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227 

Federal Aviation Administration, DOT 

§ 25.207 

held full aft for a short time before re-
covery 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] 

§ 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 pos-
sible to promptly prevent stalling and 
to recover from a stall by normal use 
of the controls. 

(b) For level wing stalls, the roll oc-

curring between the stall and the com-
pletion of the recovery may not exceed 
approximately 20 degrees. 

(c) For turning flight stalls, the ac-

tion 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 dur-
ing the recovery may not exceed— 

(1) Approximately 60 degrees in the 

original direction of the turn, or 30 de-
grees in the opposite direction, for de-
celeration rates up to 1 knot per sec-
ond; and 

(2) Approximately 90 degrees in the 

original direction of the turn, or 60 de-
grees in the opposite direction, for de-
celeration rates in excess of 1 knot per 
second. 

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

§ 25.207

Stall warning. 

(a) Stall warning with sufficient mar-

gin to prevent inadvertent stalling 
with the flaps and landing gear in any 
normal position must be clear and dis-
tinctive to the pilot in straight and 
turning flight. 

(b) The warning must be furnished ei-

ther 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 warn-
ing device that requires the attention 
of the crew within the cockpit is not 

acceptable by itself. If a warning de-
vice is used, it must provide a warning 
in each of the airplane configurations 
prescribed in paragraph (a) of this sec-
tion at the speed prescribed in para-
graphs (c) and (d) of this section. Ex-
cept for the stall warning prescribed in 
paragraph (h)(3)(ii) of this section, the 
stall warning for flight in icing condi-
tions 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 nor-
mal configuration, at a speed, V

SW

, ex-

ceeding the speed at which the stall is 
identified in accordance with § 25.201(d) 
by not less than five knots or five per-
cent 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 center- 
of-gravity position specified in 
§ 25.103(b)(5), V

SW

, in each normal con-

figuration, must exceed V

SR

by not less 

than three knots or three percent CAS, 
whichever is greater. 

(e) In icing conditions, the stall 

warning margin in straight and turn-
ing flight must be sufficient to allow 
the pilot to prevent stalling (as defined 
in § 25.201(d)) when the pilot starts a re-
covery maneuver not less than three 
seconds after the onset of stall warn-
ing. When demonstrating compliance 
with this paragraph, the pilot must 
perform the recovery maneuver in the 
same way as for the airplane in non- 
icing 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 de-
fined in Appendices C and O of this 
part, as applicable, in accordance with 
§ 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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