Russian hud why no flight path vector?

[monotwix]

Pardon the double post, a little pushed for time... this is actually an excellent retrospective on the progress of the Russian avionics industry since the 1950s! Really cool stuff!

 

http://www.aviationtoday.com/av/military/Russian-Airborne-Computers_12840.html#.UJg1zMXA_h4

 

 

That was written in September 2001 about something from decades ago and to build a MIG-31 or TU-160 avionics model from that data is .. is .. OO0.

Double O zero.

[aaron886]

What the...?

[Alfa]

Link em if you've got em! Location escapes me, but I was reading a technical report on the F/A-18's HUD and it's suitability for escape from extreme attitudes.

 

I could be wrong, but the report in question seems to be the one I have attached to this post.

 

If so I think you are missing a couple of points. The report investigates the usefulness of the HUD versus back-up instruments(the ADI) when recovering from "unusual attitudes" in the F-18 - more specifically whether initial test studies(using modified test instrumentation) leading to the recommedation of using the ADI would "hold water" in an actual operational environment.

 

So it deals with the HUD/instrument layout of the F-18 specifically and as I read it, the conclusion is not conclusive :) - i.e. both methods performed equally "well" and that a bigger issue was with attempting to use both at the same time instead of picking one and sticking with it.

 

While the study shows that the HUD "does the job" as well as the back-up ADI, it also mentions that one of the reasons for this might have to do with the position of the ADI in the pit(low and off-set to the right).

 

Seems its combination of measures is extremely effective and of course quite standard among western displays.

 

I don't really see how you can arrive at that conclusion - one of the closing comments by the author:

 

"Finally, the author would like to encourage a discussion

on the somewhat disillusive finding of a failure

rate of 29% and 27%, respectively, in one of the world’s

most sophisticated fighter aircraft."

 

Anyway, I think the subject and findings of this report is pretty far detatched from the topic of this thread - except perhaps that pilots perform best when relying on the instrumentation they are used to through their training and therefore feel most comfortable with.

[monotwix]

What the...?

 

 

I had a bad habit looking at the HUD in this track, there’s nothing to see through the HUD but I kept looking, it’s because one of those things where some pilots are more proficient with digits and others are more proficient with dials.

In the end it’s easier to fly looking down at the engine needles than observing stars if you like. I didn’t like the circles on final though.

IFR attack.trk

[marcos]

From an engineering-style control perspective, closed-loop is better than open-loop. There are many degrees of open and closed loop but the Su-25T system is broadly open loop. The HUD tells you left or right and right and wrong but it does't tell you how much left or right, or how right or wrong you are, so the drive cannot be proportioned to the error. As such, from a purely analytical perspective, the drive will tend to lead to more overshoot and/or a slower response time.

[ФрогФут]

From an engineering-style control perspective, closed-loop is better than open-loop. There are many degrees of open and closed loop but the Su-25T system is broadly open loop. The HUD tells you left or right and right and wrong but it does't tell you how much left or right, or how right or wrong you are, so the drive cannot be proportioned to the error. As such, from a purely analytical perspective, the drive will tend to lead to more overshoot and/or a slower response time.

 

Su-25T symbology is ED fantasy and so cannot be used as reference. Steering circle on real planes works fine.

[CoBlue]

... you're going to be looking at your HUD during 'close combat'? ... interesting :)

In certain cases yes... to establish lead on/off angle to the target by FPV...I know exactly where I'm headed:smilewink:

 

There have been several researches on that, including USA.

 

See screenshot from A-10C. Does not really help with the crosswind. Don't think, that idiots work on the other side. Here we have bad viisibility very often (compared to US), and there is no much use of velocity vector during landing in poor visibility and strong crosswind.

I have to disagree: FPV is a tremendous help during landing in poor visibility and strong crosswind...why wouldn't it? It's even used in commercial jets because of the advantages in those precise conditions....

Russian engineers are brilliant.....that's why I wanted an answer, presumably by one of them on the FPV matter.

All in all I think that FPV makes life easy:D

Edited November 6, 2012 by CoBlue

[ФрогФут]

to establish lead on/off angle to the target by FPV...I know exactly where I'm headed

I may say, that probability of the FPV getting below HUD FOV in this situation is very high.

I have to disagree: FPV is a tremendous help during landing in poor visibility and strong crosswind...why wouldn't it?

Crosswind (5-7 m/s) is shown on my screeenshot. It is off the HUD. In poor visibility you just don't see, where to put it and placing it on some HUD symbol does not differ from steering circle much.

Of course if the FPV is off the HUD it's no good to the pilot, but that doesn't remove the viability of the other instruments of course. You might be interested to know that the FPV/VV/FPM can usually be "caged" to the center of the HUD so that it can continue to provide usable descent angle information.

And? I can still get that info, without it.

Edited November 6, 2012 by ФрогФут

[GGTharos]

If your adjustments are so minute that both target and FPV are in your hud, you're not even really maneuvering much; and if you really need to see the FPV to fly in relation to your target then you have no sense of relative aircraft maneuvering in BFM.

 

In certain cases yes... to establish lead on/off angle to the target by FPV...I know exactly where I'm headed:smilewink:

[aaron886]

And? I can still get that info, without it.

 

And you won't get it from other instrumentation. That's not an argument against the value of an FPV.

[monotwix]

What other instrumentation could possibly top FPV? Hmm.

[vanir]

A somewhat related anecdote, at least of my point, is when I first started flying lomac I tried ILS and crashed constantly, which was disconcerting since I was fairly practised with other warbird flight sims and the jets seemed to have much more control at landing speeds than things like Spits and Messers (admitedly higher landing speeds, but still more control and able to handle it safely).

I got so fed up I decided to ignore the cues and just land visually like I do in a Messer. Had no problem with good soft landings, first time, every time.

I get a little paranoid in bad weather of course because I dread the ILS landing, but if I can see I do much better using my own judgement than being led by the nose by automatic cues that are so comprehensive you're supposed to respond with controls to HUD cues and not what's going on beyond the HUD and your own judgement.

 

There is a point I find where cues become clutter, don't you think it's a bit redundant to have a HUD that displays flying instructions amid all else you have to monitor? ILS is one thing and I can understand the necessary evil obviously, but I really don't like the US HUDs in FC2 personally, or the ergonomics. I find them worse than the Russian ones, annoying and in my way. The Russian ones I leapt into and they worked with me going in cold, very very easy to fly well and transfer skills, I found.

[aaron886]

I do much better using my own judgement than being led by the nose by automatic cues that are so comprehensive you're supposed to respond with controls to HUD cues and not what's going on beyond the HUD and your own judgement.

 

I definitely don't want to sound rude or condescending, but you can't really make that assessment unless you are a capable pilot who is using the system properly. To a real pilot, all of the information presented on a western HUD is useful and usable in its proper place. A good system is going to look complicated if you don't possess the skills to use it properly in the first place. Being able to determine the correct use of that information is how a pilot makes his money.

 

I can read and assimilate the usable information presented by a western HUD or a Russian HUD. I find the western display symbology to be superior in most cases, particularly the pitch "ladder" system, and the FPV. I do like the scaling of airspeed and altitude on a Russian HUD, though, for example.

[monotwix]

That is nice example for example.

Do you like it?

 

 

Sense of attitude

[ФрогФут]

And you won't get it from other instrumentation.

Even on A-10C i have numeric descent angle on the HUD.

It is very bad habit to learn flying with FPV. It would be very difficult to fly without it due to failures, especially in poor weather conditions. And if you learned to fly without it you won't need it much. It is still convenient instrument to correct yourself with in some cases, but you won't look at it much.

Edited November 7, 2012 by ФрогФут

[aaron886]

Even on A-10C i have numeric descent angle on the HUD.

 

That's a rate, not an angle.

 

 

And if you learned to fly without it you won't need it much. It is still convenient instrument to correct yourself with in some cases, but you won't look at it much.

 

I learned to fly without it. I routinely fly without one outside of simulators. That doesn't keep it from being a valuable instrument that I would use heavily... it's another piece of information.

[Reaper26]

That's a rate, not an angle.

 

How about degrees...i.e. angle...

Edited November 7, 2012 by Reaper26

[Sov13t]

threads/discussions like these make this forum awesome! :thumbup:

[marcos]

It is very bad habit to learn flying with FPV. It would be very difficult to fly without it due to failures, especially in poor weather conditions.

Well I think that's as good as an inadvertent admission that FPV is better, if not having FPV makes things more difficult.

[VAOZoky]

In A2A fpv is useless, in high-level A2G fpv is useless, in low-lelel A2G is good but far from essential. In night or fog conditions fpv is useless too!

[ФрогФут]

Well I think that's as good as an inadvertent admission that FPV is better, if not having FPV makes things more difficult.

What is said meant, that it would be very difficult for you to fly by instruments in case of HUD failure or poor weather conditions, IF you learned and used to flying by the FPV only.

That's a rate, not an angle.

There are both on A-10C HUD.

PS This is how my HUD usually looks like.

Edited November 7, 2012 by ФрогФут

[marcos]

What is said meant, that it would be very difficult for you to fly by instruments in case of HUD failure or poor weather conditions, IF you learned and used to flying by the FPV only.

Well I think that's the point. You don't actually have to learn FPV, it's just intuitively obvious.

[GGTharos]

No, the FPV is an additional, helpful datapoint in some situations. It is not, nor will it ever be, a replacement for instrument flying skills.

 

Well I think that's the point. You don't actually have to learn FPV, it's just intuitively obvious.

[aaron886]

What is said meant, that it would be very difficult for you to fly by instruments in case of HUD failure or poor weather conditions, IF you learned and used to flying by the FPV only.

Of course... but that's not the point. It's a tool in the toolbox.

 

There are both on A-10C HUD.

 

There is no indication of angle of descent on that HUD other than the FPV. Pitch angle, yes. Descent rate, yes. Combined, you can determine information required for instrument flight, but an FPV displays it better.

 

Well I think that's the point. You don't actually have to learn FPV, it's just intuitively obvious.

You do have a point, in that an FPV is an instrument that makes intuitive sense.

[ФрогФут]

See screenshot.

Of course... but that's not the point. It's a tool in the toolbox.

These are soviet aircraft we are talkting about. And FPV wouldn't be a tool with soviet symbology. It would be even a possible cause for accidents with the symbology used on those (and some new) planes. And RuAF MiG-29/Su-27 still fly well even without it.

Edited November 7, 2012 by ФрогФут