The hawk is my second favorite vehicle ever, second only to the vulture and I love the grizzly!
SO WHERE DID THEY ALL GO???
not ONE in ANY mainline game.
they need to bring in the big guns (them) to make this franchise great again, and fun as hell!!
Well, the Hawk and Grizzly were allegedly pet projects by the doctor and forge.
Expect them in Halo 6 onwards.
I wouldn’t get your hopes up on the AV-22 Sparrowhawk and the AC-220 Gunship. The Grizzly would just be a waste of time, as it’s simply a Scorpion with 2 barrels. Also, as mentioned in the ‘lore’ on the Spirit of Fire. Since it was ‘lost’ (but somehow returns in Halowars 2 to fight the Banished), the UNSC never learned about the Flood, or could ever be able to produce the Grizzly or Sparrowhawk. The AC-220 Gunship would be too bulky for Warzone and could probably be bashed into the ground by a simple SPlaser blast, like most aerial vehicles. We do not need the AV-22 with the introduction of the AV-49 Wasp, and a chin mounted non-linear beam would be quite awesome, but we already have the Phaeton Helios for a weapon like that. The Wasp has twin-linked machine guns and so did the Sparrowhawk, so we’re good on that too. The Sparrowhawk wouldn’t have shields, and the Grizzly doesn’t have the whole nonlinear cannon that the Hannibal has, or the mini-laser turret.
Link to wiki for Hawk
According to the halo nation wiki, link above, the Hawk had issues with its ducted fan propulsion system, which limited its deployment after 2550.
The reason why Grizzlies are seen in Halo Wars 2 is because the spirit of fire had a robust outfit of them (in other words had a lot of them).
Link for Grizzly
If you have any more questions, the whole wiki pages should answer the rest for you, hope this helps 
Well some people know their stuff. Doesent make me feel much better though.
And one one of you are looking at this all wrong. You are looking at them through warzone only, not thinking about big team or anything. Also you are looking at it solely from 5’s perspective.
This is is not the connotation I wish to evoke when introducing these grand vehicles. I believe the wasp is horribly designed and simply doesent belong in halo. Although that is my aesthetic oppinion I’m sure others share it, or at least a variant. I also believe the hawk and grizzly were very well designed and I think it would be a tragedy having the hawk and grizzly next to something like the wasp. Ewww,
also so the phaeton Helios is OP and needs to be nerfed. I also believe the hawk would need some nerfing as well to make it work but it is just such a beautiful design. Unlike that of the lazily put together wasp. See, it makes logical sense going from the hornet to hawk. Where does the wasp come from? It’s original, and that’s the problem. Having nothing else to draw from makes it take from 343s current art direction which is pretty lazy in general and not as good as past games.
I challenge you to think of it in terms of halo 3 big team. Say halo is that great now and said vehicles could be introduced in the next iteration. Also forget the vulture in MP, I never said that would be fair XD
Also I know the lore said they had engineering problems but those could easily be remedied with solutions. Happens all the time in the real world. Or they could be fixed with forunner tech upgrades or something. I mean, isn’t that basically the infinity?