STC ST00355DE

United States of America Department of Transportation Federal Aviation Administration Supplemental Type Certificate Number: ST00355DE This certificate issued to: West Star Aviation Part 25 of the Federal Aviation Regulations.

Make: Raytheon Aircraft Company Model: HS. 125 Series 400A Description of Type Design Change:

Installation of TCAS II System and Mode S Transponders in accordance with West Star Aviation Master Data revision. List 1733-000, Rev. B, dated October 5, 1998, FAA approved dated October 9, 1998 or later FAA approved Limitations and Conditions:

1. This approval should not be extended to rotorcraft of this model on which other previously approved modifications are incorporated unless it is determined that the interrelationship between this change and any of those other previously approved modifications, including changes in type design, will introduce no adverse effect upon the airworthiness of that rotorcraft.

2. A copy of this Certificate and FAA Approved Aircraft Flight Manual Supplement, DOC. NO. 1733-100, dated 10/9/98 or later FAA approved revision must be maintained as part of the permanent records for the modified aircraft.

3. 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: September 1, 1998 Date Reissued:

Date of Issuance: October 9, 1998 Date Amended:

FEDERAL AVIATION Ronald F. May (Signature) Manager TOMINIST RATION Northwest Mountain Region Denver Aircraft Certification Office (Title)