SR02503SE
Installation of Additional Telemetry Unit (ATU). Held by Helicopter Transport Services LLC, which holds 27 approved modifications in all. Last revised September 15, 2016. System: other and general.
What it applies to
- Kind of product
- Aircraft
- Design holder
- Erickson Incorporated DBA Erickson Air-Crane; Helicopter Transport Services LLC; Helicopter Transport Services LLC; Helicopter Transport Services LLC
- Models
- S-64E, CH-54A, CH-54A, CH-54B
- Type certificates
- H6EA, H16NM, R00009SE, H14NM
- On this site
- Erickson S-64 5 registered
Helicopter Transport Services CH-54 5 registered - The FAA's record
- On the FAA's site
What an approved modification is
A supplemental type certificate is the FAA's approval of a change to a certified design: a new engine or propeller, avionics, an autopilot, floats, a parachute, a larger fuel tank, an ice-protection kit. The company holding it may sell the kit and the paperwork to owners of the listed models; the modification then becomes part of that aircraft's record. The FAA's list says what was approved and for which models, not how many aircraft carry it.
Source: FAA supplemental type certificates (Dynamic Regulatory System). Register counts from the FAA register of October 7, 2026.