Topology of non-negatively curved manifolds

We study the topology of various sphere bundles over CP2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\hbox {CP}^{2}$$\end{document} which admit a metric with non-negative sectional curvature. We then compare their diffeomorphism types with known examples of positively curved manifolds, in particular Eschenburg spaces.