The maximum bank angle for a normal category aircraft is 60deg at 2G's. The formula for turn radius is
R(ft) = V(ft/sec)^2
-------------
G(ft/sec)*tan(bank)
given
V=168900(ft/sec) = 1000kt
G=32.2(ft/sec)
tan(bank) = .32(60deg)
R=(1690^2) / (32.2 * .320) = 27183(ft)
52.4mi