The federation has their tier 5.5 ship, why not make the K'vort, and make it Tier 5.5? the only question to me is the K'vort an escort or a cruiser? I tend to think escort. so to make it 5.5 give it a battle cloak

It's neither; it's a bird of prey.

http://www.startrek.com/database_art...s-bird-of-prey

Well no sh*t it's a Bird of Prey styled class. For one, the classic BOP most are used to are very small ships. The K'Vort is a much larger version of the BOP format. TNG is the only show that had shown these larger craft.

Well it's obvious you know that. It was a response to the OP's question whether it's cruiser or escort as indicated in the post title.

Picard: "Military log supplemental: Lt. Tasha Yar has transferred to the Enterprise-C where she has taken over tactical duties. Meanwhile our long-range sensors have picked up Klingon battlecruisers on an intercept course."
Riker: "Numer and type of ships mister Crusher."
Wesley:"Three K'vort class battlecruisers, sir".

I think that's clear enough.

In the context of the shows, which could of course not anticipate the way STO would categorize the ships, "Bird of Prey" seems to have been more of a way to define the shape and not the size and function of a ship.
For example the Bird of Prey in Star Trek 3 was called a "scout class wessel" by Chekov and "Bird of Prey" by Sulu.
While Riker also referred to one of the K'vorts in "Yesterday's Enterprise" as "Bird of Prey" during the first attack that kills Garrett while both Picard and Wes called them "battlecruisers".

As a side note: whoever wrote that entry in the "StarTrek.com" database was obviously too dumb to even count the number of ships on the picture attached to the article itself.

This could be a good way to get another type of KDF ship.

However during the Trek shows and films they created like several sizes of these Bird of Preys. This article is well written on trying to figure out all the different sizes.

http://www.ex-astris-scientia.org/articles/bop-size.htm

The K'Vort is only as big as http://www.stowiki.org/images/7/77/KDF_Size_Chart.PNG these Birds of prey, and they all function as Raiders not Cruisers.

There is a signifficant difference between two objects having the same length and having the same mass and volume.

http://img15.imageshack.us/img15/740...akvortcomp.jpg

While the Hegh'ta and the K'vort have the same length, they certainly do not have the same volume.
The K'vort is actually far more massive sine most of the size on the Hegh'ta comes from very thin pieces like the neck and the wings which are very differently proprotioned on the K'vort which has a comparatively short neck since its engineering section is much larger.
Not to mention the much larger wings and bigger command pod.

Saying two two craft have the same size due to a similarity in one dimension is like saying the Handley Page Type O is the same size and mass as the F-15 Eagle because they have the same length.

Umm...whats wrong I only see three ships as well.

I'll give you a hint:

"Two of the K'Vort-class ships attacked the alternate Enterprise-D and destroyed her, while Picard and crew bought time for the Enterprise-C to return to its own timeline."

Since whoever wrote the article used the word "two" and not the number it's not a typo.