Tour vouchers are valid for six months from the date of purchase and are sold on a "per person" basis. All flights depart and return to The City of Derry Airport. If voucher is cancelled due to weather restrictions, validity will be extended. Tours are conducted every Saturday and Sunday weather permitting. A weight restriction of 17 stone (trial lesson) and 21 stone (tours) per seat is enforced due to aircraft limits, please contact by telephone if over this weight.