New Gran Colombian Ships for 1914

[Guinness]

The funnel trunking is interesting. Was the idea that airships should approach from either side?

For a specialized airship tender, I wonder if an airship mast well aft with ships funnels well forward might make more sense. I guess you'd still have the problem of how the crew exits the gondola.

[The Rock Doctor]

The notion's that the airship either approaches obliquely from behind, or from directly astern - in which case the blimp's through the exhaust plume by the time it's within "danger distance" of the mooring mast.

I contemplated the other layout you mention, but felt that the Colombians would want to actually land the blimp in order to swap crews, fuel it up, and so forth.  Whether any of that is actually practical remains to be seen.  This could turn out to be a complete boondoggle.

[The Rock Doctor]

Correction on a point - the SSZ type blimps I've modelling mine after had a volume of 20,000 cubic metres .  That means it's a Type 1 airship by our rules, not a Type 0.

[The Rock Doctor]

The SS for the airship-tendering-cruiser-amabob pictured earlier in the thread.  Weight estimates are just me picking numbers that are probably conservative.

The hull form is similar to the Boyaca class cruisers, except slightly shorter and with a more rounded stern (hence the higher BC).

The ship would have room for maybe thirty "ground crew" and one or two extra airship crews (three to six men total); given that the ship is underarmed for its size, I don't feel compelled to provide extra accommodations.  They can replace the gun and torpedo crews I don't have here.

The ship is, in theory, a forward operating base for airships that might be operating in scouting roles with the Armada.  Being able to fuel them, rotate out the crews, and fix a few minor problems should enable the airship(s) to remain in the vicinity of the fleet for a full day or more, rather than having to head back to the nearest coastal hanger.

The ship retains many cruiser characteristics, including battery, armor, and speed.  This is primarily for the sake of her own survival, since she's not suited to surface combat. 

If it works, it may inform future GC carrier doctrine.  If it doesn't, she may wind up converted to some other function in a couple of years.


IX-7, Airship-tending-cruiser, laid down 1912

Displacement:
   3,498 t light; 3,607 t standard; 4,110 t normal; 4,513 t full load

Dimensions: Length overall / water x beam x draught
   391.30 ft / 387.14 ft x 42.65 ft x 18.54 ft (normal load)
   119.27 m / 118.00 m x 13.00 m  x 5.65 m

Armament:
      2 - 5.51" / 140 mm guns in single mounts, 83.72lbs / 37.97kg shells, 1912 Model
     Breech loading guns in deck mounts with hoists
     on centreline ends, evenly spread
      2 - 2.56" / 65.0 mm guns in single mounts, 8.38lbs / 3.80kg shells, 1912 Model
     Anti-aircraft guns in deck mounts
     on side, all amidships
      4 - 0.31" / 8.0 mm guns in single mounts, 0.02lbs / 0.01kg shells, 1912 Model
     Machine guns in deck mounts
     on side, evenly spread
   Weight of broadside 184 lbs / 84 kg
   Shells per gun, main battery: 250

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   2.95" / 75 mm   295.28 ft / 90.00 m   10.01 ft / 3.05 m
   Ends:   0.98" / 25 mm     91.86 ft / 28.00 m   10.01 ft / 3.05 m
     Main Belt covers 117 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0.98" / 25 mm   0.98" / 25 mm      0.98" / 25 mm
   2nd:   0.98" / 25 mm         -               -
   3rd:   0.39" / 10 mm         -               -

   - Armour deck: 0.98" / 25 mm, Conning tower: 2.95" / 75 mm

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 4 shafts, 28,000 shp / 20,888 Kw = 26.70 kts
   Range 11,000nm at 10.00 kts (Bunkerage = 906 tons)

Complement:
   256 - 333

Cost:
   £0.298 million / $1.192 million

Distribution of weights at normal displacement:
   Armament: 23 tons, 0.6 %
   Armour: 611 tons, 14.9 %
      - Belts: 390 tons, 9.5 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 10 tons, 0.3 %
      - Armour Deck: 195 tons, 4.7 %
      - Conning Tower: 16 tons, 0.4 %
   Machinery: 1,116 tons, 27.2 %
   Hull, fittings & equipment: 1,298 tons, 31.6 %
   Fuel, ammunition & stores: 612 tons, 14.9 %
   Miscellaneous weights: 449 tons, 10.9 %
   -100 t:  Mooring Mast
   -100 t:  Landing Pad
   -100 t:  Fire Control
   -74 t:  Weight Reserve
   -50 t:  Fuel, stores, and parts for airships
   -25 t:  Long-Range Wireless

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     4,169 lbs / 1,891 Kg = 49.8 x 5.5 " / 140 mm shells or 0.9 torpedoes
   Stability (Unstable if below 1.00): 1.09
   Metacentric height 1.6 ft / 0.5 m
   Roll period: 14.0 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.14
   Seaboat quality  (Average = 1.00): 1.31

Hull form characteristics:
   Hull has rise forward of midbreak
   Block coefficient: 0.470
   Length to Beam Ratio: 9.08 : 1
   'Natural speed' for length: 19.68 kts
   Power going to wave formation at top speed: 58 %
   Trim (Max stability = 0, Max steadiness = 100): 53
   Bow angle (Positive = bow angles forward): 10.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      23.62 ft / 7.20 m
      - Forecastle (20 %):   19.69 ft / 6.00 m
      - Mid (50 %):      19.69 ft / 6.00 m (11.81 ft / 3.60 m aft of break)
      - Quarterdeck (15 %):   11.81 ft / 3.60 m
      - Stern:      11.81 ft / 3.60 m
      - Average freeboard:   16.06 ft / 4.90 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 104.9 %
      - Above water (accommodation/working, high = better): 123.1 %
   Waterplane Area: 10,711 Square feet or 995 Square metres
   Displacement factor (Displacement / loading): 118 %
   Structure weight / hull surface area: 65 lbs/sq ft or 317 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.91
      - Longitudinal: 2.32
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is excellent
   Ship has slow, easy roll, a good, steady gun platform
   Good seaboat, rides out heavy weather easily

[P3D]

The SSZ blimps are of 2,000m3 volume not 20,000. Wikipedia has one too many zeroes. A 10,000m3 airship would be longer than the cruiser itself.

That airship is useless in any wind, although GC waters have nice weather most of the time.

[maddox]

http://en.wikipedia.org/wiki/USS_Patoka_(AO-9)

An IRL example. Pleace not the type and placement of the mast.

[The Rock Doctor]

Good pic - I'll keep that in mind for a rebuild.

As to the blimp - good to know about the volume.  I'd think that if the Brits got good service out of such craft, the Colombians could in a region with generally more pleasant weather.