Pt. 25, App. F

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

the specimen must be the same as that of the
aircraft component it represents up to a
maximum thickness of 1.75 inches (45 mm).
Test specimens representing thicker components must be 1.75 inches (45 mm).
(2) Conditioning. Specimens must be conditioned as described in Part 1 of this appendix.
(3) Mounting. Each test specimen must be
wrapped tightly on all sides of the specimen,
except for the one surface that is exposed
with a single layer of .001 inch (.025 mm) aluminum foil.
(e) Procedure. (1) The power supply to the
radiant panel must be set to produce a radiant flux of 3.5 Section.05 W/cm2, as measured at the
point the center of the specimen surface will
occupy when positioned for the test. The radiant flux must be measured after the air
flow through the equipment is adjusted to
the desired rate.
(2) After the pilot flames are lighted, their
position must be checked as described in
paragraph (b)(8) of this part IV.
(3) Air flow through the apparatus must be
controlled by a circular plate orifice located
in a 1.5 inch (38.1 mm) I.D. pipe with two
pressure measuring points, located 1.5 inches
(38 mm) upstream and .75 inches (19 mm)
downstream of the orifice plate. The pipe
must be connected to a manometer set at a
pressure differential of 7.87 inches (200 mm)
of Hg. (See Figure 1B of this part IV.) The
total air flow to the equipment is approximately .04 m3/seconds. The stop on the
vertical specimen holder rod must be adjusted so that the exposed surface of the
specimen is positioned 3.9 inches (100 mm)
from the entrance when injected into the environmental chamber.

(F1  -  FO )  (210.8  -  22)k cal  273  P  -  Pv  mole CH 4STP  WATT min  kw
mole
Ta
760
22.41
.01433kcal 1000w
(V1  -  VO )

(2) Heat release rates may be calculated
from the reading of the thermopile output
voltage at any instant of time as:

spaschal on DSK3GDR082PROD with CFR

HRR =

(Vm  -  Vb )K n
.02323m

2

HRR = heat release rate (kw/m2)
Vb = baseline voltage (mv)
Vm = measured thermopile voltage (mv)

Kh = calibration factor (kw/mv)
(3) The integral of the heat release rate is
the total heat release as a function of time
and is calculated by multiplying the rate by
the data sampling frequency in minutes and
summing the time from zero to two minutes.
(g) Criteria. The total positive heat release
over the first two minutes of exposure for
each of the three or more samples tested
must be averaged, and the peak heat release
rate for each of the samples must be averaged. The average total heat release must
not exceed 65 kilowatt-minutes per square
meter, and the average peak heat release
rate must not exceed 65 kilowatts per square
meter.

410

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ER02FE95.006</MATH>

F0 = flow of methane at baseline (1pm)
F1 = higher preset flow of methane (1pm)
V0 = thermopile voltage at baseline (mv)
V1 = thermopile voltage at higher flow (mv)
Ta = Ambient temperature (K)
P = Ambient pressure (mm Hg)
Pv = Water vapor pressure (mm Hg)

EC28SE91.072</MATH>

Kh =

(4) The specimen must be placed in the
hold chamber with the radiation doors
closed. The airtight outer door must be secured, and the recording devices must be
started. The specimen must be retained in
the hold chamber for 60 seconds, plus or
minus 10 seconds, before injection. The thermopile  - zero -  value must be determined during the last 20 seconds of the hold period.
The sample must not be injected before completion of the  - zero -  value determination.
(5) When the specimen is to be injected, the
radiation doors must be opened. After the
specimen is injected into the environmental
chamber, the radiation doors must be closed
behind the specimen.
(6) [Reserved]
(7) Injection of the specimen and closure of
the inner door marks time zero. A record of
the thermopile output with at least one data
point per second must be made during the
time the specimen is in the environmental
chamber.
(8) The test duration is five minutes. The
lower pilot burner and the upper pilot burner
must remain lighted for the entire duration
of the test, except that there may be intermittent flame extinguishment for periods
that do not exceed 3 seconds. Furthermore, if
the optional three-hole upper burner is used,
at least two flamelets must remain lighted
for the entire duration of the test, except
that there may be intermittent flame extinguishment of all three flamelets for periods
that do not exceed 3 seconds.
(9) A minimum of three specimens must be
tested.
(f) Calculations. (1) The calibration factor is
calculated as follows: