Katherine Tee, 41, was sailing from India to Thailand and was on night watch on the deck of her Kalik 40 yacht in early March when she claims she saw a plane surrounded by bright orange lights and with a tail of black smoke pass above her.

Ms Tee's husband, Marc Horn, 50, was asleep below deck at the time and another crew member was asleep on deck when she saw the strange occurrence, which she has only recently reported to the Joint Agency Coordination Centre (JACC) in Australia.

She now believes it may have been Malaysia Airlines flight MH370, which went missing on March 8 on a flight from Kuala Lumpur to Beijing with 239 people on board.

"It caught my attention because I had never seen a plane with orange lights before, so wondered what they were," Ms Tee, from Liverpool in England, wrote in the online sailing forum Cruisers Forum, where she also works.

"I could see the outline of the plane, it looked longer than planes usually do. There was what appeared to be a tail of black smoke coming from behind it.

"There were two other planes passing higher than it - moving the other way - at that time. They had normal nav lights. I recall thinking that if it was a plane on fire that I was seeing, the other aircraft would report it.

"As I first observed it, it was approaching to cross behind our stern from the North. When I checked again later it had moved across the stern and was moving away to the South."

Ms Tee, who has also written about her experience on her blog, did not initially report her sighting to authorities or even to her husband, she said, as they had been at sea for 13 months and were having relationship difficulties.

But recent media reports about the difficulties with the search off the West Australian coast had convinced her to come forward this week, she said.

"We hadn't spoken for about a week," Ms Tee said, referring to her relationship with her husband at the time of the sighting.

"The first time I told him was last night after hearing the radio report. That is when we checked our GPS log and realised that perhaps I really did see it.

"I did think [initially] that what I saw would add little, and be dismissed with the thousands of other sightings I assumed were being reported; I thought that the authorities would be able to track it's [MH370's] GPS log which I assumed was automatically transmitted, etc.

"And most of all, I wasn't sure of what I saw. I couldn't believe it myself. I even doubted my sanity, and didn't think anyone would believe me when I was having trouble believing my own eyes. So I dismissed it, and got on with the business of fixing me and my marriage.

"All I can confirm is that I learnt last night that we were in the right place at the right time, so it seems possible."

Ms Tee and her husband were sailing from India to Thailand at the time, and the couple are now in Phuket. Ms Tee told the Phuket Gazette that she had filed a report with the full data from their voyage to JACC.

JACC has been contacted for comment.

Authorities last week said the Australian-led search in the southern Indian Ocean would continue for possibly another year.

The Australian Transport and Safety Bureau will call for tenders this week for vessels and sonar equipment to continue the hunt for the missing plane.

A Chinese ship has already begun conducting mapping of the Indian Ocean sea floor, so that sonar equipment can be towed safely and obstacles avoided.

The current search has been paused, after authorities concluded that a series of "pings" heard in the intensive search area were generated by search equipment and not the aircraft's black boxes.

Fairfax Media