WASHINGTON — Satellite fleet operator SingTel Optus of Australia has selected Space Systems/Loral to build the SingTel Optus 10 telecommunications satellite following a competition in which Loral bested Orbital Sciences by offering an unusually light version of Loral’s LS 1300 satellite design, industry officials said.

Officials said SingTel Optus 10 is expected to weigh around 3,200 kilograms at launch, which is far less than the usual product produced by Palo Alto, Calif.-based Space Systems/Loral. The company specializes in building large, high-power satellites for mobile communications to handsets, consumer broadband and direct-to-home television. These spacecraft typically weigh 5,000 kilograms or more.

Dulles, Va.-based Orbital Sciences has found a niche at the other end of the commercial market, for satellites weighing around 3,000 kilograms. Loral and Orbital thus rarely meet head-to-head in final rounds of satellite competitions.

By keeping the satellite’s weight down, SingTel Optus is likely to reap savings on the satellite’s launch. For example, it would be able to occupy the second berth of a heavy-lift Ariane 5 rocket that would carry a much heavier satellite alongside it.

If the SingTel Optus 10 satellite were just a few kilograms heavier, launch provider Arianespace would have trouble launching it along with a much larger satellite due to the Ariane 5’s overall capacity constraints. That means SingTel likely would not be able to get the better price accorded the smaller of the two satellites launched aboard an Ariane 5.

SingTel Optus has yet to select a launch services provider for the Loral-built satellite.

Loral and Optus did not immediately respond to requests for comment about the contract.

One industry official said Loral was able to reduce the normal weight of the 1300 platform by employing ion-electric propulsion instead of standard chemical fuel.

Electric propulsion has been used on several Western telecommunications satellites for so-called station-keeping functions, meaning minor motor firings needed throughout a satellite’s life to keep it stably in position in geostationary orbit.

It was unclear whether SingTel Optus 10 will also employ electric propulsion for orbit-raising maneuvers to carry it from its elliptical parking orbit to its final circular geostationary position 36,000 kilometers over the equator.

Peter B. de Selding was the Paris bureau chief for SpaceNews.