The GR7/9s sometimes carried the gun pods if there wasn't enough strakes to fit in place, as they essentially did the same job as the strakes in the hover, forming the box section with LIDS fence, strakes/gun pods/tgp and airbrake.
This is more or less how the RAF came to upgrading to the Mk107 engine for the Harrier, which was much more suited to the high altitude and high temperatures.
You can try reading about what happens when the Royal Navy end up in the desert.
https://www.amazon.co.uk/Joint-Force-Harrier-Ade-Orchard/dp/0141035714/ref=cm_cr_arp_d_product_top?ie=UTF8
They can only really hover dry with the Mk107 engine, gave them that extra bit of thrust and essentially took away the need for the water tank. It stayed for ballast obviously.
Nice one Bill :)
With the Mk105 and 107 engines the water is mainly there as ballast unless operating in high temperatures and/or altitudes. Otherwise, the water is used for water injection when the aircraft is set to 'Short Lift Wet' or 'Lift Wet' mode for hover and short take offs/landing. The engine is temperature limited so to get some more power the water is sprayed onto the turbine blades and around the combustion chamber to assist cooling and allow more fuel to be pumped in. The pump is air driven from engine bleed air, gives you about 90 seconds hover time.
Haha, I have just had a look at some videos of the FSX version, it looks like they have got it pretty much spot on! A few points, it might just have been the video I watched or FSX limitations or AV8B specific. You should be able to disengage NWS, anti-skid and NWS won't work at the same time. You should be able to start the engine without firing the APU gen up first. Flaps need to be reset before they even think about working. It doesn't look like water flow and IGVs are modeled? Most of that is just being picky!
I'm tempted to dig FSX out and give it a go, I miss the old carbon fibre death provider!
Harriers are close to the EGT limit when they are in the hover, at altitude and in high OAT it gets very close, you wont ever see them hovering with much loadout if any. Harriers also use water injection when hovering and for STOL, it gets sprayed around the combustion chambers and onto the turbine blades, which as Rico mentions lowers EGT and allows more fuel flow.
OBOGS has nothing to do with LOX does it? At least in the systems I have worked with they just use an MSOCS to provide the pilot with what is basically nitrogen free air from an engine under a bit of pressure...oxygen? :)
PS Dont drink de-min water its not good for you :)