T-38A Pilot Report
By Buck Wyndham, Major, USAFR
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Let's
start with a walkaround inspection. Access to the T-38 cockpit is usually
gained by use of a sturdy ladder that hooks over the edge of the canopy.
After climbing up and storing your in-flight publications and instrument
approach plates in the map case on the right cockpit sidewall, you hang your
helmet on the right canopy rail where it will be out of your way until you
get strapped in. Still standing on the ladder, you lean into the cockpit and
turn on the battery, then check the fuel and oxygen quantity, landing gear
lights, and cockpit warning lights. The battery switch is selected
"off," then you check the aircraft's maintenance forms to ensure
the plane is ready to fly. Everything looks good, so you stow the forms under
the seat. Since you'll be doing a little bending and stooping during your
preflight inspection, you take off your parachute and lay it on the ramp to
make sure you don't damage it or accidentally catch the D-ring on something. The
walkaround begins at the left engine inlet and continues clockwise. You check
the usual items, paying special attention to the condition of the
honeycomb-composite flight control surfaces and wingtips. These items can be
easily damaged, and are often the first things that show cracks or buckling
from being overstressed. Other areas of interest are the wing attach points
and landing gear side-brace trunnions, both of which are left unpainted so
they can be inspected for cracks. At airshows and other public showings of
the airplane, many people notice that the tires look as though they are worn
out and frayed. This is because the tires are made of multiple layers
containing white-colored cords, with the final, inner layers containing red
cords. After a couple of landings, multiple layers of white cords are
exposed. This is completely normal, and the tires may be safely used until
the first red cords are showing. The landing gear doors and speedbrakes are
left open after each flight so that the next pilot can inspect the hydraulic
actuators and other items in these areas. The
landing gear pins and pitot tube cover are stored in the fueling access panel
below the left engine inlet, and the Angle-of-Attack (AOA) vane
locking-device (about the size of your fist) is stored in the left-hand
cockpit storage compartment. At this time, the grounding wire is unplugged
from the nose and moved away from the airplane. Before
I strap in the airplane, I always walk to a spot in front of the nose and
look at the overall "Big Picture." I do this not only as a final
check of the condition of the plane, but also because I really enjoy looking
at the sleek lines of the machine that is about to launch me into the blue.
It's hard to believe that the Talon was designed more than 40 years ago. Its
tapered waist, razor thin wings and long, graceful fuselage are timeless
design features, and it will always be a prototypical "fast jet"
image in the minds of many airplane lovers. The excitement level begins to
mount as you strap on your parachute and climb the ladder. You step onto the
seat cushion, then you lower yourself into a sitting position in the small
but comfortable cockpit.  For better or worse, the T-38A's "round-dial" instrument panel (seen here) has now been replaced with a modern, all-glass cockpit in the T-38C. In this writer's opinion, the "A"-Model T-38 was pure magic.
You
turn on the battery and run through your cockpit instrument and system
checks. Since the plane is so simple, this only takes about one minute. Most
of the switches are already in the proper position; you're just verifying
that they're correct. You turn on the radio and call Clearance Delivery for
your departure clearance, then monitor Ground Control for the engine start. The
T-38 has no self-start capability; it needs a supply of pressurized air to
rotate the engines. This air is supplied by a "huffer" unit
or palouste, which is connected via a large hose to a manifold on
the bottom of the airplane, near the left engine. During start, the ground
crewman must manually switch the air to the other engine after the first one
is started. We're ready to start, so you give the crew chief the
"air" signal by raising your arms over your head, making a fist
with your left hand and slamming it into your right palm. The air rushes into
the right engine, and a rising whine begins as the RPM increases. At 14% RPM,
you signal that you're ready to start. You reach down with your left hand and
press the right engine start button, then move the right throttle to idle.
Light-off and spool-up are quick, and the engine is stable at idle RPM less
than eight seconds after ignition. The crew chief moves the air diverter
valve to the left engine, and you start it the same way. You check the caution-light
panel to make sure the engines and related systems are operating correctly,
then the ground crewman disconnects the air hose.  Next, you run through a series of flight control checks with the ground crewman. He insures that the control surfaces move the way they are supposed to, the main landing gear doors have closed, the speedbrakes close properly, and the horizontal stabilator moves to its proper takeoff setting. This completed, you check the flight instruments, cockpit indicators, and navigation gear. The ground crewman removes the wheel chocks on your signal, and it's time to taxi. Ground Control clears you for action. The
T-38's nosewheel steering system is activated by holding down a rather stiff
button at the base of the stick. As you add power to start rolling forward,
you squeeze the button hard. Full pedal deflection turns you smartly away
from the parking spot, and you check the heading indicators to make sure
they're turning. While taxiing out to the runway, you review the Takeoff and
Landing Data (TOLD), which you wrote on your knee-mounted data card before
leaving the squadron's Operations building. Specifically, you look at four
numbers and commit them to memory: The Minimum Acceleration Check Speed (the
speed at which you should be traveling when you are a certain distance down
the runway, usually 2000 feet. This number validates all the other numbers,
and ensures you have a normally-performing airplane); the Go/No-Go Speed
(where you decide to continue the takeoff or abort); the Refusal Speed (the
highest speed you can attain and still theoretically stop in the remaining
runway length); and the Single-Engine Takeoff Speed (the minimum speed you
need in order to take off after an engine failure.) Such cautiousness is
required by the military's many years of operational experience with the
Talon, and from the experiences of many pilots no longer with us -- whose
ignorance of these numbers lead to their demise. You're
at the end of the runway. Tower clears you for takeoff. You reach up
with your left hand and grab the edge of the canopy frame, lift it slightly,
then pull it down as your right hand moves the right sidewall-mounted locking
lever forward. The canopy locks with a satisfying clunk, and the red
"Canopy" light on the instrument panel extinguishes. Almost
immediately, you feel a slight "fullness" in your ears as the cabin
pressurization system goes to work. Taxiing into position on the runway, you
turn on the pitot heat and transponder, and check the heading system again.
Now the fun begins.  You point the nose down the runway, letting the plane roll forward slightly until the nosewheel is exactly straight. Now you stop and pump the brake pedals a few times before standing on them as hard as you can. You push the throttles up to the Military Power setting and wait impatiently for the engine instruments to stabilize. The brakes require a lot of effort to hold to hold the T-38 stationary at MIL power, and after 5 seconds, your legs are already beginning to tire from the effort. A quick check of the gauges, and it's time to blast off. You simultaneously release the brakes and shove the throttles past the MIL power detent and into Afterburner. The plane jumps forward, somewhat slowly at first, then with a sudden kick as the 'burners ignite. The initial acceleration in afterburner is about like that of a high performance sports car, but once past 90 knots, the acceleration rate greatly increases. Like most jets, "the faster it goes, the faster it goes faster." There is little or no engine noise in the cockpit. During the takeoff roll, you note the passing of each of the critical performance numbers, each one a milestone toward liftoff. At 135 knots, you begin applying back pressure to the stick, and at 160 knots, you lift off. The acceleration continues. Immediately
after liftoff, you raise the gear and flaps to avoid over-speeding them. More
acceleration. 240 knots comes quickly, and you pull the engines out of afterburner,
slowing the acceleration somewhat. You keep the nose low, only 3 or 4 degrees
high, until 300 knots, then raise the nose to 12 degrees to keep the speed at
the 300-knot legal maximum below 10,000 feet. (The T-38 has a waiver to the
usual 250-knot limit.) At this point the altimeter begins a rapid upward
climb. On cold days, using only the normal non-afterburner climb schedule,
I've observed a sustained climb rate of over 12,000 feet per minute for the
initial portion of the climb. A full-afterburner climb at 300 knots results
in a calculated initial climb rate of 30,000 feet per minute. At that rate,
the altimeter needle spins one full rotation every two seconds. The controls
are well-harmonized and glass-smooth, responding to the slightest movement in
a natural, pleasing way. Pitch forces are fairly heavy in the Talon,
especially at higher G levels, but this trait helps to prevent inexperienced
student pilots from over-"G"ing the airplane any more than they
normally try to do already.
The
T-38 can be flown throughout its performance envelope, from aerobatics to
patterns and landings, with barely any use of the rudder. With the landing
gear retracted, only 6 degrees of rudder deflection is available, and in the
landing configuration, 30 degrees is available. Like
an arrow, the Talon goes where it is pointed, not where it is banked. This
means that turns are accomplished by banking in the desired direction (thus
placing the lift vector where the plane needs to go) and pulling the nose to
the desired point. To lower the nose to gain airspeed for an aerobatic
maneuver, it is simpler and more comfortable to roll the plane upside down,
pull the nose down to the desired pitch, then roll it upright again. Stalls
are quite unconventional in the Talon. Unlike most training airplanes, the
T-38 does not exhibit a normal "stall break" and nose-drop at the
stall. Instead, the pitch attitude remains almost level, and the Angle of
Attack and airframe buffet both increase dramatically. If the stick is held
aft, and the recovery is not initiated, the plane enters an un-commanded
"wing rock" of up to 60 degrees of left and right bank. In this
level, wing-rocking attitude, the airplane sinks nearly vertically at decent
rates of well over 6,000 feet per minute. Proper recovery takes full
afterburner, a good deal of pilot finesse, and plenty of altitude. Because of
this unusual stall trait, student pilots in the Talon are given plenty of
instruction in recognizing and recovering from the approach-to-stall. The
T-38 is not approved for spins.  Supersonic
flight in the T-38 is almost a non-event. Usually, you enter it from a
shallow dive beginning at approximately 32,000 feet. Although it is possible
to exceed Mach 1.0 using Military power in a steep dive, it is far more
expeditious to use afterburner. You set up a 10 degree dive, then ease the
throttles forward over the hump. You observe the nozzle position indicators
swing, indicating the 'burners have lit, and watch the Mach window on the
airspeed indicator. 0.91...0.94...0.97... The airplane is stable and smooth.
Somewhere around 0.98, the vertical speed indicator, airspeed indicator and
altimeter briefly rise and fall, spiking "out of synch" with their
previous trends. This is evidence of the bow wave passing over and moving aft
on the pitot tube. Next, as the Mach increases from 0.99 to 1.03, there is a
subtle change in the way the stick feels. It becomes slightly more stiff, as
if an autopilot servo had become engaged somewhere in the control system.
This vague stiffness remains constant as you accelerate. You are now
supersonic. You look around, half-expecting to see... something. But all is
calm and quiet. No warped stars. No Elvis sighting. But it's still special
and rare. Sacred, in some way. While
the manual states that the aircraft is capable of approximately Mach 1.3, the
aircraft is blasting across the practice area at an amazing clip, so you
limit yourself to Mach 1.15 for 60 seconds or so, feeling out the stiff
controls and analyzing how the airplane feels during a steep turn and an
aileron roll. The far end of your reserved corridor of airspace is rapidly
approaching, and you are out of room for anything more. You gingerly pull
each throttle out of afterburner, one at a time to avoid a flameout, then
raise the pitch to 10 degrees nose-high. Decelerating through Mach 1.0, you
note the same brief fluctuations in the pitot-static instruments. And then
it's over. You're back to the drab, plain world of subsonic -- the world
everyone else in the world lives in. The fuel gauges show that it's time to
go home. You extend the speedbrakes and pull the throttles to idle, resulting
in a descent rate of over 15,000 feet per minute at 300 knots. The
landing pattern is entered from "initial," an upwind leg over the
runway at 1,500 feet and 300 knots. At midfield, you crisply roll into a 65-
to 70-degree bank and pull the airplane around a 180-degree turn, losing 70
knots of airspeed and arriving on the downwind leg with approximately one
half-mile spacing from the runway. Abeam the landing zone, you lower the
landing gear and flaps, then push the power up to maintain around 200 knots.
At the "perch" point, 45 degrees past the runway threshold, you
roll into a 45-degree banked turn, lower the nose about 5 degrees, and begin
pulling the airplane around the final turn. The T-38 has an unusual airframe
buffet at its optimum final-turn Angle of Attack (AOA). New Talon pilots must
develop a feel for this phenomenon, and must cross-check their airspeed, AOA
and vertical speed carefully to avoid developing a dangerous sink rate during
the final turn. Once established on final, you adjust your speed to 155
knots, plus one knot for every 100 pounds of fuel in excess of 1,000 pounds.
For example, with 2,500 pounds of fuel on board, the desired final approach
speed is 155+15, or 170 knots. This speed is adjusted upward for gusty winds,
or no-flap configurations. (The speed for no-flap approaches is 170 knots,
plus the additions mentioned above.) There's
another oddity you'll notice when landing the T-38: On final approach, your
aim point must be approximately 450 feet short of the runway threshold.
Approaching the threshold, you shift this aim point ever so slightly to a
point about 500 feet down the runway, smoothly bring the throttles to idle,
and flare very slightly. This technique results in a threshold crossing
altitude of about 20 feet, and a landing approximately 500 to 800 feet down
the runway. Once on the ground during a full-stop landing, the nose is raised
slowly (and carefully, to avoid hopping the aircraft off the ground) to a 12
degree nose-high aerobrake attitude. This is a more effective way to slow
down than using the Talon's rather weak wheel brakes. The nosewheel is
lowered to the runway at 100 knots. The normal landing distance is between
4,000 and 7,500 feet, depending on pilot technique, condition of the runway,
and flap position. A heavyweight no-flap landing on a wet runway can easily
consume more than 9,000 feet of runway, a fact which severely limits your
options under such conditions. Most T-38 bases have a
"rabbit-catcher" web barrier on at least one of their runways,
which gives significant peace-of-mind to pilots who might, due to various
factors or malfunctions, expect a long landing roll. Back
at the parking area, the Crew Chief places chocks around your main tires, and
signals for shutdown. You release the throttle gate, pull up on the
finger-lifts, and pull the throttles to the 'cutoff' position. As the engines
spool down to a graceful stop, you take off your helmet and let the warm
breeze blow across your face. You don't want to climb out quite yet, so you linger
for a moment, savoring the view of the pointy nose ahead of you, and the
petite wings protruding from the fuselage far behind you. The Crew Chief
smiles, but doesn't ask any questions. The
Talon is truly one of the great airplanes of our time. It is a timeless
beauty, and has performed superbly for over four decades as an advanced
trainer in several air forces around the world, as well as a test support
vehicle, chase ship, companion/proficiency trainer, light attack/fighter
trainer, airshow performer, and privately-owned personal rocketship. While
not a complex or difficult airplane to fly, it nevertheless has some unique
flight characteristics that demand absolute precision and discipline from its
pilot. More than 50,000 student pilots have received their Air Force wings in
the Talon and, with the old airframes now being refurbished and reborn as the
T-38C, many thousands more will get to experience the thrill of riding the
"White Rocket" in the decades ahead. Buck Wyndham, Major, USAFR  |
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