ST553CH
Installation of Envirovac toilets P/N's7900061-1, 7900062-1, 7900063-1, 7900064-1. Held by Monogram Systems, which holds 33 approved modifications in all. Last revised May 26, 2009. System: other and general.
What it applies to
- Kind of product
- Aircraft
- Design holder
- The Boeing Company; The Boeing Company; The Boeing Company; The Boeing Company
- Models
- 767-200 Series, 767-300 Series, 747-400 Series, 777-200 Series
- Type certificates
- A1NM, A1NM, A20WE, T00001SE
- On this site
- Boeing 747 192 registered
Boeing 767 584 registered
Boeing 777 358 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 20, 2026.