SA2258WE
The installation of Firestone 40 X 14-21 tires at 40% tire deflection per sealed Piedmont Service Evaluation Report SER Number 70-18, and Supplement "A" to Airplane Flight Manual Dt-8737, 201. Held by Piedmont Aviation INC, which holds 34 approved modifications in all. Last revised October 19, 1970. System: landing gear.
What it applies to
- Kind of product
- Aircraft
- Design holder
- The Boeing Company
- Models
- 737-200 Series
- Type certificate
- A16WE
- On this site
- Boeing 737 2,887 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 7, 2026.