 Lieutenant @-@ Colonel Otway , who wrote an official history of the British airborne forces during World War II , stated that Operation Varsity highlighted the vulnerability of glider @-@ borne units . While they arrived in complete sub @-@ units and were able to move off more quickly than airborne troops dropped by parachute , the gliders were easy targets for anti @-@ aircraft fire and short @-@ range small @-@ arms fire once landed ; Otway concluded that in any future operations , troops dropped by parachute should secure landing zones prior to the arrival of glider @-@ borne units . Thus , by having the landings conducted during daylight to ensure greater accuracy , the Allied planners incurred a far greater casualty rate , particularly amongst the glider @-@ borne elements . The operation also suffered from poor piloting . Although the piloting was of a better quality than in the Sicilian and Normandy operations , there were still significant failures on the part of the pilots , especially when it is considered that the drop was conducted in daylight . A significant error occurred when the pilots of the transports carrying 513th Parachute Infantry Regiment dropped much of the regiment several miles from their designated drop zones , with the mis @-@ dropped units actually landing in the British landing zones . 
