Definition
A specific paragraph within the Federal Aviation Regulations addressing civil airport takeoff minimums. Paragraph (f)(4) of 14 CFR 91.175 permits a pilot conducting a takeoff under Part 91 to use weather minimums lower than those published as standard takeoff minimums (or any other minimums prescribed for the airport), provided the pilot complies with any contingency procedures, climb gradients, or departure procedures specified for that operation. In practical terms, this is the regulatory basis that allows Part 91 operators flexibility on takeoff minimums that more restrictive operators (Part 121, 135) do not have.
Plain English
A rule that lets pilots flying under the basic general aviation rules (Part 91) take off in weather worse than the published takeoff minimums, as long as they follow any related departure procedures. Other types of operators -- like the airlines or charter pilots -- are held to stricter rules.
Context Anchor
Seen in instrument departure planning, especially when comparing published obstacle departure procedures with one-engine-inoperative takeoff obstacle clearance planning.
Derivation
The citation format breaks down as: '14' is the title of the Code of Federal Regulations covering aeronautics and space, 'CFR' stands for Code of Federal Regulations (the official rulebook of U.S. federal agencies), '91' is the part covering general operating and flight rules, '175' is the section on takeoff and landing under IFR, '(f)' is the subsection on civil airport takeoff minimums, and '(4)' is the specific paragraph within that subsection. Knowing how to read the citation makes it easy to look up any FAR quickly.
Why Pilots Care
Meeting this requirement guarantees the airplane can still clear obstacles and reach a safe altitude even after an engine failure on takeoff.
Intuition Check
Do not read 14 CFR 91.175(f)(4) as the name of a departure procedure. It is a regulation citation that points to a legal requirement; the actual departure path and the aircraft’s climb ability are separate issues.
Example Sentence 1
Under 14 CFR 91.175(f)(4), the pilot was legally permitted to depart with visibility below standard takeoff minimums, but he chose to wait for conditions to improve.
Example Sentence 2
Dispatch confirmed the aircraft performance data satisfied 14 CFR 91.175(f)(4) for the planned one-engine-inoperative departure path.