Rotisserie mode referred to having to put the ship into a very slow roll, wing over wing, to even out the shuttle’s exposure to the sun’s ferocious heat in airless space. This would prevent one side of the vessel from baking while the other side remains frozen in the hot side’s shadow.
“Rog, AC. We concur on remaining in stable minus-Z during your terminal phase initiation. We’re looking for TPI and rendezvous over the states at about ninety-nine minutes, MET.”
“Mother agrees, Flight. We should be closing on the target at mission elapsed time of ninety-seven and one-half minutes.”
“Thanks, Jack. So how’s the ride, right seat?”
Enright turned his face from the right television screen to the three windows wrapped around his helmeted face.
“Incredible simulation, Flight! This is just breathtaking. Nineteen minutes out of KSC and I’m looking down on Rabat, Morocco! The old clock on the wall here says 9:20 in the mornin’ Houston Time, and we’re flying upside down over Morocco where it’s 3 o’clock in the afternoon. Truly amazing! The terrain is pretty hazy. With the sun’s sub-point about forty-five degrees west of us, the sun angle is too shallow for very much detail below. But there is no doubt that Morocco is very pink, red almost. It’s just bizarre to sit here heads-down with Rabat out my forward window and Casablanca just over my right shoulder. Casablanca! ‘Of all the gin joints in all the towns in all the world… What a morning, Flight! And I can see the eastern shadows off the Atlas Mountains extending into Algeria!”
“Sorry to interrupt the tour, Jack, but we’re going to lose you in about two minutes over Algeria. You’re about eleven minutes from first sunset. We’re hoping that’ll cool you off enough for the flash evaporators to carry the heat load. Next comm by IOS when you cross Kenya in fourteen minutes.”
“Okay, Flight. Next AOS by Indian Ocean Ship in fourteen.”
“And, Endeavor, for your burn pad, we have Day Zero de-orbit burn times for Edwards: De-orbit Rev One, BT at 00:52:18; Rev Two, burn in at 2 hours, 25 minutes, 18 seconds; Rev Three, BT at 03:59:08; Rev Four, burn at 05:33:12; Rev Five burn in at 07:06:44; and Rev Six, BT at 08:41:21. Your de-orbit burn times for landing at Kennedy, Day Zero follow: Revolution One, BT 58 minutes plus 51 seconds; Rev Two, at 02:33:17; Rev Three at 04:07:49; Rev Four, BT at 05:42:17; Revolution Five at 07:14:49. Then KSC de-orbit Rev 15 at ignition time of 21 hours, 39 minutes 04 seconds; and Rev 16, BT at 23:11:58.”
“We got it, Flight. You getting our PM downlink in doppler tracking?”
“Affirmative, AC. Solid lock. Starting to breakup slightly as you go over the edge at twenty-two minutes.”
“Roger, Houston. Catch you by IOS. Endeavor is right and tight up here.”
“Copy, AC. Configure LOS Madrid at…”
“And we’re on our own again, Number One.”
The copilot nodded as he watched the mountainous border between Morocco and Algeria pass overhead beneath his upside-down office.
“MPS inerting and purge is complete, Will.” Enright studied his green television which told him that Shuttle’s three main engines were safed and clean of explosive fuel vapors.
Two and a half minutes from Morocco, Endeavor coasted silently over the Fazzan Oasis in Libya. A glance out the thick window revealed a lush speck of green the size of a fingernail far below, which tracked its 25-second transit across the window. Shuttle sped at 17,500 miles per hour over the arid pink wastes of central Africa, over Libya and Chad, bound for the Sudan only 150 seconds southeast of the Libyan oasis. Chad’s 11,000-foot-high Tibesti Massif pointed snowy peaks toward Endeavor’s white body.
Both pilots startled when a Caution and Warning siren wailed in their earphones. At the center top of the main forward instrument panel, a yellow caution light glowed at one of the 40 annunciator lamps. In front of each pilot on the glareshield overhanging the instrument panel, a Master Alarm light flashed red. Parker pushed his Master Alarm pushbutton light, which extinguished the alert tone but not the RGA yellow caution light on the annunciator’s second row of eight lights.
“Rate gyro assembly!” Enright called.
“Run it down, Jack.”
Enright scanned the system failure checklists which he called up on the right television screen. He summoned the proper checklist by tapping a coded sequence of numbers into his computer keyboard unit on the right side of the center console by his left thigh. The wide console separated his seat from Parker’s.
“Looks like RGA Number Three, Skipper. Damn.”
“Take ’er out, Number One.”
“Rate gyro assembly Number Three, Overhead Panel-16, off. RGA secured.”
The yellow caution light went out.
“One down, three to go,” the AC said dryly as Endeavor skimmed over the Sudan’s deserts 100 miles west of Khartoum, only 30 minutes away from Pad 39-A, now more than 8,000 miles behind Endeavor.
Shuttle’s four Rate Gyroscope Assemblies, now reduced to three, work together with the ship’s inertial measurement units to feel Endeavor’s position and attitude in space. One rate gyro disabled was a serious but not critical failure. Two lost would be dangerous; three down would dictate an emergency landing at the first opportunity. And four out of four lost would be all she wrote as a doomed crew struggled to bring home a 200,000-pound glider by the most basic of scarf and goggles flying by the old turn-coordinator and air-speed indicator.
“Take a minute outside, Jack,” the AC said calmly to break the tension. “Reckon we can spare the gas to crank her around for a minute.”
The Colonel powered up the Rotational Hand Controller between his knees and set the ship’s Reaction Control Systems to Pulse Mode.
Nudging the control stick toward his right knee, the command pilot fired a minuscule, pre-programmed burst from the RCS jets in the right OMS pod in Shuttle’s tail. Two RCS jets popped loudly like cannon and shot a 30-foot flame past the ship’s tail section.
Endeavor’s upside-down nose rotated smoothly clockwise as she would be viewed from the ground. She made a half circle flat on her back. As the nose swung toward 180 degrees after 60 seconds, another pulse from the two RCS thrusters fired with 870 pounds of thrust from each jet. Endeavor’s slow rotation stopped as the starship came about flying tail-first. With her nose looking back across Africa along the track already covered, Endeavor’s cockpit faced west toward the rapidly setting sun. Thirty-two minutes out, Shuttle rode backward over the 13,000 foot peak of Mount Amba Farit in Ethiopia 75 miles northeast of the capital Addis Ababa.
From the upside-down flightdeck, the crew had a 200-degree panoramic view through the six forward windows of their first sunset in space.
“Take a look, Jack.”
“God, Skipper,” Enright breathed with his face and open mouth close to the wide windshield.
Below, the arid mountains of Africa’s east coast were already in darkness. Far to the west, the sun sat blindingly white just at the hazy blue horizon above the Sudanese desert. Within half a minute, the white globe sank into the horizon’s ribbon of pale atmosphere. The sun flattened as if its upper and lower limbs were squeezing out the middle of the solar disk. The Earth’s far western corner exploded into gold and orange. And after a final dazzling burst: darkness, the moist and star-filled blackness of nighttime in heaven.
“Remember that to tell your grandchildren, Jacob.”
The copilot of Endeavor could not speak.
“Endeavor, Endeavor. Greetings from the Seychelles Islands. We have solid downlink. How you read by IOS?”
“Ah, with you Indian Ocean. Jack and I are fine at thirty-four minutes. Blew an RGA a while back.”
“Copy, Endeavor, we’ll look at it. You’re over Mogadiscio in Somali. You cross the Equator in two minutes. We see you flying in minus-Z, tail first. Be with you six minutes this pass. We show you thirty-five miles behind the target and 40 below it.”