SE00128WI
Add approved fuel: Unleaded automotive gasoline, 87 minimum antiknock index and leaded automotive gasoline, 88 minimum antiknock index(RON+MON0/2, per ASTM Spec D-439. Held by Petersen Aviation INC, which holds 167 approved modifications in all. Last revised January 27, 1994. System: engine.
What it applies to
- Kind of product
- Engine
- Design holder
- Franklin Engine Company
- Models
- 4AC-176 Series (Military 0-175-1)
- Type certificate
- E-221
- 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.