Arromanches

Intercepted diplomatic signals ("MAGIC" decrypts) from the Japanese Enbassy in Stockholm in December 1944 take it out of the realm of fiction:

Several of these Gold shipments were mentioned in ULTRA decrypts of signals from the Japanese Embassy in Berlin and were sent to fund the Embassy and it's large retinue of advisors or staff. Also to fund purchases of manufacturing rights to Nazi technology. Some of the Gold appears to have been aboard I-30 referred to as MOMI-1 in ULTRA traffic. That wreck was quietly salvaged some years ago north of Sumatra. Of equal interest was that before France fell, French warships evacuated 1,200 tons of Gold bullion to Dakar and from there to Saigon where it was buried outside the city. When French Indochina (Vietnam) was invaded by Japan they recovered that Gold and sequestered it in hiding places across the Philippines. With help of the Japanese royal family after the war, the CIA recovered most of the hidden gold and shared it 50:50 with the Japanese royal family. The CIA used it's share to create a fund for black ops which was beyond the scruitiny of Capitol Hill.

Hi Biber In 1941 the Kreigsmarine Rear Admiral Dr Otto Haxel began experimenting imploding small silver spheres with hollow charges. He obtained implosion pressures of 200,000 atmospheres with material being slammed together at very high temperatures at 7-10 kilometres per second. The point of this was, when repeated later by Kurt Diebner at Kummersdorf in 1942 with Lithium and a Deuterium target inside the spheres it generated artificial neutrons. Nowadays we call artifical neutron radiation X-rays. The purpose of these experiments was that Dr Eric Schumann and Dr Walter Trinks developed a series of workable patents during WW2 for tactical nuclear warheads of about 1 kiloton yield. The implosion of Lithium with Deuterium acted like a spark plug to ignite sub-critical amounts of fissile uranium. The Paris cyclotron was used to obtain small amounts of highly enriched uranium during WW2. It's highly controversial and much disputed whether Nazi Germany had such weapons however there was a diplomatic signal from Japan's embassy in Stockholm in December 1944 claiming they had been used in action on the eastern front. Also the Woods memorandum in Cordell Hull's papers alerted Washington from switzerland that three nuclear tests were thought to have occured near bisingen in the Schwabian Alps during July-August 1943

Grützmacher was CIC at Penang from January 1945. Before this, he was CIC in Yokohama. There were successive different CIC at Penang: Trendtel (from Japan, but did not take over command because of a new task in Japan) Erhardt Hoppe Erhardt again (because Hoppe was despatched on U-168, but later returned to Java) Wilhelm Dommes Grützmacher Dr. Kandeler was CIC at Djakarta (Tjiang Priok) formerly Batavia. The city was renamed by the Japanese with Jakarta meaning "Victory." Keep in mind that the U-boat base at Georgetown, Penang island ceased to exist as a functional U-boat base after October 1944 when all U-boats transferred to either Djakarta or Soerabaya due to Allied submarine activity off Penang followed by aerial mining. By 1945 when Grützmacher took charge Penang's only significance was as a radio station. It was the only official Kreigsmarine base permitted within Japanese held Asia. Penang would receive and transmit messages to OKM Germany, however two small frieghters Bogota and Eritrea with radio stations were positioned to maintain contact at Djakarta and Soerebaya. Former Italian submarines UIT-24 & UIT-25 also maintained a regular cargo shuttle to Japan. Some U-boats also sailed to Kobe Japan for replacement of spent batteries. Torpedoes and spares were replenished for the flotilla with arrival of the type VIIF U-1062. The last transport U-boats to arrive (from Bordeaux France) did so in November 1944 (U-219 and U-195)

Individual U-boats when they were ordered to operate together were not addressed in signals by their numbers but rather by the surnames of their Captains. Wolfpacks were still ordered to sea in the closing months of WW2. One group of eight U-boats was ordered to attack the apporaches to New York in April 1945 with another ordered off the Azores.