A scheme of simplified smooth hybrid inflation is realized in the framework of supersymmetric $SU(5)$. The smooth model of hybrid inflation provides a natural solution to the monopole problem that appears in the breaking of $SU(5)$ gauge symmetry. The supergravity corrections with nonminimal Kahler potential are shown to play important role in realizing inflation with a red-tilted scalar spectral index $n_s <1$, within Plancks latest bounds. As compared to shifted model of hybrid inflation, relatively large values of the tensor-to-scalar ratio $r lesssim 0.01$ are achieved here, with nonminimal couplings $-0.05 lesssim kappa_S lesssim 0.01$ and $-1 lesssim kappa_{SS} lesssim 1$ and the gauge symmetry-breaking scale $M simeq (2.0 - 16.7) times 10^{16}$ GeV.
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