The Luftwaffe developed masterful psychological techniques to milk Allied airmen for information.
For the American and British troops who fought their way into Germany in 1944 and 1945 it was one of the toughest and bloodiest campaigns of the war. But over forty-five thousand Allied servicemen got there first, entering Germany in the hardest way possible: bailing out of a crippled airplane at eighteen thousand feet. During the course of the war more than ten thousand RAF fliers from Bomber and Fighter Commands ended up as POWs. From 1943 to 1945 more than thirty-five thousand American pilots and aircrew joined them in Luftwaffe prisons.
Almost all the captured British and American airmen had one thing in common: they spent some time at the Luftwaffe’s Auswertestelle West (Evaluation Center West) at Oberursel, a suburban town near Frankfurt. And almost every one of them met there a suave, sympathetic Luftwaffe officer or NCO who spoke fluent English, down to the latest slang, and who already seemed to know everything about the new POW.
A downed fighter pilot would be shown a file book containing the names of his unit members, the location of his home base in England, the combat record of the unit since its arrival in the theater, even the name of the commander’s dog and the unit’s favorite English pub. The astonished airman would be told who had been transferred, who had been shot down, and who had recently arrived as a replacement. The airman might also be told of the specifics of operations that he had recently flown in.
The interrogator would then smile and say, “You see, we have spies at every base in Britain and we get a full account of everything you do.” The POW would be told that the whole process of interrogation was a mere formality, given the information the Germans already had in their possession.
Upon being shown the Luftwaffe’s extensive files on his fighter group, one captured American air corps captain recalled, “I felt shocked and sickened. It was obvious that someone in our unit was providing the Germans with detailed information about us.”
Actually, no one was. In truth the Germans were applying a masterfully honed technique of accumulating trivial details to create a “we know everything” illusion which beguiled many a captured Allied airman into letting down his guard. Using a variety of clever psychological methods—all of which were completely acceptable under the Geneva Convention rules for the treatment of prisoners—and without any coercion, threats, or force, Luftwaffe interrogators often were able to glean crucial details about Allied air operations and tactics which were then quickly passed to Luftwaffe flak and fighter commands, where the intelligence was used to help shoot down thousands more Allied aircraft.
The experts at Oberursel brought the art of interrogation to a point where many Allied airmen gave up vital information without even realizing they had been formally interrogated at all.
How the Luftwaffe pried this information out of Allied officers and NCOs—who were all trained to resist interrogation— is one of the lesser-known stories of World War II intelligence.
The POW experience of Col. Hubert Zemke of the U.S. Army Air Corps was typical. In October 1944 Zemke was arguably America’s top fighter commander in the European theater. Under his command, the 56th Fighter Group (nicknamed “Zemke’s Wolfpack”) became the scourge of the Luftwaffe’s fighter defenses, with more aerial victories than any other American fighter outfit. Zemke, with seventeen and a half aerial kills to his credit, developed a reputation as a superb combat leader who could take a struggling unit and turn it into an “ace” outfit, and transferred to take command of the 479th Fighter Group in August 1944.
With more than 450 operational sorties to his credit, Zemke was due for a rotation back to the States, but he insisted on flying just a few more missions. On October 31, 1944, his luck ran out when he flew into a thunderstorm near Hanover in Northern Germany. The storm literally ripped his rugged Mustang fighter to pieces and he found himself bailing out into fierce conditions. Zemke, badly bruised by his bailout and landing, tried to hide in the nearby woods, but was soon taken prisoner.
He was taken to a holding cell at a nearby Luftwaffe base, sent to Frankfurt by train, and finally on to Oberursel by tramcar. There, Zemke was first asked to fill out an official-looking form with the Red Cross letterhead and form number. The form had spaces for his name, rank, and serial number—all information that the Geneva Convention required him to give. But there were also spaces on the form for him to fill out his home address, his civilian profession, his unit, home base, and commanding officer. Zemke knew the rules well and wrote only the legally required information; the Luftwaffe staff kept insisting that he had not filled out the processing form correctly.
Zemke was then sent to a solitary confinement cell. Although the Geneva Convention forbade solitary confinement for more than thirty days, and the Luftwaffe administration at Oberursel followed that rule, a POW usually had no idea of how long he might be held. In solitary confinement the prisoner had only a bare room, a bed, a chamber pot, and a slot in the door where meals of soup and bread were passed to him twice a day. There were no books, no newspapers, no cigarettes, and, probably worst of all, no one to talk with. Like most POWs, Zemke spent two days in solitary before being taken into interrogation.
At the interrogation office he met Cpl. Hanns Scharff, a well-educated, jovial man in his mid-thirties. Like the other top interrogators, Scharff spoke perfect English. Scharff had acquired his language skill in South Africa, where he lived for seven years before the war managing a branch of his family’s business. He was in Germany only because he had been home on vacation in August 1939 when the war began; he had been drafted and trained as an infantryman and was on his way to the Russian front when his wife brought Scharff’s fluency in English to the attention of a Wehrmacht colonel who was an old family friend. Scharff was transferred to a translator company in Germany and eventually sent on to Oberursel in 1943, where he was expected to work in administration. However, the loss of two top interrogators in an aircraft accident propelled Scharff into the interrogation business. With his phenomenal memory and friendly nature, he soon proved that he could extract information from the most recalcitrant POW.
Zemke found it was difficult to resist Scharff’s charm. After days of solitude and discomfort, he was confronted by a friendly man in a pleasant office who knew all about him and his unit. Scharff showed Zemke his book of files and news clippings about the 56th and 478th Groups and had copies of the Stars and Stripes newspaper only three days old. Corporal Scharff knew about all the aces and commanders of the American fighter units and related intimate details about the bases in England that they flew from. Scharff showed a good deal of sympathy for Zemke’s plight when Zemke complained of his stiffness and bruises from bailing out—and it wasn’t all phony sympathy. Scharff promised to get Zemke to a doctor and made good on his word, walking with Zemke the half-mile to nearby Hohemark Hospital, which had been commandeered by the Luftwaffe for the treatment of injured airmen. After being treated for his injuries, which turned out not to be serious, Zemke was invited to a good dinner with Scharff and the hospital staff.
Scharff was a superb conversationalist and took every opportunity to talk to Zemke—waiting at the hospital, walking back from dinner. It was just one of many convivial social occasions that followed. Zemke, of course, knew what Scharff was up to and would change the subject when the conversation got around to air force matters. Scharff, for his part, did not pressure or threaten Zemke. He just kept talking. After eight days at the Evaluation Center, Zemke was sent on to a regular POW camp.
“There is no doubt in my mind that he did extract something from me,” Zemke admitted later, “but I haven’t the slightest idea what. If you talked to him about the weather or anything else, he no doubt could get some information or confirmation from it. He reminded me of the typical American insurance salesman who left you with a $10,000 insurance policy after getting his foot in the door. Though he never seemed to press for information, he’d pop an innocent remark out of the blue, making me think twice.”
The Germans themselves called their interrogation method the “psychological approach,” as it was geared to exploit the fundamental human need to talk, to be understood, and to be treated with respect. Zemke experienced the German system when it was operating at the peak of its effectiveness. It had not been that way at the beginning. In fact, the Luftwaffe developed its elaborate interrogation and analysis system only after considerable trial and error and not a few missteps.
The Luftwaffe Evaluation Center West was established on the grounds of a small agricultural school and experimental farm in the Frankfurt suburbs in December 1939. The camp slowly grew with the addition of buildings. Since many prisoners were likely to be wounded, the Luftwaffe appropriated a section of the nearby Hohemark Hospital for use for the prisoners. By the height of its operations in 1943–1944 the camp would grow to hold several hundred POWs at once, with a staff of more than three hundred German guards and administrators, of whom sixty were interrogation personnel. From the start, the Evaluation Center was meant only as a holding center for airmen POWs to be processed and interrogated and then passed on to regular POW camps.
Before the outbreak of World War II the Luftwaffe had established a large signals intelligence service and also had a well-developed photo intelligence branch. Luftwaffe attachés in Western nations had collected a vast amount of open source material on aviation technology and sent it to the Luftwaffe’s general staff. The Luftwaffe’s Air Technical Intelligence Branch had officers in the field and a research center in Germany where downed or captured enemy aircraft were carefully examined.
But the prewar Luftwaffe had expected future wars to be quick campaigns, over in a matter of weeks: by the time enemy POWs were processed, the campaign would be over. So the Luftwaffe began the war without a group of specialist interrogators. But once the Battle of Britain showed the Germans they were facing a long war, they were forced to catch up quickly.
The early German attempts to glean information from captured Allied airmen from 1939 to 1941 were characteristically clumsy, brutal, and ineffective. Prisoners were handled roughly and threatened with some torture, although outright torture was not applied for fear of reprisals against German airmen. Hypnosis was tried, as well as drugs. None of these methods yielded much information.
Things changed in 1941 when a famous Luftwaffe airman, Capt. Franz von Werra, toured Germany’s POW centers. Von Werra was a German fighter pilot shot down over England in September 1940, at the height of the Battle of Britain. Von Werra became a POW, was interrogated in Britain, and eventually sent to a POW camp in Canada. In January 1941 von Werra pulled off a dramatic escape and made it to the then-neutral United States. From there he traveled to Mexico and made his way back to Germany in April 1941.
Having gone through the British interrogation system, von Werra was ordered to examine the German system and compare the two. Von Werra visited the Luftwaffe’s center at Oberursel and was not impressed. “I would rather be interrogated by half a dozen German inquisitors,” he reported to Reichsmarschall Hermann Göring, the Luftwaffe’s commander, “than by one RAF expert.”
Von Werra pointed out that the RAF had a highly sophisticated approach to prisoner interrogation that played on the prisoner’s psychological needs. First, the confusion and disorientation of the POW was exploited. During the initial processing RAF experts would carefully observe each prisoner and decide which ones were most vulnerable and likely to talk. After isolating him from human contact for a couple of days RAF interrogators would provide a kind and sympathetic ear as they used every opportunity to engage the prisoner in conversation. After winning some measure of trust, the POW’s reticence would likely drop and he would usually let out valuable bits and pieces of information during the course of an afternoon’s pleasant conversation over tea or beer. Von Werra told Göring that the British psychological approach was almost impossible to resist. Without any intention of betraying his country, a captured airman would inadvertently give up vital information.
After von Werra’s analysis, the Luftwaffe selected a small corps of expert interrogators. The first requirement was close-to-perfect fluency in English. The best English speakers were found among Germans who had lived in English-speaking countries: Scharff’s deputy, Sgt. Otto Engelhardt, was known as “Canadian Wild Bill” for the years that he had spent in Canada. Lt. Ulrich Hausmann, a specialist in interrogating bomber crewmen, had been an English literature professor in civilian life, and had spent considerable time in Britain.
Another requirement was an empathetic nature. An interrogator with a phony personality and unsympathetic manner would not earn the trust of the prisoner. In fact, several top interrogators at Oberursel were so well known for their friendly manner with the prisoners and their solicitude for the prisoner’s welfare that they came under suspicion from the Gestapo as possible Allied spies.
Finally, a good interrogator had to have a phenomenal memory. Writing down notes while talking with the POW would remind the airman that he was being interrogated. Instead, a good interrogator would talk to the prisoner, sometimes for hours, and afterwards recall important details from the conversation while writing his interrogation report.
There was no formal training; the art of interrogation was learned on the job. As the system evolved from 1942 on, the Luftwaffe found that some questioners were more successful than others. These men, regardless of rank, were assigned as lead interrogators who would interview the toughest cases and those most likely to have useful information. By 1943 the interrogators were split into specialist sections, with some specializing in downed fighter pilots, others in bomber crewmen.
To help buttress the “we know everything” illusion that was vital to the Germans’ technique, a huge amount of intelligence was gathered from other sources. The wreckage of every Allied aircraft shot down over Germany or Axis territory was carefully examined for papers, letters, and any other information. The aircraft wreckage was matched with the records of the Luftwaffe flak and fighter units to determine the circumstances of its loss. This information was sent daily to the Oberursel analysis section, which would try to match the airman POW with the downed aircraft. Once the aircraft and airman were identified as belonging to a specific unit, the basis for the interrogation became easy. Luftwaffe signals intelligence, usually young women who spoke good English, listened to the constant radio chatter of American and British air units over Britain. By late 1943 the Luftwaffe had pieced together a remarkably accurate order of battle for the U.S. Army Air Forces in Britain— complete with unit stations and call signs.
The airmen, especially the Americans, were also notoriously bad at the basics of operational security. Against all regulations, bomber crewmen and fighter pilots would bring personal letters, unit photos, and even operations orders with them into combat. Much of this survived when the aircraft was shot down and information from such sources formed the basis of the squadron and group books kept by the Oberursel analysts. In addition to such information, Luftwaffe intelligence was able to get copies of the Stars and Stripes, the U.S. Army newspaper, and British newspapers through neutral embassies in Britain. The Stars and Stripes was an especially good source of information because it regularly featured stories and photos of American air units and their exploits.
The main interest of the Luftwaffe interrogators was the latest developments in Allied tactics and equipment: radar bandwidths used by British and American bombers on their targeting equipment, the exact range and capabilities of escort fighters, and other technical details that, though small, could translate into effective countermeasures.
Captured Allied pilots and aircrew might not be privy to any grand strategic plans, but they did know their equipment and its strengths and weaknesses. An American bomber crewman captured in one of the first American raids in Europe told his Luftwaffe interrogators that the attack they feared most was high and from the front because only the two guns of the B-17’s top turret could be brought to bear against it. The Luftwaffe immediately told its fighter units to employ the “twelve o’clock high” attack against the American bombers.
Almost every day such vital tips flowed from the Oberursel interrogators to the Luftwaffe’s air defense commands, and this excellent tactical intelligence helped the Luftwaffe to shoot down thousands of British and American aircraft over Europe. A typical conversation between an interrogator and a captured American fighter pilot in early 1944 might start with the German relating the unit’s home base and mission order and course heading. He would then tell him the details of the engagement from the point of view of the German unit that had shot him down. As the German got the American to tell his story it would go something like this:
AMERICAN: That’s right. We took off from our base and climbed to altitude for our escort mission. We dropped our tanks at the Dutch border and five minutes later ran into a flight of Fw 190s.
GERMAN: Our fighter group reported that they came to you from the north and that you had the height advantage. Our fighter unit reported that you got three Fw 190s in the first pass but then another group of Me 109s joined in.
AMERICAN: We mixed it up, I got an unlucky hit in the engine…
The conversation might go on for an hour as the American pilot finally had another airman to tell his story to. Although the German interrogator had not asked any specific questions of the American, he had just learned the exact range of the new P-47 drop tanks. The Luftwaffe’s Home Defense Command now knew exactly when escorting American P-47s would be likely to turn back or turn over their escort duties to longer-ranged P-51s or P-38s. This was the most vulnerable moment for the heavy bombers because fighter units often missed their rendezvous point or were late to arrive—leaving the bombers without an escort for a while and giving the Luftwaffe fighters better attack odds.
At the end of the war, U.S. Army Air Forces intelligence carefully studied the interrogation pro- gram at Oberursel. A November 1945 report noted that the German interrogation system had adhered to the Geneva Convention rules: although in a few cases Luftwaffe interrogators had crossed the line and slapped prisoners, or threatened them with force, the final American assessment noted that such behavior was an exception to the Luftwaffe’s standard procedures and was not condoned by the center’s commanders.
The American analysts saw so many valuable lessons in the German methods that Corporal Scharff and his fellow interrogators were invited to lecture American intelligence officers on the techniques that had pried so much valuable information from Allied airmen. Because the German “psychological approach” was based on universal human needs—chiefly the need to talk to a sympathetic listener after a traumatic experience, like being shot down and taken prisoner—its effectiveness did not end with the end of World War II.
Originally published in the March 2008 issue of World War II magazine. To subscribe, click here.