Length aloft

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Oct 18, 2020
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Hy Guys.
On my "Investigator reconstruction I have a few discrepancies.
As the Fram (single decked collier) she was described as 100 feet aloft. Depth of hold 19'
After the gun deck was built below the upper deck it was described as “Length of gun deck 100’ 4” “ height between decks 7'6" Depth of hold 12' 6"
It all seems OK but I don't see how the lower deck can be longer than the upper deck.

What is the definition of:

1/ Length aloft

2/ length of the gun deck

3/ length extreme.

4/ length on the range of the upper deck

The normal starting point is distance between perpendiculars which usually coincides with the distance between the inner edges of the rebet at the height of the lower deck.
But as the lower deck was added later it’s not a good starting point.
Hit me with any definitions of these terms you have to help me reconcile the problems.

Regards
Allan
 
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It all seems OK but I don't see how the lower deck can be longer than the upper deck.

from what i see the lower deck is not longer than the upper deck
blue arrow is the upper deck and red arrow is the lower deck


Screenshot (157).jpg
 
It all seems OK but I don't see how the lower deck can be longer than the upper deck.

from what i see the lower deck is not longer than the upper deck
blue arrow is the upper deck and red arrow is the lower deck


View attachment 245780
Thanks Dave. Perhaps my post was a bit lacking.
From official records of Fram. She was recorded as being 100 feet aloft. The navy then added a second deck (gun deck) below and then it was recorded that she was 100ft 6in on the gun deck.
My reconstruction above was based on a distance between perpendiculars of 98' 11" derived from tonnage breadth level length for tonnage etc. The 2 figures quoted don't add up unless the definition of length aloft is the distance between stem post to stern post on the upper deck. Or something like that. Or the second record is actually the upper deck. Hence I was asking for the definition of the various lengths. Trying to find a reason for the discrepancy is hard. I am more than happy with the plans so far. The ship was a collier and there is no doubt she would have looked something like my plans. When purchased she was described as a single deck ship without galleries. Others have come up with plans with quarter galleries and other features that are nothing like a collier Anyhow the mystery continues. Thanks for your thoughts. Regards Allan
 
the confusion may be in the definition of "aloft" it seems to have nothing to do with a measurement of the hull but a term used in rigging of a ship

aloft
1. In the rigging of a sailing ship.
2. Above the ship's uppermost solid structure.

Admiralty: The governing board of the Royal Navy.
Aloft: measurements Going up the mast.

At or on or to the masthead or upper rigging of a ship

measurement from the mast step to upper most masthead
 
if aloft is a rigging measurement and you have a depth of hold of 19 feet the the very upper tip of the main mast is 81 feet above the deck
 
UhIt all seems OK but I don't see how the lower deck can be longer than the upper deck.

from what i see the lower deck is not longer than the upper deck
blue arrow is the upper deck and red arrow is the lower deck


View attachment 245780
Thanks Dave. Perhaps my post was a bit lacking.
From official records of Fram. She was recorded as being 100 feet aloft. The navy then added a second deck (gun deck) below and then it was recorded that she was 100ft 6in on the gun deck.
My reconstruction above was based on a distance between perpendiculars of 98' 11" derived from tonnage breadth level length for tonnage etc. The 2 figures quoted don't add up unless the definition of length aloft is the distance between stem post to stern post on the upper deck. Or something like that. Or the second record is actually the upper deck. Hence I was asking for the definition of the various lengths. Trying to find a reason for the discrepancy is hard. I am more than happy with the plans so far. The ship was a collier and there is no doubt she would have looked something like my plans. When purchased she was described as a single deck ship without galleries. Others have come up with plans with quarter galleries and other features that are nothing like a collier Anyhow the mystery continues. Thanks for your thoughts. Regards Allan
 
Dave that is a possibility. It's interesting how one person can make an assumption and it gets accepted universally as correct.
This length aloft has been taken as the deck length by others and now seems indisputable. However I will now go to the masting as the keel to truck length is probably around 100'. If that's the case I will disregard it as a hulk dimension. Thanks. Allan
 
This answers the question I think.

RECORDS OF BRISTOL SHIPS
1800—1838 (Vessels over 150 tons)
LENGTH. The length measurement in a register was the extreme length aloft, under' old measurement' rules, but under' new measurement ' it was the upper deck length, which would be shorter than the former by the omission of the stem and stern post thicknesses.
Old measurement = Length from the inner part of the main stem to the fore part of the stern aloft.

It still doesn't answer why the gundeck ended up longer than the upper deck. I think maybe it was actually the upper deck measurement. Which all fits in.

Allan
 
This answers the question I think.

RECORDS OF BRISTOL SHIPS
1800—1838 (Vessels over 150 tons)
LENGTH. The length measurement in a register was the extreme length aloft, under' , but under' new measurement ' it was the upper deck length, which would be shorter than the former by the omission of the stem and stern post thicknesses.
Old measurement = Length from the inner part of the main stem to the fore part of the stern aloft.

It still doesn't answer why the gundeck ended up longer than the upper deck. I think maybe it was actually the upper deck measurement. Which all fits in.

Allan

that is a curious statement seems like aloft should be afloat

a shot in the dark but maybe aloft is defined as the hull above the water "the waterline"

i do know ships were measured at the waterline for docking fees which might of been the old measurement' rules
then it seems like new measurement rules measured a ship from the inside of the stem and stern post. which would be shorter than the old waterline measurement

Old measurement = Length from the inner part of the main stem to the fore part of the stern aloft.

extreme length aloft,


to me extreme includes the stem and stern post
 
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