What it approves
Conversion of the Pratt & Whitney PT6T-3 to the PT6T-3B configuration
What the certificate says
From the PDF’s text layer, without the form’s printed wording. Layout and order may differ; the PDF is the record.
United States of America Department of Transportation Federal AviationAdministration Supplemental Type Certificate Number: SR04549AT 3
This certificate issued to: Centerpointe Aerospace 279 Blackland Road Fate, Texas 75189 Part 29 of Federal Aviation Regulations .
1H11 Make: Sikorsky Model: S-58BT, S-58DT, S58-ET, S-58FT, S-58HT, Description of Type Design Change: S-58JT Conversion of the Pratt & Whitney PT6T-3 to the PT6T-3B configuration per Pratt & Whitney Canada Service Bulletin No. PT6T-72-5252, Rev. No. 3, dated Feb16, 2018 (P&WC S.B. No. 5252R3).
The installer must determine whether this design change is compatible with previously approved modifications. If the holder agrees to permit another person to use this certificate to alter a product, the holder must give the other person written evidence of that permission. Airworthiness limitations of the replacement power sections remains unchanged. (See continuation sheet 3)
Date of Application: August 23, 2022
Date Reissued: February 21, 2023
Date of Issuance: October 4, 2022 Date Amended:
(For) Christina M. Underwood, Manager, Atlanta ACO Branch
United States of America Department of Transportation Federal AviationAdministration Supplemental Type Certificate Number: SR04549AT 3
Date o transfer:
United States of America Department of Transportation Federal AviationAdministration Supplemental Type Certificate
(Continuation Sheet) Number: SR04549AT Limitations and Conditions (Cont.)
The PT6T-3B power section installed as the replacement for a PT6T-3 power section must be operated as a PT6T-3 and maintained as a PT6T-3B power section.
Replacement power sections must be operated under the lower performance/power levels of the original power sections in accordance with existing applicable Aircraft Flight Manual (AFM).
Weight and Balance Since P&W has provided the below information for all W&B changes, no additional analysis will be required. The effective CG change is minimal.
The following engine weight corrections should be made, and W&B calculations determined and logged into the AFM PT6T-3B Assembly +12.0 lbs PT6T-3B Power Section L.H. +6.0 lbs PT6T-3B Power Section R.H. +6.0 lbs
Certification Basis The certification basis is Title 14 CFR Part 29 effective February 1, 1965, including Amendments 29-1 through 29-3 and as described in TCDS 1H11, Rev. No. 19 for APECS Aerospace S-58 Series helicopters. Refer to Note 10 specifically for the introduction of the P&WC PT6T-3 Engines.
ADs that name this STC · 0
An AD can apply because an STC is installed, or mention one in its text.
Approved models · 6
Every issue · 2
DRS keeps each issue of an STC as its own record, with its own certificate and attachments.
| Date | Status | Files |
|---|---|---|
| February 21, 2023 | Reissued, current | Certificate |
| November 17, 2022 | Issued, earlier issue | Certificate |