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Welcome to Lady Be Good.net
A repository for online information about
WWIIs Ghost Bomber |
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Attempting
to simulate the last few minutes of the of Lady Be Good's
final flight in order to extract a
few
pieces of "forensic" information is of course wholly
dependent on insuring that the virtual model, as well as
the simulator platform, are as finely calibrated as possible
in terms of replicating the flight dynamics and environmental
factors that would have naturally been present in life. Many
computer
simulators
and simulated aircraft "look" like the real thing,
but in practice perform quite a bit different than their
real world counterparts. With over a decade of experience
in flight simulation as a passion and hobby,
it would be immediately apparent to us if a particular model's
flight characteristics were improperly calibrated.
Upon compared flight models with published B-24 performance
specifications, searching for available Liberators online,
and downloading
and testing the
flight behavior
of several of them under
a series of varied circumstances, we finally succeeded in
finding a well tuned and accurately modeled B-24D flight
model with
which
to proceed.
Shockwave
Productions (recently reborn
as A2A Simulations), who specialize in producing vintage
military
and WWII aircraft
models
for
commercial flight simulation use, provided the Liberator
that more than met our needs. Their attention to visual
detail is very good, but their commitment
to realistic flight dynamics is where they really shine.
"Absolute
Realism" is the
term they've coined to describe their finely tuned process
of calibrating their virtual aircraft.
Their bundled (multi-aircraft) release entitled "Wings
of Power: WWII Heavy Bombers and Jets" is where
we found the B-24D model we decided to use for our LBG
tests.
Their developers utilized
hundreds of performance charts created by hand from
in-house test pilots to verify their aircraft fly accurately
throughout all flight regimes known to this aircraft. This claim seemed born
out by the tests we performed to see if the model would
act
as the 1944 B-24 pilots manual states it would .
Settings for the number of crew members, their body weight,
pounds of fuel, and bomb load, were fully customizable.
Impressed with the potential of this model, we wouldn't
have proceeded
with our tests had we not felt secure in it's apparent
emulation of realistic B-24 flight characteristics.
To view
a video introduction of this model, see the "Lady Be Good" model intro film here.
The
bundled package in which we found our Liberator, "Wings
of Power: WWII Heavy Bombers and Jets", was originally
designed for "Microsoft
Flight Simulator 2004: A Century of Flight" (commonly
referred to as "FS9", as it is the ninth version
of MS flight simulator). It's successor, "Microsoft
Flight Simulator X" (commonly referred to as "FSX")
is the latest version of Microsoft's heralded
flight simulator software series.
Though Shockwave's B-24D
has recently been made "compatible" with FSX
(we tested the model in both versions), we observed the aircraft performed more realistically in FS9. FSX flight physics were "toned" down to accomodae for increased "eye candy" graphics to the shagrin of many flightsim veterans. We
therefore chose to use FS 2004 (hereafter referred to as "FS9")
to conduct our tests, as it has proven to be model reactive, stable, exhibits higher frame rates and fluidity, and
has a much less bloated interface for control interface, camera switching,
gauge monitoring, and video capture possibilities. These were crucial to maintaining controlled tests at we time ran them.
For
those who are not familiar with the latest
advances in PC simulation software, today's flight
simulators have come
a very long way from the earlier 'primitive" versions of
just a few years ago:
Both FS9 and FSX allow users to fly
to and from anywhere
on Earth. Between tens of thousands of real world airfields you can wander,
across all continents, with perfect magnetic compass and GPS alignments,
and all the while gazing out over a virtual replica Earth's coastlines, environmental surfaces, and elevation mesh.
Most
real world
navigational
VOR's, NDB's, and
ILS approach systems,
and even fully interactive Air Traffic Control systems
are present as well. Finely tuned atmospheric physics reproduce
wind, clouds,
rain,
snow, temperature variation,
dew point, precisely
distributed barometric pressure at altitude, seasonal changes,
and proper sun and moon positions for anytime of day or
year at any location on the planet. These parameters are customizable to any requirements
or individual liking with a few clicks of the mouse.
The
accuracy and complexity of the environmental modeling is
truly remarkable. So good in fact, that many
private and commercial pilots and several departments of the
Pentagon now use MS Flight Simulators for pilot training, advanced navigation theory, and emergency excersises.
Though
Shockwave proudly advertised their "Absolute Realism" guarantee,
just for good measure we decided to put them to the bird to the test
before we expended a great deal of energy running time
consuming test runs. We challenged the flight model to perfom according to the
published B-24 performance specifications,
an example of which is this excerpt from the "Engine
Failure in Level Flight" section on page 100 of the
1944 edition of the B-24 Pilots manual:
We
set the mixture, RPM, manifold pressure, payload, and fuel
load exactly as specified above and climbed to 5000 feet.
Then we killed our two inboard engines. The model's airspeed
gradually
decreased and finally stabilized at precisely the
speed at which the manual states for both 5k and 10k elevations:
152 mph and 143 mph indicated airspeed (IAS) respectively.
Changing the payload, altitude, or any other parameters
changed
the airspeed or vertical drift accordingly. During this
test the Liberator could also not hold altitude very long
at
15k,
just as
described. Descending to 10k we were able to stabilize
altitude at 140mph... but a Liberator must be carefully
trimmed here. At 5,000 ft. though it's crucial that you maintain
at least two running engines.
Losing all but one engine
dooms a Liberator to fall to Earth. Even with no crew and
bomb payload a B-24 just cannot stay aloft very long with one
engine.
We were
so sufficiently impressed with the
model's performances as echoed by
those
predicted
throughout sections the WWII flight manuals that
we felt very confident we had indeed found the right aircraft
with
which to proceed
with our tests.
The
two most rock solid facts concerning the LBG's last few minutes
are uncontestable. First, the aircraft must have passed
almost directly over the position at which Lt. Woravkas
remains were found
in 1960 at 26*54’N, 24*08'E.
His parachute opened but became entangled, so he would have
dropped nearly straight to the ground.
Secondly, the
aircraft impacted the ground
some 14
miles southwest
at 26*42’45.7”N, 24*01’27”E
at an indeterminate
time afterwards. As
the crew apparently thought they were bailing out over the
Mediterranean Sea there is a strong possibility
that the bail out of all nine happened very quickly, within
much less
than
a minute's time, so as to stay together as tightly as possible
and attempt to rally at sea as a group in wait for rescue
the next day. Our
"hands free" portion of the simulation therefore
would begin at Lt.
Woravkas position. In addition to these two irrefutable facts
are a series of other less clear factors that, if reasoned
correctly, add a great deal of import as to how the flight
model should be set up before attempting to run a simulation.
These postulated "known" parameters, if correctly
configured, should contribute much to the success of determining
the "unknown" facts accurately.
Some of the things that could hopefully be gleaned from this
process are:
1. At
what altitude did the bail-out occur?
2. At what speed was the LBG flying at bail out time?
3.
What was the descent rate of the aircraft in feet per minute?
4.
Could a Liberator running on the outboard starboard #4
engine be radically
trimmed
so as to arc to the right, when the torque would
naturally pull it strongly to the left?
5. If such trim could be achieved, would the bank angle
and general attitude of the aircraft at impact match the
crash site evidence?
6. How long after abandonment did the LBG fly alone before
crashing?
7. What was the speed of the aircraft at impact?
8.
If the above questions could be determined with some degree
of accuracy, what other questions or deductions could be inferred
from the data?
Extracting
as much as we could from both the hard evidence and carefully
reasoned judgment, we set up the aircraft for testing with
the following
considerations, flight parameters, and and expected results
in mind:
When the
wreck was first discovered,
the propellers for engines number 1, 2, and 3 were
found to have been feathered (i.e. the blades rotated
to reduce wind resistance). Thus, it was clear that
only engine #4 (the outboard right hand engine), was running
at
the
time of
the
bail
out. Because a B-24 cannot maintain altitude in any configuration
on one engine
alone this would
have
been
the
primary
reason
for abandoning
ship shortly after the failure of the third engine due to
fuel exhaustion. We would therefore run on only engine
#4 from the point of bail out.
The
WWII B-24 pilots manual states that if there is a
failure of two engines on one wing,
the rudder trim should be set to the full extent of the trim
knob in the direction
of the running engines to counteract the aircraft's
natural tendency to pull in the
direction
of the failed engines. It further states that this
configuration will assist in, but not eliminate, the need
to apply pressure
to the rudder pedals in order to maintain a consistent
heading. Interestingly, there is no mention in either
the 1942 or
the 1944 versions of the pilots flight manual of
any procedures pertaining to a three engine failure scenario.
We can only assume this is because it was generally
understood during
pilots training that a Liberator
cannot maintain it's altitude at any flight
level with only one engine operating, and that abandoning
ship then becomes the crew's priority.
We had
hoped by studying the Army investigation photos of
the center flight console (where the trim knobs are located),
we would be able to match the settings as found at
the
crash
site
with those
in the cockpit of our model. Unfortunately, it appears
that these knobs
were touched or altered sometime before the Army investigators
got to the scene
by someone one with Don Sheridan's
party three months before. Sheridan apparently
stated as much
(either in his memoirs or to Mario Martinez while
he was researching his book "Lady's Men") because
Martinez relates that Sheridan was aware of them having been
fiddled with. The Army investigators did not touch the trim
knobs until they were completely
photographed,
but the photos clearly show that they had been touched
fairly recently due to the 15 years of accumulated
dust having been rubbed off on a few places on the knobs.
We have some
other
questions
about this matter which may be addressed in an
update later.
For
our purposes then, we set the rudder trim knobs to
full right rudder (as suggested in the WWII manual for a
two engine failure on one wing), and found that with only
engine
#4
running
there is still a slight
pull
to the
left,
though
interestingly, somewhat reduced
from the torque imposed by having both right
engines running. The only way to stop this leftward
tendency, without applying rudder pedal pressure,
is to turn
the
aileron
trim tab to the right. Not far, but just
a bit. At about 2.3 points to the right ("points" as
read by the
numbers
on
the aileron
trim
wheel),
the
compass
stops drifting left. Though the aircraft steadily
loses altitude on only one engine, it none the less flies
relatively straight this way. However, it takes on a "wounded
bird" kind
of attitude because it's right
wing remains lowered a few degrees and it's nose
is yawed about 3
degrees to the right.
We
decided that this must have been very close to the only
way Hatton
or Toner could have hastily set the aircraft trim so
as
to maintain
relatively
level flight for the time it would take to abandon ship.
We therefore decided to run several parallel simulations,
all with full right rudder trim, but varying aileron
trim
settings
of 2.3, 2.4, and 2.5 points to the right to see
how the Liberator "settled" into the unmanned
portion of it's flight with each configuration.
The
B-24 Flight manual states the following RPM and manifold
pressure settings are to be used to for the given
circumstances listed:
Exactly
how Hatton and/or Toner set the engine settings
for the remaining
engine in the moments after their third
engine
quit cannot be fully determined from the crash
scene evidence because of the previously mentioned potential
tampering with the flight controls and
the fact
that engine
#4 was
ripped from it's housing along with the ends of the cables
connecting it
to the
control
console, which may have altered them
as well when the cables were torn. So where should we
set
our model's throttle controls?
We ran
a couple
of
test
runs, varied
the engine settings,
and
found
that
if
the engine
#4 were throttled all the way up to takeoff settings
the pull to the left
increased quite a bit. Alternatively, throttling
down to normal cruise settings diminished the left hand
pull considerably
but the Liberator begins losing altitude at a
much faster rate. We therefore felt that it would have
most likely made sense for Hatton and/or Toner
to increase the RPM and manifold
pressure up to or just above that of the maximum
climb settings
of 2550
RPM and 46hg . This would
have not only been perhaps "instinctual" for
a pilot to do, but would have made common sense
too. For even though
they
had no
reason
to refrain from running the engine up to it's "War
Emergency" range at that point (the ship was soon
to be lost after all), it was
still presumably going to require a few minutes
to trim her level, prepare for bail out, and exit the
plane cleanly. Knowing that the engine was tired and
almost out of fuel after a dozen or so hours of continuous
running,
and
that
anything
above
2550
RPM and 46hg manifold
pressure is only recommended for brief periods
of flight, it seems likely they wouldn't
have wanted to take chances at that point of
having the engine suddenly "running away" or
falling precipitously by pushing it too hard. There
is also the issue of the increased left hand
torque exhibited by the engine at emergency power,
which
would have made it all the more difficult to hold on
a straight
course by trimming alone. We therefore decided to set
the engine
at 2600
RPM (just a hair above maximum climb power) and
46hg manifold pressure for all our test flights.
From
the fix they got from Benina tower near Benghazi
at
12:12 am. It's
believed the LBG subsequently traveled on a course of
about 150 degrees thereafter. From the position of Lt.
Woravka as it
aligns with the Benghazi area along that same line it appears
they held this course for the next two hours until they were
forced to bail out due to fuel exhaustion. But was the
aircraft at that same heading during
bail
out?
When the third engine quit, could the plane may have drifted
off
course
a bit while the pilots struggled to trim her for bail
out? It seems likely that since the aircraft, now
on one engine, was
still
traveling
at over
two miles per minute, and that bail out procedures would
take a
few minutes to coordinate and execute, Hatton would have
attempted to hold their "last known" course
line because it was presumably going to be the first "line
of travel" that would be flown by the search planes at
dawn. Indeed, the currents in the
Mediterranean might drift them off this line by dawn
anyway, and compared to the immense benefit of being
found in short order the next morning, with Toner in
the cockpit to assist, it would have taken comparatively
little effort to keep the plane
on
course for the last few minutes, therefore maximizing
their chances of being found by search teams. Although there
is no evidence to support of refute any particular
heading for the aircraft at the time of abandonment,
it's likely that they would have attempted to stay on
their original
line of flight for as long as possible. This could have
been accomplished easily by one pilot manually holding the
heading while
the other cranked around the rudder trim to maximum right
rudder, and began to find a reasonably balanced aileron trim
that temporarily stabilized
the
compass drift. Considering these theoretical assumptions
were a reasonably good pilots instnicts, and lacking any
firm evidence to the contrary, we decided to set the heading
at 150
degrees
for
the
start of the simulation. Though this is the most
important aspect of any simulated run, there are a several
other factors to suggest this heading is probably
correct;
we'll
discuss them later in the section Bail
Out: A Question of Wind.
This was
pretty much a no brainer. We removed the weight of all nine
crew members, all bombs (the crew had presumably dropped
them in the sea
after
turning
back from near Naples), and all but 50 pounds of fuel.
This equates to just over over 6 gallons of fuel,
which translates into roughly ten minutes of flight
time for the remaining engine. This is a "guestimate".
All the fuel that may have remained in the tank feeding
engine #4 had completely evaporated by 1959).
The
crash site evidence requires that two parameters be met at
the time of impact. The first requirement is that the aircraft
must not only arrive at or near the location
of the crash site, but must impact the ground at
a heading approximating the alignment of
the impact debris field. Neither Walker, McClendon,
or Martinez however, mention the alignment of either the
LBG or the debris field. We're unsure if it is even mentioned
in the Fuller/Neep
Report. It has been generally referred to having
been found facing "almost due east" with
the debris
field stretching
out
across
the desert directly in front of
it as pictured at right, indicating it rotated
about 180 degrees before coming to a stop. In addition, judging from the angle of the broken tail section (60 degrees to starboard) the rotation was cleary in a clockwise direction.
To
narrow down the heading at impact we studied several
photos of the LBG taken at low sun angles, one on the morning
February
28th, 1959 when Sheridan's party was there, and
another
taken May 24th or 25th, 1959 when the Army investigators
first
arrived. By placing the flight sim model at the
crash site and then setting the date and sun angle to approximate
that
which is seen in the photos, it appears that the
LBG's
nose faces approximately 107 degrees, meaning that
the heading at impact would be the reciprocal of about 287
degrees.
It's
a bit hard to tell however if the debris field
lines
up perfectly with the fuselage itself but it doesn't
seem to be any more
than a few degrees off and perhaps a hair to the
north. We will therefore be looking for an impact heading
of
somewhere
between
275
and 295 degrees ***.
The second requirement is what part of the aircraft can or cannot touch the ground first. Neither wing had any sign of impact to it's tips or underside, nullifying any scenario that allows either wingtip to contact the ground first. Other evidence at the scene strongly suggests that it may have been propeller #4, still running on it's last few drops of fuel, that initially sliced into the ground. Why? The propeller and large parts of it's engine were torn from from the aircraft and ended up scattered in pieces across the debris field. However, the propeller was the most distant obect from the aircraft seen in the debris field, while the nose wheel and several pieces of the bombay doors were much closer to the aircraft, indicating that it was one of the first things to snap free of the plane, perhaps even before the fuselage itself pancaked into the ground. This would also have initiated the significant clockwise rotation that the aircraft experienced during the crash resulting in it's ending up facing some 180 degrees from it's direction of travel, breaking it's tail section before stopping. We will thus be paying close attention to any impact scenario where the bank angle of the aircraft allows prop #4 to impact the ground before the fuselage.
***
If anyone has any hard data as to the exact alignment
of
the LBG fuselage and debris field as originally observed
when first discovered please contact
us and let us know.
We
suspect there was a bit of wind on the night of the
incident, but for the sake of the original set of controlled
tests
we did not load any. Our theory about this is based
on the positions of Lt. Woravka as compared to the
place where
the "Rally Point" items were discovered,
and other associated factors. We
will explore this in more detail in the discussion below entitled Bail
Out: A Question of Wind
So
here we go.
The charts below chronicle the results from
a total of 15 simulated runs at 5 different
altitudes, 3 flights for each altitude.
With
the aircraft configured with the above flight parameters,
we ran each flight from a
point originating
at Lt. Woravka's
position, and repeated this at
each of these altitudes:
5000 ft., 4500 ft, 4000 ft, 3500 ft, and 3000 ft.
We repeated the run
at each particular altitude three times, with different
aileron trim settings: 2.3 points right trim (blue
lines),
2.4
points right trim (green lines), and 2.5 points right
trim (red lines). The results are mapped below in screenshots
overlays taken
from FS9's in-sim flight tracking map. The three
thumbnails below each map
are screenshots taken of the aircraft at
the time of first impact for each respective run.
Moving
your mouse over any thumbnail
will bring up a larger view of the impact screenshot
with the data recorded by the simulator at that moment.
This data contains location, speed, and heading information.
We've color coded
the thumbnail borders to match the corresponding
flight line for the respective
aileron trim settings used in each run. The black
airplane icons are the position at which the Liberator
first reaches
the
ground
for each flight track. The position of
the actual LBG crash
site is marked on each
map for
reference.
After
running and charting these tests we observed the
following:
1.
The first thing that becomes apparent
is how drastically different the flight paths become
by altering the aileron trim by only a tenth of a point.
In all 15
flights
the
aircraft appears to fly relatively
straight for the first minute or so before it begins
"settling" into it's particular descent path.
Either of the three of these aileron trim settings, or
altitudes would have
temporarily appeared to Hatton and/or Toner to have stopped
the compass drift long enough to proceed
with and execute the bail
out routine. In this sense, the final fate of the LBG
having been trimed in a way that preserved
it's structural integrity at impact appears to have been
completely random.
2.
The second is that the scenario
that begins at 3,500 ft. appears to best approximate
the distance required to reach the ground at or about
the approximate location of the crash site. The 3,500
ft. 2.5 trim scenario
in particular (red
line) puts the aircraft nearest to the crash
site of all the tests we ran.
3.
Third, it's clear that the lower the starting altitude, the less pronounced
the tendency to arc to the right becomes for a given
aileron trim.
In other words the flight track straightens or tends
to open more to the left if started at successively
lower altitudes. Why? We presume this to be a factor
of the
slightly increased
air pressure at the lower altitudes allowing for greater
thrust or "grab" from the remaining engine's
propeller.
4.
Fourth, by studying the thumbnails it becomes clear that
almost all the
blue tracks have the aircraft fuselage
hitting the ground simultaneous to, or before prop #
4 does, and that the red tracks from the higher altitudes
show
the
right
wing nearly touching first.
The red track from 3,500 feet however not
only ends up closest to the actual LBG position, but
the bank
angle
of the
aircraft clearly illustrates that prop #4 strikes the
ground first, and
the fuselage and right right wing are equally well off
the ground, just the requirement needed for a substantial clockwise
rotation
to be initiated.
5.
Finally, the "impact heading" requirement further supports
the red track from 3,500 ft. as it comes closest
to the debris field alignment as well. This
track impacted the ground at 308 degrees, just
a bit north of our estimated 275 to 295 expectation.
This is not surprising. Studying the chart for
the chart for the 3,500 ft tests, and it's apparent that
if the aileron trim knob had been set slightly to the left, from the
2.5 setting to say 2.48, that the arc of the
flight would open to the left slightly and the position
of impact would correspondingly move to the south.
Unfortunately
we could not test this trim configuration because the
aileron trim in the simulator model can only be changed
in whole tenths of
a point. The actual trim tabs on a B-24 however, are
linked by a cable that is controlled by linear turns
of the trim knob and could have easily ended up at this
incremental setting.
The confluence of all 5 of these"'required" threads being consistent with the the crash evidence seems very persuasive. We inserted other altitudes and headings from directly over Woravka's position into the simulation for a few days after this, attempting to refute our assumptions, but most parameters starting at Woravka's position and descending in any other direction couldnot fulfill the rquirments needed for the LBG to end up where she was found in the manner she lay.
Accordingly, if the 3,500 ft track is then taken as a close approximation of the Lady's last few minutes, then:
1.
The bail out began at somewhere near 3,800
feet ASL, by the time crew had evacuated the aicraft
it had fallen to around 3,600 or so. This is actually
less than 3,000 feet off the ground, as the Canascio
Plain is about 800-900 feet above sea level.
2.
The speed of the aircraft at bail out
was near 111 knots IAS (128 mph IAS)
3.
The descent rate "averaged" about 300
feet per minute throughout the flight. This number
was slightly
higher at atitude and decreased as the plane
descended. (This varied from an average of 450 fpm
for the 5k red track, to 200
fpm
for
the
5k blue track.)
4.
The
elapsed time (as clocked in the sim) from
Lt. Woravka's position to impact was 7
minutes, 36 seconds.
5.
The speed at impact was approximately 114
knots IAS (131 mph IAS).
An
interesting corroboration to the descent rate we observed
was observed in a close-up view of the vertical
speed indicator (VSI) as
photographed
by the Army Investigators in 1959 in the cockpit of the
Lady Be
Good after several of her gauges had been removed for
study.
VSI needles indicate an aircraft is flying level
when the needle is at the 9 o'clock position, they
move upward
(toward the "10 o'clock" position) when ascending,
and downward (toward the "8 o'clock" position) when
descending. VSI's operate by measuring incremental changes
in atmospheric pressure
inside
a semi-sealed
chamber
with a
sensitive
diaphragm at its center. There is a small "calibrated
leak" allowing air into the chamber from the outside
which expands or compresses the diaphragm
momentarily allowing it to transfer this difference
in air pressure to the indicator needle by way of
delicately calibrated linkages. Because
it takes a moment for the changing
air pressure to enter the chamber,
effect the diaphragm, and transfer the data via the
linkages, there is usually a slight delay in sending
the
data to the
needle.
In addition, because
the internal parts of
a VSI
are quite
sensitive,
it's not uncommon for the
diaphragm or linkages to become damaged during a strong jolt or impact.
This can sometimes "freeze" the
needle at or near the position it was indicating when
the damage occurred. Because this is a sealed gauge
that cannot be tampered with without opening it, it's
very
unlikely
it was
changed
by
anyone
prior
to the photograph below.
Clearly, the
VSI needle
is "frozen" at a
descent rate consistent with the 300 feet
per minute rate we observed, and a compelling corroboration of the 3,500 ft. red track descent rate.
One
of the nagging questions surrounding the bail out of
the crew has been why the "rally point"
where eight of the nine crew rallied and rested after bailout was eventually found to have been at least 4/10th of a mile southwest of
their crew member Lt. Woravka's remains. As the LBG must have passed over Woravka's
position
(because his chute did not open properly and he fell to his death), why had
the crew had land and end up rallying 4/10ths of a mile southwest?
Bail out protocol, as chronicled
in the B-24 pilots manual, calls for the crew to prepare
for bail out by opening the bomb bay doors, the nose
wheel hatch, and the rear escape door, located on the
underside near the tail of the plane. The first to exit
are to be the bombardier (in this case
Woravka),
and then the
navigator
(Hays) through the nose wheel hatch. Then the tail gunner
(Adams) and the left waist gunner (Shelley) are to leave
through the rear escape hatch. Then the right waist
gunner (Moore),
followed by the flight engineer and the radio operator
(Ripslinger and LaMotte) are to jump through the open
bomb bay doors. Finally, the co-pilot and pilot (Toner
and Hatton) through the bomb bay doors as well.
Had they
followed this protocol, Woravka would have naturally been
the the first crew member to leave the plane. Had they
all followed shortly thereafter, even at an interval
as tight as 3 seconds a piece, the bail out would have
taken 24 seconds to achieve, during which time the LBG, flying at 111 knots would have covered nearly a mile
of ground.
At
first glance one might postulate that the LBG was traveling
at a heading towards the southwest in it's final moments,
and that this could explain why the rally point items
were found where they were. The two problems with this
scenario however are that, first, had the crew bailed
at this heading they would have presumably assumed
that Woravka could be found northeast of them, and therefore
would
have logically walked in that direction a bit farther
before
deciding
to head northwest towards the coast. The second problem
is that if the LBG was headed in a southwesterly
direction at the time of bail out, the bank angle
required for the aircraft to reach the crash site and
impact propeller #4 first could not have occurred as
it would have taken on more of a level winged attitude,
impacting the fuselage either before or simultaneous
to prop #4, and thus not experiencing the torque
seemingly required to
support
the skidding 180 degree clockwise rotation observed at the crash scene.
These
anomalies can be readily explained however if a light
wind from a generally NE direction were present at the
time. But can this be verified? We searched
for meteorological records of seasonal winds in central
Libya and found that the NOAA database extends
back to 1949. Using the wind
data from
this
year
(and nearly identical trends from later ones) a seasonal
pattern is clearly evident. This data shows
thaw the predominant surface winds at the bail out location
for March
thru April are generally "light winds" from
the NE to ENE. The average speed of these winds can even
be estimated
from the
java based applet at the Columbia University web site
that hosts the data. We've charted and interpreted the
months in question here: NOAA
Libyan Winds Database - 1949. Granted, though no one
can be certain of what the exact weather conditions
actually were on the Calanscio Plain on
the night of April 4th, 1943, the historical
data
clearly suggests that light NE winds were certainly not
uncommon.
With
this in mind, adding
an 11 knot wind from the NE into the scenario suddenly
explains a great deal of the bail out anomalies, as illustrated
in the graphic below:
If
the the above wind factors were actually in play,
how would it effect the
unmanned
descent
of the
LBG in the simulation?
We
ran a few
more more
test runs to see. We entered an 11 knot wind from 50
degrees into the simulation and ran four test runs
varying in starting altitude from 3700 down to 3400 feet.
The 3600 foot test run results are charted below:
This
run impacted the ground only 0.53 Miles NE of the actual
position of the LBG, the closest impact observed in all
our testing.
Considering
the plethora of variables that obviously existed on
the night of the crash, (fuel load,
weight load, throttle, trim, engine performance,
atmospheric pressure, wind, etc.) it would be extremely
presumptuous
to assume that we had resolved the truth of the Lady's
last minutes. The assumptions of accuracy
that we attempted to input into
the simulation were based on informed conjecture,
nothing more. It's tempting to think that some of the
data
gleaned can be understood outside the envelope of reasonable
doubt, but it can of course never be verified. That
said,
the simulation results tend to
nonetheless support, rather than refute, at least
some of the evidence of the crew's bail out positions,
and evidence observed at the crash site nearly 50 years
ago. Ultimately, it can never be known exactly WHAT
happened and exactly
HOW
things
went
down
on the
night
of
the crash, but perhaps a few tidbits of reasoned conjecture
may be in evidence from our exercise.
In
all our testing...(gee wiz folks, sorry)...we seemed
to have neglected to
film a video of the last few
seconds of flight. Sheesh. So here
it is. Unfortunately, the simulator model
is not imbued with
any "crash physics".
Too
bad too.
Because it would help diagnose many questions about the
geometry of the
impact itself (a complex topic we may devote a future
discussion to). Notice however how the #4 engine propeller touches the ground first. The belly of the fuselage has not impacted the grount yet. Simple physics dictate this would have thrown the aircraft into a clockwise rotation resulting in the "inverted' heading in which the wreck was found, and is consistent with thefuselage "nose bending", the tail breakage, and other damage evidence.
The
video "pauses" briefly at the exact moment of impact
to scan around the aircraft, so as to examine it's attitude
in relation to the ground at this moment. It then continues
into the ground, although without the
suddenely initiated clockwise rotation that
would have been present in life after prop #4 strikes the ground. Most of the focus
here is on on the flight
gauges, sense of aircraft speed, and angle
of impact, etc.....
LBG Impact Video
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