Japan’s university-based space researchers welcomed a government offer of free piggyback flights aboard the nation’s workhorse H-2A rocket, but concerns about the accompanying safety and integration standards tempered their enthusiasm.

The Japan Aerospace Exploration Agency (JAXA) issued a solicitation for candidate payloads weighing up to 50 kilograms for once-a-year H-2A flight opportunities starting in 2008, the agency’s Industrial Collaboration Department said in a May 10 press release. The initial round of proposals is due in August, and to qualify, the candidate satellites must promote space utilization and help train new engineers.

At least 10 applications are expected, Hiroyuki Iwamoto, deputy manager of the Industrial Collaboration Department, said via e-mail May 25. JAXA will announce its selection for a given opportunity no later than 15 months before the scheduled launch, Iwamoto said.

To date, Japan has launched a handful of secondary payloads aboard indigenous launchers with mixed success. The successful December 2002 launch of JAXA’s Midori-2 Earth observing satellite aboard an H-2A also deployed three lightweight piggyback payloads: MicroLabSat, Australia’s FedSat and a Japanese university-built whale tracking satellite.

In February of that same year, however, a secondary payload called DASH failed to separate from the H-2A, whose main payload, JAXA’s MDS-1 satellite, was successfully deployed.

The scarcity of domestic low-cost launch opportunities has pushed university-based researchers in Japan to sign contracts for rides on Russian rockets. Free rides aboard the H-2A could offer a welcome alternative.

“The more options we have the better … I think it’s a good move,” said Rei Kawashima, secretary general of the University Space Engineering Consortium (UNISEC), a group that supports satellite-building activities in about 30 Japanese universities.

“If it goes well, it could be very good for us,” agreed Yasuyuki Miyazaki, associate professor in the Department of Aerospace at Tokyo-based Nihon University. The department intends to enter its 3-kilogram SPROUT nanosatellite, an inflatable structure experiment, as a candidate for a free H-2A ride.

The university has faced a nearly two-year wait for a launch aboard a Russian Dnepr rocket of its SEEDS microsatellite, for various reasons. Contractually, the university had no choice because it couldn’t get its money back.

“We are an experimental payload, not the primary payload. That’s life,” Miyazaki said in a May 24 telephone interview.

Hiroshi Hirayama, a research assistant at Kyushu University’s Space Systems Dynamics Laboratory, said the cost of launching aboard Russian rockets, which he estimated at about 1 million yen ($9,000) per kilogram, make s JAXA’s offer potentially attractive.

However, all three UNISEC members expressed concern that JAXA, anxious to promote the H-2A’s reliability, might saddle its offer with safety and integration rules that university-based satellite makers can neither understand nor afford. The H-2A has had three consecutive successful missions following a November 2003 failure that destroyed a pair of high-priority surveillance satellites.

“Before JAXA announced the opportunity, we were considering any rocket. But we prefer a Japanese rocket because of the language barrier and the contracts. The good thing is that if it’s Japanese, the launch site is near. But the negative things are that there are only two launch windows and JAXA may make the technical criteria higher than for Russian rockets,” Hirayama said in a May 24 telephone interview.

JAXA has agreements with fishermen’s unions that limit launches from the Tanegashima Launch Center in the southern part of Japan to two launch windows spanning a combined 130 days each year.

On the safety and integration side, the concern among university researchers centers on restrictive criteria such as mandating that piggyback payloads launch without their power on, along with checks to ensure separation. Meeting JAXA requirements may be too expensive or too difficult technically for universities and other small-satellite ventures to meet.

“We have limited experience … and generally JAXA’s requirements look quite tough. If they apply some quality control systems, it might be difficult for us,” Kawashima said.

Iwamoto of JAXA said the agency has indeed set strict safety standards for piggyback payloads but is willing to negotiate with applicants and provide assistance. JAXA will announce the detailed safety and interface criteria in July, he said.

Comments: pkk@tkb.att.ne.jp