SF2E Cant get Harriers to VTO

[Hokum 0]

So if it doesn't, adjust the data.ini using those numbers and it should.

 

Being in IT, editing an ini holds no fear, but out of interest what units is the ini in? Metric or Imperial? If its simple i'll extract it and give it ago.

[+Dave 2,319]

Metric or Imperial?

 

Hieroglyphics.

[Hokum 0]

Hieroglyphics.

 

:P

Thanks Dave...

[+kreelin 2]

...

Thrust of Rolls-Royce Pegasus 101 turbofan 19,000 lbf + 1,000 lbf from reaction stabilisers. = 1.21 to internal weight. So the GR.1 "should" be able to VTO with max internal fuel...

 

Are you sure about the "+ 1,000 lbf from reaction stabilisers." ?

 

AFAIK The reaction stabiliser power is from the main engine so it's already in the 19,000 lbf... So the thrust / weightratio is just around 1.1. Not safe enough to practice a VTO.

And remember that in RL, you have 100% of power for a few minutes only(specialy when hovering) before overheating the engine.

 

An USMC Harrier vet (Deacon) told me that in RL a 1st generation of Harrier can VTO safely with max 50% of fuel and 2 AIM9

Edited June 23, 2009 by kreelin

[+bobrock 15]

Hieroglyphics.

 

lol not so far from truth:

Fuel is in Kg and thrust in Newtons

[+Crusader 2,077]

The maximal power with water injection is only available for a few seconds ( 15-20 or so), without damaging the engine. There is a "limiter" which the pilot can override in an emergency, but this can result in engine damage.

BTW, my example above doesnt include weight of the pylons and fueltanks itself, this also applies to Hokums GR.1 math... tanks itself weight ( as a rule of thumb) 8 - 10 % of the fuel they can hold.

 

The air for the reaction control system is bleed air taken from the engine compressor, and thus already a part of the total thrust available.

 

And again, on a hot summer day or in the tropics, engine perfomance (available thrust) is reduced very noticable.

 

Plus, the engine "on paper" available thrust is often not reached by engines, for one reason or another ....

[Hokum 0]

The GR.7 seems to have a max take off weight VTO of "18,950 lb"

http://www.military-aircraft.org.uk/jet-fi...harrier-gr7.htm

 

Are quoted thrust figures wet or dry?

[Hokum 0]

lol not so far from truth:

Fuel is in Kg and thrust in Newtons

 

I have the figures in Knewtons...

[+kreelin 2]

....

 

Are quoted thrust figures wet or dry?

 

Its dry... Now PC on Harriers

[+331Killerbee 840]

[+331Killerbee 840]

VTO on Ship.....

 

 

The Aircraft I loaded returning VL to Ship......

 

 

VTO on a Land Base....

 

 

If a Harrier has only 10 to 15 Seconds of VTO Time, It couldn't fly backwards, huh?

 

 

Launching VTO on Carrier....(Courtesy of the U.S.Navy)

 

Edited June 23, 2009 by 331Killerbee

[+331Killerbee 840]

I doubt You'll find this in any Wiki........

 

 

P.S. Another reason they put Stopwatches in the Cockpits......

Edited June 23, 2009 by 331Killerbee

[Gr.Viper 131]

Still, weight limit is pretty.. limiting.

 

Anyway, if you hold the joystick right VL on SF2E Harrier is not that hairy. You can even get to 0 airspeed without stalling or spinning

[+kreelin 2]

KB,

 

All you are showing is for BII+ (or GR7)... Hokun's question is about GR1.

There is a "gap" between those birds.

 

You certainly remember of Deacon211. He helped me very closely for the AV-8C FM. He told me that for the first generation of Harrier, the VTO was possible only with 50% of fuel max and 2 AIM9.

Edited June 23, 2009 by kreelin

[+331Killerbee 840]

50% Max Fuel and 2 AIM-9's was for everyday Operation to keep Engine Service Life up. GR.1's (AV-8A/C) didn't fly with Stores on all five Pylons and Gun Pods on a everyday basis. True. But I contend the capability was allways an option to have a fully loaded AV-8A (GR.1) All 5 Pylons Loaded with Gun Pods, or AV-8B (GR.7) Fully Loaded with Gun Pods to Vertically Takeoff if the Mission Requirment deems nessary.

 

The Statement that it can't or won't is False. That's My contention. I saw it done on a Daily Basis in 1985 durning AV-8B OPVAL conducted by VX-5 at Pax River, MD. I was there. Saw it with My own Eyes.

 

If this was not a Combat Capability the Marine Corps could have, I doubt they would have bought the Aircraft in the first place in 1971. As I served with the AV-8B, I spent just as much with TA-8A/C Aircraft also. Sure, This wasn't done on a regular basis. But while at VMA-231, We set the World Record in Turn-Around Time for a Combat Aircraft at Lyman Road at Camp Lejune, NC in 1979. The Record Set was 5.5 Minutes for a AV-8A Loaded with Full Ammo Packs to the Aden Guns, 3 Mk.82 Snakeyes and 2 LAU-7 with Nitrogen Bottles and ADU-299's with the AIM-9L's loaded and the Aircraft fully Fueled. After the Time was taken, The Aircraft preformed a perfect VTO from a two Lane Highway......

 

 

Yes, It can.....Is all I'm saying.

[+331Killerbee 840]

Here's what I've found testing the Harriers in SF2E in Normal Mode. The GR.1 has no problems in the Area of RCS. The RCS works fine. But the Aircraft won't VTO. Even Slick. The AV-8B will (Slick), but with a Nose Up trajectory or increase of AOA to the Nose.

 

The Reason I can tell in the AV-8B is that it has 4 Engines assigned to the Nozzles that have a SLDryThrust of 24000. The GR.1 has front Nozzles set at 18183.3 and the Rears set a 24074.3. If I set the GR.1's SLDryThrust to the B's Values, I get the same Nose Pitch up.

 

Again, This is in "Normal" Setting.

[+331Killerbee 840]

I think the Problem stems from the Fact that the FM is using 4 Seperate Engines to control overall Thrust.

 

I recommend Keeping the 4 Engines for the Nozzle Animation. Make them "Dead" as far as Thrust goes. Add a Engine that Simulates VTOL and another for Foward Flight. RCS will take care of the Balancing in VTOL. In "RL", A Harrier only has one Engine.....Not 4.

 

Unless anybody else has a better Idea......

[zmatt 2]

Wow your a wealth of information. Anything that can be done to make the Harriers better is a good idea in my book. I was a little disappointed to find that you couldn't VTOL unless you completely unloaded the plane in game. I wondered what that point of a jump jet was.

[+Crusader 2,077]

The game doesnt take into account that air and exhaust is trapped below the fuselage, between the gunpods or strakes in their place. Later Harrier models have the big strakes ( going by the name of Lift Improving Devices - LID - ) and a small air dam on the front.

All this produces ~ 1000 lb or more ( depending on model/ configuration) lb of extra thrust .

[Gr.Viper 131]

I wondered what that point of a jump jet was.

Well...

The primary mission of the RAF Harrier is to provide combat support for British I Corps Germany. In tactical exercises, the Harrier squadrons break into three flights each and disperse to the countryside, where they go into hiding among the trees and under camouflage nets, with rubberized fuel storage tanks some distance away. Take-offs are performed on a 180-meter stretch of aluminum planking, though in actual combat operations any reasonable roadway would do just as well.

 

From these hidden forward sites, pilots remain on station in the cockpit to await a call for fire support from a forward air controller through a Forward Wing Operations Centre. Typically the Harriers would take 20 minutes to perform the strike and then, munitions expended, return to their base site to refuel and rearm. A Harrier pilot could easily fly six sorties in a single day.

[+331Killerbee 840]

The game doesnt take into account that air and exhaust is trapped below the fuselage, between the gunpods or strakes in their place. Later Harrier models have the big strakes ( going by the name of Lift Improving Devices - LID - ) and a small air dam on the front.

All this produces ~ 1000 lb or more ( depending on model/ configuration) lb of extra thrust .

 

This is exactly right. The Cushion of Air is very Important. (BTW, The small Air Dam behind the Nose Gear is the "LID".)

 

A 1000 lbs is alot to factor in.....

 

Max TO Weight (Vertical) AV-8B 20,755 lbs

Thrust F402-RR-408 23,500 Lbf.

Max TO Weight (Vertical) AV-8A 17,260 lbs

Thrust F402-RR-402 21,500 Lbf

Edited June 23, 2009 by 331Killerbee