John,

Dutch language:

1) Laatste melding : gisteren U 489 uit zicht na duik.
"Last message: the day after U 489 was out of sight after diving."
2) Verhinderen uitbraak geallieerde schepen uit Goteborg.
"Prevent breakout Allied ships from Goteborg."

Could find NO other information regarding the loss of U 857 and U 879 - the report of a direct attack by a USN blimp(s) on 18.04.45.

The possibility exists that the "blimp" episode relates to the sinking of U 853 6 May, 1945. Excerpt from Patersons "Black Flag" Page 7 follows:

....destroyed U853. Amidst the turbid water were various bits of debris that had floated to the surface, including a pillow, escape gear, a lifejacket, and a U-boat officer's peaked cap.

As dawn broke, two US Navy K-Class blimps from Lakehurst, New Jersey (K16 and K58), joined the attack. They located a large oil slick and marked the U-boat's suspected location with smoke and dye markers. K16 obtained a firm MAD (Magnetic Anomaly Detector) contact on what was, in all likelihood, the hull of a destroyed U-boat. USS Atherton, Ericsson and Moberley mounted further hedgehog and depth-charge attacks which brought further wreckage to the surface: the boat's chart table, oilskins, cork and a life raft. The final nail in U853's battered coffin was delivered by the blimps, which also attacked with 7.2m rockets. Finally, U853 was declared as confirmed sunk, with USS Atherton and Moberly receiving joint credit for the destruction, and both returning to port with brooms attached to their mastheads, an international naval symbol for a 'clean sweep'......

The "missing-loss" dates were determined by the attampts at radio contact - first contact = 1 star, 2nd contact = 2 stars. I cannot remember the exact criteria (how many days from last contact to definitely listed as lost) - "Vermisst ein Stern" (missing, one star) was missing, one star. 2 stars was "Vermisst zwei Stern" (missing, two stars),boat listed as "lost" (hard evidence). I have a reference here which explains this in greater detail, but can't remember which one.....

-- Regards,
Ken Deshaies
Newton, New Hampshire