SA8596SW
Installation of left (right) hand forward inboard fuel tank bladder cells, P/N DF304-1 (2) as a replacement for original bladders, P/N 5630304-1 (-2). Held by Floats & Fuel Cells, which holds 17 approved modifications in all. Last revised July 31, 2002. System: fuel system.
What it applies to
- Kind of product
- Aircraft
- Design holder
- Twin Commander Aircraft Corporation; Twin Commander Aircraft Corporation; Twin Commander Aircraft Corporation; Twin Commander Aircraft Corporation
- Models
- 685, 690, 690A, 690B
- 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.