BY JUSTIN RAY
Follow the countdown and launch of the Orbital Sciences Pegasus rocket with NASA's Space Technology 5 micro-sat demonstration. Reload this page for the very latest on the mission.
FRIDAY, MARCH 17, 2006
WEDNESDAY, MARCH 15, 2006
Workers are heading home after a long day of countdown activities and the post-scrub operations. The troubleshooting will resume in the morning.
NASA says next Tuesday, March 21, is the earliest possible date for rescheduling the Pegasus launch of Space Technology 5, given a variety of factors, including available slots on the Western Range and the weather outlook. But the 21st is highly tentative and no date has been booked on the Range yet.
1600 GMT (11:00 a.m. EST)
Slung beneath a modified L-1011 aircraft, the 55-foot long Pegasus rocket departed Vandenberg Air Force Base in California before dawn this morning bound for a spot over the Pacific Ocean west of Monterey for the sunrise launch.
Stacked inside the nose cone of the Orbital Sciences-made rocket rode NASA's Space Technology 5 micro-sats. The 55-pound birthday-cake-size craft will test whether such tiny satellites can be used in monitoring the impacts of solar storms on Earth.
Countdown clocks were targeting a 1427 GMT (9:27 a.m. EST; 6:27 a.m. PST) release of the Pegasus from the Orbital Science "Stargazer" jet to begin the $130 million ST5 mission.
At about T-minus 45 seconds, the rocket technician aboard the aircraft -- known as the launch panel operator, or LPO -- activated the battery that power the Pegasus' first stage aerosurface fins during flight. The fins are used to steer the rocket during its initial climb to space.
Next, retention pins that held the fins in place during the ferry to the launch zone were supposed to disengage, allowing the fins to undergo a final pre-flight "sweep" test to show they were working correctly.
But something prevented the starboard fin pin to retract.
"The pin pullers were told to pull out and unlock the fins. But we were not able to get motion on the starboard side," said Omar Baez, the assistant NASA launch manager for ST5.
"PLT, can do you do maneuvers for stuck pin," the launch panel operator (LPO) aboard the L-1011 requested to the aircraft pilot.
"LC, PLT, we're doing stuck pin maneuvers now," the pilot radioed to the launch conductor on the ground.
"Roger that," the launch conductor replied.
A chase plane flying alongside the L-1011 relayed live video of the carrier aircraft banking its wings left and right in a rolling motion in hopes of freeing the stubborn locking pin.
The additional attempts to retract the pin where unsuccessful, leading to the immediate launch scrub.
"This is LC, abort, abort. This is LC on mission freq(uency), abort, abort," the launch conductor instructed the team.
"PLT copies abort."
"LPO copies abort."
There was scant time to wrestle with the problem. The restrictive life span of the fin battery means a Pegasus rocket must be launched within about 90 seconds of activation to ensure a safe margin during flight. Otherwise, the launch has to be aborted and the battery replaced. That is what happened today.
The launch team safed the rocket, and the L-1011 returned to Vandenberg within a half-hour of the abort to begin troubleshooting the locking pin problem.
"It could be something mechanical, it could be ice, a number of things," Baez said of the possible culprit.
Meanwhile, ground crews will replace the expired fin battery, a job that will take 48 hours and push the next launch attempt to Friday at the earliest.
But a new launch date hinges on the time required to fix the pin issue and booking a new reservation on the Western Range schedule at Vandenberg. The Air Force-operated range provides tracking, safety and communications services for all launches from the base, plus ground tests and other military operations. Whether Friday could be made available for Pegasus was not immediately clear this morning.
1500 GMT (10:00 a.m. EST)
1446 GMT (9:46 a.m. EST)
1441 GMT (9:41 a.m. EST)
1433 GMT (9:33 a.m. EST)
The L-1011 is now returning to Vandenberg Air Force Base for troubleshooting of the pin retraction problem.
There is no estimate on when the next launch attempt could be made. At a minimum, the expired fin battery has to be replaced and the pin issue fixed.
1430 GMT (9:30 a.m. EST)
1428 GMT (9:28 a.m. EST)
1428 GMT (9:28 a.m. EST)
1427 GMT (9:27 a.m. EST)
1426 GMT (9:26 a.m. EST)
With the batteries activated there is just 90 seconds to launch today or else an abort will be called. That is due to the limited life of the batteries.
In the final moments prior to release of Pegasus, the L-1011 carrier aircraft crew will oversee the last seconds of the countdown and flip the switch that will drop the vehicle, with the ST5 spacecraft aboard, from the belly of the jet.
1425 GMT (9:25 a.m. EST)
1424 GMT (9:24 a.m. EST)
1423 GMT (9:23 a.m. EST)
1423 GMT (9:23 a.m. EST)
1421 GMT (9:21 a.m. EST)
1419 GMT (9:19 a.m. EST)
1417 GMT (9:17 a.m. EST)
1413 GMT (9:13 a.m. EST)
1411 GMT (9:11 a.m. EST)
1410 GMT (9:10 a.m. EST)
1409 GMT (9:09 a.m. EST)
1407 GMT (9:07 a.m. EST)
1359 GMT (8:59 a.m. EST)
1357 GMT (8:57 a.m. EST)
1355 GMT (8:55 a.m. EST)
1345 GMT (8:45 a.m. EST)
1335 GMT (8:35 a.m. EST)
1327 GMT (8:27 a.m. EST)
1326 GMT (8:26 a.m. EST)
1324 GMT (8:24 a.m. EST)
1323 GMT (8:23 a.m. EST)
1322 GMT (8:22 a.m. EST)
1317 GMT (8:17 a.m. EST)
1311 GMT (8:11 a.m. EST)
1306 GMT (8:06 a.m. EST)
1302 GMT (8:02 a.m. EST)
1257 GMT (7:57 a.m. EST)
1251 GMT (7:51 a.m. EST)
1250 GMT (7:50 a.m. EST)
1248 GMT (7:48 a.m. EST)
1231 GMT (7:31 a.m. EST)
1148 GMT (6:48 a.m. EST)
The jet's engines are scheduled to be started momentarily. And in a little while the aircraft will taxi over to the runway from the "hot pad" staging area at Vandenberg Air Force Base where the Pegasus rocket was mated to the L-1011's underside.
Takeoff time is scheduled for 1304 GMT (8:04 a.m. EST; 5:04 a.m. local) to begin the 58-minute flight out to the launch point off the California coast.
TUESDAY, MARCH 14, 2006
NASA will put three micro-sats into orbit to test miniaturized technologies and techniques for operating constellations of science probes. The Space Technology 5 mission will last three months.
The ST5 craft will be blasted into space by the air-launched Pegasus XL rocket made by Orbital Sciences. A modified L-1011 carrier aircraft, called the Stargazer, hauls the three-stage booster off the California coast from Vandenberg Air Force Base where the winged rocket will drop at approximately 1402 GMT (9:02 a.m. EST; 6:02 a.m. local).
With the push of a button in the Stargazer's cockpit, the Pegasus rocket is cast free to fall for five seconds, dropping 300 feet below the aircraft. During the plunge, the onboard flight computer will sense the rocket's separation from the carrier jet and issue a command to release the safety inhibits in preparation for ignition.
The first stage solid-fueled motor of Pegasus is lit at T+5 seconds to begin the powered journey to orbit for the $130 million ST5 mission.
At T+1 minute, 17 seconds, the Orion 50S XL first stage motor consumes all of its solid-fuel propellant and burns out at an altitude of 34 miles. A short ballistic coast period begins before the spent first stage is separated to fall into the Pacific Ocean.
The Pegasus rocket's Orion 50 XL second stage begins firing at T+1 minute, 31 seconds to continue the trip to orbit. During the firing, at T+2 minutes, 11 seconds, the payload fairing that protected the micro-sats during atmospheric ascent is jettisoned 71 miles above Earth.
Having consumed its supply of solid-fuel propellant, the second stage motor burns out at T+2 minutes, 44 seconds. The rocket will coast for a couple of minutes before releasing the spent stage.
The solid-fueled Orion 38 third stage ignites at T+plus 5 minutes, 3 seconds about 176 miles high to deliver the ST5 spacecraft into the desired elliptical orbit around Earth. That orbit of 186 by 2,796 miles, inclined 105.6 degrees to the equator, is achieved with cutoff of the third stage at T+6 minutes, 11 seconds.
Release of the 55-pound micro-sats from the launcher occurs one by one from a special rack that supported them during the ride to space. The forward-most craft jettisons at T+plus 9 minutes, 31 seconds; the middle at T+plus 12 minutes, 41 seconds; and the aft-most at T+plus 15 minutes, 51 seconds to complete the Pegasus rocket's 37th launch since debuting in 1990.
1748 GMT (12:48 p.m. EST)
NASA spokesman George Diller says there are no technical issues being addressed. The rocket and the Space Technology 5 micro-sats are ready to fly.
MONDAY, MARCH 13, 2006
The Space Technology 5 launch has been rescheduled for Wednesday during a window extending from 1357-1519 GMT (8:57 to 10:19 a.m. EST; 5:57 to 7:19 a.m. local time).
An air-launched Pegasus rocket made by Orbital Sciences will haul the three birthday-cake-size spacecraft into a highly elliptical orbit and then deploy them for a 90-day mission. The 55-pound micro-sats will probe Earth's magnetic field using highly sensitive magnetometers to demonstrate whether such tiny craft can do the job.
"The future of space science is dependent upon the continual development of new and ever more powerful space-borne technologies," said Jim Slavin, ST5 project scientist. "The lessons learned from the development and flight of ST5's three full-service micro-spacecraft constitute a major step toward the use of 'constellations' or 'swarms' of small spacecraft to accomplish science that cannot be done with a single spacecraft, no matter how capable."
The Pegasus rocket is mounted to the belly of Orbital's L-1011 carrier aircraft at Vandenberg Air Force Base, California. The jet will carry the rocket over the Pacific Ocean and release it for the launch into space. Wednesday's targeted "drop time" to launch the rocket is 1402 GMT (9:02 a.m. EST; 6:02 a.m. local).
The bleak weather outlook for Tuesday -- an 80 percent chance of violating the launch rules due to clouds, rain and lightning -- prompted mission managers to forego a countdown, which would have commenced at 1:30 a.m. local time.
And the forecast for Wednesday is the complete opposite. Air Force meteorologists predict an 80 percent chance of favorable weather.
Officials didn't want the ground crews working overnight if there was little hope of launching Tuesday. That, coupled with the good weather on Wednesday, led to the decision to postpone the mission 24 hours, NASA spokesman George Diller said.
Watch this page for a complete launch preview later today.