SR09222RC
Installation of a modified fin spar. Held by Midwest Aerospace Tc LLC, which holds 11 approved modifications in all. Last revised February 2, 2009. System: airframe structure.
What it applies to
- Kind of product
- Aircraft
- Design holder
- Rotorcraft Development Corporation; Rotorcraft Development Corporation; Rotorcraft Development Corporation
- Models
- TH-1F, UH-1P, UH-1F
- Type certificates
- H12NM, H12NM, H12NM
- 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.