J-20... The New Generation Fighter III

Originally Posted by Bltizo

What exactly is the use of lenses in the first place on hmds? I always assumed it was to do with night vision projection, with the actual info projected onto the visor..? Hmm I don't know

My guess is collimation of the beam (making the light rays parallel), so that the pilot perceived the projection to be at infinite distance.

Originally Posted by Bltizo

What exactly is the use of lenses in the first place on hmds? I always assumed it was to do with night vision projection, with the actual info projected onto the visor..? Hmm I don't know

But I think we can be confident j-20 will feature an advanced hmd. My hope is they have a refit in place for older fourth gen aircraft like jhmcs, to be put on existing helmets.

This is an example of what kind of information you will find on a relatively advanced HMD in service today. So you are looking at things like the Israeli Dash 2 or US JHMCS.



The following is a good guide showing what all the information represents.



So basically it projects all the information you would normally expect to see on you HUD onto the lenses in front of your eyes so you have access to all that data no matter where you are looking.

It is only with the F35 HMDS that you are getting towards the level you are suggestion, with live video from things like the IRST feeding directly into your HMD and projecting over the real world. As this final image shows.



As with the HUD, the bigger the lenses, the better, as you can put more information onto it without it all getting jumbled up. So the very small lense you see on early J7 HMS will probably only be able to give very basic and limited information.

I am hoping that the HMD being developed is more on par with the F35's HMDS rather than the JHMCS, and the choice of going for dual lenses instead of just the single one, as well as the greenish tinge to the lenses in that picture might support this, but there is really too little information to say conclusively yet.

The technology is not all that difficult as you have basically the same thing, if not more advanced, being developed for next generation smart phones. The tricky part is making the thing small and light enough to fit in a helmet without risking it snapping the pilot's neck when he pulls 9Gs.

Originally Posted by xywdx

Fairly certain that's a girl, so it's not Luke, maybe Leia Skywalker then?

Yes you're right, it's Leanna Skywalker.

I need the original photo

Originally Posted by Deino

I need the original photo

There you go buddy.

Edit,

Humm, looks like imageshack is doing its auto-rescaling tricks again.

Drop me a PM if you want the original (1019 x 714).

There is an option to not rescale under the upload bar for imageshack.

Originally Posted by plawolf

There you go buddy.

Edit,

Humm, looks like imageshack is doing its auto-rescaling tricks again.

Drop me a PM if you want the original (1019 x 714).

Does anyone know if the pitot tube will be removed on actual production aircraft? I'm sure it adds significant RCS to the J-20.

Originally Posted by kwaigonegin

Does anyone know if the pitot tube will be removed on actual production aircraft? I'm sure it adds significant RCS to the J-20.

If you're talking about the massive one air data probe, that will only present on initial prototypes and test aircraft. That massive thing and the computers behind it takes up the space where a radar would sit as well.

If you're talking about the smaller tubes further down the nose, they will likely be on the production aircraft. Production F-22 and 35 have pitot tubes too.

thanks B.. yeah I was actually refering to the air probe not the pitot tube.

Originally Posted by no_name

There is an option to not rescale under the upload bar for imageshack.

The mods might want to clarify this but I believe this forum automatically reduces oversized images to 800x561. I believe I read something of that from one of the Webmaster's posts. Which is why no one saw the skirt and heels I mentioned standing in the middle of the ramp of a Varyag pic. These days in SDF if I see a pic in here first, I have to go looking at other sites for the original sized image.

Originally Posted by Bltizo

If you're talking about the massive one air data probe, that will only present on initial prototypes and test aircraft. That massive thing and the computers behind it takes up the space where a radar would sit as well.

If you're talking about the smaller tubes further down the nose, they will likely be on the production aircraft. Production F-22 and 35 have pitot tubes too.

It must be possible to determine the dynamic pressure from an array of static pressure ports distributed over the forward ~third of an aircraft. You have to calibrate the measurement for aircraft attitude, Mach number and curved flight and if you lose you computer you're as helpless as those pilots in Air France 447 over the South Atlantic two years ago.
I'm not sure that it will be worthwhile.

Originally Posted by Lion

It's not about realistic anot. It's already become a must. PLA Top brass know that to close the gap with US in air supremacy. It is the IOC date and no other. It is further than that, it serves no purpose as US will probably have a block II F-22 or more advance in 2018-2020..

I believe the one we see at Chengdu in the eyes of the public is not the latest J-20 development. The on at chengdu is just for public consume. Who the hell will test a latest state of art fighter jet in a crowded city and in the eyes of so many people?

The real test will probably conduct in inner Xi an test center, far away from public test. As for what kind of stages, it has reached. I can't answer but will be far more advance than what we seen in chengdu.

Just like J-10B, we have just seen J-10B appear with WS-10 then the top brass talk about equip PAF with these birds next year without even mentioning whether seeking Russia approval for re - export of engine. It's very clear, the engine for PAF will be WS-10. But we just seen it tested on this 05 prototype in the July - August date. You can imagine actually, how and earlier they have already tested J-10B with WS-10 trial since next year they are confident to equip PAF or PLAAF with it. Must early than what we have seen with 05 prototype.

Xi'an is a even bigger city, even if not more populated.....

Hey guys, why haven't many of you rushed to digest the piece I had posted days ago? That would have told you so many things about the stages at which the J-20 and J-10 have been! You would not have had to guesstimate like bunch of blind people trying to figure out how an elephant is like by touching and groping it all the places... :-)

I know I know, we just like the fun of theorizing, arguing, debating, and of playing aircraft engineers, disgners, analysts, etc. etc.

Hehe, I think the above should go to Keypublishing, BR, and their likes. In that case, I should add:

Learn some Chinese, guys! If by any chance China won't implode for another 10 years, you may find your Chinese helpful when you want to make some easy Yuan in that commie land.

Originally Posted by Player99

Hey guys, why haven't many of you rushed to digest the piece I had posted days ago? That would have told you so many things about the stages at which the J-20 and J-10 have been! You would not have had to guesstimate like bunch of blind people trying to figure out how an elephant is like by touching and groping it all the places... :-)

I know I know, we just like the fun of theorizing, arguing, debating, and of playing aircraft engineers, disgners, analysts, etc. etc.

Hehe, I think the above should go to Keypublishing, BR, and their likes. In that case, I should add:

Learn some Chinese, guys! If by any chance China won't implode for another 10 years, you may find your Chinese helpful when you want to make some easy Yuan in that commie land.

Be mindful of your tone of your reply. No abusive language of other people's country! Readers might think you post racist comments. Cheers!