This presentation details the development of the FAA's laboratory test for aircraft seat cushions, including procedure, criteria, and methods of testing.
Development of Fire Test for Aircraft Seat Cushions
1. Consumer Product Safety Commission Meeting
Rockville, MD, April 25, 2013
Federal Aviation
Administration
Richard E. Lyon
Manager, FAA Fire Research
William J. Hughes Technical Center
Atlantic City International Airport, NJ
Development of a Fire
Test for Aircraft Seat
Cushions
2. 2Federal Aviation
Administration
Development of FAA Fire Test for Seat Cushions
CPSC Meeting, April 25, 2013
Development of a Fire Test for
Aircraft Seat Cushions
• Result of fatal post-crash fires.
• Work performed in early 1980s at new full scale test
facility at FAA Tech Center.
• Rule implemented 1984-1987 required retrofit of
650,000 aircraft seats with fire blocking layers.
• First fire regulation that went beyond a simple Bunsen
burner test (i.e., FR foam).
9. 9Federal Aviation
Administration
Development of FAA Fire Test for Seat Cushions
CPSC Meeting, April 25, 2013
For Small Ignition Source > Cigarette,
FR Foam Alone was Ineffective
No Blocker
FR Foam
Foam Fire Blocker Fabric Fire Blocker
Seat Cushion Construction
FR Foam PU Foam PU FoamFR Foam
For Fire Blocked Seats FR Foam was Unnecessary
11. 11Federal Aviation
Administration
Development of FAA Fire Test for Seat Cushions
CPSC Meeting, April 25, 2013
No Fire Blocker Fire Blocker
Effectiveness of Fire Blocking Layer
at 2 minutes into test
12. 12Federal Aviation
Administration
Development of FAA Fire Test for Seat Cushions
CPSC Meeting, April 25, 2013
Q(W ) =
dH
dt
∝′′q A(t) = ′′q L2
(t) = ′′q (L0 +v t)2
Heat release
rate (W/m2
)
Burning Area, A = L2
Flame spread
velocity
Release rate of energy
and combustion
products
Cumulative Fire
Hazard
≡∆H = ′′q (L0 +vτ)2
dτ
0
t
∫ ≈αt exp βt2
[ ]
α ∝ Q0 = Initial combustion rate
β ∝ (v0/L0)2
= (Initial flame spread rate)2
Initial heated length, L0
Regulation
addresses these
2 fire response
parameters
Simple Compartment Fire Growth Model
13. 13Federal Aviation
Administration
Development of FAA Fire Test for Seat Cushions
CPSC Meeting, April 25, 2013
Fire-blocking Foams or Fabrics Provide an Additional
Minute of Escape Time in a Post Crash Fire
0
0.2
0.4
0.6
0.8
1
0 50 100 150 200 250
Unprotected Cushion
Fabric Fire
Blocking Layer
Foam Fire
Blocking Layer
Noncombustible
Foam
FractionalEffectiveDose
Elapsed Time, Seconds
+ 1 minuteOriginal Escape Time
Full scale test data
Fire growth model
(best fit)
14. 14Federal Aviation
Administration
Development of FAA Fire Test for Seat Cushions
CPSC Meeting, April 25, 2013
10-5
10-4
10-3
160 180 200 220 240 260
BestFitCabinFireModelParameters
Cabin Escape Time, seconds
Combustion (mass loss) rate parameter, α
Surface flame spread parameter, β
Escape Time in a Post Crash Fire is Very Sensitive to
Combustion (Mass Loss) Rate Parameter
…. Because cover fabric is
similar for all tests
15. 15Federal Aviation
Administration
Development of FAA Fire Test for Seat Cushions
CPSC Meeting, April 25, 2013
Development of a Laboratory Test
for Aircraft Seat Cushions
Welded Steel Test Frame on Load Cell 2-min Exposure to Oil Burner
16. 16Federal Aviation
Administration
Development of FAA Fire Test for Seat Cushions
CPSC Meeting, April 25, 2013
Examples of
Residential Oil
Burners
The FAA used modified
home heating oil burners
to simulate the effects of a
post-crash fire on aircraft
seating in a laboratory
(controlled) test
Lennox OB-32
Carlin 200 CRD
Park DPL 3400
17. 17Federal Aviation
Administration
Development of FAA Fire Test for Seat Cushions
CPSC Meeting, April 25, 2013
Test Specimens
• A sample set consists of
– one seat bottom (horizontal)
• 18” x 20” x 4”
– one seat back (vertical)
• 18” x 25” x 2”
• A minimum of 3 sample sets will be tested
• Each specimen will be constructed of the
principal components and assembly of the
production seat cushion
– Foam core
– Flotation material
– Fire block material
– Dress covering
– Seams
• Weakest point of cushion will be exposed
directly to burner flame
• Specimens will be conditioned for a
minimum of 24 hours before testing.
18. 18Federal Aviation
Administration
Development of FAA Fire Test for Seat Cushions
CPSC Meeting, April 25, 2013
Specimen Frame
• Frame constructed of 1”x1”x1/8”
angle steel
• Back and bottom support straps
constructed of 1”x1/8” steel flat
stock
• Frame is welded together
19. 19Federal Aviation
Administration
Development of FAA Fire Test for Seat Cushions
CPSC Meeting, April 25, 2013
Test Procedure
• Record weight of each component (back and bottom
cushion) to the nearest 0.02 pound.
• Align seat frame with cushion according to Chapter 7
• Position seat away from burner flame, fire burner for 2
minutes to warm up
• Position the seat in front of burner flame at 2 minutes
and expose for an additional 2 minutes, then turn off the
burner
• The test is over when the seat cushion has self
extinguished OR after 5 minutes from burner shut-off
• Record the final weight at test termination and
extinguish gently if necessary
• Measure burn lengths on top, bottom, back and front of
each component
• A sample set of 3 tests will be run for each cushion
configuration
• A wire may be used to restrain the back cushion to the
frame as long as the wire does not impede or redirect
the flame
21. 21Federal Aviation
Administration
Development of FAA Fire Test for Seat Cushions
CPSC Meeting, April 25, 2013
Test Criteria
The average burn length may
not exceed 17 inches in any
direction, and 2 out of the 3
samples tested must not
exceed 17 inches
minitial −mfinal( )
minitial
×100 < 10%
Burn Length <
17 inches
• The mass loss is measured for
each test.
• The average mass loss of the 3
tests run can not exceed 10%
of the starting weight.
• 2/3 of tests < 10% Burner
Limit Combustibles
Limit Flame Spread
22. 22Federal Aviation
Administration
Development of FAA Fire Test for Seat Cushions
CPSC Meeting, April 25, 2013
Current Methods of Meeting FAA
Flammability Requirement
• Expandable graphite
• Melamine
• Polychloroprene
• Etc.
Non-woven felts w/ scrim
• Aramid fiber
• PBI fiber
• Panox fiber
• Phenolic fiber
Combustion Modified Foam
FR Foam w/ Fire Blocking
Layer
23. 23Federal Aviation
Administration
Development of FAA Fire Test for Seat Cushions
CPSC Meeting, April 25, 2013
Inter-laboratory Study (6 labs x 3 seats)
Criterion
Burn Length
(flame spread)
Mass Loss
(Combustibles)
Repeatability
(Average within-lab variation)
Reproducibility
(Average between-lab variation)
14% 13%
8% 7%
24. 24Federal Aviation
Administration
Development of FAA Fire Test for Seat Cushions
CPSC Meeting, April 25, 2013
Advisory Material: Seat Cushion Test
• AC 25.853-1 - Flammability
Requirements for Aircraft
Seat Cushions
• Gives advice on test conduct,
sample preparation, burner
calibration, etc.
25. 25Federal Aviation
Administration
Development of FAA Fire Test for Seat Cushions
CPSC Meeting, April 25, 2013
*Fire Test Handbook, DOT/FAA/AR-00/12
April 2000
• This test method evaluates
the burn resistance and
weight loss characteristics of
aircraft seat cushions when
exposed to a high-intensity
open flame to show
compliance to the
requirements of FAR 25.853.
• Test Parameters:
– Burn Length
– % Mass Loss
*companion document to FAR 25.853, Appendix F
28. 28Federal Aviation
Administration
FAA Oil Burner Test for Seat Cushions
ACO Seminar, April 2013
Comparison of Sonic Vs. Park Burner
Seat Burner Comparison
0.00%
1.00%
2.00%
3.00%
4.00%
5.00%
6.00%
7.00%
8.00%
9.00%
10.00%
AirFlex Fireblock Dax
Cushion Type
WeightLossPercentage
Park
Sonic 0¡ Trial 1
Sonic 0¡ Trial 2
3 of each cushion type tested per trial
Combustion Modified
Foam A
Combustion Modified
Foam B
Fire Blocking
Fabric