SA6NE
Installation of Whelen anti- collision strobe light power supplies, Models HS-41 and HD-42 as direct replacements for Models HS and HD installed in accordance with STC SA615EA or STC SA800EA. (172M S/N 17263459 - 17267584). Held by Whelen Engineering CO INC, which holds 9 approved modifications in all. Last revised March 21, 1974. System: electrical power.
What it applies to
- Kind of product
- Aircraft
- Design holder
- The Cessna Aircraft Company
- Models
- 172M
- Type certificate
- 3A12
- On this site
- Cessna 172 Skyhawk 20,669 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 5, 2026.