Definition
A specific provision in Title 14 of the Code of Federal Regulations, Part 23 (Airworthiness Standards for Normal Category Airplanes), which addresses flight, navigation, and powerplant instrument requirements. Subsection (b)(2) deals with the marking and identification of instruments, including required color-coded range markings on airspeed indicators and other flight instruments to indicate operating limitations.
Plain English
A rule in the FAA's airworthiness standards that requires certain flight instruments — like the airspeed indicator — to be marked with colored arcs and lines so the pilot can see at a glance which speeds are safe and which are limits.
Context Anchor
Seen in the Airplane Flying Handbook discussion of pitot-static system malfunctions, especially pitot heat and unreliable airspeed indications.
Derivation
The number is a regulatory citation. '23' is the Part of Title 14 CFR covering small airplane airworthiness; '2615' is the section number; '(b)(2)' identifies the specific paragraph within that section. Reading regulatory citations this way — Part, section, paragraph — works the same throughout the FAA's rules.
Why Pilots Care
Knowing this section helps pilots understand why certain backup instruments and alternate static ports exist and what level of accuracy the aircraft is certified to deliver during system failures.
Analogy
Think of section 23.2615(b)(2) like an address in a large rulebook. Part 23 is the neighborhood, 2615 is the building, and (b)(2) is the specific room where this requirement lives.
Intuition Check
Do not read section 23.2615(b)(2) as an airplane part or checklist step. It is a regulatory citation that points to a specific FAA certification requirement.
Example Sentence 1
The colored arcs on the airspeed indicator — white, green, yellow, and the red radial line — are required by section 23.2615(b)(2).
Example Sentence 2
During the malfunction discussion the handbook referred to section 23.2615(b)(2) to explain why the airspeed indicator behaved a certain way after the pitot tube iced over.