Flight model realistic / ok?

[Coxy_99]

Having flown it ive had no issue with its flight model, I trust in Razbam to get close as possible, Another point missed is THIS IS NOT REAL LIFE BUT A SIM, In other words it wont be perfect for sure, Theres only one way to deal with this FM issue DONT FLY IT ;)

[some1]

Dude, you need all you where talking about, were Laser GUIDED Bombs/Paveway (laser and GPS) and JDAM... SMART bombs!

These you drop from safe altitude, with no hard maneuvering. DUMB bombs are usually dropped in pairs.

As for the photos, if you have read the books a couple are taken from you should know, the Hunter configurations, with the TGP, use the LGB as counterbalance and rarely dropped them because of the induced roll and imbalance.

 

Dude.

 

Go educate yourself on the subject, for example read Joint Force Harrier by Ade Orchard.

There's a nice description of dropping a single dumb 540lb bomb on Talibans' heads from a steep dive.

 

RAF flew them like that all the time in Afghanistan, in mixed configurations. One aircraft carried heavy LGBs, the other unguided rockets and dumb bombs. The dumb bombs even had different fuzing, one being set for airburst, one for impact, and JTAC chose which one should be used. I already posted a photo of a Harrier with 540lb bombs on the outermost pylons, the same photo is actually in the book.

 

Also, RAF flew their Harriers with TGP's on the underbelly, so there wasn't anything to counterbalance.

 

As for the FM discussion, I don't think I've ever lost control over Razbam's Harrier due to asymmetric payload, although it is quite noticeable. Is it realistic? No idea.

Edited February 8, 2019 by some1

[JaBoG32_Herby]

@mvsgas

You’ve asked the question whether the airframe simulated has 65 or 100% LERX.

 

I’ve used Figures 11-3 and -4 in the -000 Manual and more specifically the buffet onset curve at low IMN to figure this out.

I presume, based on the results, that RAZBAM modeled a 100% LERX variant.

 

But again, this is more of a speculative nature derived from my observations than it would be scientifically proven.

[Harlikwin]

Having flown it ive had no issue with its flight model, I trust in Razbam to get close as possible, Another point missed is THIS IS NOT REAL LIFE BUT A SIM, In other words it wont be perfect for sure, Theres only one way to deal with this FM issue DONT FLY IT ;)

 

Mostly this. I have flown real aircraft (not the harrier obviously). And it flies like a simulated aircraft should I guess. IMO there is too much thats wrong on the sim side, no feedback from the stick, magic auto-centering stick when it comes to be able to say if the Harrier "feels" right. As far as the FM, as long as it can replicate the speeds/handling characteristics per the manual (which it seems it can) I'd say its GTG. The asymmetric weight/drag/etc issues, maybe they are overdone but I've never had issue trimming them out even when using bombs or mavs or whatever. Landing vertically with an asymmetric load is another story, but I bet thats fairly accurate.

 

Personally I'm much more concerned with the state of various systems modeling (ARBS/DMT/CCRP) than the FM at this point.

Edited February 8, 2019 by Harlikwin

[mvsgas]

@mvsgas

You’ve asked the question whether the airframe simulated has 65 or 100% LERX.

 

I’ve used Figures 11-3 and -4 in the -000 Manual and more specifically the buffet onset curve at low IMN to figure this out.

I presume, based on the results, that RAZBAM modeled a 100% LERX variant.

 

But again, this is more of a speculative nature derived from my observations than it would be scientifically proven.

 

Thanks, that is why you get paid the big bucks.

Sorry, I know this is not appropriate, but I think

is a funny adequate response in appreciation Edited February 8, 2019 by mvsgas

[Coxy_99]

Mostly this. I have flown real aircraft (not the harrier obviously). And it flies like a simulated aircraft should I guess. IMO there is too much thats wrong on the sim side, no feedback from the stick, magic auto-centering stick when it comes to be able to say if the Harrier "feels" right. As far as the FM, as long as it can replicate the speeds/handling characteristics per the manual (which it seems it can) I'd say its GTG. The asymmetric weight/drag/etc issues, maybe they are overdone but I've never had issue trimming them out even when using bombs or mavs or whatever. Landing vertically with an asymmetric load is another story, but I bet thats fairly accurate.

 

Personally I'm much more concerned with the state of various systems modeling (ARBS/DMT/CCRP) than the FM at this point.

 

 

Yep.

[shagrat]

Dude.

 

Go educate yourself on the subject, for example read Joint Force Harrier by Ade Orchard.

There's a nice description of dropping a single dumb 540lb bomb on Talibans' heads from a steep dive.

 

RAF flew them like that all the time in Afghanistan, in mixed configurations. One aircraft carried heavy LGBs, the other unguided rockets and dumb bombs. The dumb bombs even had different fuzing, one being set for airburst, one for impact, and JTAC chose which one should be used. I already posted a photo of a Harrier with 540lb bombs on the outermost pylons, the same photo is actually in the book.

 

Also, RAF flew their Harriers with TGP's on the underbelly, so there wasn't anything to counterbalance.

 

As for the FM discussion, I don't think I've ever lost control over Razbam's Harrier due to asymmetric payload, although it is quite noticeable. Is it realistic? No idea.

 

I did read Orchards JF Harrier, actually twice. I was specifically referring to the US Hunter/Killer AV-8B. (A good read on the actual AV-8B btw. in Franzak's "A nightmares prayer").

That steep drop was NOT a dumb(!) bomb!

LGB/Paveway = smart bomb, as in finds its way by guidance systems.

Dumb bombs = Mk-80 series with no guidance kits. Not precise, often unreliable fuses so they are usually dropped in pairs to increase the chance of taking out the target in the first attempt, where chirurgical precision/prevention of collateral damage is not a factor.

[JaBoG32_Herby]

Thanks, that is why you get paid the big bucks.

Sorry, I know this is not appropriate, but I think

is a funny adequate response in appreciation

 

:lol::thumbup:

[some1]

I did read Orchards JF Harrier, actually twice. I was specifically referring to the US Hunter/Killer AV-8B. (A good read on the actual AV-8B btw. in Franzak's "A nightmares prayer").

That steep drop was NOT a dumb(!) bomb!

 

I must have read a different book then:

 

Squid pushed the nose of the Harrier down into a thirty to forty degree dive and began trying to acquire the target.

(...)

The five-forty he was carrying was unguided – dumb – but the energy from my laser was hitting the compound and bouncing back up to his aircraft to provide him with a very accurate firing solution. Then the bomb dropped from beneath his wing, bobbling a little before settling into a steep ballistic dive towards the ground. It speared straight into the target, eliminating – or, to put it more crudely but far more accurately, killing – the enemy gunmen in an ugly cloud of billowing brown dirt

[Shadow_1stVFW]

I think you're looking at the wrong photo. They hung two symmetrically at the outermost pylons.

 

Btw, found an interresting photos, though it may be a test of some sorts. These are 2000 lbs on inner pylons and assymetric 500 lbs on the outer pylon.

 

 

 

These are great photos. Thanks for sharing.

[HWasp]

 

HWasp,

I still not sure if you are saying the FM is missing things or not. Do you have a track showing the behavior you describe?

 

 

 

According to the NATOPS paragraph that you have copied here in your previous posts, yes it seems to miss things:

 

 

" Originally Posted by mvsgas

 

11.3.1.3 Transonic Wing Drop All variants of the AV−8B can experience a sudden uncommanded roll−off, also called wing drop, caused by the abrupt asymmetric stall of the wings. Wing drop occurs suddenly, with little or no warning to the pilot, and may occur at AOAs below the maneuvering tone. The severity of wing drop increases as Mach number increases and as altitude decreases. At Mach numbers greater than 0.8 IMN, wing drop may occur 3° AOA below the maneuvering tone. At greater than 0.8 IMN wing drop may occur 3° AOA below maneuvering tone. The severity of wing drop increases as Mach number increases and as altitude decreases. If wing drop occurs, flying qualities can be improved by reducing AOA.

 

WARNING

Transonic wing drop may occur at angles of attack below the maneuvering tone. Extreme care should be exercised at elevated AOA when maneuvering near ground level above Mach 0.8.

.

"

I have never experienced this behaviour with the harrier. Even at Mach 0.95 you can pull beyond the tone, there will be no wing drop, nothing. There is no change in behaviour due to the high Mach number. I could make a track, but why don't you all just test it? It's perfectly stable, no adverse effects.

 

 

I'm not a harrier expert, just relying on your source...

[Harlikwin]

I must have read a different book then:

 

So someone buddy lasing for his DMT so he would have a nice tgt diamond to drop on... (Which ZOMG we can actually do in the harrier, using CCIP of course).

[Harlikwin]

These are great photos. Thanks for sharing.

 

Wow, cool pics indeed. An outboard 500lb dyssymetry in a "ish" vertical flight config (I can't tell the nozzle angle but its not straight back, maybe like 60?). Then again, we can't tell fwd airspeed either, (under 250?) nor do we know how the fuel in the tanks is balanced. But for low speed asymetrical flight its impressive.

[Shadow_1stVFW]

Wow, cool pics indeed. An outboard 500lb dyssymetry in a "ish" vertical flight config (I can't tell the nozzle angle but its not straight back, maybe like 60?). Then again, we can't tell fwd airspeed either, (under 250?) nor do we know how the fuel in the tanks is balanced. But for low speed asymetrical flight its impressive.

By the numbers, and all things being equal and balanced around 500 pounds on stations 1 and 7 is the upper limit to of asymetry

 

Sent from my SM-G960U using Tapatalk

[Mars Exulte]

I dispute that. While I agree the FM in general is good, and the hover effect is really well made. - There are still issues with uneaven loads! No jet that behaves like DCS Av-8B does would be put into service as it is too dangerous. I drop one measly Mk82 and the whole airframe turns into something that is a really uncomfortable and difficult to fly. The effect is greatly overdone and should be tweaked/fixed.

 

Are you familiar with aviation history AT ALL? TONS of inherently dangerous aircraft have entered service with wide varieties of flaws ranging from 'hmmm that's strange' to 'WE'RE ALL GONNA DIE'.

 

''This behavior is undesirable and/or dangerous'' is not a relevant remark in and of itself, when discussing whether something is ''realistic''. There have been numerous ''flying death traps'' since the Wright brothers first took off, and the US and A has hosted its share of them.

[Harlikwin]

By the numbers, and all things being equal and balanced around 500 pounds on stations 1 and 7 is the upper limit to of asymetry

 

Sent from my SM-G960U using Tapatalk

 

Is that for flight or Vertical takeoff/Landing?

[Harlikwin]

Are you familiar with aviation history AT ALL? TONS of inherently dangerous aircraft have entered service with wide varieties of flaws ranging from 'hmmm that's strange' to 'WE'RE ALL GONNA DIE'.

 

''This behavior is undesirable and/or dangerous'' is not a relevant remark in and of itself, when discussing whether something is ''realistic''. There have been numerous ''flying death traps'' since the Wright brothers first took off, and the US and A has hosted its share of them.

 

The SR-71 would be a great example of an In Service aircraft that was on the "WE'RE ALL GONNA DIE" side of the equation....

 

Hey, we need a Recce platform for DCS don't we?

[FSKRipper]

The SR-71 would be a great example of an In Service aircraft that was on the "WE'RE ALL GONNA DIE" side of the equation....

 

Hey, we need a Recce platform for DCS don't we?

 

The swedish scythe has at least an ELINT pod to do so. Photo recce would need a more advanced multiplayer campaign IMO.

 

No jet that behaves like DCS Av-8B does would be put into service as it is too dangerous.

 

No? I think they didn't followed your recommendation: https://en.wikipedia.org/wiki/List_of_Harrier_Jump_Jet_family_losses

Edited February 8, 2019 by FSKRipper

[Harlikwin]

No? I think they didn't followed your recommendation: https://en.wikipedia.org/wiki/List_of_Harrier_Jump_Jet_family_losses

 

Yeah, thats true, Didn't the Harrier have literally THE WORST safety record of any major fielded combat aircraft?

[TLTeo]

Yeah, thats true, Didn't the Harrier have literally THE WORST safety record of any major fielded combat aircraft?

 

 

From, say, the post-Vietnam generation of aircraft yes.

[mvsgas]

From, say, the post-Vietnam generation of aircraft yes.

 

https://forums.eagle.ru/showpost.php?p=3787727&postcount=13

[mvsgas]

According to the NATOPS paragraph that you have copied here in your previous posts, yes it seems to miss things:

 

 

" Originally Posted by mvsgas

 

11.3.1.3 Transonic Wing Drop All variants of the AV−8B can experience a sudden uncommanded roll−off, also called wing drop, caused by the abrupt asymmetric stall of the wings. Wing drop occurs suddenly, with little or no warning to the pilot, and may occur at AOAs below the maneuvering tone. The severity of wing drop increases as Mach number increases and as altitude decreases. At Mach numbers greater than 0.8 IMN, wing drop may occur 3° AOA below the maneuvering tone. At greater than 0.8 IMN wing drop may occur 3° AOA below maneuvering tone. The severity of wing drop increases as Mach number increases and as altitude decreases. If wing drop occurs, flying qualities can be improved by reducing AOA.

 

WARNING

Transonic wing drop may occur at angles of attack below the maneuvering tone. Extreme care should be exercised at elevated AOA when maneuvering near ground level above Mach 0.8.

.

"

I have never experienced this behaviour with the harrier. Even at Mach 0.95 you can pull beyond the tone, there will be no wing drop, nothing. There is no change in behaviour due to the high Mach number. I could make a track, but why don't you all just test it? It's perfectly stable, no adverse effects.

 

 

I'm not a harrier expert, just relying on your source...

 

Without a track, we can't tell aircraft configuration (weight, load out) at what altitude are you performing this maneuvers. What are the weather conditions, what AOA are you using, etc.

 

[ATTACH]204151[/ATTACH]

 

Open Beta ver 2.5.4.26825, Caucasus map

[ATTACH]204150[/ATTACH]

 

You can see in the track, as I reach .83 mach, buffeting is present and increases at .85. Also, I struggle to climb pass .83 mach at normal engine RPM

Edited February 9, 2019 by mvsgas

[mvsgas]

Lets compare the gyrations to a flight by wire aircraft. Keeping in mind the video does not show the modifications to this F-16

https://forums.eagle.ru/showpost.php?p=3775853&postcount=1151

rMLXkH8Idig

 

 

qg1Ojydzv8U?start=380

Edited February 9, 2019 by mvsgas

[HWasp]

Without a track, we can't tell aircraft configuration (weight, load out) at what altitude are you performing this maneuvers. What are the weather conditions, what AOA are you using, etc.

 

[ATTACH]204151[/ATTACH]

 

Open Beta ver 2.5.4.26825, Caucasus map

[ATTACH]204150[/ATTACH]

 

You can see in the track, as I reach .83 mach, buffeting is present and increases at .85. Also, I struggle to climb pass .83 mach at normal engine RPM

 

 

That is quite violent! It seems to be by the book. :thumbup:

 

 

BUT, that is not the same subject we were talking about.

 

" Originally Posted by mvsgas

----------------------

11.3.1.3 Transonic Wing Drop All variants of the AV−8B can experience a sudden uncommanded roll−off, also called wing drop, caused by the abrupt asymmetric stall of the wings. Wing drop occurs suddenly, with little or no warning to the pilot, and may occur at AOAs below the maneuvering tone. The severity of wing drop increases as Mach number increases and as altitude decreases. At Mach numbers greater than 0.8 IMN, wing drop may occur 3° AOA below the maneuvering tone. At greater than 0.8 IMN wing drop may occur 3° AOA below maneuvering tone. The severity of wing drop increases as Mach number increases and as altitude decreases. If wing drop occurs, flying qualities can be improved by reducing AOA.

 

WARNING

Transonic wing drop may occur at angles of attack below the maneuvering tone. Extreme care should be exercised at elevated AOA when maneuvering near ground level above Mach 0.8.

.

-------------------------------------"

 

 

Here there is no mention of aileron input, neither is it a comlete departure from controlled flight. As I understand the text there should be a tendecy for a simple uncommanded roll to one direction, when pulling back the stick hard enough (no aileron input) while flying at high mach numbers.

 

 

In the following track I actually go over Mach 1, then pull full aft stick (clean aircraft diving from 10000 m ) and there is no tendency of uncommanded roll or any other adverse effects.

 

 

Again I am simply relying on your text from the NATOPS, nothing more.

AV8_supersonic.trk

[HWasp]

Here are the other relevant parts of the NATOPS:

 

11.3.1 Critical Mach

 

The free--stream Mach number at which there are first signs of local sonic airflow on the wing and hence shockwaveformation.Critical Mach (Mcrit) is measured in 1g flight.



This occurs on the AV--8B at 0.82 to 0.85 IMN (indicated mach number).

 

11.3.1.1 Shock--induced Flow Separation

 

Loss of smooth (laminar) airflow over the wing can occur due to shock wave formation if the airflow over the wing is allowed to become supersonic.

 

A1-AV8BB--NFM--000ORIGINAL

 

11-311.3.1.2 Maneuvering Mcrit

 

Although Mcrit is measured in 1g flight, the effect of shockwave formation can occur at Mach numbers below Mcrit due to AOA on the wing. The increasing AOA accelerates the airflow across the top of the wing so that it becomes supersonic at an IMN less than the 1 g critical Mach. In the AV--8B this effect becomes apparent when maneuvering above 0.78 IMN

 

 



11.3.1.4 Force Divergence Mach Number/Drag Rise



The indicated Mach number above critical Mach, which produces a sharp change in the drag coefficient (boundarylayer separation due to shock wave formation ) is termed the “force divergence” Mach number. It is also referred toas “drag divergence” and occurs on the Harrier at approximately 0.87 IMN and results in buffet, trim and stability changes, and a decrease in control surface effectiveness

 

If the buffet is quite severe or prolonged, structural damageor failure may occur when this boundary layer separation is experienced on the wing due to shock wave formation.There will be a loss of lift and a subsequent loss of downwash aft of the affected area. When shock induced separationoccurs symmetrically at the wing root the decrease of downwash aft of this area results in a decrease in downwashon the horizontal stabilator and thus we notice the aircraft’s tendency to “tuck”. If the wings shock unevenly due tophysical shape differences or sideslip, a rolling moment will be created in the direction of the initial loss of lift andwill contribute to “wing drop” and control difficulty. If either of these conditions occurs reduce the throttle anddecelerate the aircraft below 0.78 IMNwhile avoiding any large control inputs