A question about Spanish Aircraft Carrier Príncipe de Asturias.

[PreMars]

I have recently been reading books about Spanish aircraft carriers and noticed that there are differences in the descriptions of shipbuilding steel used. Which viewpoint is correct?

The first one is "MS, HY and HY-80".


The second one is "MS, HT and HY-80".

 

[Antonio]

Could this "HT" be just a typo?

 

[PreMars]

Could this "HT" be just a typo?

But why isn't "HY" a typo?
Logically, HY includes HY-80. If it is really HY here, why doesn't the author just say "HY" but emphasizes HY-80 specifically?

 

[TomS]

I believe that first example with two uses of HY is a typo and "MS, HT, and HY 80" is the correct version. MS is mild steel, which would be used for most hull plating and bulkheads. HT is high tensile strength steel, which would be the main structural steel. HY-80 is part of a family of high-yield steels that would be used in high-stress areas of the structure.

 

[PreMars]

I believe that first example with two uses of HY is a typo and "MS, HT, and HY 80" is the correct version. MS is mild steel, which would be used for most hull plating and bulkheads. HT is high tensile strength steel, which would be the main structural steel. HY-80 is part of a family of high-yield steels that would be used in high-stress areas of the structure.

I concur. Thanks.

 

[Antonio]

I suggested a typo as an hypothesis because there's some years between the publication of both books.
But as TomS explained the typo is in the most recent book, not in the older as I guessed.

 

[Titus]

Since we are on the subject of this beautiful warship, I also have a question. I've been trying to find out if the Wikipedia article is correct in stating that PDA "carried" 29 aircraft. That must be an emergency overload?
Also, (and yes I know W is not dependable), two GE LM2500 gas turbines for 16,000 tons disp. While the F-100 class FFGs use the same two to move 6,000 tons the same 28 kts? Where am I off?

 

[TomS]

Since we are on the subject of this beautiful warship, I also have a question. I've been trying to find out if the Wikipedia article is correct in stating that PDA "carried" 29 aircraft. That must be an emergency overload?

Yes, that's with a very dense park in the hangar.

I think there is a tendency to overstate the PdA's capacity. It can support up to 12 Harriers and 12 helicopters, but I don't think it every actually carried that many of both at once. In my estimation, the realistic operational load was closer to 18 aircraft -- 12 helicopters and 6 Harriers.

Also, (and yes I know W is not dependable), two GE LM2500 gas turbines for 16,000 tons disp. While the F-100 class FFGs use the same two to move 6,000 tons the same 28 kts? Where am I off?

PdA's sustained speed is lower than 28 knots -- 26 knots seems to be the general consensus. That 2 knots makes a surprising difference in powering demands.

But there is also a counterintuitive thing happening. Longer hulls generate less wavemaking resistance, so bigger ships actually need less HP/ton to achieve a given speed. That leads to unexpected cases where you can actually increase a ship's speed by adding to its length.

 

[PreMars]

Yes, that's with a very dense park in the hangar.

I think there is a tendency to overstate the PdA's capacity. It can support up to 12 Harriers and 12 helicopters, but I don't think it every actually carried that many of both at once. In my estimation, the realistic operational load was closer to 18 aircraft -- 12 helicopters and 6 Harriers.



PdA's sustained speed is lower than 28 knots -- 26 knots seems to be the general consensus. That 2 knots makes a surprising difference in powering demands.

But there is also a counterintuitive thing happening. Longer hulls generate less wavemaking resistance, so bigger ships actually need less HP/ton to achieve a given speed. That leads to unexpected cases where you can actually increase a ship's speed by adding to its length.

I would like to know if its hangar can really accommodate 17 aircraft. The actual aircraft capacity you mentioned is 18, is it because the Spanish do not want to carry so many aircraft?