STC SA3887WE

United States of America Department of Transportation Federal Aviation Administration Supplemental Type Certificate Number: SA388TWE This certificate issued to: Northwest Airlines, Inc.

2700 Lone Oak Parkway Eagan, MN 55124 Part 4b if the CiVil Air Regulations. (Certification basis is stated in T.C. Data Sheet AGWE) Original Product - Type Bertificate, Lumber: AGWE Make: McDonnell Douglas

• Mired: DC- 9-30 Description of Type Design Change:

Installation of two Howell Model H900 Solid State Exhaust Gas Temperature Indicators in accordance with the FAA sealed Hughes Airwest Master Drawing List No. RW7720009, Revision B, dated November 27, 1978, or later FAA approved revision.

This approval should not be extended to other aircraft of these models on which other previously approved modifications are incorporated unless it is determined by the installer that the interrelationship between this change and any of those other previously approved modifications will introduce no adverse effect upon the

Date of Application: March 22, 1978 Date Reissued: October 13, 1982 November 14, 1986 March 29, 1979 I atrumended:

FEDERAL AVIATION By directife t the tuninis truler W. F. Aorn (Signature) TAMINISTRAIOS Manager, Chicago Aircraft Certification Office, ACE-115C, Central Region, FAA (Title)

47.