Funding Source: Pro Bono
Funding Period: May 2006 – July 2006
Principal Investigator: Gerardo Olivares PhD. – [email protected]
Project Monitor:Quinn Kanaly – National Geographic Documentary Producer
Research Overview: The objective of this project was to evaluate for the National Geographic Chanel (Documentary: Undercover History: Where is Amelia Earhart?)
whether or not Amelia Earhart would have survived ditching her aircraft
in the Pacific. Activities included the development of a finite element
model of the Lockheed Electra and the simulation of the ditching event
using ALE techniques. Upon completion of the work a survivability
assessment and photorealistic rendering of the numerical model were
submitted to the documentary producers.
World Flight 1937
In July 1936 Amelia took delivery of a Lockheed L-10E Electra financed by
Purdue
University
and started planning a round-the-world flight. This would not be the
first to circle the globe, but would be the longest at 29,000 miles
(47,000 km) since it would follow a grueling equatorial route.
Through contacts in the
Los Angeles
aviation community Fred Noonan was eventually chosen as navigator. He
had vast experience in both marine (he was a licensed ship’s captain)
and flight navigation. Noonan had recently left Pan Am, where he
established most of the company’s seaplane routes across the Pacific.
He hoped the resulting publicity would help him establish his own
navigation school in
Florida. On St Patrick’s Day, 1937, they flew the first leg,
Oakland,
California to
Honolulu,
Hawaii. The flight resumed three days later but a tire blew on takeoff and Earhart ground-looped the plane. Severely damaged, the aircraft had to be shipped to
California for repairs and the flight was called off.
The second attempt would begin at
Miami,
this time flying east. They departed on 1 June and after numerous stops
in South America, Africa, the Indian subcontinent and Southeast Asia
they arrived at
Lae,
on June 29.
On July 2, 1937, at midnight GMT Earhart and Noonan took off from Lae. Their intended destination was
Howland
Island, a flat sliver of land 2000 meters long and 500 meters wide, 10 feet (3 m) high and 2556 miles (4113 km) away.
Their last positive position report and sighting were over the Nukumanu
Islands, about 800 miles (1,300 km) into the flight. The U.S. Coast Guard cutter
Itasca
was on station at Howland, assigned to communicate with Earhart’s
Lockheed Electra 10E and guide her to the island once she arrived in
the vicinity.
Through
a series of misunderstandings or errors (the details of which are still
controversial), the final approach to Howland using radio navigation
was never accomplished, although vocal transmissions by Earhart
indicated she and Noonan believed they had reached Howland’s charted
position, which was incorrect by about five nautical miles (9 km), over
scattered clouds which are said to have cast hundreds of island-like
shadows on the ocean.
After
several hours of frustrating attempts at two-way communications,
contact was lost, although subsequent transmissions from the downed
Electra may have been received by operators across the Pacific.
The United States government spent $4 million looking for Earhart. The air and sea search
by the Navy and Coast Guard was the most costly and intensive in
history at that time, but search and rescue techniques during that era
were rudimentary and planning was influenced by individuals wary about
how their roles in looking for an American hero might be reported by
the press.
Many
researchers believe the plane ran out of fuel and Earhart and Noonan
ditched at sea. However, one group (TIGHAR —The International Group for
Historic Aircraft Recovery) suggests they may have flown for two and a
half hours along a standard line of position, which Earhart specified
in her last transmission received at Howland, to Gardner Island (now
Nikumaroro, Kiribati) in the Phoenix group, landed there, and
ultimately perished. TIGHAR’s research has produced a range of
documented, archaeological and anecdotal evidence (but no proof)
supporting this theory. The third theory suggests Earhart flew to the
for pre-war recon intelligence after not finding Howard, then either
taken hostage by the Japanese and later killed in Saipan or returned to
the
US
under new names.
[source text :http://en.wikipedia.org/wiki/Amelia_Earhart and http://news.nationalgeographic.com/news/2003/12/1215_031215_ameliaearhart.html; source images google earth].
History of Flight
On
July 1st, 1937, at 6:35 am (Local Time) Earhart and Noonan took off
from Lae in a Lockheed Electra L10E, registration number NR16020. Their
intended destination was
Howland
Island. Their last positive position report and sighting were over the Nukumanu
Islands, about 800 miles (1,300 km) into the flight. The U.S. Coast Guard cutter
Itasca
was on station at Howland, assigned to communicate with Earhart’s
Lockheed Electra 10E and guide her to the island once she arrived in
the vicinity. 0843 IST, Out of Fuel 100 miles of Howland (radio signal
strength).
Ditching Conditions:
– July 2nd 1937
– Departure Fuel: 1100
gallons à 1092
standard 6-pound
U.S.
gallons
– Flight Conditions:
0418 GCT, Airplane: 140 knots (161.1 mph)
– Head Wind: 23 knots (26.5 mph)
– Average True Airspeed: 134 mph
0843 IST, Out of Fuel 100 miles of Howland (radio signal strength), [30 feet deep minimum depth]
– Cabin Conditions:
Two-point restraint system
Remote control box for the Bendix receiver located at eye level
– Possible Ditching Conditions (Per Lockheed Electra 10 E Flight Test Data Page 2 Report 467 Nov 12 1935):
– Case I (Optimum case controlled flight ditching conditions):
· 60 mph
· Water 30 feet plus depth
· Flaps Landing Position
· Landing Gear Up
· Power on
– Case 2 (Worst case controlled flight ditching conditions):
· 80.7 mph
· Water 30 feet plus depth
· Flaps up
· Landing Gear Up
· Power off
– As shown in the deck log of the Coast Guard cutter Itasca the conditions prevailing in the area of
Howland
Island at the time the Earhart plane disappeared were:
· Sky condition – “bc” (Blue sky with detached clouds)
· Visibility – “9” (Prominent objects visible above 20 miles)
· Wind – “2” (11.3 knots)
·
Sea
State – “1” (Moderate swell from ESE)
– Aircraft Weight:
Empty Weight: 3219 kg (7100 lbs)
Pilot Navigator: 131 kg (130 lbs 160 lbs)
Cargo: 191 kg (422 lbs)
TOTAL: 3541 kg (7806 lbs)
[Source: *Weight data from Lockheed Electra 10 E Specifications Form EE1135 Rev 5-1-36]
Analysis Model Description:
– Explicit Finite Element Model with Euler Lagrange Coupling (LSdyna)
– Aircraft: Lagrange rigid body with the appropriate mass and cg location
– Air: Eulerian Formulation
– Water: Eulerian Formulation
– Water depth: 30 ft according to data for minimum depth in the vicinity of
Howland
Island.
Ditching Event Simulation Results:
This acceleration field will be used in the occupant simulation.
Virtual Reality Ditching Event Visualization:
Photorealistic Virtual Reality Ditching Event Visualization:
Based on the finite element model results a photorealistic VR simulation was created at NIAR’s VR Center.
Multibody Occupant Model:
Based on prints and pictures of the actual aircraft a model for the cabin interior was created for analysis.
Amelia Computational Model Biomechanical Responses:
Amelia Computational Model Kinematics:
Data Analysis and Conclusions:
- Lap Belt Forces:
One of the areas of concern would be the strength of the 2 point lap belt anchor locations. Per CAA, Airworthiness requirements of air commerce regulations. Bulletin No 7A, effective July 1, 1929:
According
to the simulation results the maximum force applied to the belt anchor
locations is 1907 lbf. Although this is a dynamic load there is a
possibility of lap belt failure. If lap belt failure occurred the
occupant would be unrestrained 3 seconds into the event, and would
sustain fatal injuries.
- Egress:
According
to data provided by a newspaper article regarding the ditching of
Lockheed Electra 10 E, the plane stayed afloat for about eight minutes
before it sank.
Let’s assume Amelia had 8 minutes to egress the aircraft:
According
to the Biomechanical data obtained in the analysis, she would have had
not suffer any incapacitating injury to the head, neck, and thorax
area. Note that the simulation results can not establish the injury
risk for the upper and lower extremities. Due
to the airplane configuration the only path to the Life raft would be
through the Pilot Escape Hatch and accessing the aircraft through one
of the side doors.
There are various factors that could prevent Amelia from opening the door to the life raft area:
- Water Pressure
- Structural deformations of the door frame
- Locking Mechanisms
- Any injuries sustain to the upper or lower extremities
Conclusion
Based
on the analysis results the ditching event should be classified as a
survivable accident. A survivable accident is where sufficient cabin
structure and seats remain to aid survival of one or more occupants,
and where further loss of life is the consequence of drowning, or other
post- crash incidents.
Providing
that there was no lap belt failure and that she was able to egress the
aircraft, unless she was rescued within hours of the crash event she
would have been exposed to the elements without any survival gear. More
likely she would have drowned.
From the Aviation Institute of Aviation Research: http://www.niar.wichita.edu