122
14 CFR Ch. I (1–1–19 Edition)
§ 121.329
and
flight altitude
means the altitude
above sea level at which the airplane is
operated. For airplanes without pres-
surized cabins, ‘‘cabin pressure alti-
tude’’ and ‘‘flight altitude’’ mean the
same thing.
§ 121.329
Supplemental oxygen for sus-
tenance: Turbine engine powered
airplanes.
(a)
General.
When operating a turbine
engine powered airplane, each certifi-
cate holder shall equip the airplane
with sustaining oxygen and dispensing
equipment for use as set forth in this
section:
(1) The amount of oxygen provided
must be at least the quantity nec-
essary to comply with paragraphs (b)
and (c) of this section.
(2) The amount of sustaining and
first-aid oxygen required for a par-
ticular operation to comply with the
rules in this part is determined on the
basis of cabin pressure altitudes and
flight duration, consistent with the op-
erating procedures established for each
operation and route.
(3) The requirements for airplanes
with pressurized cabins are determined
on the basis of cabin pressure altitude
and the assumption that a cabin pres-
surization failure will occur at the alti-
tude or point of flight that is most
critical from the standpoint of oxygen
need, and that after the failure the air-
plane will descend in accordance with
the emergency procedures specified in
the Airplane Flight Manual, without
exceeding its operating limitations, to
a flight altitude that will allow suc-
cessful termination of the flight.
(4) Following the failure, the cabin
pressure altitude is considered to be
the same as the flight altitude unless it
is shown that no probable failure of the
cabin or pressurization equipment will
result in a cabin pressure altitude
equal to the flight altitude. Under
those circumstances, the maximum
cabin pressure altitude attained may
be used as a basis for certification or
determination of oxygen supply, or
both.
(b)
Crewmembers.
Each certificate
holder shall provide a supply of oxygen
for crewmembers in accordance with
the following:
(1) At cabin pressure altitudes above
10,000 feet, up to and including 12,000
feet, oxygen must be provided for and
used by each member of the flight crew
on flight deck duty and must be pro-
vided for other crewmembers for that
part of the flight at those altitudes
that is of more than 30 minutes dura-
tion.
(2) At cabin pressure altitudes above
12,000 feet, oxygen must be provided
for, and used by, each member of the
flight crew on flight deck duty, and
must be provided for other crew-
members during the entire flight at
those altitudes.
(3) When a flight crewmember is re-
quired to use oxygen, he must use it
continuously except when necessary to
remove the oxygen mask or other dis-
penser in connection with his regular
duties. Standby crewmembers who are
on call or are definitely going to have
flight deck duty before completing the
flight must be provided with an
amount of supplemental oxygen equal
to that provided for crewmembers on
duty other than on flight duty. If a
standby crewmember is not on call and
will not be on flight deck duty during
the remainder of the flight, he is con-
sidered to be a passenger for the pur-
poses of supplemental oxygen require-
ments.
(c)
Passengers.
Each certificate holder
shall provide a supply of oxygen for
passengers in accordance with the fol-
lowing:
(1) For flights at cabin pressure alti-
tudes above 10,000 feet, up to and in-
cluding 14,000 feet, enough oxygen for
that part of the flight at those alti-
tudes that is of more than 30 minutes
duration, for 10 percent of the pas-
sengers.
(2) For flights at cabin pressure alti-
tudes above 14,000 feet, up to and in-
cluding 15,000 feet, enough oxygen for
that part of the flight at those alti-
tudes for 30 percent of the passengers.
(3) For flights at cabin pressure alti-
tudes above 15,000 feet, enough oxygen
for each passenger carried during the
entire flight at those altitudes.
VerDate Sep<11>2014
08:20 May 17, 2019
Jkt 247048
PO 00000
Frm 00132
Fmt 8010
Sfmt 8010
Y:\SGML\247048.XXX
247048