393 

Federal Aviation Administration, DOT 

§ 25.207 

(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 showing compliance with the 
stall warning margin prescribed in 
paragraph (h)(3)(ii) of this section, stall 
warning for flight in icing conditions 
must be provided by the same means as 
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 more critical of the takeoff 

ice and final takeoff ice accretions de-
fined in appendix C for each configura-
tion used in the takeoff phase of flight; 

(2) The en route ice accretion defined 

in appendix C for the en route configu-
ration; 

(3) The holding ice accretion defined 

in appendix C for the holding configu-
ration(s); 

(4) The approach ice accretion de-

fined in appendix C for the approach 
configuration(s); and 

(5) The landing ice accretion defined 

in appendix C for the landing and go- 
around configuration(s). 

(f) The stall warning margin must be 

sufficient in both non-icing and icing 
conditions to allow the pilot to prevent 
stalling when the pilot starts a recov-
ery maneuver not less than one second 
after the onset of stall warning in slow- 
down turns with at least 1.5 g load fac-
tor normal to the flight path and air-
speed deceleration rates of at least 2 
knots per second. When demonstrating 

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