Thanks, David!Sean, from available references, this is the best I can make out of
Gneisenau's enlarged 1942 hangar with any confidence. The rendering shows two views, one of the hangar with open doors and a cylinder representing the catapult pedestal which is
inside the hangar, and the other view with closed doors. As you can see, it is very different than
Scharnhorst's hangar.
Scharnhorst, as you know, had a rooftop catapult and rooftop sliding doors.
Gneisenau could launch aircraft from
within the hangar.
Attachment:
Gneisenau Hangar 1942.a.jpg [ 125.17 KiB | Viewed 5997 times ]
In addition to identifying and modeling features and details of the hangar, there is also a new, large, multi-level boxy structure built aft on top of the hangar. Some photos show a cylindrical tub on top (Cerberus), while other photos show just a splinter shield (wreck photos). The shape, size, position and footprint of this structure is very difficult to determine from photos. The structure does appear on the original builders' plans for the ship's planned 1943 reconstruction but not clearly (Breyer, 26-27 - see cropped, reduced image below). The aft end of the structure is probably flush with the hangar.
No references I have access to show the hangar interior, which plans show could hold two Arado aircraft, one on the catapult and a second stowed aft and above. Exactly how the second aircraft was stowed is a mystery. A third aircraft could be stowed on the roof, but not launched from there. The catapult and pedestal type and configuration are not discernible from available references. We could assume that is was identical to the type previously fit, and may have been the very same catapult, simply relocated to the hangar during hangar construction at Brest.
Rooftop details are unknown but rooftop tracks of some kind appear in the builder's plans, probably for an aircraft stowage cradle.
Hopefully better references will be made available and both the hangar and boxy structure can be modeled and detailed accurately for 3D-printing or scratch-building.
Any help is hugely appreciated.