Abstarct: A reconfigurable antenna is designed to use in aircraft’s communications in a frequency band vhf / uhf / L- band. The purpose of this design is to minimize the size of the antenna to the extent possible and also to enhance the bandwidth of the antenna. Also to improve the VSWR of the antenna after size reduction we used a semi-DGS Technique. The proposed antenna is fabricated on FR4 substrate with dielectric constant 4.4 and thickness of 3.2mm. One PIN diode is used for reconfiguration capability of antenna. When the PIN-diode is on (on state) the frequency covering band of the antenna is 30-230 MHz with gain 1.5 dBi and when the diode is off (off state) it is 430-1560 MHz, with Gain 3 dBi. The VSWR in all bandwidth is less than two. The measurement results shows a good agreement with simulation results that is obtained with fullwave software CST.