The goal of the recently approved space-based LARES mission is to measure the general relativistic Lense-Thirring effect in the gravitational field of the spinning Earth at a repeatedly claimed \approx 1 \% accuracy by combining its node \Omega with those of the existing LAGEOS and LAGEOS II laser-ranged satellites .
In this paper we show that , in view of the lower altitude of LARES ( h = 1450 km ) with respect to LAGEOS and LAGEOS II ( h \simeq 6000 km ) , the cross-coupling between the effect of the atmospheric drag , both neutral and charged , on the inclination of LARES and its classical node precession due to the Earth ’ s oblateness may induce a 3 - 9 \% year ^ { -1 } systematic bias on the total relativistic precession .
Since its extraction from the data will take about 5 - 10 years , such a perturbing effect may degrade the total accuracy of the test , especially in view of the large uncertainties in modeling the drag force .