T-38A Pilot ReportBy Buck Wyndham, Major, USAFR
The T-38 is one of those rare airplanes that, in my opinion, looks perfect from every angle. When I was a child, I built a plastic model of it, and I spent many happy hours making it swoop, roll and dive its way through my house. One of my dreams was to fly this beautiful airplane for real. Years later, I got the chance to do so, first as a student pilot, and later in my career, as an US Air Force Instructor Pilot for two consecutive tours. I've moved on to become an airline pilot now, but I still fly the T-38 about a dozen times each month as a Reserve Associate Instructor Pilot for the Air Force Reserve. Sometimes I have to pinch myself to see if this all a dream. I'd like to share with you some of my impressions on flying the "White Rocket."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. The crew chief helps you strap in, connecting your G-suit while you thread the shoulder straps, crotch strap, and parachute "key" onto the tongue of the right lap belt. The tongue is inserted into the receptacle on the left lap belt until it clicks, then you tighten everything down. Your helmet goes on next, then you connect your oxygen hose and communication cord. You and the airplane have become one. 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.  Leveling off at 16,000 feet in your designated practice area, you check the oxygen system, pressurization, fuel quantity and balance, G-suit and altimeter. Everything looks good, so it's time to have a little fun. You push the throttles to MIL and lower the nose to build airspeed. The wind noise around the canopy increases steadily, as does the pitch sensitivity of the stick. At 10,000 feet and 500 knots indicated airspeed, you squeeze your leg and abdomen muscles, then smoothly bring the stick back until the G-meter (or your backside) says "5." The back-stick force required is approximately 30 pounds. The Gs press you into your seat and the blood tries to drain out of your brain. As the nose slowly tracks up past the vertical position, the altimeter is spinning like a fan and the Gs begin to subside as the airspeed decreases. You're over the top, inverted, at 20,000 feet, with an airspeed of 200 knots. You have just gained 10,000 feet in a matter of about 15 seconds. You pull the nose down to the 45-degree nose-low point, unload to about zero G, roll rapidly upright, and pull up to level flight at 400 knots, completing half of a "Cuban Eight." How about an aileron roll? You raise the nose 5 degrees and move the stick to the side about 4 inches. The world rotates smoothly around over your head and back below you again. Next, you do the same thing again, only this time you move the stick to its full deflection, causing your head to snap violently the other direction as the roll rate increases instantly to 720 degrees per second. At two rotations per second, it is very difficult to time the aileron neutralization to arrive perfectly wings-level again. You overshoot by 30 degrees, but there's a wide grin forming under your oxygen mask.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
December 1999  |
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