1st Airborne Division's commanding officer, Major General Roy Urquhart, originally planned for the 2nd Battalion to lead the 1st Parachute Brigade into Arnhem to secure the road, rail and pontoon bridges over the Lower Rhine. Frost chose Major Digby Tatham-Warter's A Company to lead the battalion's march from the drop zones to the bridges, knowing him to be "a thruster if ever there was". A company was in action almost at once, ambushing a small German recce group near the drop zone. The company moved off through the woods toward the river road, with each platoon taking turns to lead. There was a brief plan to advance the platoons by jeep once out of the woods, but German forces were encountered shortly afterwards and the idea was not followed up. Grayburn had just arrived at a road junction and headed north when the men behind him came under enemy fire. After laying a smokescreen he led a charge that cleared the enemy positions. Tatham-Warter lacked confidence in the Airborne radio equipment and had trained his platoons to use bugle calls; it was with the charge that Grayburn signalled that the advance could be resumed.