SA657WE
AiResearch GTP30-54 auxiliary turbine power unit for ground operation only. Held by Qualitron Aero INC, which holds 5 approved modifications in all. Last revised January 1, 1960. System: engine.
What it applies to
- Kind of product
- Aircraft
- Design holder
- Vickers-Armstrongs (Aircraft Limited); Vickers-Armstrongs (Aircraft Limited); Vickers-Armstrongs (Aircraft Limited)
- Models
- Viscount 744, Viscount 745D, Viscount 745
- Type certificates
- A-814, A-814, A-814
- 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 7, 2026.