Aurora's turned back!

[Brayman]

Aurora left Lisbon earlier today on it's way back to pick us up in Southampton on Friday, it now looks to have turned back and heading back into Lisbon.

[CCFC]

How odd, it didn't get very far before turning back, maybe a medical emergency?

[jeanlyon]

Can't get her on AIS, but webcam definitely shows her in Lisbon.

[jeanlyon]

Just got her on Vesseltracker - defiitely in Lisbon as of 26 minutes ago.

[Brayman]

Just got her on Vesseltracker - defiitely in Lisbon as of 26 minutes ago.

 

Marine Traffic shows her outside Lisbon having turned back some time ago.

[BrianI]

If you look on marinetraffic.com you can see Auroras track and she has definitely turned back. Currently stationary just off Cascais.

We were on the last Aurora cruise and we turned back to Almeria for a medical evacuation. The ships medical team went ashore with the patient and we waited for them to return. Overall it took seven hours to get back to the position we diverted from but we still arrived at the next port, Messina, on time.

 

Brian

[Corfe Mixture]

As of 2100 hours UK time she is lying to anchor just under 2 nautical miles south of Cascais.

 

Turned back at 1740 hours UT

Dropped anchor at around 2000 UT

 

Whatever happened she did an emergency turn as these ships don't stop quickly or make tight turns at speed and she went from 20kts to over 13 knots and accelerating on a reciprocal course in just 13 minutes. That is virtually a crash stop and turn which suggests a sudden event.

 

Doesn't make much sense. Wouldn't have thought they would have done a crash turn for a medical emergency, but doesn't sound like a collision with a smaller vessel, or any other form of rescue, as she would have come to a stop whilst effecting a rescue and she immediately picked up speed and headed back south.

 

Difference of two knots between speed going North and Speed returning south is almost certainly tidal effect.

Edited July 8, 2014 by Corfe Mixture

[rooftop]

Well she's on the move again.

[Corfe Mixture]

Well she's on the move again.

 

2315 BST. Less than 2nm short of the position she was in when she turned back.

 

Got more detail on the turn. She slowed from 20 knots to 12 knots in less than five minutes and then made a 30degree per minute turn at 10kts which and was on a reciprocal course within 6 minutes having covered just 1nm whilst making the complete 180 degree turn.

 

Must have been some experience for those on board when she made the turn as that just had to be her maximum rate of turn and there would have been quite some heel. Guess they must have had calm seas.

Edited July 8, 2014 by Corfe Mixture

[jeanlyon]

AIS and Vesseltracker can be minutes or even hours behind, so what looks like a crash turn maybe isn't. I work with the lifeboat crew at Salcombe and we are always looking at things like this.

 

I see she is underway now at 20knots

Edited July 9, 2014 by jeanlyon

[Brayman]

AIS and Vesseltracker can be minutes or even hours behind, so what looks like a crash turn maybe isn't. I work with the lifeboat crew at Salcombe and we are always looking at things like this.

 

I see she is underway now at 20knots

 

On MarineTraffic.com, as Brian said above you can see the track of the vessel and see that it left Lisbon heading up the coast and then did a fairly sharp turn to return to the mouth of the river where it was stationary for quite some time before setting off again.

[T4TC]

Went to the aid of a Cargo ship that was at anchor, medical emergency?

 

 

Sent from my iPad

[Clodia]

Sounds like aiding another ship or searching for something. When I was on Oriana in 2005 she did a similar turn as something had been spotted in the sea which may have been a small upturned boat. (it wasn't). At least the captain told us what he was going to do and why; it was quite exciting when she turned.

[Corfe Mixture]

AIS and Vesseltracker can be minutes or even hours behind, so what looks like a crash turn maybe isn't. I work with the lifeboat crew at Salcombe and we are always looking at things like this.

 

I accept that there can be a delay in information arriving from internet AIS sources, but I was looking at a track where I had the benefit of five course, speed and positions fixes taken over a period of 10minutes.

 

I had three Course and Speed fixes made during the turn and the data I gave included the fix before the turn commenced and the fix after the turn was completed.

 

The information may have been delayed, by the data presenter, but the sequence and time stamps were valid.

 

I appreciate that one can get the strange results you allude to with Class B AIS sets, as fitted to yachts - especially when they are at the limit of their VHF transmission range from the receiving station.

 

However, Aurora will be equipped with Class A AIS and the situation occurred in close proximity to land, and ell within range for a Class A station.

 

The data time stamped data would therefore be as detailed and accurate as the AIS data which clearly showed not only which rock Costa Concordia struck, but also the course change which occurred as a result of the impact.

 

IMHO, as a yachtsman familiar with AIS, though clearly not as familiar as your RNLI friends, there is no doubt that there is sufficient data to conclude that:

Aurora made maximum rate of turn change to a reciprocal course over a period of six minutes with a rate of turn of 30 degrees per minute at a speed of10 knots.

Edited July 9, 2014 by Corfe Mixture

[jeanlyon]

Yes, understand what you are saying, but it's the same with Class A - it can be minutes out of date or even hours. wonder what she turned for.

[Tapper lady]

PO responded to query about Aurora turning back, and there reply was:- Aurora turned back to port for a medical landing. Once the passenger had safely reached land, Aurora was back on her way.

 

Vanessa

[rooftop]

Yes, understand what you are saying, but it's the same with Class A - it can be minutes out of date or even hours. wonder what she turned for.

 

It doesn't really matter if the data is minutes or hours out of date - for the casual observer at least - providing that the timestamp data is consistent with itself. i.e. the timestamp is always transmitted from the ship along with its velocity data.

[Corfe Mixture]

Yes, understand what you are saying, but it's the same with Class A - it can be minutes out of date or even hours. wonder what she turned for.

 

Sorry, you do not appear to understand what I have said.

Class A units transmit the following data from the ship's own onboard sensors:

Speed over ground to an accuracy of 0.1knot

Positional Data - accurate to 0.0001 minutes of latitude and longitude

Course over ground – accurate to 0.1°

 

They also transmits rate of turn, but I did not get that data

 

Yes an internet provider / receiving station can be slow in making the data available, and if you are distilling data from differences between position fixes, then you can get some funny results.

 

You can also get funny results from yachts and power boats if their information source is simply the onboard GPS deriving information from consecutive CA (coarse acquisition) code fixes which is not being supplemented by DGPS data.......

 

BUT, if you have sequential plots of the above data, from a Class A AIS transmitting ship's sensor data, at intervals of less than two minutes, you can certainly see exactly what happened.

Edited July 9, 2014 by Corfe Mixture