UPDATE 1-Hansen Transmissions swings to H1 loss

* Pretax loss of 9.6 mln euros vs 31.7 mln last year

* Reduces net debt in Q2 by 45 mln euros to 180 mln

* Sees growth in Chinese market, secures second deal

* Shares reverse early losses to trade up 2.7 pct

(Adds detail, share price)

LONDON, Oct 26 (Reuters) - Belgium-based wind turbine gearbox manufacturer Hansen Transmissions (HSNT.L) swung to a pretax loss in the first half, hit by lower-than-expected volumes, and said the short-term outlook remained volatile.

However, London-listed Hansen said there were signs of improvement with China experiencing significant volume growth and said it had recently secured a second contract with a Chinese customer.

The company posted a pretax loss of 9.6 million euros ($14.4 million) in the six months to end-September, against a profit of 31.7 million last year.

Revenue fell 3.1 percent to 286 million euros, but reported a 9.9 percent rise on the previous quarter.

"This revenue decrease was due to a reduction in scheduled deliveries of wind turbine gearboxes as Hansen worked with customers to manage their requirements in line with the current operating and credit environment," said the company in a statement. "Near term visibility on new wind turbine orders remains uncertain," it added.

More expensive debt has dented the development of large-scale projects to generate renewable energy from the wind and sun, despite government steps to fight climate change.

"The current market conditions do not support the efficient utilization of all of the manufacturing capacity. However, the company anticipates that this situation will ease during the second half of this financial year," it added.

Hansen, which supplies gearboxes to four of the five largest manufacturers of gear-driven wind turbines globally, said it reduced its debt by 45 million euros in the second quarter to 180 million at the end of September. It repeated its guidance of flat revenue for 2010.

Shares in Hansen were up 2.3 percent at 1018GMT, after falling as much as 1.7 percent in early trading.

(Reporting by Farah Master; Editing by Lorraine Turner)

($1=.6664 Euro)