Section 25.203

14 CFR Ch. I (1-1-19 Edition)

held full aft for a short time before recovery is initiated.
[Doc. No. 5066, 29 FR 18291, Dec. 24, 1964, as
amended by Amdt. 25-84, 60 FR 30750, June 9,
1995; Amdt. 25-108, 67 FR 70827, Nov. 26, 2002]

Section 25.203 Stall characteristics.
(a) It must be possible to produce and
to correct roll and yaw by unreversed
use of the aileron and rudder controls,
up to the time the airplane is stalled.
No abnormal nose-up pitching may
occur. The longitudinal control force
must be positive up to and throughout
the stall. In addition, it must be possible to promptly prevent stalling and
to recover from a stall by normal use
of the controls.
(b) For level wing stalls, the roll occurring between the stall and the completion of the recovery may not exceed
approximately 20 degrees.
(c) For turning flight stalls, the action of the airplane after the stall may
not be so violent or extreme as to
make it difficult, with normal piloting
skill, to effect a prompt recovery and
to regain control of the airplane. The
maximum bank angle that occurs during the recovery may not exceed - 
(1) Approximately 60 degrees in the
original direction of the turn, or 30 degrees in the opposite direction, for deceleration rates up to 1 knot per second; and
(2) Approximately 90 degrees in the
original direction of the turn, or 60 degrees in the opposite direction, for deceleration rates in excess of 1 knot per
second.

spaschal on DSK3GDR082PROD with CFR

[Doc. No. 5066, 29 FR 18291, Dec. 24, 1964, as
amended by Amdt. 25-84, 60 FR 30750, June 9,
1995]

Section 25.207 Stall warning.
(a) Stall warning with sufficient margin to prevent inadvertent stalling
with the flaps and landing gear in any
normal position must be clear and distinctive to the pilot in straight and
turning flight.
(b) The warning must be furnished either through the inherent aerodynamic
qualities of the airplane or by a device
that will give clearly distinguishable
indications under expected conditions
of flight. However, a visual stall warning device that requires the attention
of the crew within the cockpit is not

acceptable by itself. If a warning device is used, it must provide a warning
in each of the airplane configurations
prescribed in paragraph (a) of this section at the speed prescribed in paragraphs (c) and (d) of this section. Except for the stall warning prescribed in
paragraph (h)(3)(ii) of this section, the
stall warning for flight in icing conditions must be provided by the same
means as the stall warning for flight in
non-icing conditions.
(c) When the speed is reduced at rates
not exceeding one knot per second,
stall warning must begin, in each normal configuration, at a speed, VSW, exceeding the speed at which the stall is
identified in accordance with Section 25.201(d)
by not less than five knots or five percent CAS, whichever is greater. Once
initiated, stall warning must continue
until the angle of attack is reduced to
approximately that at which stall
warning began.
(d) In addition to the requirement of
paragraph (c) of this section, when the
speed is reduced at rates not exceeding
one knot per second, in straight flight
with engines idling and at the centerof-gravity
position
specified
in
Section 25.103(b)(5), VSW, in each normal configuration, must exceed VSR by not less
than three knots or three percent CAS,
whichever is greater.
(e) In icing conditions, the stall
warning margin in straight and turning flight must be sufficient to allow
the pilot to prevent stalling (as defined
in Section 25.201(d)) when the pilot starts a recovery maneuver not less than three
seconds after the onset of stall warning. When demonstrating compliance
with this paragraph, the pilot must
perform the recovery maneuver in the
same way as for the airplane in nonicing conditions. Compliance with this
requirement must be demonstrated in
flight with the speed reduced at rates
not exceeding one knot per second,
with - 
(1) The most critical of the takeoff
ice and final takeoff ice accretions defined in Appendices C and O of this
part, as applicable, in accordance with
Section 25.21(g), for each configuration used in
the takeoff phase of flight;
(2) The most critical of the en route
ice accretion(s) defined in Appendices C

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