i do know this though, according to Star Trek canon, Plasma weapons are quite weak vs Federation (and most other types) of shielding and armor.
conversely, Star Trek particle weapons can be modulated to bypass shields or overload them (you know, targetting certain systems like engines, weapons, shields etc) not to mention the hellishly powerful Mk IX photon torpedos (ST:Voyager, im not sure if DS9 and Enterprise carry the same, but it would be very close)
also, Star Trek has transporters... beam a torpedo or spacial (yes, spacial) charges over to the reactor of a Covenant Ship... Game Over
Lastly, Star Trek ships can fire while at warp, and Federation ships in particular are highly versatile. Most if not all systems have multiple redundancies, and damage can be repaired by bypassing or re-routing through other systems. Star Trek ships are more manouverable and possibly faster than Covenant.
And in the Federation alone there are many more races than make up the Covenant, each with its own military (usually) and varied weapons, so the covenant would have to beat superior numbers as well as superior fire power. and thats if the Federation didnt somehow get Klingons, Romulans, Bajorans, the Dominion or even the Borg involved. hell, they could bait the Borg with Covenant ships, watch the blood bath, and pick up the pieces later
Federation vs UNSC? Federation no contest. The MAC guns (i hate that word! Magnetic Accelerator Cannon gun... grr) might give federation ships pause... i think they hold up against meteors etc pretty well...
In terms of ground combat, well, we dont know much about Star Trek ground combat. we know many races keep standing armies (DS9 Dominion War), but its possible elite shields and sheer brute strength, not to mention armor etc, could give Star Trek a run for its money...
unfortunately, we dont know about Star Trek ground combat tactics, strategies and abilities, so its impossible to comment
Will on the Plasma weapons it would seem to me that Covenant weapons would be a lot more powerful then ST plasma weapons. And I'll list Covenant weapons and such again here: Plasma Torpedos are powerful charges of plasma that is shaped and guided using magnetic fields over many millions of kilometers at half the speed of light and can easily hit ships and stations. Pulse Laser Point Defense Turrets can shoot down anywhere from many dozens of missiles for small ships to maybe hundreds for larger ships such as the massive Assault Carrier and Supercruisers. Energy Projectors are the most powerful weapon know to be used by Covenant ships, its known range is around 100,000 kilometers and is a light speed weapon that can gut multiple unshield ships in one hit. E-Ps can be fired in laser thin lances of massive power to gut and destroy any unshielded ship and take most shields down in one hit. They are also fired in massive beams that can cover large areas when the Covenant begin glassing human worlds. The Covenant ship with the most Energy Projectors is the Covenant Battleship at 2000 meters long and wields 12 of these powerful weapons. Please go to Halopedia and read the books The Fall of Reach and First Strike for more info.
And even if Transporters can get through Covenant shields it may not go through the hull and the mag fields used for the Plasma Torpedos may mess it up. But that is a major threat to any ship that have it's shields down and any gaps in the hull near the reactor.
And to another post from a few pages back that said something about Fed ships firing at the center of mass that may disable it, that may not work, and this should give us some idea of the damage a small Covi ship can take. Quote." MAC at one hundred percent," the weapins officer shouted."Ready to fire!" Fire!" Captain Wallace ordered. The lights on the bridge dimmed and the Commonwealth shuddered. The MAC bolt launched through space-a red hot metal slug moving at thirty thousand meters per second. The Covenant ship's engines flared to life and the ship veered away- Too late. The heavy round closed and slammed into the target's prow. The Covenant ship reeled backward through space. Its energy shields shimmered and glowed lightning-bright... then flickered, dimmed, and went out. The bridge crew let out a victory cheer. Except Dr. Halsey. John watched the view screen as she adjusted the camera controls and zoomed in on the Covenant ship. The vessel's erratic spinning slowed and it came to a stop. The ship's nose was crumpled and atmosphere vented into vacuum. Tiny fires flickered inside. The ship slowly came about and started back toward them-gaining speed." It should have been destroyed," she whispered. Unquote. And here's the next round to hit it. Quote." Send them to Hades, Lieutenant. Fire." The lights dimmed again. The Commonwealth shuddered and a bolt of thunder and fire tore through the blackness. The Covenant ship stood its ground. The bloodred light that had pooled on its lateral line burst forth-streaked toward the Commonwealth, passing the MAC round a mere kilometer away. The red light glowed and pulsed almost as if it were liquid; its edges roiled and fluttered. It elongated into a teardrop or ruby red five meters long." Evasive maneuvers," Captain Wallace cried." Emergency thrusters to port!" The Commonwealth slowly moved out of the trajectory path of the Covenant energy weapon. The MAC round struck the Covenant vessel amidships. Its shields shimmered and bubbled... then disappeared. The MAC round punched through the craft and sent it spinning out of control. Unquote. Pages 108-109 The Fall of Reach. And before anyone says anything I know it said a godamn 30,000 meters per second! It should have said 30,000 kilometers because that would get across the 80 million kilometers that could be done by it in about 44 minutes if I did the math right. And so it seems that a Covenant ship can take a good amount of damge even a small one like that.
And I know they can fire from Warp, but the Covenant can shall sneak up on them when their in normal space going through the Slipstream. And I agree, ST ships maybe faster then some Covenant ships, but beyond them being at least tiwce the speed of an UNSC frigate for the Covenant frigate that the Commonwealth fought we don't now much.
And the other races in the Federation may be a bad thing if the Covenant get of to a good start and start preaching their crazy "lighting giant rings floating in space to become gods" stuff to those that do not look to human. And unless they have good defenses in space ground forces are worthless: 3 dozen Covenant ships can glass the surface of a world and boil away all the oceans and other sources of water in only an hour, and those are just Destroyers and Cruisers. And I don't know about them being out classed in weapons power, ship weapons (may depend on class) are at least on the same level. And they may get the Klingons help but I doubt if the RSE will help until the Covenant attack them, the others besides the Borg I don't know much about. But I don't think the Borg would be a bog threat since unless there's already a Cube(s) in Fed space it may take time for them to arrive and try and take the Covis out. It may be fun when they start playing that transmission; what do you guys think the Covenant would say back before firing? I can't think of anything right now, but post it if you come up with something funny. And now that I am thinking about it, did that fleet in The Die eas Cast fire Phasers or Torpedos in their attack on the Founders home world? And also, Josef086 and psychoak have you seen that trailer for Halo: Reach yet? It may give us a better idea of Covi weapon power based off the size of those explsions. I'll see if I can find it though and post a link here if I do, but look for it to.
Also, did you read a fanfic were it was called "the Big Mac n Cheese"? I would guess that would be one reason to hate the name. I would think really that the Federation would help the UNSC against the Covenant if they can push the Covie back first.
I have to go with the Covenant on any ground operations since they have better armor then and infantry then anything the Feds in other races have and can just far around thousands of Grunts on the ground as cannon fodder. And one way the Covenant could win easily would be to just park their ships right above cities were no one would dare to attack them without risking the lifes of those below. Just burn any shipyards like the Mars ones and others using planet side cover if possible. I wonder what the mass's of Redshirts would think if they had to fight a Scarab? There goes most of the Federation forces when they run for it. It seems that the Redshirts end up dying in droves all the time. Will tell me if I forgot something or made a mistake.
This has been a UNSC transmission.