Porthole Design Differences

[Bob C.]

This may be a difficult one to get and answer on but does anyone know what drives porthole design?  QE2's 6, 5 and 4 Deck portholes all have rivets surrounding them, presumably for added strength.  At the same time portholes on  Decks 3, 2 and 1 seem more deeply recessed and do not have rivets. 

Any Clydebank designers, cutters or riveters out there that can answer my question?

Pictures:
6 Deck - http://travel.webshots.com/photo/1155073754055338351argCsi

4 and 5 Deck - http://travel.webshots.com/photo/1155073540055338351VkGUUz

3, 2 and 1 Deck - http://www.roblightbody.com/liners/qe-2/jacques/I_8119_REYKJAVIK-060706.JPG

[ancoaster78]

Hi Bob,

Not a factual answer, but my thoughts so far on this issue as I too have been thinkign it through!

The ones lower down have to be more 'sea proof' due to their prozimity to the water, espeically in rough weather when rolling etc. These are the ones therefore that are fitted with the big steel covers that cover the glass sealing them up, I believe the higher ones do not have this is quite the same and so a different fitting would be used that requires being fitted in a different way, presumable by the look of it a stronger way with all the rivets.

Also, lower down a more streamlined shape would be needed for the water passing the hull, so more flush ones rather than the resesed one would be a must, the resesses would really add to the weakness caused by the portholes if water was sloshing into them and gettin trapped there at speed.

As I said, jsut my thoughts to get things started....

Cheers, Andrew

[Bob C.]

Andrew,
     I agree with you 100% and think you are on the mark.  I was just wondering more along the lines of what is between QE2's outer steel shell and the finish work inside the staterooms.  I think seeing/knowing that would provide the insight on why the 3 Deck and above portholes are recessed and what the purpose of the rivets are for 4 Deck and below. 

Thanks!

[Peter Mugridge]

the resesses would really add to the weakness caused by the portholes if water was sloshing into them and gettin trapped there at speed.

I would have thought that recesses would also add a bit of drag, would they not?

[ancoaster78]

Yes deffinatly they would! Especially when theres so many of them 

[Twynkle]

Hello!

Is the shape, and size of a porthole dictated by it's position, and linked with the need to avoid 'stress' on the hull?
Perhaps higher up the hull it is 'placed', the greater the stress, as it gets nearer to the 'join' with the aluminium?
Cheers
Rosie

[highlander0108]

Commodore Warwick discussed how the portholes are not original in the ship, at least the round ones down low in 4 and 5 deck.  He stated that the originals were aluminum to save weight, but they never got the isolation from the steel hull fully worked out and the units were corroding in place.  He went on to say that he had saved a few that were taken out up in his attic and that when he went back to look at them recently, they had all completely disintegrated.  Here is a photo of his slide used in his lecture onboard QE2. 

I believe that the larger units up one the higher decks were purely due to these cabins being the larger first class cabins and have nothing to do with any structural aspects of the hull design, but perhaps Flagship can confirm this and offer more background on when the original aluminum units were replaced.