FAR 23.2200 — Structural Design Envelope
FAR 23.2200 defines the structural design envelope for Part 23 airplanes — design airspeeds, load factors, weights, controls, and altitudes.
In Plain English
FAR 23.2200 requires the applicant (the airplane manufacturer seeking certification under Part 23) to define a structural design envelope — the boundaries of design and operating conditions the airplane must be shown to handle safely. This envelope drives every structural compliance test under Subpart C.
The applicant must account for every parameter that affects loads, strength, durability, and aeroelasticity, including:
- Structural design airspeeds (and landing descent speeds) that are well above stall speed to protect against loss of control in turbulence, with margin for setting practical operating limits.
- Design maneuvering load factors at least as high as service history shows can occur within the envelope.
- Inertial properties — weight, CG, and mass moments of inertia — covering empty weight up to max weight, including occupants, payload, and fuel distribution.
- Control system characteristics, such as range of motion and tolerances of control surfaces, flaps, and other moveable surfaces.
- Each critical altitude up to the maximum certified altitude.
For pilots, this is the regulation behind the V-speeds, weight-and-balance limits, and altitude limits printed in your POH — the airplane is only proven safe inside that envelope.
Regulation Text
14 CFR § 23.2200§ 23.2200 Structural design envelope.
The applicant must determine the structural design envelope, which describes the range and limits of airplane design and operational parameters for which the applicant will show compliance with the requirements of this subpart. The applicant must account for all airplane design and operational parameters that affect structural loads, strength, durability, and aeroelasticity, including:
(a) Structural design airspeeds, landing descent speeds, and any other airspeed limitation at which the applicant must show compliance to the requirements of this subpart. The structural design airspeeds must—
(1) Be sufficiently greater than the stalling speed of the airplane to safeguard against loss of control in turbulent air; and
(2) Provide sufficient margin for the establishment of practical operational limiting airspeeds.
(b) Design maneuvering load factors not less than those, which service history shows, may occur within the structural design envelope.
(c) Inertial properties including weight, center of gravity, and mass moments of inertia, accounting for—
(1) Each critical weight from the airplane empty weight to the maximum weight; and
(2) The weight and distribution of occupants, payload, and fuel.
(d) Characteristics of airplane control systems, including range of motion and tolerances for control surfaces, high-lift devices, or other moveable surfaces.
(e) Each critical altitude up to the maximum altitude.
[Doc. No. FAA-2015-1621, Amdt. 23-64, 81 FR 96689, Dec. 30, 2016, as amended by Doc. No. FAA-2022-1355, Amdt. 23-65, 87 FR 75710, Dec. 9, 2022]
Oral Exam Questions a DPE Might Ask
Q1What is the structural design envelope, and who is responsible for establishing it?
Per FAR 23.2200, the structural design envelope is the range and limits of design and operational parameters for which the applicant (manufacturer) must show structural compliance under Subpart C of Part 23.
Q2What requirements does FAR 23.2200 place on structural design airspeeds?
FAR 23.2200(a) requires structural design airspeeds to be sufficiently greater than stall speed to safeguard against loss of control in turbulent air, and to provide enough margin to establish practical operating limit airspeeds.
Q3What inertial properties must the applicant consider when defining the structural design envelope?
Under FAR 23.2200(c), the applicant must account for weight, center of gravity, and mass moments of inertia across every critical weight from empty to maximum, including the weight and distribution of occupants, payload, and fuel.
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Related Sections in Part 23