On December 1, 1984, NASA and the Federal Aviation Administration (FAA) conducted the first remotely piloted air-to-ground crash test of a transport category aircraft. The Full-Scale Transport Controlled Impact Demonstration (CID) was the culmination of 4 years of effort by the two agencies. NASA and the FAA had many objectives during the joint planning and execution of the Controlled Impact Demonstration. The structural loads experiment was very successful. Ninety-seven percent of the channels were active at impact. The data is still being assessed. Only a portion of the data is presented here; approximately 80 channels of data are available. Analysis of the remaining data is in progress. Interior photography was also very successful. One hundred percent of the cameras functioned. The film contains unique information on the development of fire and smoke in the interior of the aircraft. From a human tolerance point of view, the CID was simulation of a survivable crash

Hayduk, R. J.

English

NASA Technical Reports Server

CID OVERVIEW
Robert J. Hayduk
NASA Langley Research Center
Hampton, Virginia
NASA/FAA Government/Industry CID Workshop
NASA Langley Research Center
April I0, 1985
https://ntrs.nasa.gov/search.jsp?R=19860012463 2020-03-20T14:56:51+00:00Z
INTRODUCTION
On December i, 1984, NASA and the Federal Aviation Administration (FAA)
conducted the first remotely piloted air-to-ground crash test of a transport
category aircraft. The Full-Scale Transport Controlled Impact Demonstration
(CID) was the culmination of 4 years of effort by the two agencies. NASA and
the FAA had many objectives during the joint planning and exeqution of the
Controlled Impact Demonstration. NASA's interest was primarily structural
crashworthiness. The FAA's primary interest was the demonstration of an
antimisting fuel additive's performance. Demonstration of improved crashworthy
design features was a secondary objective for the FAA.
This workshop is intended to provide results obtained to date on the
performance of the airframe structure and the associated structural loads from
the CID test to the industry/university/government community.
C.I.D. OBJECTIVES
The major C.I.D. objective for the FAA was the antimisting kerosene (AMK)
experiment with the modified fuel system. The FAA had a great deal of success
during the developmental tests of the AMK and spent a lot of effort at Dryden
implementing the fuel degraders and cooler systems for the AMK. However, this
workshop is not going to address the AMK experiment. We will concentrate on
the NASA structural baseline data experiment that provides information for our
future composite structure dynamics program. We are going to describe the
crashworthy design features that both NASA and the FAA have onboard the
aircraft.
• Verify antimisting fuel (AMK)performance
e DemonstrateoperationalAMKfuel/propulsion systemcapability
eAcquire structural baselinedatafor composite
structures program
e Test improvedcrashworthydesign features
C. I. D. FUSELAGE INSTRUMENTATION
This figure shows the instrumentation that we had on the fuselage for the
structural loads experiment. The wings were also very heavily instrumented. The
structural instrumentation details are presented in reference i. This data, along
with the data from the seats and dummies that were on the aircraft, will be the
principal data presented at this workshop.
400
600J 540
1220 1120 820 960
B.S. 400 540 600J 820 960 11201220 N, T
ul I_ i_ C.G.o oil _i ol o[] I'1 In I-I I-I 1-1 I-1. _F1 _] __ "_[] i I D IQ _1Q Q
o Biaxial (N, L)D Triaxial (N,L,T)
Typical strain gage I Strain gagebridge
bridge
IMPACT SURVIVABLE SEATS
The majority of the seats onboard were FAA sponsored seats. Those seats
are described in reference 2, and reference 3 presents the results of the FAA
seat experiments. The two NASA seats onboard the aircraft are described in
reference 1 and results are given.
5
OBJECTIVES
The primary objectives of the workshop are to release, in preliminary
fashion, the results of the structural loads data that we obtained from the
C.I.D., and also to release the data on the seats, dummies, restraint systems,
galleys, bins, and flight data recorders.
The most important purpose of this meeting is to interact with the user
community. This is just a preliminary release of data; we would like to make
sure that when we complete our data reduction analysis and report that we address
the important questions that you help us raise.
• Preliminary releaseof structural loadsdata from CID
• Preliminary releaseof dataon seats, dummies, restraint
systems,galley, bins, and flight data recorders
• Interaction with user community
6
LANGLEY C.I.D. RESPONSIBILITIES
Langley C.I.D. responsibilities were primarily for the structural in-
strumentation experiment. Langley developed a data acquisition system and
photographic system to cover the impact with both general data and photographic
coverage of the interior of the aircraft. Langley was responsible for the
acquisition of the impact loads, the data reduction and analysis, and correlation
with the analytical models that have been developed using the DYCAST computer
program.
ost ructural instrumentation
ODataacquisition system- hardware/software
olnterior photocoverage
olmpact loadsacquisition/analysis
oAircraft analytical modelling
7
PLANNED C.I.D. IMPACT SCENARIO
This is a brief description of the planned C.I.D. impact scenario. Barber
(ref. 4) goes into more detail. Basically, we were trying to impact in front of
the AMK wing openers so that the structural loads impact experiment would occur
prior to impact with the wing cutters. We were expecting about 17 feet per second
vertical sink rate and longitudinal velocity of 150 knots.
• Gross weight: 175-195,000pounds
+0 +0
• Sink rate: 17_2 FPS • Longitudinal velocity: 150 -5 knots
• Glide path: 3. 3° to 4.0°
Frangible -_ ....
landing lights A,_ AMK wing openers
C.I.D. PLAN VIEW
The interior of the aircraft had a large number of seats onboard with
data acquisition systems fore and aft. Photographic coverage throughout the
fuselage was provided by Langley (i0 cameras) and JPL (i camera). Two nose
cameras were installed by Dryden to assist the ground-based pilot. JPL in-
stalled a camera on the vertical stabilizer looking down on the fuselage and
wings. Ground-based and airborne photographic coverage was provided by JPL.
Note that two longitudinal location identifiers are marked on the plan
view. The usual body station (BS) system is used, as well as a longitudinal
X-coordinate measured in inches from the nose of the aircraft.
la Battery pallet [DAS] /
/ //
_Power pallet [camera/lights] / /
Flight recorder _/
z_Camera and range [10 locations] ----7/ / /
_ _'/ / I
/-/- Restroom
Galley_ __Galleydoor // /, _ervice _X_,Closets_// ///--7
Restroor_--_-.\ //// / La°°r-_'___ /// /
°'7-R'__ v"°_ _ .,^^.'X.recorders
{_3_) seat_\ BSn "_.x_O "x\ \ 1_0 '-Main door",_._
_, Main\ (- \x \\ x
_n door_ x L750,f_---.._ 1110
v. u 410 __
\ \\
a Lights [camera] B Flight attendant seats
B FAA seats _Data acquisition sys. pallet
_I NASA seats [] Taperecorder pallet
C.I.D. IMPACT SEQUENCE
This sequence of four scenes from a Hulcher camera shows the sequence of
events. The primary period of times that are of interest to this workshop are
the left wing impact and the impact of the fuselage with the ground. By the
time the aircraft impacted the wing cutter, the NASA structural loads experi-
ment was essentially over. However, there were substantial loads that
occurred during impact with the wing cutters that are of interest to the seat
experimenters. After the aircraft came to rest and was engulfed by fire, the
structural and seat loads experiment was over. However, there were some
fire-resistant materials experiments onboard, such as seat fire-blocking
layers and heat resistant window panes.
_!tmpact with wing openers
10
C.I.D. VERTICAL FLOOR ACCELERATIONS
The next four figures give a very brief overview of the structural loads
data. On these figures, acceleration (G's) is plotted as a function of an X
coordinate, which is simply the distance measured from the nose aft in thousands
of inches. Vertical acceleration peaks in the neighborhood of 14 to 15 G's
occurred in the nose and forward cabin, substantially dropping off to levels of
7 to 2 G's in the remainder of the fuselage. It was a very, very mild impact
from a human tolerance point of view. I believe a fit, young adult male could
withstand upwards of 25 G's in a vertical direction for short durations. The
C.I.D. aircraft had fairly low levels throughout, which would have been tolerable
by a fit and well restrained human.
The peaks from the data are represented by the squares. The plus symbols
represent an average peak which is determined by a triangularization technique
described by Fasanella (ref. 5). These average peaks correlate very well with
the peaks from the actual filtered data, except perhaps in a few instances where
high frequency oscillation occurs.
FuselageimpactT = 0.5 sec.
14 _ [] []PeakG
12-
+ Twiceaverage
10-
Accel. 8 -, + 4-
G'S 6 - _ o
+
4- _ , r_
2- []
I I I I I I
0 0.2 0.4 0.6 0.8 1 1.2
(Thousands)
X--coordinate,inches
11
C.I.D. LONGITUDINAL FLOOR ACCELERATIONS
Longitudinally, the acceleration distribution throughout the aircraft was
fairly low. Again, the highest levels occurred in the nose and forward cabin,
dropping off substantially below 4 G's down around the 2 G-level for most of
the aircraft.
FuselageimpactT = 0.5 sec.
14-
12- m PeakG
10- + Twiceaverage
Accel., 8-
G'S [] []
6-
4- D
2-+ + § n. g+ _ m []
I I I I I I I
0 0.2 0.4 0.6 0.8 I 1.2 1.4
{Thousands)
X-coordinate,inches
12
C.I.D. TRANSVERSE FLOOR ACCELERATIONS
Transverse accelerations along the floor were also generally low -- 5 G's
in the nose, down around 2 G's for the remainder of the aircraft.
FuselageimpactT= 0.5 sec.
14- o PeakG
12- + Twiceaverage
10-
Accel., 8-
G's 6-
[]
4-
2- 13
m rh
I I I I I I
0 0.2 0.4 0.6 0.8 I 1.2
(Thousands)
X-coordinate,inches
13
AIRCRAFT STRUCTURAL RESPONSE
Load transmission from the fuselage bottom up to the dummy is discussed in
reference i. This figure introduces the levels at one particular body station.
Point B is body station 540, about 410 inches back from the nose. The
fuselage bottom experienced about 32 G's at impact. By the time the load got
up along the side wall and under the floor, the level was reduced to around 7
G's. On the floor and in the pelvis of the dummies, the vertical acceleration
was down to 6 G's.
Dummy
Floor
Subfloor
0 Fuselage
Vertical 24 l bottomypmca!=mpact pulseload T "
(g) 16 5 sec
8oL
A B C
Fuselage location
14
C.I.D. SUMMARY
In summary, the structural loads experiment was very successful. Ninety-
seven percent of the channels were active at impact. The data is still being
assessed. Only a portion of the data has been presented here; approximately
80 channels of data are available. Analysis of the remaining data is in progress.
Interior photography was also very successful. One hundred percent of the
cameras functioned. The film contains unique information on the development of
fire and smoke in the interior of the aircraft. From a human tolerance point of
view, the C.I.D. was a simulation of a survivable crash.
1. Structural loadsexperimentwas successful
o97% of channels active
• Databeing assessed
2. Interior photographysuccessful
• 100%of camerasfunctional
• Significant information
3. CID survivablefrom impact loadspoint of view
15
REFERENCES
I. Alfaro-Bou, Emilio: NASA Experiments on the B-720 Structure and Seats. Full-
Scale Transport Controlled Impact Demonstration, NASA CP-2395, 1986, pp. 29-47.
2. Johnson, Richard A.: Controlled Impact Demonstration Seat/Cabin Restraint
Systems - FAA. Full-Scale Transport Controlled Impact Demonstration, NASA
CP-2395, 1986, pp. 49-60.
3. Cannon, Mark R.; and Zimmerman, Richard E.: Preliminary Floor, Seat, and Dummy
Data. Full-Scale Transport Controlled Impact Demonstration, NASA CP-2395, 1986,
pp. 125-155.
4. Barber, Russ: CID Flight/Impact. Full-Scale Transport Controlled Impact
Demonstration, NASA CP-2395, 1986, pp. 17-28.
5. Fasanella, E. L.: Digital Filtering and Acceleration Pulse Interpretation.
Full-Scale Transport Controlled Impact Demonstration, NASA CP-2395, 1986,
pp. 103-123.
16


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