SA236CH
Installation of Allied Signal, Inc., (Garrett) TPE331-10T series engines (-512K, -515K, or -516K in the 690A and 690B; -511K or -513K in the 690C and 690D) and related changes. Held by Twin Commander Aircraft LLC, which holds 6 approved modifications in all. Last revised July 24, 2014. System: engine.
What it applies to
- Kind of product
- Aircraft
- Design holder
- Twin Commander Aircraft LLC; Twin Commander Aircraft LLC; Twin Commander Aircraft LLC; Twin Commander Aircraft LLC
- Models
- 690A, 690B, 690C, 690D
- Type certificates
- 2A4, 2A4, 2A4, 2A4
- 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 5, 2026.