Ork Bommas or Bommers are an entire family of aircraft dedicated in blowing those puny gitz to smithereens. Bommas come in all shapes and sizes but they all excel at their job. They are not to be confused with the Fighta-Bommer who is more of a transitional vehicle than a dedicated Bommer. The list of Bommas include the Blitza-Bommer, Heavy Bommer, Blasta Bommer and Burna-Bommer.
The Blitza-Bommer (AKA Accidental Kamikazes) is an Ork dive bomber suitable for the bravest and most mentally unhinged/unstable of Flyboys. These aircrafts 'aim' their bombs by diving at the target, releasing their Boom Bomb at the very last moment possible which is something that tends to panic the onboard Grot Gunner. They often perform 'Blitz' runs where an entire squadron of these guys start peppering a targeted enemy with a barrage of bombs, hence their name.
Like every Ork mentality, you go much faster when plummeting downwards and if you paint it red you go even faster. Some Orks completely forget to pull out of their dive and end up smashing into the ground. Once they've blown everything up (and hopefully not themselves) then there's a pair of supa shootas ready to mop up any stray or squishy targets.
Blitza-Bommers are typically armed with a pair of Supa Shootas and a Grot-manned Big Shoota. Their payload consists of a pair of Boom Bombs, a heavy type of high-explosive bomb.
In the 8th Edition Index. Blitza-Bommers are Bombers that's a little more focused on attacking vehicles. Its guns are still anti-infantry (with the Grot Gunner giving it a +1 to hit with the Big Shoota), but its Boom Bombs count VEHICLES and MONSTERS as three models when working out how many dice they get to roll for mortal wounds - and they inflict mortal wounds to all targets on 4s, while Burna-Bommers' Burna Bombs require 5s for non-INFANTRY.
Bomb squadrons of smaller vehicles for maximum pain.
As their name implies, Heavy Bommers are one of the largest available Bommers in use of the Orks built for sustained heavy bombardment. Due to their size, Heavy Bommers can carry a much bigger payload then their smaller cousins. They are also far more noisier, which complements the Orkish aerial bombardment doctrine of BIG BADDA BOOM! The main problem with Heavy Bommers is there aren't many Orks willing to pilot them, either because the controls are unusually small or the cockpit is cramped. Combine these factors with the universal Ork instinct to fight face-to-face, most of the crews inevitably consist of Gretchin.
Sometimes of course, the bombs malfunction and accidentally blow up inside the Bommer creating a spectacular fireball of Fail.
In 7th Edition of Imperial Armour 8, Heavy Bommers are like the Fighta-Bommers only bigger and slower with more dakka and ordinance. Enough defensive weaponry is on this thing to see off waves of interceptor aircraft, while it carries enough ordinance weapons to pretty much wipe out an entire formation on turn one. Just one of these can spit out enough supa-rokkits to wipe an Leman Russ company off the gameboard or drop enough grot-bombs to turn six full sized Gaunt Broods with an accompanying Hive Tyrant with Tyrant Guard and Warrior Prime (about to tear into your front lines) into a few scattered bugs and a lonely Hive Tyrant who will be blown apart by your Lootas next turn. It also comes with eight (8!) Big Shootas mounted along the flanks, which can shoot at differing targets.
A sub-category of Heavy Bommers, called Blasta Bommers, are completely retrofitted with nothing but guns and sent out to, predictably, *blast* the enemy to bits with hot lead. The Blasta Bommers are meant for executing low-flying ground attacks, and therefore they are armed with a plethora of Shootas, Zzap guns, and Rokkits. Of course this means that they have to sacrifice space normally designated for their bomb payloads in order to store ammunition and add mounting points for their plethora of gunz. In real life, dedicated light and medium bomber aircraft were actually converted into gun-laden assault planes. These are known as Attack aircraft, though the Blasta Bommer combines this concept with that of the Flying Fortress by mounting a number of independent machine guns along its flanks.
Apparently the (in)famous Ork philosopher and mekboy supreme Orkimedes was inspired by Imperial Marauders and came up with idea for the Blasta Bommer during the Third War for Armageddon. Most Imperial authorities would consider this flattering, but the AdMech would have a collective seizure (brimming with Rage and screaming about tech-heresy) if you dare tell them that a filthy xeno has vandalized the concept of one of their vehicles.
In 7th Edition of Imperial Armour 8, the Blasta Bommer is very much like the Marauder variant for Imperials, instead of bombs and ordinance this thing carries lots of heavy guns for ground attack. Think of this as an Orky A-10 Warthog (the Orkiest of all airplanes). It can crank out a hilarious amount of Shoota, Zzap Gun, and Rokkit hits to mow down large numbers of enemies, while having the range to buzz around, loitering out of reach of the enemy's guns. The lack of Blast weapons means this is more suited for destroying a few hard targets over obliterating large formations, playing counterpart to the traditional Bomma. However, it is the death of Titans, MEQs, and any vehicle anywhere. Just think of it in terms of it's gun: 120" Range, Str 9, Ap 3, Heavy 3D6, plus D3 Supa Rokkits.
The Burna-Bommer is a type of Ork attack aircraft. For some Flyboyz, guns might not be as fun as flamethrowers. Orks love fire and it was therefore inevitable that someday a Mek would think of attaching canisters of volatile promethium to the underside of an Ork Bommer, thus the Burna-Bommer was born. And like their Blitza-Bommer cousins, this aircraft performs its attack runs at as low an altitude as possible. Such a technique is, predictably filled with potential Fail.
Burna-Bommers usually feature a twin-linked Supa Shoota and a Grot-manned defence turret, armed with a twin-linked Big Shoota. Their payload includes two Burna Bombs and up to six incendiary Skorcha Missiles.
In the 8th Edition Index. Burna-Bommers have tons of anti-infantry firepower and, with the bombs, mortal wounds too. You get two Burna Bombs, and can drop one per turn on a unit you fly over. You roll a D6 for every model in the unit they drop on (capped at 10), inflicting a mortal wound for every roll of 5+, or 4+ vs INFANTRY. The Twin Big Shoota gets +1 to hit thanks to its Grot Gunner.
Try to make sure the Bommer is over the enemy when it gets shot down, as the 3 mortal wounds from its 4+ Explosive Demise will be very unpleasant for anyone within 6". These planes are probably more focused on attacking heavy infantry such as TEQs against GEQs you're better off bringing a dakkajet.