20-9. The unit must have access to and from the DZ to recover personnel, equipment, or both, or to conduct troop movement. Drop zones with no roads leading to them or those next to a river with no bridges are examples of impeded access to areas.20-10. Air routes to and from the DZ should not conflict with other air operations or restrictive terrain, or with manmade objects such as television or radio towers. Other considerations are:No fly areas (restricted operations zones).Obstacles to the aircraft (man-made items).Terrain above the drop zone.Enemy situation.20-11. The following information provides minimum peacetime sizes when using fixed-wing and rotary- wing aircraft and must be adhered to unless a waiver is issued in writing according to service regulations. During contingency or wartime missions, DZ sizes may also be waived. However, size requirements remain a joint responsibility of the airlift commander and the Airborne commander.Note. To convert yards to meters, multiply yards times .9144 (yards x .9144). To convert meters to yards, divide meters by .9144 (meters ÷ .9144).20-12. The distance required for personnel and door bundles for GMRS/VIRS drop zones is determined by the use of the formula D=RT. The minimum size is 275 meters by 275 meters for a single shipment for USASOC and other service missions. Refer to table 20-4 for the CARP to determine size requirements for all CARP drop zones and GMRS/VIRS equipment drops.