AEHF 1 (Atlas 5 launched on Aug 14th, 2010)

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Launch window: 11:07-13:06 GMT (7:07-9:06 am EDT)
Launch site: SLC-41, Cape Canaveral Air Force Station, Florida

The United Launch Alliance Atlas 5 (AV-019) rocket will launch the first Advanced Extremely High Frequency (AEHF) satellite. Built by Lockheed Martin, this U.S. military spacecraft will provide highly-secure communications. The rocket will fly in the 531 vehicle configuration with a five-meter fairing, three solid rocket boosters and a single-engine Centaur upper stage. Delayed from July 2009.

United Launch Alliance's Launch Information Page:
AEHF Wikipedia Article: ... _Frequency
Spaceflight Now's Article:
Lockheed Martin's AEHF Page: ... index.html
Lockheed Martin's AEHF Animation: ... _DISC2.mp4
Lockheed Martin's AEHF Overview Video: ... _DISC1.mp4
Lockheed Martin's AEHF Fact Sheet:


Atlas 531 Launch Vehicle

Atlas 5 Wikipedia Article:
ULA's Atlas V Page: ... lasV.shtml
ULA's Atlas V Product Card: ... t_card.pdf
ULA's Atlas V User Guide: ... de2010.pdf
Astronautix Atlas V Page:
Atlas V at Günter's Space Pages: ... -5-531.htm
Spaceflight Now's Atlas V Article: ... ocket.html


Atlas 5 First Stage:

One Atlas 5 common core booster (CBC) having one RD-180 engine burning RP-1/LOX.

RD-180 Wikipedia Article:
NPO Energomars RD-180 Page:
Purdue University RD-180 Page: ... ids/rd180/



Atlas 5 Boosters:

Atlas 531 has 3 Aerojet solid rocket boosters.

Aerojet Wikipedia Article:
Aerojet Space Lift Propulsion Pages:


Atlas 5 Second Stage:

Single engine (RL-10A) Centaur rocket stage burning LH[sub]2[/sub]/LOX.

Centaur Wikipedia Article:
NASA's Centaur History Page: ... ntaur.html
P&W Rocketdyne RL-10 Page: ... tdyne/RL10
RL-10 Fact Sheet: ... r_RL10.pdf
NASA's RL-10 History Page:
Historic photo from NASA's gallery: ... _1685.html


Cape Canaveral Air Force Station

Cape Canaveral Air Force Station Wikipedia Article: ... ce_Station
Patrick Air Force Base Official Site:
SLC-41 Wikipedia Article: ... Complex_41
Astronautix LC41 Page:
Google Maps: ... 57,-80.583




Re: Aug 12, Atlas 5 - AEHF 1

I have updated launch time. However there are two dates depending on the web site... Spaceflightnow says Aug 12, but ULA Launch Aug 10. ULA's own page can be out of date and so can be Spaceflightnow. Personally I bet Spaceflightnow's information is correct, but somebody who knows, please share your information. At the moment I don't have enought time to study this further.


Re: Aug 12, Atlas 5 - AEHF 1 : Mission Status Center
By Justin Ray

Welcome to Spaceflight Now's live coverage of the Atlas 5 rocket launching the U.S. military's first Advanced Extremely High Frequency communications satellite.
1055 GMT (6:55 a.m. EDT)
With daybreak lighting the way, the Atlas 5 rocket is emerging from its vehicle assembly building for the journey to the launch pad.

Riding atop a mobile launching platform, the 197-foot-tall space booster is moving to Cape Canaveral's Complex 41 for this critical flight to deploy the first Advanced Extremely High Frequency (AEHF) spacecraft.
1048 GMT (6:48 a.m. EDT)
The rocket's rollout to the pad has begun.
An Atlas 5 rocket launching the inaugural craft in the U.S. military's new series of secure communications satellites will be rolled the pad in the morning for Saturday's planned liftoff.

The slow half-hour drive from the 30-story Vertical Integration Facility to Cape Canaveral's Complex 41 pad uses a pair of specially-made "trackmobiles" to carry the rocket's 1.4-million pound mobile launching platform along rail tracks for the 1,800-foot trip.

The two-stage rocket sporting three strap-on solid boosters was put together inside the assembly building this summer. The Advanced Extremely High Frequency (AEHF) spacecraft payload was mounted atop the vehicle last week.

The Atlas 5 is designed to spend minimal time at the launch pad, which does not include a service gantry like other rockets.

Saturday's launch window extends from 7:07 to 9:06 a.m. EDT (1107-1306 GMT).

Weather forecasters are predicting an 80 percent chance of favorable conditions for the space shot.

The outlook includes scattered clouds, a small threat of an isolated shower or thunderstorm, good visibility, westerly winds of 10-14 knots and a temperature around 81 degrees F.

Meteorologists say the only worry will be cumulus clouds associated with a stray rain shower. : First AEHF satellite readied for launch
This collection of photographs shows the inaugural Advanced Extremely High Frequency satellite -- AHEF 1 -- being encapsulated within the Atlas 5 rocket's nose cone at the Astrotech processing cleanroom near Titusville and then delivered to the Vertical Integration Facility at Cape Canaveral's Complex 41 for mating atop the launch vehicle.


Photo credit: United Launch Alliance/Kevin O'Connell



Photo credit: United Launch Alliance/Tony Gray



Re: Aug 14, Atlas 5 - AEHF 1

AEHF delivery video:


Not yet official videos, but:





Re: Aug 14, Atlas 5 - AEHF 1 : United Launch Alliance Atlas V Successfully Launches First AEHF Mission
CAPE CANAVERAL AIR FORCE STATION, Fla., Aug. 14 /PRNewswire/ -- A United Launch Alliance Atlas V rocket successfully launched the Advanced Extremely High Frequency-1 (AEHF-1) satellite for the Air Force at 7:07 a.m. EDT today from Space Launch Complex- 41. The AEHF constellation of four satellites will provide 10 times greater capacity and channel data rates six times higher than that of the existing Milstar II communications satellites. AEHF-1 will be joined by the next two AEHF satellites to be launched during the next two years by ULA.


Re: Aug 14, Atlas 5 - AEHF 1




Re: Aug 14, Atlas 5 - AEHF 1

WOW quite a launch, thanks Zipi.

Andrew Brown.


Guest : Military satellite relying on backup plan to save itself

Posted: August 30, 2010

A rescue plan is being implemented to salvage the U.S. military's pricy new communications satellite despite a serious malfunction that knocked out its main engine and stymied the craft's maneuvering ability.


An artist's concept of AEHF 1. Credit: Northrop Grumman

The Advanced Extremely High Frequency 1 spacecraft was launched into a preliminary orbit by an Atlas 5 rocket on August 14 from Cape Canaveral, Florida.

The United Launch Alliance-built booster performed its job as designed and successfully deployed the 13,420-pound payload into a supersynchronous transfer orbit with a high point of 31,200 miles, low point of 140 miles and inclination of 22.2 degrees.

Plans called for the satellite to fire its 100-pound-thrust Liquid Apogee Engine three times over the course of several days to raise the orbit's low point to 11,800 miles and reduce the inclination to 6 degrees relative to the equator, achieving an intermediate orbit.

From that point forward, the craft's exotic electric propulsion system using Hall Current Thrusters would be fired almost continuously for weeks to finish shaping the orbit into a circular, geosynchronous altitude 22,300 miles high and inclined 4.8 degrees.

AEHF 1 was expected to reach its on-orbit testing location at 90 degrees West longitude over the equator within 105 days of liftoff.

But those plans were thwarted a day after launch during the initial orbit raising burn when the satellite's main engine shut down shortly after ignition for still-unexplained reasons. Another attempt tried August 17 also ended immediately when the engine again failed to generate the expected acceleration.


SDC Story

A propulsion system glitch aboard the U.S. Air Force's first Advanced Extremely High Frequency secure communications satellite has forced the service to devise a new orbit-raising plan utilizing smaller thrusters that will delay the craft's arrival at its operating orbit by six months to seven months, according to a service official.

The satellite's operational service life is not expected to be reduced as a result of the revised plan, said Dave Madden, director of the Air Force's Military Satellite Communications Systems Wing. ...

The Air Force Space and Missile Systems Center, Aerospace Corp., and AEHF prime contractor Lockheed Martin Space Systems developed a backup plan to use one of the satellite's other propulsion systems to get it to its proper orbit, albeit later than planned, Madden said. The satellite has another propulsion system that is fueled by the same tank as the liquid apogee engine but produces only one-twentieth of the thrust. Engineers believe this system can be used to boost the spacecraft to 19,000 kilometers at perigee in seven months to eight months, Madden said.

Operators began executing the plan Aug. 29, firing the smaller thrusters for 40 minutes and raising the satellite's perigee to 950 kilometers. It was essential to raise the satellite as quickly as possible because it was losing about 2.5 kilometers of altitude per day because of atmospheric drag and the spacecraft had already had to be maneuvered to dodge an oncoming piece of debris, Madden said.


Guest : First milestone reached on AEHF 1's long road to orbit

Posted: September 5, 2010

The U.S. Air Force has completed the initial phase of its multi-step, multi-month strategy to maneuver the new secure communications satellite into the proper orbit without the main engine operating.

United Launch Alliance's highlights film from liftoff

Satellite-tracking hobbyists report that the Advanced Extremely High Frequency 1 spacecraft has climbed into the intermediate orbit that project officials were targeting.

The craft spent the week performing four orbit raising burns using tiny steering thrusters to boost the low end of the satellite's highly elliptical orbit by more than 400 miles.

Controllers are employing the so-called Reaction Engine Assembly motors to save the satellite after its large Liquid Apogee Engine failed to work shortly after launch.

Air Force officials are confident AEHF 1 will achieve the intended geosynchronous orbit and have enough remaining fuel to function for its full 14-year mission. But getting the satellite boosted into the circular perch using thrusters instead of the main engine will take a half-year longer to accomplish.


Guest : Main engine probably not to blame for AEHF 1 trouble

Posted: October 19, 2010

As investigators narrow the list of potential culprits in the Advanced Extremely High Frequency satellite's main propulsion system problem, the Air Force has decided to delay launching the follow-up spacecraft and rearrange its upcoming Atlas rocket manifest.
"I will tell you that I have high confidence it was not the engine itself and that it was part of the propulsion system that we think we are going to end up looking closely at," said Dave Madden, Military Satellite Communications Systems Wing program director at the Air Force's Space and Missile Systems Center.

"I don't want to speculate on the answer because right now we're going through some red team reviews. But right now I feel very, very confident that the IHI engine that we use was not the cause of this issue," Madden said in an interview October 14.
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