# STC SA3659WE

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Northrop Grumman Systems Corporation, United States
- Description: Installation of Litton LTN-72R INS/RNAV and/or LTN-72 INS navigation systems in a triple configuration
- Applied: October 13, 1977
- Status date: April 12, 2016
- Product: Aircraft, Large Airplane
- Certification basis: Part 21, Part 25
- Data sheets: [TCDS A20WE](https://openairdocs.org/tcds/A20WE)
- Certificate PDF: https://openairdocs.org/files/sha256/1a/2b/1a2b0510cb2826b9b992c36d3b1b641577e55b8ce642463768af0968ef2be65a
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/5BE3309CEEC81C6B86257FA2006E552E.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA3659WE

## ADs that name it (0)

None.

## Approved models (1)

- The Boeing Company 747-200 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.

(See Type Certificate Data Sheet No. A20WE dated May 1, 1977) Original Product Type Certificate Number :

A20WE

Boeing Company

747-200 Series Description of Type Design Change : Installation of Litton LTN-72R INS/RNAV and/or LTN -72 INS navigation systems in a triple configuration in accordance with FAA sealed Litton Top installation Drawing No. 454065- 01 “B” revision dated May 17, 1978, or later sealed revision. Litton Airplane Flight Manual Supplement No. APD 2-78, dated June 20, 1978, or later approved revision are required with this modification.

Limitations and Conditions: The approval of this change in Type Design applies only to Boeing Model 747-200 series airplanes only . This approval should not be extended to other aircraft of this model on which other approved previously approved modifications are incorporated unless it is found by the installer 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 : October 13, 1977

Date of issuance : June 21, 1978

Date reissued : April 12, 2016

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

## Every issue (2)

- April 12, 2016: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/1a/2b/1a2b0510cb2826b9b992c36d3b1b641577e55b8ce642463768af0968ef2be65a)
- June 21, 1978: Issued, Historical. [certificate](https://openairdocs.org/files/sha256/b9/83/b98381e3bb40e35c4cd67c7bb2f8d29429174dc0158296e101585d82313c6a63)

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