title-14-part-29-sec29-1049

644

14 CFR Ch. I (1–1–24 Edition)

§ 29.1047

rotorcraft reaches the maximum alti-
tude for which certification is re-
quested.

(e) For category B rotorcraft without

a positive rate of climb, the descent
must begin at the all-engine-critical
altitude and end at the higher of—

(1) The maximum altitude at which

level flight can be maintained with one
engine operative; and

(2) Sea level.
(f) The climb or descent must be con-

ducted at an airspeed representing a
normal operational practice for the
configuration being tested. However, if
the cooling provisions are sensitive to
rotorcraft speed, the most critical air-
speed must be used, but need not ex-
ceed the speeds established under
§ 29.67(a)(2) or § 29.67(b). The climb cool-
ing test may be conducted in conjunc-
tion with the takeoff cooling test of
§ 29.1047.

[Doc. No. 5084, 29 FR 16150, Dec. 3, 1964, as
amended by Amdt. 29–26, 53 FR 34218, Sept. 2,
1988]

§ 29.1047

Takeoff cooling test proce-

dures.

(a)

Category A. For each category A

rotorcraft, cooling must be shown dur-
ing takeoff and subsequent climb as
follows:

(1) Each temperature must be sta-

bilized while hovering in ground effect
with—

(i) The power necessary for hovering;
(ii) The appropriate cowl flap and

shutter settings; and

(iii) The maximum weight.
(2) After the temperatures have sta-

bilized, a climb must be started at the
lowest practicable altitude and must be
conducted with one engine inoperative.

(3) The operating engines must be at

the greatest power for which approval
is sought (or at full throttle when
above the critical altitude) for the
same period as this power is used in de-
termining the takeoff climbout path
under § 29.59.

(4) At the end of the time interval

prescribed in paragraph (b)(3) of this
section, the power must be changed to
that used in meeting § 29.67(a)(2) and
the climb must be continued for—

(i) Thirty minutes, if 30-minute OEI

power is used; or

(ii) At least 5 minutes after the oc-

currence of the highest temperature re-
corded, if continuous OEI power or
maximum continuous power is used.

(5) The speeds must be those used in

determining the takeoff flight path
under § 29.59.

(b)

Category B. For each category B

rotorcraft, cooling must be shown dur-
ing takeoff and subsequent climb as
follows:

(1) Each temperature must be sta-

bilized while hovering in ground effect
with—

(i) The power necessary for hovering;
(ii) The appropriate cowl flap and

shutter settings; and

(iii) The maximum weight.
(2) After the temperatures have sta-

bilized, a climb must be started at the
lowest practicable altitude with take-
off power.

(3) Takeoff power must be used for

the same time interval as takeoff
power is used in determining the take-
off flight path under § 29.63.

(4) At the end of the time interval

prescribed in paragraph (a)(3) of this
section, the power must be reduced to
maximum continuous power and the
climb must be continued for at least
five minutes after the occurance of the
highest temperature recorded.

(5) The cooling test must be con-

ducted at an airspeed corresponding to
normal operating practice for the con-
figuration being tested. However, if the
cooling provisions are sensitive to
rotorcraft speed, the most critical air-
speed must be used, but need not ex-
ceed the speed for best rate of climb
with maximum continuous power.

[Doc. No. 5084, 29 FR 16150, Dec. 3, 1964, as
amended by Amdt. 29–1, 30 FR 8778, July 13,
1965; Amdt. 29–26, 53 FR 34219, Sept. 2, 1988]

§ 29.1049

Hovering cooling test proce-

dures.

The hovering cooling provisions must

be shown—

(a) At maximum weight or at the

greatest weight at which the rotorcraft
can hover (if less), at sea level, with
the power required to hover but not
more than maximum continuous
power, in the ground effect in still air,
until at least five minutes after the oc-
currence of the highest temperature re-
corded; and

VerDate Sep<11>2014

09:06 Jun 28, 2024

Jkt 262046

PO 00000

Frm 00654

Fmt 8010

Sfmt 8010

Y:\SGML\262046.XXX

262046

jspears on DSK121TN23PROD with CFR

645

Federal Aviation Administration, DOT

§ 29.1093

(b) With maximum continuous power,

maximum weight, and at the altitude
resulting in zero rate of climb for this
configuration, until at least five min-
utes after the occurrence of the highest
temperature recorded.

NDUCTION

YSTEM

§ 29.1091

Air induction.

(a) The air induction system for each

engine and auxiliary power unit must
supply the air required by that engine
and auxiliary power unit under the op-
erating conditions for which certifi-
cation is requested.

(b) Each engine and auxiliary power

unit air induction system must provide
air for proper fuel metering and mix-
ture distribution with the induction
system valves in any position.

the engine accessory section or within
other areas of any powerplant compart-
ment where emergence of backfire
flame would constitute a fire hazard.

(d) Each reciprocating engine must

have an alternate air source.

(e) Each alternate air intake must be

located to prevent the entrance of rain,
ice, or other foreign matter.

(f) For turbine engine powered rotor-

craft and rotorcraft incorporating aux-
iliary power units—

(1) There must be means to prevent

hazardous quantities of fuel leakage or
overflow from drains, vents, or other
components of flammable fluid systems
from entering the engine or auxiliary
power unit intake system; and

(2) The air inlet ducts must be lo-

cated or protected so as to minimize
the ingestion of foreign matter during
takeoff, landing, and taxiing.

(Secs. 313(a), 601, 603, 604, Federal Aviation
Act of 1958 (49 U.S.C. 1354(a), 1421, 1423, 1424),
sec. 6(c), Dept. of Transportation Act (49
U.S.C. 1655(c)))

[Doc. No. 5084, 29 FR 16150, Dec. 3, 1964, as
amended by Amdt. 29–3, 33 FR 969, Jan. 26,
1968; Amdt. 29–17, 43 FR 50601, Oct. 30, 1978]

§ 29.1093

Induction system icing pro-

tection.

(a)

Reciprocating engines. Each recip-

rocating engine air induction system
must have means to prevent and elimi-
nate icing. Unless this is done by other
means, it must be shown that, in air

free of visible moisture at a tempera-
ture of 30

F., and with the engines at

60 percent of maximum continuous
power—

(1) Each rotorcraft with sea level en-

gines using conventional venturi car-
buretors has a preheater that can pro-
vide a heat rise of 90

F.;

(2) Each rotorcraft with sea level en-

gines using carburetors tending to pre-
vent icing has a preheater that can
provide a heat rise of 70

F.;

(3) Each rotorcraft with altitude en-

gines using conventional venturi car-
buretors has a preheater that can pro-
vide a heat rise of 120

F.; and

(4) Each rotorcraft with altitude en-

gines using carburetors tending to pre-
vent icing has a preheater that can
provide a heat rise of 100

(b)

Turbine engines. (1) It must be

shown that each turbine engine and its
air inlet system can operate through-
out the flight power range of the en-
gine (including idling)—

(i) Without accumulating ice on en-

gine or inlet system components that
would adversely affect engine oper-
ation or cause a serious loss of power
under the icing conditions specified in
appendix C of this Part; and

(ii) In snow, both falling and blowing,

without adverse effect on engine oper-
ation, within the limitations estab-
lished for the rotorcraft.

(2) Each turbine engine must idle for

30 minutes on the ground, with the air
bleed available for engine icing protec-
tion at its critical condition, without
adverse effect, in an atmosphere that is
at a temperature between 15

and 30

(between

and

C) and has a liq-

uid water content not less than 0.3
grams per cubic meter in the form of
drops having a mean effective diameter
not less than 20 microns, followed by
momentary operation at takeoff power
or thrust. During the 30 minutes of idle
operation, the engine may be run up
periodically to a moderate power or
thrust setting in a manner acceptable
to the Administrator.

(c)

Supercharged reciprocating engines.

For each engine having a supercharger
to pressurize the air before it enters
the carburetor, the heat rise in the air
caused by that supercharging at any
altitude may be utilized in determining
compliance with paragraph (a) of this