Woodside on track for Myanmar development plan by end-2018 - CEO

* Myanmar well finds "unrecoverable" gas

* No impact on operations from Rohingya crisis - CEO

* Cuts top end of full-year output forecast to 90 mln boe

* Q3 revenue down 7.5 pct on year; shares drop (Recasts with CEO Coleman interview, analyst comments)

By Christina Martin and Sonali Paul

Oct 19 (Reuters) - Woodside Petroleum played down disappointing results from its exploration wells in Myanmar on Thursday, with Chief Executive Peter Coleman saying the company is still on track to decide on development plans there by the end of 2018.

Australia's top independent oil and gas producer cancelled plans for a seismic survey in Myanmar after drilling five wells scheduled for 2017, Coleman said in an interview, confirming a Reuters report this week.

Coleman was speaking after Woodside cut its full-year output forecast, reporting third-quarter revenue fell 7.5 percent from a year earlier to $914 million, missing some analysts' forecasts. Shares slipped as much as 2 percent.

A well on the A6 block off the southwest coast of Myanmar found only residual gas which was "unlikely to be commercially recoverable", Woodside said, while a well in Block AD7 off the northwest coast hit "water-wet sands", following three finds earlier.

Coleman said the company had decided not to go ahead with extra seismic work as it already had enough information to digest ahead of drilling in 2018.

"In the end we decided we were already pretty much stretched on where we were and it was prudent for us to stop," he told Reuters.

Woodside is among the biggest holders of petroleum acreage offshore Myanmar, where its partners include majors Royal Dutch Shell and France's Total SA, and has targeted the country as a key source of growth after 2021.

"We've really said by the end of 2018 we will know what the development looks like in Myanmar," Coleman said. "We're still on schedule for that."

Coleman said the Rohingya refugee crisis in Myanmar had not affected offshore operations at all, but the company did have to cancel talks with some fishing communities in troubled areas.

"It's something we're obviously concerned about, we're watching closely," he said.

Analysts said the latest drilling results were not a big setback for its aspirations in Myanmar.

"They've had a successful run so far. The law of averages says there's going to be a dry hole every now and then," said John Hirjee, an analyst at Deutsche Bank.

For the full year, Woodside narrowed its guidance range to 84 million to 86 million barrels of oil equivalent (mmboe), lowering the top end from 90 mmboe due to the slightly delayed start-up of the Wheatstone liquefied natural gas project, run by Chevron Corp. (Reporting by Christina Martin in BENGALURU and Sonali Paul in MELBOURNE; Editing by Stephen Coates and Kenneth Maxwell)