Weather looks good for final shuttle landing

Editor's note...
  • Posted at 03:39 PM EDT, 07/20/11: Weather looks good for final shuttle landing
  • Updated at 05:00 PM EDT, 07/20/11: Adding Ferguson sign off for final night in space
CBS News

KENNEDY SPACE CENTER, FL--With forecasters predicting near ideal weather, entry Flight Director Tony Ceccacci said Wednesday he's optimistic about bringing the shuttle Atlantis back to a pre-dawn landing in Florida Thursday to close out NASA's 135th and final shuttle mission.

"We have a really, really good shot to come home tomorrow morning," he said during a pre-entry news briefing. "Of course, you've heard me say this, no matter what the forecast (is) at KSC, it's always 50-50. So when we come in on console tomorrow, we'll go ahead and see what the weather guys have for us and work it accordingly."

Entry Flight Director Tony Ceccacci outlines his strategy for bringing the shuttle Atlantis back to Earth Thursday. (Credit: NASA)
Atlantis commander Christopher Ferguson and pilot Douglas "Chunky" Hurley plan to fire the shuttle's twin braking rockets for three minutes and 17 seconds starting at 4:49:04 a.m. EDT (GMT-4), slowing the ship by about 223 miles per hour and putting the crew on course for a landing on runway 15 at the Kennedy Space Center at 5:56:58 a.m. A second landing opportunity is available one orbit later, at 7:32:55 a.m.

Astronaut Megan McArthur wished the crew good night at 1:29 p.m. Wednesday, telling Ferguson "your professionalism and excellence have been the best kind of tribute to the space shuttle and the many people who are part of its history. So we'll bid you good night, safe travels and we'll see you back in Houston for the celebration."

"Well, Megan, thank you, that was really very kind of you," Ferguson replied. "You know, 42 years ago today, Neil Armstrong walked on the moon. I consider myself fortunate that I was there to actually remember the event. I think there are probably a lot of folks in (mission control) who didn't have that privilege or honor, and I can only hope that day will come for them, someday.

"It's kind of interesting to be here on the final night of (this) shuttle mission. We don't quite know what to think, we're just trying to take it all in. I saw a quote (from Apollo 11 Flight Director Gene Kranz) that I thought was really good, and is very appropriate on this, the 42nd anniversary of the United States' presence on the moon. And that is, 'I pray that our nation will someday find the courage to accept the risk and challenges to finish the work that we started.' I bid a farewell to the Orbit 2 (flight control) team. ... When you go  out the door, like I said to Orbit 1, take a look back at the mission control room and make a memory. Good night from Atlantis."

The crew's first landing opportunity Thursday comes in darkness, 42 minutes before sunrise, while the second is in daylight. Despite the optimistic forecast and the desire among many for a daylight landing to better savor the shuttle's last homecoming, Ceccacci said he would not wave off one orbit just to improve visibility.

"Sitting at the entry flight director's console, there's a lot of things you have to worry about," he said. "You step back and look at this, and as nice as it would be to land in the daytime to get some very good pictures, you never want to give up an opportunity.

"You've all seen the KSC weather get worse, even though the forecast says hey, it's going to be clear and no wind. So when you're sitting at that console and you have the opportunity to come home, you take it, day or night. I know a lot of folks want to see this, but again, when you have that opportunity and it all looks good and it's safe to come home, you do it."

NASA will not be staffing its backup landing site at Edwards Air Force Base, Calif., on Thursday. If the weather or some other problem prevents a landing in Florida, the crew will remain in orbit an additional 24 hours and land Friday, on one coast or the other. The forecast both days for Florida and California calls for "go" conditions.

"Right now, our entry strategy for tomorrow is we're just going to try KSC only, just because the weather's looking very (good) there," Ceccacci said. "And if for some reason we can't make it home tomorrow, Friday will be our pick 'em day. That is, we'll just take a look at the KSC weather, Edwards weather and possibly Northrup (N.M.) weather, see how that looks, and we'll for sure come home on Friday."

Asked about his emotions on the eve of NASA's final shuttle entry -- and his last shift as a shuttle flight director -- Ceccacci said simply, "all good things must come to an end."

"For me, it's been an unbelievable journey on a magnificent flying machine," he said. "I'm very proud to have been part of the shuttle team. I've been blessed to have supported STS-1 as a flight controller, and have the honor to be the entry fight director for STS-135. So you can see I've ben here for a while.

"My congratulations and thanks go to all the thousands of dedicated and passionate team members who have made the shuttle program the success it has been, and contributed to the legacy it leaves behind. It's because of their blood, sweat and tears that we can say 'mission complete.' It's time to celebrate this amazing accomplishment and look forward to the future. Godspeed to all."

Then, in an aside to reporters, he added "you guys must know that we do have a motto in the mission control center, that flight controllers don't cry. So we're going to make sure we keep to that."

Here is a timeline for both landing opportunities (in EDT; best viewed with fixed-width font):
(Source: NASA)

Orbit 200 descent to KSC (07/21/11)
Deorbit burn duration: 3:17
Deorbit change in velocity: 223 mph


12:49 AM......Begin deorbit timeline
01:04 AM......Radiator stow
01:14 AM......Astronaut seat installation
01:20 AM......Computers set for deorbit prep
01:24 AM......Hydraulic system configuration
01:49 AM......Flash evaporator cooling system checks
01:55 AM......Final payload deactivation
02:09 AM......Payload bay doors closed
02:19 AM......Mission control 'go' for OPS-3 software load
02:29 AM......OPS-3 transition
02:54 AM......Entry switchlist verification
03:04 AM......Deorbit maneuver update
03:09 AM......Crew entry review
03:24 AM......Commander, pilot don entry suits
03:41 AM......Inertial measurement unit alignment
03:49 AM......Commander, pilot strap in; mission specialists don suits
04:06 AM......Shuttle steering check
04:09 AM......Hydraulic system prestart
04:16 AM......Toilet deactivation
04:29 AM......Mission control 'go' for deorbit burn
04:35 AM......Mission specialists seat ingress
04:44 AM......Single APU start

04:49:04 AM...Deorbit ignition (altitude: 239.8 miles; dT: 3:17; dV: 223 mph)
04:52:21 AM...Deorbit burn complete

05:24:50 AM...Atmospheric entry (altitude: 75.7 miles; velocity: mach 25)
05:29:45 AM...1st roll command to left
05:41:13 AM...1st roll left to right
05:43:58 AM...C-band radar acquisition
05:50:12 AM...Velocity less than mach 2.5 (altitude: 83,600 feet)
05:52:22 AM...Velocity less than mach 1 (altitude: 47,000 feet0
05:53:11 AM...Start left turn to runway 15 (altitude: 35,300 feet)
05:56:58 AM...Landing

(Source: NASA)

Orbit 201 descent to KSC (07/21/11)

06:05 AM......Mission control 'go' for deorbit burn
06:11 AM......Mission specialists seat ingress
06:20 AM......Single APU start

06:25:44 AM...Deorbit ignition (altitude: 240.7 miles)
06:29:01 AM...Deorbit burn complete

07:00:44 AM...Atmospheric entry (altitude: 75.7 miles)
07:05:38 AM...1st roll command to left
07:17:57 AM...1st left to right roll reversal
07:19:55 AM...C-band radar acquisition
07:26:05 AM...Velocity less than mach 2.5 (altitude: 84,100 feet)
07:28:16 AM...Velocity less than mach 1 (altitude: 46,800 feet)
07:28:46 AM...Start left turn to runway 15 (altitude: 39,200 feet)
07:32:55 AM...Landing