# STC ST00246LA

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Northrop Grumman Systems Corporation, United States
- Description: Installation of Litton Triple LTN-92 Inertial Navigation Systems (INS) and dual LTN-2001 Global Positioning Sensors (GPS).
- Applied: March 11, 1996
- Status date: February 22, 2016
- Product: Aircraft, Large Multi-Engine
- Certification basis: Part 21, Part 25
- Data sheets: [TCDS A20WE](https://openairdocs.org/tcds/A20WE)
- Certificate PDF: https://openairdocs.org/files/sha256/51/ff/51ff4ef81910a6545d9f50e4a5621cd131450e011d345dcfc36866bf47f30cad
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/A55325181B79532786257F6B00667B7C.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/ST00246LA

## ADs that name it (0)

None.

## Approved models (2)

- The Boeing Company 747-200B Series ([TCDS A20WE](https://openairdocs.org/tcds/A20WE))
- The Boeing Company 747-300 Series ([TCDS A20WE](https://openairdocs.org/tcds/A20WE))

## 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.

This Certificate issued to Northrop Grumman Systems Corporation 21240 Burbank Blvd.

Woodland Hills, CA 91367-6675 Part 25* of the Federal Aviation Regulations.

(For Certification Basis see T. C. Data Sheet No. A20WE.)

A20WE

The Boeing Company

747-200B Series, 747-300 Series Description of Type Design Change: Installation of Litton Triple LTN-92 Inertial Navigation Systems (INS) and Dual LTN-2001 Global Positioning Sensors (GPS) in accordance with FAA approved Top Installation Drawing No. 454065-11, Revision “A”, dated May 30, 1996, or later FAA approved revision.

Litton Airplane Flight Manual Supplement, Document No. 464095, Revision “N/C”, FAA approved on July 8, 1996, or later FAA approved revision, is required as part of this installation.

Limitations and Conditions: The approval of this modification applies to the above noted aircraft model series only. This approval should not be extended to other aircraft of this model series on which other approved modifications are incorporated unless it is determined that the interrelationship between this change and any of those previously approved modifications will introduce no adverse effect upon the airworthiness of the aircraft. If the holder agrees to permit another person to use this certificate to alter the product, the holder shall give the other person written evidence of that permission.

Date of application : March 11, 1996

Date of issuance : July 8, 1996

Date reissued : March 30, 2015, February 22, 2016

Date amended : August 19, 1996, October 2, 1997

(Signature) Supervisor, Technical & Administrative Support Staff Los Angeles Aircraft Certification Office (Title)

## Every issue (2)

- February 22, 2016: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/51/ff/51ff4ef81910a6545d9f50e4a5621cd131450e011d345dcfc36866bf47f30cad)
- March 30, 2015: Reissued, Historical. [certificate](https://openairdocs.org/files/sha256/1d/4e/1d4e1b3757963f6f7880222da7aa8bffe6be0bbf8eea75810938ed23e9779329)

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