What was this ?

[Miles]

Seen at night, clearly a vessel and as we closed the following became visible in this order :

1. At some distance, a very quick flashing yellow light flashing in short bursts. Other lights visible but not distinguishable.

2. Closer to, cabin lights, a red port light and a white over red light.

3. Then as we got still closer we saw in line and astern of the same vessel, a line of six red lights which gradually became six pairs of two red lights one above the other and the top one of which was seen to be occulting once every six to eight seconds.

It took us a while to work it out and I wonder how many people would know immediately ?

 

[jimi]

Something to give a wide berth to?

 

[oldharry]

Sounds like a UFO with all those flashing lights. Not cigar shaped by any chance?

UFO - Unidentified Floating Object

Darn, of course it was those chinese lanterns again....

 

[Coaster]

Where exactly were you when these lights became visible?

 

[KenMcCulloch]

The flashing yellow light is usually a hovercraft unless you are in the Aegean where it's most likely a hydrofoil. As to the rest I can only suppose you had been ingesting hallucinogenic mushrooms or had been abducted by aliens.

 

[Sgeir]

The flashing yellow light is usually a hovercraft unless you are in the Aegean where it's most likely a hydrofoil.

Yes, although it might also have been a fast moving fish farm or a mini-cab office. We've seen flashing yellow lights used by a submarine (and/or accompanying vessels) during sea trials at night in the Clyde.

 

[Richard10002]

All round white over red is a pilot boat, (IIRC - the white of his hair, then the red of his face, as he appear over the gunwhale).

The trail of red occulting, over red, suggests some kind of tow, with lights based on a local rule?

Yellow flashing could be hovercraft, yellow over stern light could be towing

red occulting could mean dangerous cargo.

So I'll plump for a pilot vessel towing a dangerous cargo.

Or are you on the US Lakes/US Inland Waterways?? In which case, all bets are off

 

[VO5]

A Sea Monster...Give a Wide Berth Immediately !

 

[Martin_J]

Sailing down the Thames you see...

A bridge with a dustcart crossing it... flashing yellow and disappearing occasionally behind bridge pillars... or a flashing cone.. with cars passing in front on the same bridge...
Closer to... White over red (pilot ahead).. so you're seeing the port side of the Pilot boat coming towards you under the bridge.
.. and in the distance is a TV mast with solid red lights (four on each level but you can only see two at each level) and at the top of the mast a single occulting red.

Which TV mast or chimney is anyone's guess.

 

[Miles]

Pilot Vessel and Wind Farm in line.

We were off the Dutch coast at the time and the vessel was indeed a Dutch or Belgian pilot vessel. We worked out the white over red was a pilot vessel when we distinguished it from his other lights. We could see his name on AIS so slowed and called him up on VHF. We were worried about what the flashing yellow light meant and whether he had a tow of some weird sort - we were routed to pass astern of him though we couldn't work out why a pilot boat would have anything under tow.

He said that the flashing yellow light was used for identification purposes as they were picking up the pilot from an outbound ship which we then saw closing with him but some way off on our port side.

By this time we were close enough to see that the flashing red lights were also some way off and were not part of a tow. He had also confirmed that he was entirely happy for us to pass astern of him and resume our south westerly course. There was nothing on our radar chart plotter screen (charts new this year) to explain what they were but when we got out the paper charts we realised that the red lights were the six towers of a wind farm. The top occulting red lights were in fact the blades of the turbine passing in front of the light.

I haven't been able to find any reference to flashing yellow lights being used by a pilot boat for identification purposes and could see why it was necessary when he and the ship he met had AIS and VHF but perhaps it has been used for many years in that area. We had ruled out hovercraft as a possibility but had wondered about some sort of fishing boats(s) until we saw his white over red light. AIS had shown him moving at 2-3 knots for some time so the possibility of this being some sort of fishing vessel wasn't ruled out until that point.

The lessons (and the reason for posting) were that this was a good example of the need for the paper charts that gave us the answer and that in our first night time encounter with a wind farm we had been confused by the height of the wind farm towers which had meant that they initially appeared much closer than they were and which had seemed to be line astern of the much closer vessel. We try not to fall back on VHF when AIS shows a small CPA value but on this occasion it was useful in clarifying both his and our intentions.

If any of the above seems less than clever on my part it all happened at around 2 am on an inky dark night. In future I will make a point of checking for wind farms when making a passage plan for unfamiliar coastal waters.