# STC SR11923SE

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: Helicopter Transport Services LLC, United States
- Description: Installation of Helicopter Transport Services, LLC Shock Absorber HTS-2000
- Applied: April 28, 2024
- Status date: March 11, 2025
- Product: Aircraft, Rotorcraft
- Certification basis: Part 29
- Data sheets: [TCDS H6EA](https://openairdocs.org/tcds/H6EA), [TCDS H18NM](https://openairdocs.org/tcds/H18NM), [TCDS H14NM](https://openairdocs.org/tcds/H14NM), [TCDS H16NM](https://openairdocs.org/tcds/H16NM)
- Certificate PDF: https://openairdocs.org/files/sha256/83/c7/83c7306ae9abe16ab6e7e8a29e92828952ea8b695140f1adb7502e0ab7972150
- Approved model list and other attachments: [SR11923SE _AML.pdf](https://openairdocs.org/files/sha256/db/db/dbdb741e1b8b9e8c0ed21d5d0b0f502019ad7bcd3f7ec421e374abbc14da42dd)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/DRSDOCID159804534420250327161159.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SR11923SE

## ADs that name it (0)

None.

## Approved models (5)

- Erickson Air-Crane S-64E ([TCDS H6EA](https://openairdocs.org/tcds/H6EA))
- Erickson Air-Crane S-64F ([TCDS H6EA](https://openairdocs.org/tcds/H6EA))
- Helicopter Transport Services LLC CH-54A ([TCDS H16NM](https://openairdocs.org/tcds/H16NM))
- Helicopter Transport Services LLC CH-54B ([TCDS H14NM](https://openairdocs.org/tcds/H14NM))
- Siller Helicopters LLC CH-54A ([TCDS H18NM](https://openairdocs.org/tcds/H18NM))

## 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.

SR11923SE Helicopter Transport Services, LLC 14497 Keil Rd NE Aurora, OR 97002 Part 29 Title 14 CFR See AML SR11923SE See AML SR11923SE See AML SR11923SE Approval of this change in type design applies to the rotorcraft listed on AML SR11923SE only.

The installation should not be incorporated on any aircraft unless it is determined that the interrelationship between this installation and any previously approved configuration of the aircraft will not introduce any adverse effect the airworthiness of the aircraft.(Cont. on page 3.)

04/28/2024 03/11/2025 for Manager, West Certification Branch 3 Installation of Helicopter Transport Services, LLC Shock Absorber HTS-2000 in accordance with the Master Drawing List (MDL) MDL-HTS-SHOCK, Revision F, dated October 11, 2024, as listed on the AML, or a later approved revision. (Continued on Page 3)

SR11923SE 3

SR11923SE Description of Design Change (continued from Page 1):

1. Maintained in accordance with the Instructions for Continued Airworthiness (ICA) , document ICA-HTS-SHOCK, Revision C, dated September 26, 2024 or later accepted revision.

Limitations and Conditions (continued from Page 1):

1. A copy of this certificate, the AML SR11923SE, and the ICA, must be maintained as part of the permanent records for the modified aircraft.

2. Operational approval for external load operations must be granted by the local Aviation Authority.

3. If the holder permits another person to use this certificate to alter the product, the holder shall give the other person written evidence of that permission.

-------------------------------------------------End--------------------------------------------------------------

### SR11923SE _AML.pdf

Page 1 of 1 FEDERAL AVIATION ADMINISTRATION (FAA) APPROVED MODEL LIST (AML) SR11923SE FOR Helicopter Transport Services, LLC Shock Absorber HTS-2000 ISSUE DATE: March 11, 2025

**ITEM AIRCRAFT /**

**ROTORCRAFT MAKE**

**AIRCRAFT /**

**ROTORCRAFT MODEL**

**ORIGINAL TC NUMBER**

**CERTIFICATION**

**BASIS FOR**

**ALTERATION**

FAA APPROVED MASTER DOCUMENT LIST AML AMEND DATE Drawing Revision*

1. Erickson Air-Crane S-64E H6EA 14 CFR 29 MDL-HTS-SHOCK REVISION F

2. Erickson Air-Crane S-64F H6EA 14 CFR 29 MDL-HTS-SHOCK REVISION F

3. Siller Helicopters, Inc.

**CH-54A H18NM 14 CFR 29 MDL-HTS-SHOCK REVISION F**

4. Helicopter Transport Services CH-54A H16NM 14 CFR 29 MDL-HTS-SHOCK REVISION F

5. Helicopter Transport Services CH-54B H14NM 14 CFR 29 MDL-HTS-SHOCK REVISION F

6.

7.

8.

* Or later FAA Approved Revision for Manager, West Certification Branch REISSUED:

## Every issue (1)

- March 11, 2025: Issued, Current. [certificate](https://openairdocs.org/files/sha256/83/c7/83c7306ae9abe16ab6e7e8a29e92828952ea8b695140f1adb7502e0ab7972150), [SR11923SE _AML.pdf](https://openairdocs.org/files/sha256/db/db/dbdb741e1b8b9e8c0ed21d5d0b0f502019ad7bcd3f7ec421e374abbc14da42dd)

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