Continuity mistake: After Caparzo has died from the sniper bullet, when Miller's men are grouped around Caparzo's body, Horvath is holding his gun in his right hand pointing it to the ground with his left arm by his side, but in the following shot, when Miller walks up, he is holding his weapon at waist height. (00:54:25)
Continuity mistake: When Miller has just explained to Ryan that his comrades came to take him back, Miller talks to Horvath alone. While Horvath is talking over his shoulder, you clearly see him moving his hands in the next shot, from an angle just past Miller, his hands are held tight to his gun. (01:48:40)
Continuity mistake: When Upham is hiding behind a cow while his squad rushes the communication tower/bunker, he uses a sniper scope to see his squad mates. Upham holds the scope differently every time. The two knobs would first be at north/west, and the next shot would be south/east. This will change several times until Captain Miller tells him to get the gear. (01:24:20)
Continuity mistake: Near the start, when Miller's men are walking through a field, and Jackson is talking about him and his rifle, in the background Caparzo has a cigarette in his mouth, but in the following shot it is not in his mouth or hands, then it's back in his mouth again. (00:42:40)
Continuity mistake: When Miller is shocked, we see him in a close up with his hair slicked into a point on his forehead. Camera shows a few people taking shelter under a tank trap and back to Miller. In this shot, his hair is arranged completely differently. He didn't touch it himself, as he is supporting himself on a tank trap with one hand and holding his helmet in his second hand. (00:09:15)
Continuity mistake: At the start we see a close up of Ryan's face and in the background is a couple walking away. The bloke has a blue baseball cap on and dark shirt while the woman has got a light blue top and what appears to be a cream coloured skirt on. The camera then shows Ryan back as he is walking and now this couple are in front of Ryan about to walk past him. (00:01:15)
Revealing mistake: During the battle of Ramelle, when two men of the 101st prepare to firebomb a Marder tank destroyer from above, one of its German crew is looking up, spotting them. For that instant, you can see the pasty fireproof mask covering the German's face. (02:15:34)
Answer: These were barrage balloons, commonly used during the war. They are used to stop low level bombing and low level fly bys by enemy fighter planes. The cables attached to the balloons are designed to cut through the wings of the aircraft and to bring them down, so any pilot would have to fly above them, and the balloons would also restrict the view from above.