ULA - Atlas V 401 - TDRS-L

Screenshot from ULA Webcast of the TDRS-L launch. Another late night launch just waiting for GO

Mission Rundown: ULA - Atlas V 401 - TDRS-L

Written: February 2, 2023 

Lift Off Time	January 23, 2014 – 21:33:00 EST January 24, 2014 – 02:33:00 UTC
Mission Name	TDRS-L
Launch Provider	ULA - United Launch Alliance
Customer	NASA
Rocket	Atlas V 401
Launch Location	Space Launch Complex 41 - SLC-41 Cape Canaveral Air Force Station, Florida
Payload	BSS-601 Tracking and Data Relay Satellite
Payload mass	3 540 kg ~ 7 615 pounds
Where did the satellite go?	Geostationary Transfer Orbit Initial orbit - 4 839 km x 35 788 km x 25,46°
Type of launch system?	Atlas Evolved Expendable Launch Vehicle - No SRB
The first stage landing zone?	Bottom of the Atlantic Ocean 2 500 km downrange
Type of second stage?	Centaur RL-10A-4-2 engine - 14m 58s burn time
Is the 2nd stage derelict?	Yes - Main engine 3rd start/cutoff wasn’t evident Last known orbit is 3 603 km x 33 651 km x 23.6°
Type of fairing?	4.2 meter two part metallic fairing
This will be the:	– 78th flight of all ULA rockets – 43rd flight of an Atlas V rocket - Tail no. AV-043 – 17th ULA mission for NASA – 1st mission for ULA in 2014
Where to watch Where to read more in detail	NASA/ULA YouTube link provided by Zachary Taylor Want to know or learn more go visit or see Tim Dodd

Launch debriefing (This did happen) Two Mach One rings are visible at 06:33 Contrail are visible and formed at MaxQ Centaur acceleration increase from 26.5 to 39.8 feet per square second as propellant gets burned away The telemetry change when Centaur reach orbital velocity MECO-1 happens at T+1104 seconds

L-00:05:07 Host: T-00:04:00 T 00:00:00 T+00:01:26 T+00:01:31 T+00:04:03 T+00:04:08 T+00:04:19 T+00:04:28 T+00:18:24 T+00:20:09 T+01:40:08 T+01:45:57 T+02:09:27 T+02:19:27

NASA/ULA live feed at 04:37 George Diller, Marty Malinowski Release -4 minute hold at 01:07 Liftoff at 05:07 - No T+ clock - 02:33:00 UTC Mach 1 at 06:33 - Speed Mach One 1225,5 km/h MaxQ at 06:38 - Maximum aerodynamic pressure BECO at 09:10 - Atlas V booster is empty - 243 second Stage separation at 09:15 - Just losing 95% weight MES-1 at 09:26 - Centaur RL-10A-4-2 engine start - 834s Fairing separation at 09:35 - Computer graphics delayed MECO-1 at 23:31 - Direct orbit transfer burn complete Wrap up from ULA at 25:23 - Calculated T+ - Audio only MES-2 to SECO-2 doing a 63 second orbit expansion burn NASA/ULA doesn’t show deployment of TDRS-L Centaur blowout of remaining gasses and fuel Centaur 2nd stage becomes derelict space debris

Atlas V 401 MAVEN	Atlas V 501 NROL-39	Atlas V 401 TDRS-L	Delta IV M+4,2 GPS IIF-5	Atlas V 401 DMSP 5D3 F-19
Atlas V 541 NROL-67	Delta IV M+4,2 GPS IIF-6	Atlas V 401 NROL-33	Delta II 7320-10 OCO-2	Delta IV M+4,2 AFSPC-4

Covering all bases in space

United Launch Alliance successfully conducted their first mission of 2014 by launching an Atlas V 401 rocket on Thursday evening January 23, thus deploying NASA’s latest Tracking and Data Relay Satellite, TDRS-L.

Liftoff from Cape Canaveral Air Force Base Space Launch Complex 41 occurred at 21:33 EST local time - equivalent to 02:33 UTC on Friday.

Flight path of TDRS-L from SLC-41. With one long burn Centaur is in geostationary transfer orbit

The TDRS-L payload

The twelfth spacecraft in NASA’s Tracking and Data Relay Satellite System (TDRSS), TDRS-L is the second of the three third-generation satellites.

TDRS-L is a 3,454 kilogram (7,615 lb) satellite which was manufactured by Boeing and is based around the BSS-601 satellite bus.

TDRS-L has a design life of 15 years, however most TDRS satellites have significantly exceeded their design expectations. The satellite carries an R-4D-11-300 apogee motor to raise itself into its final orbit and carry out other maneuvers.

TDRS-L is powered by solar panels, generating between 2.8 and 3.2 kilowatts of power depending on illumination.

The satellite carries s-band phased array antenna to allow simultaneous communications with five other spacecraft, as well as two steerable antennas providing S, Ku or Ka band coverage to spacecraft requiring communications at a higher data rate.

TDRS satellites are used by NASA to provide communications links between spacecraft in orbit – including the International Space Station and Hubble Space Telescope – and ground controllers. Part of NASA’s Space Network, TDRSS was implemented to reduce NASA’s dependence on ground stations and airborne tracking assets.

Use of the network is not restricted to NASA missions; amongst other users United Launch Alliance and Sea Launch both use TDRS to relay data from their rockets during launch, JAXA and the European Space Agency have used TDRS for missions, including HTV and ATV flights to the ISS, and the system is rumored to be used by NRO - the National Reconnaissance Office to supplement its own Satellite Data System, transmitting data from reconnaissance satellites for analysis.

Older satellites in more highly-inclined orbits have been used to relay communications to the Amundsen–Scott Station at the South Pole; a site not usually accessible to communications satellites due to its extreme latitude.

The Atlas V 401 launch

The launch of AV-043, which marked the forty-third flight of an Atlas V, began with the ignition of the RD-180 engine at T-2.7 seconds. Its thrust exceeded the mass of the rocket about 1.1 seconds after T-0, allowing the vehicle to rise off the pad and begin its ascent.

Climbing vertically for 16.4 seconds, AV-043 cleared the pad before it began a series of roll, pitch and yaw maneuvers to place it onto the planned trajectory to achieve geosynchronous transfer orbit.

The rocket flew downrange on a heading of 101.4 degrees, passing through the area of maximum dynamic pressure, or Max-Q, 91.3 seconds after liftoff.

Booster Engine Cutoff, or BECO, marked the end of first stage flight, occurring four minutes and 1.9 seconds into the mission, with the Common Core Booster separating six seconds later.

After staging, the Centaur’s RL10 engine began its pre-start sequence; with ignition occurring ten seconds after the spent stage had been jettisoned. Ignition of the Centaur, or Main Engine Start 1 (MES-1), began the first of two planned burns for the upper stage during Thursday’s mission.

The first Centaur burn lasted 13 minutes and 55.1 seconds, with separation of the payload fairing from the nose of the rocket occurring eight seconds after ignition. At the end of the burn, a lengthy coast phase began.

The coast phase lasted an hour, twenty one minutes and 54.7 seconds, before the RL10 ignited again for its second burn. This raised the perigee of the orbit, reducing the amount of fuel TDRS-L must expend to reach its final destination.

By using less fuel at this phase of the mission, TDRS-L will have more available for maneuvering and stationkeeping, potentially allowing it a longer operational mission.

The second burn lasted 63.1 seconds. Four minutes and 46 seconds after it ended, TDRS-L was separated from the Centaur to begin its own mission. The target orbit for spacecraft separation is a 4,839 by 35,788 kilometers (3007 by 22,238 mi; 2613 by 19,324 nmi) inclined at 25.5 degrees to the equator, with an argument of perigee of 180 degrees.

The Atlas V 401 rocket

The rocket which deployed TDRS-L was an Atlas V 401, tail number AV-043. The smallest Atlas V configuration, the 401 variant consists of a single Common Core Booster (CCB) first stage, and a Single-Engine Centaur (SEC) upper stage.

The Common Core Booster is powered by a single RD-180 engine, derived from the RD-170 developed by the Soviet Union to power its Zenit rocket and the Centaur is powered by an RL10A-4-2 engine. The 4.2 meters (13 feet) payload fairing will encapsulate TDRS-L.

The Atlas V 401 rocket, tail no. AV-043 is standing 57.31 meters - 188 feet tall on SLC-41.

Atlas V 401 split in its major parts. This is a generic non mission specific graphic configuration

Facts on the Atlas V 401 launch vehicle

Height of Atlas V 401: 188 feet (57.31 meters)

Mass at liftoff: 336,582 kilograms - 740,480 pounds

Thrust at liftoff: 3.8 mega-Newtons - 0.86 million lbf

Fuel onboard: 91,000 gallons of liquid propellant

LOX+LH2 = 66,000 gallon of cryogenic liquid propellant in three tanks

NasaSpaceFlight: William Graham link Gunter’s Space Page: Details Atlas link

Coauthor/Text Retriever Johnny Nielsen link to ULA launch list - Link to ULA Fan

ULA - Atlas V 501 - NROL-39

Screenshot from ULA Webcast of the NROL-39 launch. Standing here in the spotlight feeling lonely

Mission Rundown: ULA - Atlas V 501 - NROL-39

Written: February 6, 2023 

Lift Off Time	December 5, 2013 – 23:14:30 PST December 6, 2013 – 07:14:30 UTC
Mission Name	NROL-39
Launch Provider	ULA - United Launch Alliance
Customer	NRO - National Reconnaissance Office
Rocket	Atlas V 501
Launch Location	Space Launch Complex 3E - SLC-3E Vandenberg Air Force Base, California
Payload	Topaz-3 Radar Reconnaissance Satellite - USA-247 GEMSat - ELaNa II with 12 CubeSats
Payload mass	6 420 kg ~ 14 154 pounds - Max. mass capacity
Where did the satellites go?	Retrograde Polar Orbit - 1 069 km x 1 091 km x 122,99° Retrograde Polar Orbit - 467 km x 883 km x 120,01°
Type of launch system?	Atlas Evolved Expendable Launch Vehicle No SRB
The first stage landing zone?	Bottom of the Pacific Ocean 2 500 km downrange
Type of second stage?	Centaur RL-10A-4-2 engine - 14m 50s burn time
Is the 2nd stage derelict?	Yes - Main engine 4th start/cutoff wasn’t evident Graveyard orbit is 488 km x 890 km x 120.45°
Type of fairing?	5.4 meter two part carbon composite fairing
This will be the:	– 77th flight of all ULA rockets – 42th flight of an Atlas V rocket - Tail no. AV-042 – 16th ULA mission for NRO – 11th mission for ULA in 2013
Where to watch Where to read more in detail	ULA YouTube link provided by Matthew Travis Want to know or learn more go visit or see Tim Dodd

Launch debriefing (This did happen) Sound is very low and choppy at best - some launch details are not heard clearly All time stamps after wrap up is guesses and marked with an end on 27 seconds

L-00:20:28 Host: L-00:07:00 T-00:04:00 T 00:00:00 T+00:01:24 T+00:01:32 T+00:03:38 T+00:04:29 T+00:04:24 T+00:04:29 T+00:04:39 T+00:14:27 T+00:18:27 T+00:21:27 T+00:42:27 T+02:52:30 T+03:32:30 T+03:49:27 T+03:59:27

ULA live feed at 04:37 Matt Donovan, Marty Malinowski Final Polling preparing the launch at 13:28 Release -4 minute hold at 16:28 Liftoff at 20:28 - No T+ clock - 07:14:30 UTC Mach 1 at 21:52 - Speed Mach One 1225,5 km/h MaxQ at 22:00 - Maximum aerodynamic pressure Fairing separation at 24:06 - Seen from ground camera Wrap up from ULA at 25:57 - Calculated T+ BECO at 25:39 - Atlas V booster is empty - 264 second Stage separation at 25:42 - Just losing 95% weight MES-1 at 25:52 - Centaur RL-10A-4-2 engine start MECO-1 at 53:14 - Coasting toward Antarctica ice shelf MES-2 to SECO-2 doing a 29 second insertion burn ULA doesn’t show deployment of NROL-39 MES-3 - SECO-3 in a 29 second deorbit burn to LEO Deployment start of CubeSats scheduled at 10:06 UTC Deployment of CubeSats ends at 10:46 UTC DCSS Centaur blowout of remaining gasses and fuel DCSS Centaur 2nd stage becomes derelict space debris

Atlas V 401 MAVEN	Atlas V 501 NROL-39	Atlas V 401 TDRS-L	Delta IV M+4,2 GPS IIF-5	Atlas V 401 DMSP 5D3 F-19
Atlas V 541 NROL-67	Delta IV M+4,2 GPS IIF-6	Atlas V 401 NROL-33	Delta II 7320-10 OCO-2	Delta IV M+4,2 AFSPC-4

Will you bring the ‘kids’ with you?

The United Launch Alliance (ULA) have launched their Atlas V rocket on the NROL-39 mission for the National Reconnaissance Office. Liftoff from Vandenberg Air Force Base in California on December 5, 2013 was on schedule at the opening of its launch window at 23:13 Pacific standard time Thursday (07:13 UTC on Friday).

NOTAM of NROL-39 flight path shows it’s flying southeast from Vandenberg heading for a very retrograde orbit. Debris fields are marked for impact from fairing parts and the core booster

The primary payload for Thursday’s launch was a classified payload for the National Reconnaissance Office, NROL-39, whose launch was contracted in 2003 as part of the second block-purchase of Evolved Expendable Launch Vehicle (EELV) launches; Buy 2.

The Atlas V rocket was also carrying the Government Experimental Multi-Satellite payload, or GEMSat; a Naval Postgraduate School CubeSat Launcher (NPSCUL) which will deploy twelve nanosatellites.

Like most of the NRO’s satellites, the NROL-39 spacecraft and its mission are classified; however due to the nature of satellite programs it is hard to keep many details secret.

The NROL-39 payload

Notices to Airmen, or NOTAMS, issued for the L-39 launch showed that the rocket will follow the same trajectory used for the NROL-41 launch – leaving the satellite in an orbit only typically used for the NRO’s radar imaging satellites.

Because of this, it can be inferred that NROL-39 is the third satellite in the NRO’s current-generation radar reconnaissance fleet. It follows the Atlas V 501 launch of the NROL-41 mission, or USA-215, launched in September 2010, and NROL-25 (USA-234) which was launched by a Delta IV in April 2012.

The radar imaging program is believed to be a remnant of the NRO’s Future Imagery Architecture (FIA) program, which was intended to produce new-generation optical and radar-imaging surveillance satellites, replacing the earlier KH-11 and Onyx radar imaging spacecraft.

NROL-39 is the third mission to launch out of the four in the 2002 document, following NROL-25 and NROL-41 which were also Topaz satellites.

The last spacecraft of the group, NROL-45, is also slated to use an Atlas V 501 flying from Vandenberg, and as such is almost certain to be a fourth Topaz satellite.

Topaz launches have so far used a single inclination – 123 degrees – which corresponds to a retrograde analogue of the 57 degree plane. The two operational Topaz satellites’ orbits are separated by 180 degrees in terms of the longitude of their ascending nodes, with NROL-39’s launch window suggesting that its orbital plane will be halfway between them. Their orbits cross the Equator from south on opposite sides of the Earth.

GEMSat, which shared NROL-39’s journey into orbit, marks the second time excess capacity on an NRO launch has been used to carry CubeSats – the first being OUTSat which was carried aboard the NROL-36 mission last year.

Both OUTSat and GEMSat are Naval Postgraduate School CubeSat Launchers (NPSCULs), which consist of eight Poly Picosatellite Orbital Deployers (PPODs) each with capacity equivalent to three single-unit CubeSats.

The NROL-39 payload consists of twelve CubeSats, seven for the US military and five for various educational institutions. The educational satellites were flown as part of NASA’s Educational Launch of Nanosatellites (ELaNa) program and are designated ELaNa II.

ELaNa II is a NASA program to provide launch opportunities for educational CubeSat missions. Consisting of two 3U PPODs, ELaNa II was a revived ‘canceled’ launch number of the program started in 2011. The most recent mission was ELaNa IV, launched as part of the ORS-3 mission aboard a Minotaur I rocket last month.

Therefore the current ELaNa batch isn't ELaNa ‘five’ that’s catching a ride with NROL-39.

The Atlas V 501 launch

The specifics of AV-042 Belle’s launch profile are classified, however the mission began, like all Atlas V flights, with ignition of the ‘russian derived’ RD-180 engine 2.7 seconds in advance of the planned T-0.

At approximately T+1.1 seconds Belle lifted off from the pad, beginning her ascent into orbit. The vehicle rolled to the proper launch azimuth, flying southwest out over the Pacific. Pitch and yaw maneuvers were then used to attain the proper attitude for the journey to low Earth orbit. The rocket's azimuth is equivalent to its compass heading.

The flight computer onboard AV-042 switched to closed-loop control around 50 seconds after launch, shortly afterwards completing its roll sequence.

Approximately 146 seconds into the flight AV-042 Belle passed through Mach 1, followed shortly by the area of maximum dynamic pressure, or max-Q.

In preparation for payload fairing separation, the RD-180 was throttled down at 175 seconds into the flight. Fairing separation occurred a little over 40 seconds later.

The forward load reactor, a device used to keep the fairing rigid which attaches near the front of the Centaur, was jettisoned five or six seconds after the fairing.

Fairing separation must occur before staging since the Centaur is encapsulated. Depletion of the first stage occurred about four minutes and 20 seconds after liftoff, with the spent stage separating six seconds later.

Ten seconds after first stage separation, the Centaur’s RL10A-4-2 engine was scheduled to ignite for its first burn.

The Centaur will either make a long burn followed by a short burn, or one longer burn, prior to the separation of the primary payload.

Based on its launch azimuth and previous Topaz launches, amateur observers expect to find NROL-39’s payload in a 1,067 by 1,080 kilometer (663 by 671 statute miles, 576 by 583 nautical miles) orbit with 123 degrees inclination and an orbital period of approximately 106.7 minutes.

The Firebird satellites are expected to be placed into a 465 by 972 kilometer elliptical orbit (289 by 604 miles, 251 by 525 nautical miles) at the same inclination; the Centaur is likely to make an additional burn after spacecraft separation to attain this, rather than dropping the satellites off in a parking orbit.

All of the CubeSats will be deployed in the same orbit. Since no NOTAMS have been issued from FAA as evidence for the Centaur to be deorbited, it will presumably remain in orbit after CubeSat separation, in a similar orbit to the CubeSats.

The NRO’s use of retrograde orbits for its Topaz radar satellites is believed to improve the performance of the imaging payload, due to the increased velocity of the satellite relative to the surface of the Earth. The doppler shift in the radar return signal becomes stronger.

The Atlas V 501 rocket

The NROL-39 mission made use of United Launch Alliance’s Atlas V rocket. Named Belle, and with the tail number AV-042, the Atlas flew in the 501 configuration with a five-meter RUAG payload fairing, no solid rocket motors and a single-engine Centaur upper stage.

AV-042 stands 196 feet tall. Weighs 76000 pounds empty and 750000 pounds fueled.

AV-042 was the forty-second Atlas V to fly, and the fifth to use the 501 configuration. In addition to NROL-41, previous Atlas V 501 launches have deployed the three flights of the X-37B spacecraft, the most recent of which is still in orbit having launched last December.

The first stage of the Atlas rocket is a Common Core Booster (CCB), which is fuelled with RP-1 propellant oxidized by liquid oxygen. Its RD-180 engine was developed by NPO Energomash of Russia, and is derived from the RD-170 series developed for the Russian or rather Soviet Zenit and Energia program.

The ‘engine’ consists of one cryogenic propellant turbopump, that feeds propellant to two burn chambers with two engine bells - nozzles - below them, capable of producing up to 4.15 meganewtons (930,000 pounds-force) of thrust.

The second stage, a single-engine Centaur (SEC), is mounted atop the first stage and encapsulated within the rocket’s payload fairing along with the payload. AV-042 is using a medium-length five meter fairing, developed by RUAG of Switzerland, with a diameter of 5.4 meters (17.7 feet) and a length of 23.4 meters (77 feet).

The Centaur is powered by one RL10A-4-2 engine burning liquid hydrogen and liquid oxygen. While the Atlas V is designed to use single or dual-engine Centaur stages, only the single-engine variant has been flown.

A dual-engine Centaur is currently under development to support commercial manned spaceflight missions, such as the Dream Chaser and Boeing’s CST-100 capsule.

The Atlas V launch complex at Vandenberg Air Force Base is Space Launch Complex 3E. That was converted from launching Atlas II to accommodate the Atlas V, a process which included increasing the height of the pad’s mobile service tower.

The first Atlas V launch from Vandenberg occurred in March 2008, with the USA-200 (NROL-28) satellite, and AV-042 is the seventh Atlas V vehicle to use the pad.

NasaSpaceFlight: William Graham link Gunter’s Space Page: Details Atlas link

Coauthor/Text Retriever Johnny Nielsen link to ULA launch list - Link to ULA Fan