Wing rock phenomenon is undesired vibration in rolling angle occurring in delta wing aircraft at large angles of attack. This paper presents three versions of model refernce adaptive controllers; namely classical MRAC, s-modified MRAC and weighted s-modified MRAC to control the rolling dynamics under wing rock phenomenon with the presence of unmatched disturbance. The stability analysis of new proposed strategy for weighted s-modified MRAC has been presented. The effectiveness of the controllers is assessed in terms of their robusness under unmatched disturbance. The simulated results based on MATLAB/SIMULINK show that s-modified adaptive controller gives better robustness characteristics than classical one; as it could confine different aircraft responses within smaller bounded limits. Moreover, as compared to s-modified controller, weighted s-modified controller gives better enhancement in terms of robustness, control effort and error charcteristics.