bkthunder

P.S. the g-meter in an airplane is measuring g-load on the vertical axis. If you're falling down vertically at a constant speed, the gmeter reads 1, because that's the force of gravity on the planet we live on. If it read 0, the plane would be floating, not falling. Stalling at 0g is imposisble by definition, because at 0g the airplane is weightless, and the wings don't carry any load (on top of that, you'd be on a parabolic trajectory with your AoA close to 0, so you couldn't stall anyway). Depending on where the pilot / gmeter is sitting relative to the CG of the aircraft, you could experience some positive/negative or centrifugal g (for example in a flat spin or if the nose is oscillating up and down).

LOL! if you consider a simple stall to be out of envelope.... well. Have a good one fellas, I've contributed enough to this useless thread :thumbup:

Well, it's kinda hard to find data on an aircraft maintaining 2g during a stall... that's because maintaining 2g with a stalled wing is, as far as my common knowledge of aerodynamics goes, impossible. I really don't think anyone should be explaining this to a developer who is suppsoed to prdouce a flight model, anyway: The wing produces lift > the lift makes tha aircraft fly > the wing loading during normal flight is such that the weight of the aircraft is "supported" by the wing > during a stall the wing has (nearly) no lift, therefore the wing loading is lower than the weight of the plane > the airplane falls. Ergo, if the lift is not enough to maintain flight (and therefore to produce a force that is at least equal and opposite of 1g in the vertical axis), how can it be enough to produce 2g? So, can you explain how is this possible?

There is. Instead of generating confusion by telling people they are wrong (when, in fact, you are wrong) why don't you grab the MiG-21 and verify for yourself? He even gave you the link to the bug report which has been ACKNOWLEDGED by the developer.

Had some time to try it out, unfortunately I'm still getting the random crash. Seems less than before though

You're missing the text I quoted in the previous post, which is before what you put here as point 2. Anyway, the picture tells a slightly different procedure, and I am also not hung up on the 40-50 deg nozzle parameter. But I think this is all quite open to interpretation hence why already a few posts ago I said this is one case where input from a real harrier pilot would be invaluable.

FAM 2-62 point 2. "On downwind, ensure the nozzles are no greater than 25° then select AUTO flaps and complete the landing checklist. On downwind select 40-50° nozzles. Set desired power, and as the AOA increases, anticipate the nozzle movement required to stabilize at 8-10 AOA." As they put it, I understand that 1. You set the nozzles at 40-50 2. You set desired power (e.g. 85%) 3. with nozzles at 40-50, my AoA starts to increase, so then I play with nozzles to achieve 10 degrees in level flight. Increasing AoA = decreasing airspeed = with nozzles at 50 I should be slowing down. As it stands in DCS, with nozzles at 50 my speed keeps going up (and AoA goes down). So I either have to set nozzles at something like 70-80, or reduce power (however, according to the procedure above, I shouldn't touch the throttle anymore).

Didn't see those numbers either in the manual I have. However it does say that when first selecting 40-45 deg. nozzles, the AoA should rise, while in the sim it does the opposite because at 45 degrees you are not slowing down at all.. you need much higher angles to start to slow down...

Just reading the NATOPS, the Harrier has a huge number of quirks to be aware of. Especially when using vectored thrust close to the ground. I guess these could be scripted to a certain extent? I'd personally rather have a scripted behavior than nothing at all.

Whilst there *might* be a slim chance, I am pretty sure you haven't applied basic reading & comprehension skills :music_whistling: Thankfully some other members have understood the OP is not an attack on Razbam or the current FM (if anything, it's the opposite). I think with such a unique aircraft, we all have to come to the realization that our beloved sim and our beloved PC don't have the horsepower to properly compute a VTOL flight model to the same level of accuracy we see in other modules / flight regimes. But 1. I don't know what the sim is capable of calculating in terms of fluid dynamics 2. I don't know how realistic of a result can be obtained by "bypassing" the problem somehow. Hence the thread. For discussion, as you do in a, you know, forum.

The last few exchanges I had on this subforum regarding VNSL landings made me think that, apart from straight and level "conventional " flight, it will be hard to see realistic beahvior during slow speed vectored thrust operations. Why? Well, for starters, just skimming through the AV-8B manual you'll see how the interactions between the engine exhaust, the ground and the airframe are responsible for a huge portion of how the aircraft behaves. Most of these effects are given by air cushioning, the jet blast bouncing off the runway and hitting the wings or stabs (e.g. IRL this causes a pitch down moment when approaching close to the ground). So the real question is: does DCS model fluid dynamics required to simulate these effects? I don't think so. How can we then expect Razbam (or anyone) to model a realistic Harrier FM with such limitations? The only way is that they find some ways to "trick" the simulation engine, but it doesn't seem very promising to me... So we'll probably have a realistic FM in forward flight, but during VTOL, I have big doubts we can see it with current sim technology (and computing power on a home PC).

Hard to say it's an FM issue in my opinion. From what I've seen it really depends on your weight. Try it with a full load of fuel and 85% RPM won't be nearly enough to keep you afloat with a steep N angle.

+1. I was flying at constant altitude (45.000 ft) and fuel flow was stuck at 139 from M0.8 up to M2.2+ Shouldn't work like this.

I don't think so, if you're level it works fine. P.S. shame it was reported so long a go, and wasn't even acknowledged, let alone fixed.

Yep, that seems wrong too...

Please see the image attached. The top 2 shots are from the Harrier, the bottom one is the F-18. The Harrier VVI is wrong, why? As you know there is a "True Velocity Vector Indicator (TVVI) and a "Ghost Velocity Vector Indicator" (GVVI). When the hud is caged, the GVVI appears if the true flight path deviation is more than 2 degrees left / right. In the Harrier, in NAV mode the HUD is always caged, so the TVVI is not showing the true flight path when, for example, you have a strong side wind, he GVVI does that. That's all good while flying straight, however, if you bank the aircraft in a level turn, both the TVVI and the GVVI should sit at the same level on the horizon, but this is not the case in the Razbam Harrier. The result is that in a level turn, only the GVVI sits on the horizon, while the TVVI is higher up a few degrees, which is totally wrong, as they should both indicate exactly the same pitch attitude. The correct version is how it works in the Hornet, where VVI and ghost VVI are moving relative to each other, so in a level turn they both sit on the horizon, corretly indicating wether you are climbing or descending. You can give it a try for yourself: Set a mission with a strong side wind, make a level turn keeping the TVVI on the horizon. With the Harrier you will either climb or descend unless unless you use the GVVI as reference, while in the hornet you will stay at the same altitude. This is a pretty big oversight!

I confirm this. While you get the 2% RPM increase under certain circumstances, I never reached the temp at which the CMBT light turns on. I remember seeign it work a few patches back (I mean harrier patches, so probably last year :music_whistling: )

The TPOD is nowhere near where it should be, it can't even be slaved!

I'm gonna try a few more flights before calling it quits. It definitely is a challenging maneuver if you think about it, and I suspect there's more to it than what you can read in a manual (a case where I REALLY wish a RL Harrier pilot coudl chime in): in my admittedly superficial analysis, I see the following: - 10 degrees AoA in level flight can be maintained at a variety of RPM and Nozzle settings. This will also depend on the weight of the aircraft. - The manual says to drop the nose 5 degrees at the 180, and start a turn. Well, if I drop the nose without reducing power, my speed will increase and my AoA will decrease, so what should I do? I have two options: option A: I nozzle out to increase AoA, but this will make me loose altitude and eventually increase my speed even more as I direct more thrust towards the back. I should probably pull the stick to reduce sink rate and increase AoA, but in the sim I can't do this and keep 5 degrees nose down... option B: I increase nozzle angle to slow down, momentarily the AoA will be further reduced, but my speed decreases and I start to drop, beacuse I don't have enough RPM to sustain the aircaft at such speed/weight/nozzle angle... There is probably a tiny sweet spot in there somewhere...kinda hard to tell where though given that the manuals don't give any references to speeds and power settings connected to aircraft gross weight :huh: EDIT: I got it wrong, the manual says to increase nozzle angle to increase AoA and vice versa. So, the opposite of what I was doing. I'm doing more testing and getting the hang of it. It's fundamental to set the FPM where you want it with the stick, and at the same time change nozzle angle to maintain AoA. When you push the stick forward, increase nozzle angle, when you pull the stick, nozzle out. Practice I guess! Also, don't get fixated on the 40 degrees nozzle angle stated in the manual. It says to set it to 40 and then adjust as required.

Can you please ask your real MiG-21 pilots to test the following and report back (if they haven't done so already)? - High AoA behavior - Comment on the aircraft having negative AoA and flying slughtly nose down in level flight above ~490 Kts - Confirm the aircraft INSTANTLY snaps to 2g whenever entering an exiting a stall, irregardless of the starting conditions. - Confirm it is possible to steer the aircaft on the ground by using the rudder only (no brakes) at speeds as slow as 4 Kts (no wind).

Sorry to be always the negative one here but... are you saying the real MiG-21 stalls in a scripted way, locked at 2g as we see now? Wow. The positive note is the CE2 looks great!

Starting to be slightly worried about features being removed and nothing being fixed / added...

Ok, I gave this more than one try and I have exactly your same problem. Don't know if it's a FM problem, or just I don't get how to do it. I tried many combinations and nothing works, X throttle setting with Y nozzle angle gives level flight, but as soon as I start to turn off the 180, that throttle setting is not enough to keep me airborne, speed goes down, AoA goes up, increasing nozzles angle shoudl reduce AoA but I don't have enough throttle, so I slow down. Only option is to nozzle out and add power.

Balkans including Italy (as in BMS)

Why is the stick straight and not offset to the left as it should be?