Intruder,
While not explicitly forbidden word by word, the aircraft is NOT CERTIFIED to fly in FZRA. That is why it IS explicitly mentioned that when entering FZRA, you need to find an escape asap.
And even IF you could land safely ( although your icing equipment will not cope and in case of go-around, there exists no data for a successful aerodynamic climb), how do you think the RWY and taxiways will be like...
We ask this scenario during command upgrades to see if the future Captain can think further than his/her nose is long...