A GA Pilot’s Perspective On Flying The Space Shuttle

by Jim Hanson
Published in Midwest Flyer Magazine – Aug/Sept 2016

In the June/July 2016 issue of Midwest Flyer Magazine, I shared my experience flying a King Air 200 to Cape Canaveral, simulating a space shuttle landing on the 15,000 ft. runway. Upon landing, we toured the Cape, and got a briefing as to current NASA projects.

Prior to our visit, my brother, Bob, and I had the opportunity to fly a space shuttle simulator – an experience described here.

My sponsor called at 7 p.m. and said that if I could come out to the Cape at 2:00 a.m. the next morning, he could get another pilot and me on the simulator for a couple of hours. I didn’t have another pilot available on short notice, but did have my non-pilot brother, Bob. We went out to the Cape, where they were doing configuration changes on the simulator. They needed someone to just fly the thing while they did the work, and it wasn’t anything on which any of the astronauts could get valuable training, as they practice as an entire crew. The simulator was an accurate replication of the entire multi-deck crew quarters, as NASA simulates EVERYTHING on the mission, even things as small as stowing things in drawers, to keep surprises to a minimum.

The simulator is what the simulator people call six-axis of motion simulation, capable of roll, pitch, yaw, as well as combining these actions to simulate G-forces, deceleration, and less than 1 G feelings. It has full visual simulation, from side windows all the way around. The simulator looked like the cockpit of an airline jet, but with more overhead switches. Even the flight instrumentation was the same (Columbia was later updated to a “glass cockpit,” replacing mechanical gauges). Some major differences were: control sticks instead of wheels, a “side stick” on the left side of the cockpit that operated the dive brakes and allowed the craft to fly laterally without tipping the wings. The airspeed indicator/Mach meter went to Mach 28, and the altimeter readings started at about 350,000 feet! The “distance to go” readings on the Horizontal Situation Indicator went to 9,999 miles, instead of 999. The area where engine instruments would normally be displayed was given over to flight management displays, much like the newer airliners. These displays could display energy management and energy reserves, as well as checklists, procedures, crew advisories, and systems diagnostics.

The simulator is not capable of simulating a launch, and launches are fully automatic, unless an abort back to Kennedy would occur (the least likely occurrence, since loss of a main engine only a few seconds after liftoff allows either abort to Spain or to proceed to orbit).

The simulator is initiated at main engine cutoff (about 90-100 miles high), with a metallic “BANG” (separation of main tank), and a slight deceleration. The shuttle “coasts” into orbit from there.

The visuals on the simulator were stunning, with Earth below, and the black of space above. Landmasses were easily identifiable, and seemed to be proceeding in slow motion below. I was enthralled by the spectacular effects, and the instructor asked if I would like to fly the vehicle.

In space, all movement is by reaction-control rockets, as there is no aerodynamic control. With a limited supply of reaction-control fuel available, control movements are normally kept to a minimum to conserve fuel, but this was a simulator – I kept telling myself! – with an unlimited amount of fuel. I tried roll and pitch maneuvers, and found I was prone to introduce PIO (Pilot Induced Oscillation), but could manage if I concentrated. The instructor asked, “Are you a helicopter pilot?” I replied that I was, and asked why he had asked. “You’re doing a great job,” he said. “Most people over-control.”

I found that once I  put in a control input (roll, for example), the craft would continue rolling forever. To stop the roll, an equal amount of opposite roll was required, and if you overshot, a roll back in the original direction would stop the vehicle just where you want it. It flies a lot like a helicopter – no stability, and the proper procedure is to put in a control input, then take it back out.

We were flying very nose-high relative to the Earth. “Does that bother you?” asked the instructor. “We find that about half of the pilots are bothered by flying nose-high… it is unnatural for an airplane.

“We could just roll inverted, and it would be like doing an inside loop around the earth, but we need to have our payload bay doors open and pointed toward the Sun (they are solar collectors/heat dissipaters), so we can’t do that.” He grabbed the attitude indicator on the instrument panel, and turned it upside down (not something you can do in an airplane), so that we were now flying “nose down” according to the instrument. “Feel better?” he asked. “We put that in for the pilot’s comfort.”

While “in space,” my brother, Bob,  got to play “payload specialist.” We explored the cabin, and on the back of the cockpit were several “windows” looking back at the payload bay. On the side of the payload bay was the “Canadian Arm,” built to do the heavy lifting in space. It is so lightweight that it cannot support itself in the 1 G gravity of Earth, but can maneuver large items in orbit.

Bob’s “mission” was to grab a satellite with the arm, and place it in orbit. The arm can be controlled in several ways – with a computer keyboard (L-R, up-down), or with a joystick. Punching “operation” on the keyboard un-stowed the arm, and pre-positioned it to pick up objects from the payload bay. Everything in the payload bay was stark white against the blackness of space, but we knew that there was only a short time to accomplish the “mission” as we were in low Earth orbit and would shortly be in total darkness in the Earth’s shadow.

Bob maneuvered the arm with the joystick–and a lot of coaching from the instructor–to the “grab handle” fastened to the satellite. Once there, he inserted his fingers into a small bowling-ball type device (since replaced with a “grab trigger”). This device controls the mechanical “fingers” of the arm, and pressure exerted on the arm is proportional to the amount of pressure the astronaut exerts on the trackball. He picked up the satellite, cleared the payload bay, and released it into orbit.

For the landing, we turned the tail towards the direction of flight, and fired retro-rockets in the vicinity of Guam to slow our speed and drop us from orbit (at the time, all shuttles were landing at Edwards. NASA wanted more experience before attempting a Cape landing). We did a “somersault” to go nose-first again. Though the shuttle has full auto-land capability (it has five computers that continually monitor the flight, and the computers will automatically “vote” to exclude any computer that doesn’t agree with the rest), most pilots elect to hand-fly all or part of the approach and landing. Afterall, how many of these space landings do you get to make? I hand-flew it, following the cues on the Collins FD-109 flight director (the same model used in many corporate jets) for lateral and pitch guidance.

The descent profile is initially shallow, then goes to about 40 degrees (plus or minus 2 degrees) during the critical portion of the re-entry, then shallowing again. Too shallow, the vehicle skips back into space; too steep, it burns up. Since it followed the first flight of Columbia, this simulator had the ability to depict the heating of the windshield and front-fuselage structure, as they found it was disconcerting for the pilots to watch the structure turn cherry red, then give off “plasma flares.”

These plasma flares look (at least in the simulator) like flaming bits of jellied napalm tearing away from the structure. It is not part of the structure, but part of the thin atmosphere itself that is energized and dissipated. This phenomenon is responsible for the “communications blackout” on re-entry. In any case, fire in your windshield is not what most pilots would like to see. No matter how much you concentrate on your instrument scan, you can’t help but watch the plasma flares!

At about 350,000 feet, the first indications of Earth’s atmosphere become apparent. The altimeter starts to wake up, the Mach meter comes off the peg at Mach 28, and the spacecraft starts to exhibit aerodynamic buffet. The flight profile calls for banks from left to right to “load” the craft with G forces to dissipate energy. Things are happening fast. The last 6,000 miles of re-entry – from retro-fire to touchdown – take only about 30 minutes.

The drill for landing at Edwards is to approach the California coast at Mach 5, cross Edwards at 50,000 feet at Mach 2, make a 270-degree turn, and land – all in about 7 minutes. The glide angle seems improbably high, but then I remembered that the glide angle is only about 3.7-1. By comparison, most general aviation aircraft are in the 8 or 10 to 1 glide ratio range.

The craft scrubs off speed all the way down, to a final approach speed of 240-270 knots, depending on weight. During the last 3,000 to 5,000 feet of altitude in the approach, pilots can experience “ground rush,” as the ground comes up suddenly. There are no landing flaps to deploy, but raising the nose on the delta-wing craft causes huge amounts of drag.

The landing gear goes down about 12-15 seconds before touchdown, at an altitude of only 300-400 feet. With the delta wing, little or no flare is needed, as it builds a big ground cushion of lift underneath. Just hold the attitude you have until touchdown. Touchdown occurs at about 185 kts (200 mph), and a drag parachute is deployed.

We had about 15 minutes left in our time window, and the instructor asked if I’d like to try it again – this time with more wind. Through the magic of simulation, we repositioned up to 150,000 feet and Mach 7.5, and tried it again. This time, the glide angle looked REALLY steep, and it was. Thirty-five knots of wind is the limit for landing the shuttle except for emergency conditions, because if the wind is higher than 35 knots, the pilots may not see the landing area over the nose in the final phase of landing.

I am grateful to have been able to fly the simulator, especially now that Columbia is gone, because we were using the actual telemetry data to replicate Columbia (the only shuttle to have flown in orbit at the time). Astronauts say that all of the shuttles fly differently due to their mod status, weight (Columbia was the heaviest of all the shuttles), and built-in idiosyncrasies. It was an interesting exercise for a pilot that flies jets, gliders, and helicopters, using techniques from each of the three aircraft types. In aviation, you never know when some seemingly unrelated bit of knowledge will help you out. Who would have thought that glider and helicopter flight skills would help fly a space shuttle?

EDITORS NOTE: Jim Hanson is the long-time manager of the Albert Lea, Minnesota airport. Even before this flight, people often described him as “spacy.” If you would like to bring Jim “down to Earth,” he can be reached at his airport office at 507-373-0608, or via email at jimhanson@deskmedia.com.

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