206D, TP206E, TU206A, TU206B, TU206C, TU206D, TU206E, TU206F, TU206G A4CE CAR 3 Installation Manual CNGF-M

Installation Manual CMGF-M

Installation Manual 206CBF-M Rev. A Dated 5/4/01

Rev. A Dated 5/4/01

Rev. A Dated 5/4/01 N/A 8/19/08 10 Cessna Aircraft Company 206H, T206H A4CE FAR 23 Installation Manual CNGF-M

Installation Manual CMGF-M Rev. A Dated 5/4/01

Rev. A Dated 5/4/01 N/A 8/19/08 11 Cessna Aircraft Company 210-5, 210-5A 3A21 CAR 3 Installation Manual CNGF-M

Installation Manual CMGF-M Rev. A Dated 5/4/01

Rev. A Dated 5/4/01 N/A 8/19/08 12 Cessna Aircraft Company 207, 207A, T207, T207A A16CE FAR 23 Installation Manual CNGF-M

Installation Manual CMGF-M Rev. A Dated 5/4/01

Rev. A Dated 5/4/01 N/A 8/19/08

**FAA APPROVED MODEL LIST (AML) NO. SA2381M KNOTS 2U, LTD.**

INSTALLING WHEEL AND BODY FAIRINGS ISSUE DATE: 2/14/85

**ITEM**

**AIRCRAFT**

**AIRCRAFT**

**ORIGINAL TYPE**

**CERTIFICATION BASIS**

**INSTALLATION**

**INSTRUCTIONS**

AFM

AML

**MAKE MODEL CERTIFICATE NUMBER FOR**

**ALTERATION**

**NUMBER**

**REVISION NO. & DATE**

**SUPPLEMENT**

**NUMBER/DATE**

**AMENDMENT DATE**

Page 3 of 3 13 Cessna Aircraft Company P172D, R172K, 175, 175A, 175B, 175C 3A17 CAR 3 Installation Manual CNGF-M

Installation Manual CMGF-M Rev. A Dated 5/4/01

Rev. A Dated 5/4/01 N/A 8/19/08

FAA APPROVED:

Gregory J. Michalik, Senior Aerospace Engineer Airframe & Administrative Branch Chicago Aircraft Certification Office

Reissued: 5/13/99 Amended: 3/15/85, 3/31/86, 5/8/86, 8/19/08

Original signed by:

Gregory J. Michalik

### SA2381NM.pdf

United States of America Department of Transportation -- Federal Aviation Administration Supplemental Type Certificate

_____________________________________________________________________________________________________________________________________ Any alteration of this certificate is punishable by a fine of not exceeding $1,000, or imprisonment not exceeding 3 years, or both.

_____________________________________________________________________________________________________________________________________ FAA FORM 8110-2(10-68) PAGE 1 of 2 PAGES T his certificate may be transferred in accordance with FAR 21.47.

Number SA2381NM This certificate issued to

certifies that the change in the type design for the following product with the limitations and conditions therefor as specified hereon meets the airworthiness requirements of Part * of the * Regulations. *

Original Product--Type Certificate Number : *

Description of Type Design Change:

Installation of Knots 2U, Ltd Wheel and Body Fairings in accordance with Knots 2U, Ltd Installation Instructions as listed on AML SA2381NM, amended August 19, 2008, or later FAA approved revision.

Limitations and Conditions:

1. The installer must determine whether this design change is compatible with previously approved modifications. 2. A copy of this Certificate and FAA Approved Model List (AML) No. SA2381NM, amended August 19, 2008, or later FAA approved revisions, must be maintained as part of the permanent records for the modified aircraft. 3. The wheel and body fairings are to be inspected and maintained in accordance with Knots 2U, Ltd Installation Instructions as listed on AML No. SA2381NM, amended August 19, 2008, or later FAA approved revisions. 4. If the holder agrees to permit another person to use this certificate to alter a product, the holder must give the other person written evidence of that permission

This certificate and the supporting data which is the basis for approval shall remain in effect until surrendered, suspended, revoked or a termination date is otherwise established by the Administrator of the Federal Aviation Administration.

Knots 2U, Ltd 703 Airport Drive Burlington, WI 53105 * (see attached FAA Approved Model Make : * List (AML) No. SA2381NM for list of Model : * Approved models and applicable airworthiness regulations)

Date of application : November 16, 1983

Date of issuance : May 14, 1984

Date reissued : May 30, 1984; May 13, 1999

Date amended : February 14, 1985; March 15, 1985;

May 1, 1985; May 13,1999;

August 19, 2008

By direction of the Administrator

_______________________________________________________ ( Signature) Gregory J. Michalik, Senior Aerospace Engineer Airframe & Administrative Branch Chicago Aircraft Certification Office _______________________________________________________ ( Title) Original signed by:

Gregory J. Michalik

United States of America Department of Transportation - Federal Aviation Administration Supplemental Type Certificate (Continuation Sheet)

___________________________________________________________________________________________________________________________________ Any alteration of this certificate is punishable by a fine of not exceeding $1,000, or imprisonment not exceeding 3 years, or both.

___________________________________________________________________________________________________________________________________ FAA FORM 8110-2-1(10-69) PAGE 2 of 2 PAGES This certificate may be transferred in accordance with FAR 21.47.

Number

## Every issue (1)

- August 19, 2008: Amended, Current. [certificate](https://openairdocs.org/files/sha256/5d/5e/5d5e9e08889b5c620346ce464805236175ad37c23597c40f05bbb5cd4f6e3310), [SA2381NM.pdf](https://openairdocs.org/files/sha256/a1/46/a1464dfdec0b2fb4f1775dc5a686e968598a84970b9922706b19b88029b402a1)

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