During the spring of 1944, the USS Ordronaux was involved in exercises off the Maine coast when word was received that a burst radio transmission was picked up from a U-boat operating near Nova Scotia. U-856, under command of its new skipper, Ober Leutnant zur See Fritz Wittenburg, had been detected. Immediately, the destroyers: Champlin, Ordronaux, Boyle, and Nields were formed into Task Unit 27.2 and dispatched to the last known location of the U-boat. After intensive searching and working closely with planes from the escort carrier USS Croatan, contact was finally established by a TBM aircraft at 0310 hours on the morning of 7 April, 1944. It would be a long day for all involved.

The aircraft reported being fired upon and dropped several red flares to mark the sub's position for the closing destroyers. Boyle made first contact at 0610 with her sonar, dropping a series of depth charges. After 30 minutes it appeared that positive contact was in doubt. From this point until mid-afternoon, numberous box pattern searches were performed by the destroyers until Champlin reported a sound contact at 1540. By this time the recently arrived destroyer escort Huse, had established contact also. Champlin and Huse , working together, dropped a series of deep-set depth charges and the latter fired hedge-hogs. Contact was lost momentarily, then Champlin regained contact and made another depth charge run. Five minutes later, the U-856 came to the surface. The submarine immediately drew fire from the circling ships, where Champlin scored several hits including one on the conning tower, which started a furious fire. Champlin dashed in for the kill, ramming the stern of the submarine, and suffered some minor hull damage. It was now obvious that U856 was doomed as her crew took to the water. In the rough seas, the Ordronaux commenced to picking up survivors; the first of which by chance was the commander of the U-boat, Fritz Wittenburg. Lt. Dave Owen, the Ordronaux's XO remembers brandishing his .45 as Fritz was pulled aboard and the latter saying in perfect English "you won't be needing that today".

At 1723, the U-856 slipped beneath the waves for the last time. For survivors in the water they could feel the impact of the sub self-detonating as it went down. In all, the "O" rescued 17 German crewmen, with the Nields picking up another 11. Unfortunately for the Champlin, her skipper CDR John Shaffer, was fatally wounded in a freak accident when one of the ship's 20mm rounds ricocheted off the lid of an open ammo locker. Despite heroic on board surgery performed by the ship's doctor, CDR Shaffer died the following morning at 0803.

While stopping to pick up the U-boat survivors, there was apprehension on the Ordronaux's bridge about the existence of a second U-boat that had been alluded to in a previous dispatch. With that in mind, Lt. Owen, through interpreter EIYNCK, the "O's" cook, began interrogating the prisoners. Captain Wittenburg remained dutifully silent but others revealed interesting data that Dave Owen recorded in a note book. Today, Fritz concurs with an entry in the book that at one point he was at the extreme depth of 200 m (656 feet), and it was a charge going off beneath his stern that destroyed his rudders and propellers. With his aft torpedo room flooded, his only recourse was to surface and survive.

Fritz eventually wound up in a POW camp in Arizona. The events of 7 April, 1944 provided a prime example of the level of teamwork that had evolved by this time in the anti-submarine war. For the Germans it was another tragic loss of brave men dying in a branch of the naval service that would eventually suffer some 80% attrition.

The final moments of U-856 are seen from the bridge of the DE Huse.