Werner's field test of the tracking transceiver is both a practical demonstration of radio direction-finding and a moment when technical success collides with moral danger. In the frozen darkness near Schulpforta, Werner locates Frank Volkheimer by calculation; at the end of the search, Dr. Hauptmann points a pistol at the hidden cadet, and Werner must confront what the experiment’s language of triangles and numbers can conceal.

The test and its apparatus

At midnight, Dr. Hauptmann’s hounds run through the frozen fields beside the school, with Hauptmann following in a fur cap and Werner bringing the pair of transceivers they have tested for months. The scene begins as a field exercise, but its scale is deliberately unsettling: Hauptmann has sent Volkheimer ahead with a KX transmitter in an ammunition box and told him to broadcast steadily until he is found or the battery dies. The search area covers ten square kilometers, and even Hauptmann does not know where Volkheimer is.

Hauptmann presents the uncertainty as part of the pleasure of the exercise. He tells Werner to set up in a place with good sight lines and explains that teams would not normally know which band to search; for this first field test, however, they will use eighty meters. The distinction matters: Werner is testing not simply whether a receiver can detect a signal, but whether a team can use measurements to locate a concealed transmitter across an unfamiliar landscape.

Werner stamps no clearing into the snow himself; instead, Hauptmann makes a place to work, and Werner establishes two receiving positions two hundred meters apart. He uncoils the grounding wires, raises the aerials, switches on the equipment, and adjusts the receivers while his fingers grow numb. With the headset filling his ears with static, he increases the radio-frequency gain and adjusts the filter until both receivers pick up Volkheimer’s signal. The transmitter’s faint, repeatable ping turns the empty snowy field into a problem that can be measured.

From signal to landscape

Hauptmann insists that Werner do the calculations on the radio casing, reasoning that field teams may not have paper. Werner sketches the equation on the metal, enters the figures, and uses a slide rule supplied by Hauptmann. Within two minutes, he has a vector and a distance: two and a half kilometers. Then, with a protractor and compass, he draws the lines onto a map. The transceivers do not reveal Volkheimer directly; they give Werner bearings and distance, which he must translate into a route through the terrain.

The physical search makes that translation visible. Werner folds the map into his coat, packs the receivers, and carries one in each hand. The school and its outbuildings soon look like toys on the white plain below. He and Hauptmann descend into a ravine and climb out again, covering one kilometer and then two. The measuring instruments have sent them away from the familiar buildings and into a landscape where the only tracks are their own.

On a later climb, Werner checks the bearings again. The new triangulation places them less than half a kilometer from the earlier estimate. He packs the equipment and quickens his pace. The figures have become direction and distance, and the search now takes on the physical urgency of pursuit: the dogs sense something ahead, Hauptmann raises a hand, and Werner finally sees a man lying faceup in the snow, with the transmitter at his feet and its antenna rising into the low branches.

The human stakes of the experiment

At this close range, Hauptmann draws his pistol and tells Werner that he cannot hesitate. Volkheimer’s breath is visible in the cold as Hauptmann aims directly at him. For a long moment, Werner believes his teacher is about to shoot the cadet, and the technical exercise becomes a credible threat to a human life. The account brings back Jutta’s earlier question about whether it is right to do something merely because everyone else is doing it. Werner’s success in solving the problem has brought him to a moment in which following the exercise’s logic seems inseparable from obeying authority.

Hauptmann fires into the sky. Volkheimer drops into a squat as the dogs rush toward him, but they know him; their charge becomes play, and he throws them off as if they were housecats. The release of tension is immediate, yet the preceding danger is not erased. Werner’s heart seems to have been blown apart, while Hauptmann laughs, drinks from his flask, and passes it to him. The transceivers work, and Werner has pleased his professor, but the success has unfolded beside a drawn weapon and a moment of genuine fear.

Numbers, distance, and responsibility

Afterward, Hauptmann identifies the exercise as what they are doing “with the triangles.” Volkheimer approaches carrying the KX transmitter and rests a large mittened hand on Werner’s cap. Quietly enough that Hauptmann cannot hear, he says, “It’s only numbers.” Werner answers by imitating Hauptmann’s clipped accent: “Pure math, cadet. You have to accustom yourself to thinking that way.” The exchange links the successful method to a habit of thought. Measurement is what lets Werner find Volkheimer across the snow, but the same abstraction can make a person seem like only a position to locate.

The scene also makes the test a threshold in Werner’s experience: he thinks he has found “a way in,” and the calculations are becoming real through movement, terrain, and discovery. Yet the apparent triumph remains morally unsettled. Hauptmann’s pistol exposes the coercive possibility inside the exercise, while the “only numbers” exchange shows how Werner and Volkheimer use their teacher’s language to frame what has happened. In that tension, the field test demonstrates both the power of Werner’s technical skill and the danger of treating its human consequences as merely mathematical.