LR/IMO numbers on older vessels

[davidships]

On a member's photo a discussion has arisen about LR/IMO numbers for vessels whose existence ended 1963-1998, and therefore had a unique LR number, but with only 6 digits.  It is more appropriate to discuss this here where it can attract wider viewing and contributions, so I am moving it from http://www.shipspotting.com/gallery/photo.php?lid=2890363

Bj

[davidships]

We do not need to dwell further on the particulars of the case above/below, but can address the broader question about ships that did get unique LR numbers, but only six digits because they did not survive to 1969.  This has been discussed before, perhaps on this forum, but certainly in the Admin Forum in 2015, though I cannot recall the outcome.  At present I cannot access any forum threads before some time in 2017 due to the still-unresolved problem of Tizermedias diversions, but for Admin colleagues' reference it is at http://forum.shipspotting.com/index.php/topic,14400.0.html.  

Strictly speaking 7-digit unique "IMO numbers" only came into existence on 1/1/1996, but as IMO adopted the existing Lloyd's Register numbering system, this covers all vessels that have appeared in LR from 1969.  In my view all those numbers can be considered as LR/IMO numbers, and that has been our practice for some time.  I am not aware of any objection to that.

The question at hand concerns that ships that had unique 6-digit LR numbers allocated to all existing ships in 1963, and to those added prior to 1969, when the seventh so-called check digit was added at the end.  Those numbers are in principle part of the same series as the later numbers, but LR did not see any point in adding the extra digit as the Register only covered vessels then current.  Prior to 1963 there was no global unique (ie, cradle-to-grave) numbering system in LR or, so far as I know, elsewhere.

Apart from being factual staments, we use IMO numbers for the important practical tank of linking all the images of specific ships regardless of what name they are carrying at the time, or the category that the images are in.  This facility is much valued and works well, but it is limited to those ships that have such numbers (excluding therefore virtually all warships and smaller fishing boats, work-boats, tugs etc and a large proportion of motor yachts as well as all vessels out of service by 1969.

So (with apologies for going on at such length), views are welcome on that.

[pieter melissen]

David, for this site, as you state correctly, having a unique number is essential for a number of functions. To me it is of less importance whether that is a "correct" IMO number or anything else. As long as it is really unique, there can be no confusion about which ship we are talking about. Therefore, while covering an interesting point in the history of the LR/IMO numbers the first post in this thread has only academic value as far as the site is concerned. I think in respect we cannot praise MIRAMAR enough for the work they did to get their files organised, and I have absolutely no problem with using their number as a proxy IMO number if needed. It helps us, it helps the site and the site community, even though some of us know that it might be technically incorrect.

In short, be practical, make use of the options and live with the incorrectness.

Perhaps there are people brave enough and with enough free time to sest up a numbering systeem (7-digits?) for the ships that can now not be covered in the site retrieval systems, but as these comprise categories in which I have very little interest, I am not volunteering.
  

[Bob Scott]

The seventh or

[pieter melissen]

Bob, thank you for the explanation, it is beyond me why it had to be so complicated, but the issue was rather why we cannot use numbers that "look" like IMO numbers, but will fail the test. (as Miramar obviously does). As long as they are unique, I am fine with that. Lloyds Register is not the Bible, although they sometimes disaggree with that.

[Bob Scott]

Pieter, I know you have a less than enthusiastic view of Lloyd's Register but, in the absence of anything else that is better and widely accessible, LR will have to be the nearest thing to "the Bible" for our situation

[davidships]

Just for info at this point:

There would be a couple issues with using Miramar serial numbers:
1) some IMO numbers being issued (eg yachts in the 1------ series) have already been used by Miramar for other vessels - though I have a hunch that Miramar is changing those existing numbers as those come to light - which raises a question in itself about reliability
2) about one tenth of Miramar's internal numbers are compliant with the IMO number formula, including the 55----- numbers converted from 6-digit LR numbers) and could well be issued as IMO numbers in the future.

The Miramar number set may be subject to copyright, and in any case permission would be required to use it (not that I would expect any resistance from Rodger Haworth).

On the subject immediately to hand, we could stretch our own definition of "LR/IMO number" to include the 1963-1968 unique numbers - there are not very many of them and they could be constructed as and when required. I understand that these numbers will not in future be issued to new ships.

If we are talking more broadly, applying unique numbers to vessels which currently do not have 7-digit LR/IMO numbers nor appear in the Miramar database, would be a mammoth task.    They would have to be called something other than "IMO number". And members would not be able do anything beyond copying numbers already used for the same vessel - there would be no external database to refer to.

I think that it is unlikely that any development that involved software changes to the site could be achieved in the short term.

[OceanCraft]

At OceanCraft we have constructed our own database to remove the confusion over IMO numbers.  We always work with the six-digit number as the key field in the database regardless of whether it is an LR number or an IMO number.  This is a problem with the Miramar database in that they chose to use the seven-digit IMO as a key field and then were stuck when they came to the six-digit numbers.  They chose to add a 5 at the beginning of the number as the 55xxxx series of numbers was not used.  This then causes problems within the ShipSpotting website as some posters choose to use the Miramar version and other use the six digit (IMOised) with a check digit at the end which is not strictly correct (and which is the point raised by Phil English).

From the OceanCraft database, the six-digit series appears to be in two primary groups, 50xxxx series and 54xxxx series.

The 50xxxx series (six-digit IMO) introduced in 1963 was applied to the list of ships in Lloyds in alphabetical order of the ship's name it carried in 1963.  This series ranged from 500001 to 539965, so this covers almost 40000 ships.

The second series of 54xxxx was used and this appears to be for ships built in 1963 after the application of the 50xxxx series and ships which experienced a name change in 1963.  This runs from 540001 to around 542950, so about 2950 ships and is applied in five alphabetical A-Z groups.  The only explanation we have for this is that the 50xxxx series was implemented in, say, July 1963 and the 54xxxx series was applied at the end of each month remaining in 1963 to those ships which either entered service or changed name within that month.  From 1964 the 64xxxx series was used.

Every number of both series was used and covers all ships extant in 1963.

There is evidence of 56xxxx, 57xxxx, 60xxxx series, (and possibly 61xxxx series, but this could be another Miramar 'invention') but we are still collating and evaluating these.

We hope the above info will be of some use but we do not know what the solutions is for the ShipSpotting website.  It is looks as if ShipSpotting is a gallery of photos trying to have some structure without a database, where it really needs to be a database with structure linking to a gallery of photos.  Discuss.

OceanCraft Models
www.oceancraft.co.uk

[simonwp]

My personal preference would be to forge some sort of link with Miramar, and use Miramar not only for IMO / Unique vessel#'s, and also for classifying vessels. It won't be 100% perfect, but it's probably the best option available. If the site rules direct members to Miramar as their source of information, then at least there will be an element of consistency, even in the cases where it is not 100% correct. It would also eliminate the problem of different admins using different sources of information for both IMO#'s and vessel classification, and sometimes making incorrect changes. However, as we know, Miramar is a subscription service, which may be a problem for some, and make it difficult to have a formal tie in.

[Bj]

Hello
Here is a link where you can try it out yorself about IMO numbers.
http://tarkistusmerkit.teppovuori.fi/coden.htm

[pieter melissen]

Quote of Oceanquest "It (is) looks as if ShipSpotting is a gallery of photos trying to have some structure without a database, where it really needs to be a database with structure linking to a gallery of photos. "

There used to be a connection with a database, Gross Tonnage, but they ceased to operate a couple of years ago. The data supplied below each picture on SS are still from them. As they stated themselves before their demise, they were focussing on "interesting ships", and they declared older ships as "not interesting", hence the sometimes rudimentary information on ships that ceased to exist a long time ago. Unfortunately it has not been possible to find a replacement database for Gross Tonnage, which more and more results in data om new ships being incomplete. This is another problem than the IMO number, but also here the way to go could be Miramar. In my ideal world Shipsspotting would be something like an illustrated Miramar, and if that would imply using their numerical systems, let it be that way, as long it it helps Shipspotting to have easy access to all photo's of one unique ship, irrespective under which name the pictures were posted.

The category system on Shipspotting is much more advanced than that on Miramar, so that either would have to be sacrificed, or being maintained manually with the first input coming from the poster with correctors to check that.   

[simonwp]

Pieter, I've said this before, but I think the category system on Shipspotting is TOO advanced. It is too complicated and needs to be simplified, so going down the Miramar route might solve two problems at once.

[Pilot Frans]

Intresting to know I how the IMO/LR was put in force and how to calculate the check digit.

But I think the main purpose of the numbers is that you can trace back the vessel, during her/it's lifetime.
By putting in the IMO-field number multiple pictures are linked. This gave me (and others) a good view of the lifetime and namechanges through the years.

So in my opion it doesn't matter which number is used as long as it is an unique number.

I'm not familiar with Miramar, but if they have such unique number, that's fine to deal with. So it's easier to find picture of a unique ship

regards
Frans

[davidships]

This discussion rather faded without leading to any definite conclusion, but was revived in photocomments yesterday with following:

adenanthos on Nov 28, 2018 21:42    
Who cares about the fact that 5607782 is not an official valid IMO number, we only use this Miramar number in order to group all the photo's together, not everyone will now be aware that there are several nice other pictures of this vessel on the site.
This same discussion was made some time ago on this forum and it was then agreed to allow it this way only for reasons of getting the same photo's of a certain vessel together.
After all "Shipspotting" is not an official Government or Maritime institution.
May be we should add "Miramar" to the IMO/LR entry

pieter melissen on Nov 29, 2018 10:12    
Adenanthos, agreed...

Views from more members are welcome.  I am also asking Admin colleagues for their views on the technical aspects.

[Pier Master]

I like this part, "we only use this Miramar number in order to group all the photo's together", makes perfect sense to have some sort of central reference point. The IMO/LR or whatever else you want to call it does exactly that.

Perhaps we could get the same from the ENI number...

Regards, Brian.