The above photo shows dramatically the ejection of CAPT
Chris Stricklin of the Thunderbirds ejecting from the
Thunderbird 6 on September 14, 2003 at
Mountain Home AFB, Idaho during the "Gunfighter Skies,
2003" airshow. The photo was taken by SSGT Bennie J.
Davis III, an Air Force photographer stationed on the
observation deck of the control tower. SSGT Davis snapped
the shot as he already had realized something was seriously
wrong as the F-16 was not lined up on the show line, but
instead headed towards the tower. Although it appears
from the photo that the plane is threatening the cars
in the background, that is an artifact of the long
lens used by SSGT Davis. He was using a Nikon D1X with
a 300mm lens. The photo was taken at 1/1000 or 1/2000
of a second. The cars are actually about a half mile
behind where the aircraft impacted the ground.
CAPT. Stricklin had taken off into a maneuver called a
Reverse Half Cuban Eight. He pulled up into a sharp
climb, rolled inverted, and then pulled over the top
into a partial loop. Unfortunately he based his safety
calculations on an incorrect field altitude, and was
unable to safely end the maneuver. On realizing the
aircraft was unrecoverable he turned the aircraft slightly
away from the show line, and then ejected. He initiated
ejection with his left hand at 140ft of altitude, with
a descent rate of about 8400 feet per minute. His airspeed
was about 225kts which is about 260 miles per hour.
Technically this was probably an out of envelope ejection
due to the high descent rate and low altitude.
Upon actuation the initiators on the seat sent hot gas out
to the canopy jettison system. The canopy was released and
rockets ignited pushing it up and back to where the airflow
helped tear it off the jet as it reached the point where
the hinges release. After the canopy had moved about ten
feet away from the jet a pair of lanyards attached to the
canopy caused the egress system to continue its sequence
by having hot gas directed back into the seat via another
hose on the other side. This gas initiated the catapult.
This is a ballistic charge, akin to a large shotgun shell
that drove the rocket section of the ROCAT and pushed the
seat up the seat track assembly until the point where a
port was unmasked allowing hot gas to enter the rocket
section and ignite it. The rocket then continued driving
the seat up the rails and out of the cockpit. This took
some time, perhaps about four tenths of a second, during
which time the aircraft continued to descend. The seat
left the aircraft at somewhere around 50-75 feet of
altitude above the ground.
CAPT Stricklin suffered only minor injuries due to the
ejection. The aircraft was destroyed. Analyzing the
photo gives some interesting insight into the ACES II
ejection sequence. The following photo is a blow up of
the center of the photo. It shows the seat atop the flame
from the three rockets of the seat, the CKU-5 Rocket
Catapult (main propulsion), the STAPAC (STAbiliztion
PACkage, keeps the seat from pitching excessively), and
the Yaw rocket. The seat appears to be no more than four
feet above the cockpit rails, and is already clearly yawed
slightly to the left. This is to help clear the vertical
tail. The blur over the pilot's helmet is the parachute
box that has just been mortared off the seat. The mortar
fires at 0.2 seconds after seat sequencer is activated by
a striker near the top of the cockpit rails (seat track
assembly). This indicates that the photo was taken only
a few hundredths of a second after that time period. The
headbox shape is pretty clearly visible with the pitot
tubes protruding on either side of the top, and the flaps
on the bottom are slightly spread as the parachute shroud
lines are begining to be extracted from the stowaged
tunnels on the inside of the flaps. The white blur
above the left knee appears to be notes or maps blown
loose by the relative wind. CAPT Stricklin's body
position is nearly optimal for the ejection, even
though analysis of the downlinked video from in the
cockpit shows that he initiated ejection with his
left hand while his right was still on the Flight
Control Stick. As the canopy jettisoned he moved
his right hand to the seat firing handle.
Other images show the aircraft sliding on the ground
as seat separation occurs. This would be about 0.45
seconds after sequencer start, hence if CAPT Stricklin
had delayed even a half second, he would likely not
have survived the mishap. The Goodrich ACES II seat
worked exactly as expected, and saved the pilot in
a situation that would have been fatal for any earlier
generation seat. The mortared parachute allowed for
the pilot to have a fully deployed parachute which
decellerated him to a safe landing speed despite the
low altitude and high sink rate of the ejection. The
seat selected Mode 1 based on the pressure of the
relative wind as measured by the pitot tubes on each
side of the headrest compared to the ambient pressure
from the Environmental Sensor Unit (ESU) on the back
of the seat. In this mode the sequencer orders the
parachute deployment nearly immediately, allowing
for exceptionally fast recovery of the airman.
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