Payload Might Be Upgraded To Fly on a Later Falcon Mission


The Pentagon has decided to cancel the launch of its experimental TacSat-1 satellite, which had been slated to lift off on the next flight of Space Exploration Technologies Corp.’s Falcon 1 rocket.

Musk, president of El Segundo, Calif.-based Space Exploration Technologies (SpaceX) told Space News Aug. 16 he had been informed that week by TacSat-1 program officials at the U.S. Naval Research Laboratory here about the decision to cancel the launch, which had been slated for this fall.

Musk said he was told by Tacsat-1 program manager Mike Hurley that the launch is being canceled because TacSat-2, which has been in orbit since December, already is demonstrating many of the capabilities TacSat-1 was built to showcase. TacSat-2 vaulted ahead of TacSat-1 in the launch queue due to delays associated with the Falcon-1 rocket.

“At first, there were issues with [TacSat-2] and it seemed like [TacSat-1] would still be needed,” Musk said. “Recently, however, the [TacSat-2] team was able to fix the problems and there is no longer any point to flying [TacSat-1] unless the payload is upgraded.”

Naval Research Laboratory spokesman Dick Thompson referred questions about TacSat-1 to the Pentagon’s Office of the Director of Defense Research and Engineering, or DDRE.

U.S. Air Force Lt. Col. James Griswold, a space strategist in DDRE’s Rapid Reaction Technology Office, confirmed in an Aug. 21 interview that TacSat-1’s launch had been canceled.

“TacSat-2 has shown that it can do the same things that TacSat-1 was going to do,” he said. “We don’t want to put a payload in space that doesn’t promise value to the warfighter in the field.”

Griswold said upgrading TacSat-1 and launching it under a different name is a possibility.

“One of the options that we’re looking at down the road in discussing with the [Operationally Responsive Space] office is maybe upgrading the payload of TacSat-1

… and then potentially fly that,” he said.

A Pentagon source who asked not to be identified expressed disappointment with the decision to cancel the TacSat-1 launch, and said it would be analogous to the United States not returning to the Moon after a successful initial landing.

The source said launching TacSat-1 would have given the military additional experience with operating a TacSat, and using two similar satellites at once would have allowed the military to explore concepts of operation for working with a small constellation.

The Pentagon spent about 12 months and $15 million building TacSat-1. Griswold said TacSat-1 originally was supposed to launch in 2004, but has been in storage since then waiting for SpaceX to finish Falcon 1 and demonstrate it was ready to carry the payload to orbit.

Falcon 1 has launched twice, failing to reach orbit on both occasions. The first launch, conducted in March 2006, ended shortly after liftoff due to an engine fire that was traced back to a corroded nut. Falcon 1’s second launch, conducted this past March, fared better. The rocket reached an altitude of 300 kilometers before a roll-control malfunction prevented it from completing its flight plan. A SpaceX-led launch review conducted with the Pentagon’s assistance concluded that Falcon 1’s problems were relatively minor and that the vehicle was ready to launch a satellite on its next flight.

Griswold could not quantify what the Pentagon would have to spend to go ahead with the TacSat-1 launch at this point, but he said that costs would include pulling the satellite out of storage,

retesting it and paying for a year of mission operations. TacSat-1 was to be operated by the Naval Research Laboratory from a facility in Blossom Point, Md.

Musk said he did not see the cancellation of the TacSat-1 launch as an indication the Pentagon lacks confidence in Falcon 1, though he predicted his rivals would see it as such.

“Those that wish us ill will claim that it is a lack of faith in our rocket, which is absolutely not true,” Musk said. “[TacSat-1] is going into storage, not onto another vehicle. And if the payload gets upgraded, it will almost certainly fly on a Falcon 1 in the future.”

Musk said while the Pentagon has pulled TacSat-1 from the flight manifest, it has not canceled its launch contract with


. The Pentagon is under contract to pay SpaceX about $3 million – roughly half the advertised price – for the Falcon 1 launch. Exactly what becomes of that contract is still to be determined, according to Musk.

Griswold confirmed the Falcon 1 launch was already partially paid for and said the Pentagon intends to use Falcon 1 for a future launch in support of its operationally responsive space program.

“We are fully confident that once SpaceX finishes its development that this will be a very robust launch vehicle for servicing [Defense Department] needs,” Griswold said.

A spokeswoman following up on Griswold’s behalf said the Pentagon had paid SpaceX $1.5 million to date under the terms of the TacSat-1 launch contract.

Musk said he intends to go through with the launch early next year, whether or not he finds a new payload for the mission. “If there is a satellite out there that is willing to pay us the remaining half of the cost, we will launch them; otherwise we’ll launch empty,” he said.

With the pressure off to launch TacSat-1 for the Pentagon, SpaceX is taking additional time to upgrade Falcon 1 before heading back to the pad for its next attempt. Among the changes being made, Musk said, are switching from an ablatively cooled Merlin 1C main engine to a regeneratively cooled Merlin 1C; swapping out the second stage tank for one made of a stronger yet lighter weight aluminum alloy and upgrading the Kestrel 2 upper-stage engine.

Regenerative engines rely on fluid piped around heat-prone components to keep cool, while cheaper-to-build ablative engines have nozzles specially designed to slowly char but generally require more frequent refurbishment.

With the loss of the TacSat-1 mission, the next satellite launch on the Falcon 1 manifest is the Malyasian space agency’s RazakS

remote-sensing satellite. That mission is slated for the first quarter of 2008.

Musk said he would like to put a smaller satellite with Falcon 1 before conducting the RazakS


RazakSat is a biggish satellite, so we would prefer to launch something smaller first and use that data to tune the vehicle for best performance.

A SpaceX rival was impressed by Musk’s take on the TacSat-1 launch cancellation and its impact on the Falcon 1 manifest. “Elon is a great marketer,” the rival said. “He turns this lemon of an event into lemonade by using the cancellation to broadcast to the world that he has a half-price launch opportunity.”

Jeremy Singer contributed to this article from Boston.