BEIJING -- China is planning its first sea-launch of satellites carried by a Long March rocket, according to an aerospace official.

Yang Yiqiang, commander-in-chief of the Long March-11 rockets project of the China Aerospace Science and Technology Corporation, said that 2018 would see five launches of Long March-11 rockets, with four missions for commercial payloads on land, and one at sea.

"The sea launch will meet the growing needs for launching near-equatorial and low-inclination satellites, and improve the rockets' adaptability," Yang said. "The solid-propellant Long March-11 rockets have strong quick-response ability with low prices, which provide better, competitive services in space commerce."

Launches in the equator region are more fuel-efficient. They cost less but demand a more stable rocket performance, which is affected by sea waves and high temperatures.

Wenchang, centered at 11 degree east longitude and 19 degrees north latitude, in South China's Hainan province, is the only launch center near the sea. As for missions with an inclination of zero to five degrees, the sea launch will fill the gap.

China started developing modern carrier rockets in 1956, and the Long March rockets have become the main carriers for China's satellite launches.