# STC SA2560NM

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: MIT Lincoln Laboratory, United States
- Description: Installation of auxiliary power unit, two air cycle machines and optical viewport.
- Applied: June 20, 1984
- Status date: February 14, 2017
- Product: Aircraft, Small Airplane
- Certification basis: Part 3, Part 21
- Data sheets: [TCDS A9EA](https://openairdocs.org/tcds/A9EA)
- Certificate PDF: https://openairdocs.org/files/sha256/8d/62/8d62cbbd840f0da54253388889f70ac518d57009606c1bed1b0ea0b4082c7e9b
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/205E7E16A2257E1E862580D5005B852B.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA2560NM

## ADs that name it (0)

None.

## Approved models (1)

- Viking Air Limited DHC-6-300 ([TCDS A9EA](https://openairdocs.org/tcds/A9EA))

## 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 MIT Lincoln Laboratory 244 Wood Street Lexington, MA 02420-9108 Part 3* of the Civil Air Regulations. *Certification basis is set forth in Type Certificate Data Sheet A9EA, Revision 6 Original Product Type Certificate Number :

A9EA de Havilland (Twin Otter) DHC-6 300, Serial Number 423 – One Only Description of Type Design Change: Installation of auxiliary power unit, two air cycle machines and optical viewport in accordance with FAA sealed Aero Union Corporation Drawing List No.

10040, Revision P, dated January 22, 1985, and FAA sealed Engineering Change Order Record, Revision C, dated May 10, 1985, or later FAA sealed revisions. FAA approved Aero Union Corporation Airplane Flight Manual Supplement dated July 22, 1985, or later FAA approved revision is required as part of this installation.

Limitations and Conditions : The above modification is approved for installation in de Havilland DHC-6, Model 300, Serial Number 423 only. No additional modification of this type are to be approved solely by reference to this Supplemental Type Certificate or to the data submitted therefore. A copy of this STC must be included in the permanent records of the modified aircraft.

Date of application : June 20, 1984

Date of issuance : July 23, 1985

Date reissued : April 15, 2015, February 14, 2017

(Signature) Steve Bogucki Manager, Technical and Administrative Support Staff

N umber SA2560NM

The conditions and limitations of Type Certificate A9EA apply except as outlined below:

de Havilland (Twin Otter) DHC-6 Model 300, Serial Number 423

Airspeed Limits

Vmo (Maximum Operating Speed)

CAS (K) IAS (K) Sea Level to 6700 Ft. 154 150 10,000 ft. 144 140 15,000 ft. 129 125 20,000 ft. 114 111 25,000 ft. 99 96

IAS (K) Viewport door (Maximum Activation Speed) 100

- END -

## Every issue (3)

- February 14, 2017: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/8d/62/8d62cbbd840f0da54253388889f70ac518d57009606c1bed1b0ea0b4082c7e9b)
- April 15, 2015: Reissued, Historical. [certificate](https://openairdocs.org/files/sha256/17/41/17412e80d55cca050e5d7581130a8b5d27890975eadb504d91a312f09a4de190)
- July 23, 1985: Issued, Historical. [certificate](https://openairdocs.org/files/sha256/48/6c/486cbf5d23b5bb95494b04f779d068bf261124ac1834f7e38a65ced70aa35f3d)

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