SA4557NM
Installation of Retardant Tanks for the special purpose of Forest and Wildlife Conservation. (Approved for SN 56-0530 only). Held by Heavy Lift Helicopters INC, which holds 3 approved modifications in all. Last revised August 21, 2002. System: other and general.
What it applies to
- Kind of product
- Aircraft
- Design holder
- USDA Forest Service
- Models
- C-130A
- Type certificate
- A15NM
- On this site
- Lockheed C-130 Hercules 18 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 8, 2026.