IOS 8.1 enable gps in airplane mode

[dwschoon]

I have an old iphone 5 jailbroken on 8.1. I don't use the cellular functionality. I want to use it as a back country gps, but the battery drains rapidly searching for a tower unless it is in airplane mode. The problem is, airplane mode disables the gps along with the cell radio. I have tried pulling the sim, as well as enabling the sim pin, neither of these prevent the phone from searching for a tower. In 8.3, airplane mode does not disable the gps with the cell radio, so there is a way in the software to do it. Is there a tweak in cydia, or a hack somewhere that will help me? I don't want to have to update and lose the jailbreak.