possessive with colonelle vs. colonel

[Atemp 0]

I am writing an English-speaking french male lieutenant who must address a female colonel of the US Army, but using the french idiomatic forms of the 19th century.

If she were a male colonel, I suppose that Mon Colonel would be used.

But none of my French-speaking acquaintances can say for sure whether Ma Colonelle is correct, or whether the ma would be used at all, much less Colonelle. The lieutenant in question is already taken aback by the very existence of a female officer.

The matter is complicated by the differing genders and the rank mismatch between addresser and addressee.

Thanks in advance for any offered insight!