The traditional airborne gravimetric data processing method, based on frequency domain filtering, does not take into account the statistical properties of measurements, such as correlations, and does not allow an easy estimation of the errors on the gravity. We therefore developed a new reduction method based on the transformation of the differential equation of the gravimeter into an integral equation. This equation is then solved through a regularized inversion in the least squares sense. We successfully applied this new method to model the medium wavelengths of the gravity field over the South-West part of the Alps with an intrinsic precision of 3 mGal. The data used were gathered with a "Lacoste & Romberg Air/Sea" gravimeter during an airborne gravimetric survey carried out in 1998 in the framework of the national research program "GéoFrance 3D".
