WI Graf Zeppelin was completed?

@NOMISYRRUC Interesting in that table is the Graf Zeppelin is among the largest of the carriers, only beaten/rivalled by the Essexs, Shokakus, Ark Royal and Eagle. So the Germans, with no experience in building carriers, thought it was a good idea to start with the biggest possible. That's a bit like a starting architect planning the Empire State Building as his first project.
Plus no experienced deck crew. That's what annoys me about any thread that has the Germans building carriers and then being super-skilled with using them. It can take years to train a carrier deck crew just to adequacy. The RN, USN and IJN all managed it - after several decades of practice. You can't wave a magic wand and have an instant highly professional carrier crew.
 
Plus no experienced deck crew. That's what annoys me about any thread that has the Germans building carriers and then being super-skilled with using them. It can take years to train a carrier deck crew just to adequacy. The RN, USN and IJN all managed it - after several decades of practice. You can't wave a magic wand and have an instant highly professional carrier crew.
Indeed. Which is why I like the scenario I quoted in post #4 very much.
 
@NOMISYRRUC Interesting in that table is the Graf Zeppelin is among the largest of the carriers, only beaten/rivalled by the Essexes, Shokakus, Ark Royal and Eagle. So the Germans, with no experience in building carriers, thought it was a good idea to start with the biggest possible. That's a bit like a starting architect planning the Empire State Building as his first project.
I was surprised by how close Graff Zeppelin and Essex were in terms of waterline length and beam. However, according to Whitley in German Capital Ships of World War Two it was intended to be a much smaller ship.

The chapter on the aircraft carriers says that the design of what became Graff Zeppelin began in March 1934 one year before the denunciation of the Treaty of Versailles and 15 months before the Anglo-German Naval Agreement. The intention was to order one ship in October 1935 as part of the 1935 Programme. The basic requirements were:
  1. Theatre of operations - Atlantic and North Sea
  2. About 15,000 tonnes displacement
  3. Speed 33 knots (continuous)
  4. Armament nine 15cm or six 20.3 cm guns with a strong flak outfit
  5. Endurance 12,000nm
  6. Cruiser protection
  7. 60 aircraft, a third of them with folding wings
  8. Two catapults
  9. The Air Ministry had indicated a minimum flight deck length of 180m.
It also said that the design team had obtained technical details of Lexington and was using Courageous as a useful starting point. It also said that improving relations with Japan allowed them to send a team to inspect Akagi and as a result of that visit numerous alterations were made including adding a third lift and an extension of the flight deck. The sentence before that says that they believed that a larger number of smaller ships would have been better, but the needs of the aircraft complement and and minimum flight deck length pushed the displacement inexorably upwards.

The above aircraft carriers were all bigger than the 15,000 tonne ship planned in March 1934. In the case of Akagi and Lexington considerably so. Therefore, the size of the ships that they were using as a guide (in addition to the aircraft and flight deck length requirements) may have resulted in Germany's "first time" design being so large.

OTOH (if the Langley and Hosho are ignored) the first American and Japanese aircraft carriers were their capital ship conversions. These were even larger than Graff Zeppelin. Although I admit that they wouldn't have displaced that much had they been designed as aircraft carriers from the keel up. Plus 2 of the 4 British prototypes (Eagle and Furious after her 1921-25 rebuild) displaced over 20,000 tons. Therefore, the early American, British and Japanese aircraft carriers were also on an "Empire State" scale.

I should also add that the aircraft carrier quota of 135,000 ton of aircraft carriers for the British Empire and the 27,000 ton limit for individual aircraft carriers in the Washington Treaty was because the Royal Navy wanted five 27,000 ton aircraft carriers in the early 1920s but as the decade progresses they found that they could design smaller ships with the characteristics they wanted which is partially why the abortive 1931 Carrier and Ark Royal displaced 22,000 tons. Therefore, Graff Zeppelin's size could have been the result of inexperience rather than any deliberate intention to build the largest ship possible.

Having mentioned Langley and Hosho the Reichsmarine should have had a contingency plan for a quick and simple merchant ship conversion when political conditions allowed. This would have been along the lines of their OTL contingency plan to build U-boats when political conditions allowed. The plan should have been implemented as soon as possible after the Nazis came to power (January 1933). The purpose of the ship would be to get some practical experience that could be incorporated into the design of later ships and to act as a training ship for the aircrew and ground crew of the later ships.

According to Whitley (again) the Reichsmarine laid the foundations of a naval air arm in October 1928 when it obtained government approval for a few seaplanes for "experimental" purposes. The excuse for this was the fact that the Treaty of Versailles allowed the Reichsmarine to retain anti-aircraft guns. This was interpreted as also permitting aircraft to tow the necessary targets! (Whitley's exclamation mark.) In this way an organisation known as "Air Services Incorporated" was formed as a cloak for its illegal activities in the fleet. Whitley finished by saying that although eventually killed off with the advent of Herman Goering and his "everything that flies belongs to me" attitude, this service did constitute the basis of a naval air arm.

So based on the last paragraph I think October 1928 is a plausible POD for the scheme to convert a suitable merchant ship into an experimental aircraft carrier.
 
Last edited:
I've been doing some arithmetic and it seems that the number of aircraft that Graff Zeppelin could operate has been underestimated.

According to Whitley in German Capital Ships of World War Two the Graff Zeppelins had two hangars. The upper hangar was 185 x 24 metres and the lower hangar was 172 x 24 metres. The upper hangar had a clearance of 5.70 metres and the lower hangar had a clearance of 5.36 metres.

According to http://www.german-navy.de/kriegsmarine/aviation/carrierbased/index.html a Bf109T was 8.76 metres long and had a span of 11.08 metres. As far as I can ascertain from my internet searches the wings didn't fold, but they could, however, be detached from the fuselage for transport purposes, as in every version of the Bf 109. (Source: https://www.nevingtonwarmuseum.com/me-109-t.html)

That's 38 Bf109T two-abreast in the upper hangar and 36 Bf109T two-abreast in the lower hanger for a total of 74 with a clearance of 60 centimetres between each aircraft.

I think they'd actually embark 72 Bf 109Ts organised into 8 squadrons of 9 or 6 squadrons of 12 plus some aircraft with their wings removed as spares.
According to Smith & Kay on Page 478 of Putnam's German Aircraft of the Second World War the Bf109T had manually folding outer wings and according to Whitley on Page 81 of German Capital Ships of World War Two the Bf109T had folding wings that hinged just outboard of the gun bays.

Unfortunately, I can't find a source that says what the folded wingspan was or that has a line drawing of the aircraft with its wings folded that I can measure. So I've measured the line drawing of the Bf109T (https://upload.wikimedia.org/wikipedia/commons/d/d0/Bf109T_3Seiten_neu.jpg) on Wikipaedia and my guess is that folding reduces the wingspan from 11.08 metres to 5.34 metres which would allow four-abreast stowage in Graff Zeppelin's 24 metre wide hangars. That increases the hangar capacity to 148 aircraft. Except that the practical limit would be much lower due to the amount of fuel, ordnance, spare parts, accommodation for maintenance crew and the stores required for the maintenance crew.

Friedman on Page 394 of U.S. Aircraft Carriers lists the similarly sized Essex at 91 aircraft consisting of 36 F6F-3, 37 SB2C and 18 TBF at December 1942. Some of that would have been in a deck park, but Graff Zeppelin's hangars were longer and wider so I think it could comfortably accommodate 90 Bf109Ts in the hangar with space for some disassembled aircraft as spares.
 
Last edited:
According to Smith & Kay on Page 478 of Putnam's German Aircraft of the Second World War the Bf109T had manually folding outer wings and according to Whitley on Page 81 of German Capital Ships of World War Two the Bf109T had folding wings that hinged just outboard of the gun bays.

Unfortunately, I can't find a source that says what the folded wingspan was or that has a line drawing of the aircraft with its wings folded that I can measure. So I've measured the line drawing of the Bf109T (https://upload.wikimedia.org/wikipedia/commons/d/d0/Bf109T_3Seiten_neu.jpg) on Wikipaedia and my guess is that folding reduces the wingspan from 11.08 metres to 5.34 metres which would allow four-abreast stowage in Graff Zeppelin's 24 metre wide hangars. That increases the hangar capacity to 148 aircraft. Except that the practical limit would be much lower due to the amount of fuel, ordnance, spare parts, accommodation for maintenance crew and the stores required for the maintenance crew.

Friedman on Page 394 of U.S. Aircraft Carriers lists the similarly sized Essex at 91 aircraft consisting of 36 F6F-3, 37 SB2C and 18 TBF at December 1942. Some of that would have been in a deck park, but Graff Zeppelin's hangars were longer and wider so I think it could comfortably accommodate 90 Bf109Ts in the hangar with space for some disassembled aircraft as spares.
Same objections as before. Plus one has not accounted for the differences among the sources used.
 
According to http://www.german-navy.de/kriegsmarine/aviation/carrierbased/index.html a Fi 167 was 11.40 metres long and had a span of 13.50 metres.

The wings did fold, but I've been unable to find a source that includes the folding wingspan, but after looking at photographs of Fi 167s with their wings folded and measuring the line drawings my guess is that it's 5.15 metres which is narrow enough for 4 abreast.

After allowing a 60 centimetre clearance between the aircraft the upper hangar can accommodate 60 Fi 167s in 4 rows of 15 and the lower hangar 56 in 4 frows of 14. That's a grand total of 116 aircraft.

According to http://www.german-navy.de/kriegsmarine/aviation/carrierbased/index.html a Ju 87 was 11.50 metres long and had a span of 13.80 metres.

The wings did fold, but I've been unable to find a source that includes the folding wingspan, but after looking at photographs of Ju 87s with their wings folded and measuring the line drawings my guess is that it's 4.93 metres which is narrow enough for 4 abreast.

After allowing a 60 centimetre clearance between the aircraft the upper hangar can accommodate 60 Ju 87s in 4 rows of 15 and the lower hangar 56 in 4 frows of 14. That's a grand total of 116 aircraft.

I've calculated that the hangars could accommodate 48 Fi 167s or 48 Ju 87s plus 44 Bf 109Ts for a total of 92 aircraft but I think 48 bombers and 24 fighters for a total of 72 in 6 squadrons of 12 would be more realistic.
Based on what I've written in Post 84 about the Bf109Ts folded wingspan Graff Zeppelins hangars could have accommodated the following aircraft in rows of 4 and still have had about a third of their length to spare.
  • 36 Bf109 and 54 Ju87 - Total 90
  • 28 Bf109 and 56 Ju87 - Total 84
  • 24 Bf109 and 60 Ju87 - Total 84
The Fi167 was 10 cm shorter than the Ju87 and could also be stored 4 abreast so a one-to-one substitution is feasible.
 
Based on what I've written in Post 84 about the Bf109Ts folded wingspan Graff Zeppelins hangars could have accommodated the following aircraft in rows of 4 and still have had about a third of their length to spare.
  • 36 Bf109 and 54 Ju87 - Total 90
  • 28 Bf109 and 56 Ju87 - Total 84
  • 24 Bf109 and 60 Ju87 - Total 84
The Fi167 was 10 cm shorter than the Ju87 and could also be stored 4 abreast so a one-to-one substitution is feasible.
I’d recommend applying these calculations to Wasp and Victorious , looking at numbers you come out with, comparing that to early war actual air groups for these, and asking yourself why they differ.
Answer is you’re calculating a theoretical maximum without properly accounting for operational realities.
 
HOw's this for a different option:

She's complete in late 1940, finishes working up in the Baltic by June, 1941, then is sunk by a Soviet Submarine operating out of Leningrad in July 1941.
 
HOw's this for a different option:

She's complete in late 1940, finishes working up in the Baltic by June, 1941, then is sunk by a Soviet Submarine operating out of Leningrad in July 1941.
Collides with Tirpitz off Aaland in Sept 41 and is run aground to prevent being sunk breaking her back ;)
 
I’d recommend applying these calculations to Wasp and Victorious , looking at numbers you come out with, comparing that to early war actual air groups for these, and asking yourself why they differ. Answer is you’re calculating a theoretical maximum without properly accounting for operational realities.
I won't follow you recommendation because... One I don't have time. Two I'm not saying how many aircraft Graff Zeppelin would have operated. I'm saying how many aircraft it could have been operated because the number of aircraft that the reference books quote seem too low for a ship of this size.

However, the theoretical capacity of Graff Zeppelin will be a lot larger than the theoretical capacity of the ships that you mentioned because it was considerably larger. See below...

Comparison of Aircraft Carriers.png

 
I won't follow you recommendation because... One I don't have time. Two I'm not saying how many aircraft Graff Zeppelin would have operated. I'm saying how many aircraft it could have been operated because the number of aircraft that the reference books quote seem too low for a ship of this size.

However, the theoretical capacity of Graff Zeppelin will be a lot larger than the theoretical capacity of the ships that you mentioned because it was considerably larger. See below...

Why do the Germans of the time, not you, not me, not others cited though this guy is my standard reference in my library;

Chesneau, Roger (1998). Aircraft Carriers of the World, 1914 to the Present An Illustrated Encyclopedia. London: Brockhampton Press. p. 288.

list her capacity as no more than 45 aircraft or 6 less birds than the Italian flattop, Aquila? Tricing? Hanger congestion? Do we have a good internal frame plan for those hangers? How about photographs. I can get them for Ranger and Wasp. Show how the Americans jammed in 70 birds on each of them.
 

Coulsdon Eagle

Monthly Donor
Based on what I've written in Post 84 about the Bf109Ts folded wingspan Graff Zeppelins hangars could have accommodated the following aircraft in rows of 4 and still have had about a third of their length to spare.
  • 36 Bf109 and 54 Ju87 - Total 90
  • 28 Bf109 and 56 Ju87 - Total 84
  • 24 Bf109 and 60 Ju87 - Total 84
The Fi167 was 10 cm shorter than the Ju87 and could also be stored 4 abreast so a one-to-one substitution is feasible.

I’d recommend applying these calculations to Wasp and Victorious , looking at numbers you come out with, comparing that to early war actual air groups for these, and asking yourself why they differ.
Answer is you’re calculating a theoretical maximum without properly accounting for operational realities.
NOMISYRRUC (is that a Simon who loves curry?)

A theoretical maximum is of no use. A usable maximum - and, given the plans for GZ, you are overstating the hangar space - is what would be sought. No point having a plane on board if it cannot reach the elevators.
 
I won't follow you recommendation because... One I don't have time. Two I'm not saying how many aircraft Graff Zeppelin would have operated. I'm saying how many aircraft it could have been operated because the number of aircraft that the reference books quote seem too low for a ship of this size.

However, the theoretical capacity of Graff Zeppelin will be a lot larger than the theoretical capacity of the ships that you mentioned because it was considerably larger. See below...

Okay, given that you’re stating that Graf Zep could have operated more aircraft than has previously been accepted I just thought it would be a good way for you to check your methodology for flaws. It’s the sort of cross check I do all the time at work, hence it immediately springing to mind. If I’ve got a set of calculations which gives me a prediction that doesn’t “smell” right, I run the calculations against a dataset where I know the actual outcome. If my calculated data doesn’t match the actual data I know my model is wrong- either a missing variable, an incorrect variable, or a faulty formula.
 
I guess the pickets will be noticed by the reconnaissance flights as well, and possibly raise the question what they are doing.

I'd think the radar emissions from the pickets would be the noticeable thing first. To keep the Brits guessing you'd want to switch things around a bit, times, localities, patrol patterns. But, that can only go so far if you want to accumulate sufficient data on British flights over the N Sea.
 
The only example of aircraft carriers being used to attack merchant shipping that I can think of is the merchant shipping that the Japanese sank in the vicinity of Ceylon during the Indian Ocean raid.

There were the early 1942 raids of the USN on assorted Japanese islands. Those damaged/sank some of the cargo ships present in the atoll anchorages. The Lae raid in March 1942 was aimed at a Japanese Army convoy bringing the follow up to the initial 17th Army landings on New Guniea. Aside from the ships sunk the remainder scattered still loaded & the deliveries were delayed days or weeks as the cargo ships were returned in smaller groups.

Earlier February the Lexington had attempted a raid on the harbor at Rabaul. It was aborted, but a attack by 18 Japanese bombers suffered 80%+ losses.

The Japanese supply convoys to to Guadalcanal were attacked multiple times by the US carrier TF, supplementing the frequent attacks from the Marine/USN airwing on Henderson Field.

There were a few other examples from 1942. The histories of the Pacifc war have descriptions of most of them.
 
Top