DCS: AJS-37 Viggen Discussion

[renhanxue]

For everyone discussing the split-S it is not necessary the case that the pilot in this case made a full split-S. What was described was a half-roll and hard pull towards the sea (not necessarily to vertical), when levelling out he more likely made another half-roll before levelling out (something I find more likely). In other words I do not think he did a complete split-S. Someone translated "halvroll" to split-S which is not 100% correct. "Halvroll" is only the first maneuver in a split-S, in this case rolling to inverted.

 

 

That was me, and I'm pretty sure I'm right. "Halv roll" sounds like it would mean just a 180 degree roll, but that's not what it actually refers to in military Swedish (dunno about civilian acrobatic flying). It really does refer to a split S. See for example these two pages from the J 35F SFI, which show that the maneuver does involve rolling inverted and pulling down.

 

 

 

As you can see, in the Draken (which accelerated incredibly quickly in a dive and also had problems with generating enough force on the elevons at high loadings) entering a split S was normally (in peacetime) forbidden at any speed at altitudes below five kilometers. See also this diagram though, which shows a minimum required altitude of about 1500 meters if you're pulling 7 G through the entire maneuver:

 

Edited June 27, 2016 by renhanxue

[Cobra847]

Next to last research trip was conducted today, with the great JA-37Di at Graz-Thalerhof.

 

Unfortunately a bit different than our AJS-37; but still a great tool (amongst others) to ensure maximum graphical accuracy.

We were finally able to solve some cockpit accuracy issues due to lack of reference (on major cockpit parts, nonetheless!). Canopy elements can be a real PITA to get good reference for.

 

Progress is very strong, looking forward to being finally done!

Edited June 27, 2016 by Cobra847

[WARJUNIOR]

Next to last research trip was conducted today, with the great JA-37Di at Graz-Thalerhof.

 

Unfortunately a bit different than our AJS-37; but still a great tool (amongst others) to ensure maximum graphical accuracy.

Progress is very strong, looking forward to being finally done pretty soon!

 

Thanks for the update, Cobra. Looking forward to the viggen being done "pretty soon™".

[Cobra847]

Thanks for the update, Cobra. Looking forward to the viggen being done "pretty soon™".

 

I removed the trademarked quote; just in case anyone gets triggered. :D

[microvax]

Next to last research trip was conducted today, with the great JA-37Di at Graz-Thalerhof.

 

Unfortunately a bit different than our AJS-37; but still a great tool (amongst others) to ensure maximum graphical accuracy.

We were finally able to solve some cockpit accuracy issues due to lack of reference (on major cockpit parts, nonetheless!). Canopy elements can be a real PITA to get good reference for.

 

Progress is very strong, looking forward to being finally done!

 

Next to last means not the last or actually the last ? xD I can imagine the pain, even if you try to get scale of something as simple as an logo from non plain photographs its hard. But 3 dimensional objects, welllll. :D

 

But is progress stronk ? )))

Cant wait to launch thors hammer all over the place ! :D

Will we get the option to load mixtures of MJ1 and MJ2 or only one type of submunitions ?

 

Airfields shall be closed in blueflag by hail of mjoelnirs. ))) Soon. :music_whistling:

[Hummingbird]

That was me, and I'm pretty sure I'm right. "Halv roll" sounds like it would mean just a 180 degree roll, but that's not what it actually refers to in military Swedish (dunno about civilian acrobatic flying). It really does refer to a split S. See for example these two pages from the J 35F SFI, which show that the maneuver does involve rolling inverted and pulling down.

 

 

 

As you can see, in the Draken (which accelerated incredibly quickly in a dive and also had problems with generating enough force on the elevons at high loadings) entering a split S was normally (in peacetime) forbidden at any speed at altitudes below five kilometers. See also this diagram though, which shows a minimum required altitude of about 1500 meters if you're pulling 7 G through the entire maneuver:

 

 

There we go, +1 rep :thumbup:

[Hummingbird]

Next to last research trip was conducted today, with the great JA-37Di at Graz-Thalerhof.

 

Unfortunately a bit different than our AJS-37; but still a great tool (amongst others) to ensure maximum graphical accuracy.

We were finally able to solve some cockpit accuracy issues due to lack of reference (on major cockpit parts, nonetheless!). Canopy elements can be a real PITA to get good reference for.

 

Progress is very strong, looking forward to being finally done!

 

Hopefully you get a tour of a F-14 cockpit sometime too :)

[Skjold]

Thanks for the update Cobra, can't wait for release.

[RaXha]

Next to last research trip was conducted today, with the great JA-37Di at Graz-Thalerhof.

 

Unfortunately a bit different than our AJS-37; but still a great tool (amongst others) to ensure maximum graphical accuracy.

We were finally able to solve some cockpit accuracy issues due to lack of reference (on major cockpit parts, nonetheless!). Canopy elements can be a real PITA to get good reference for.

 

Progress is very strong, looking forward to being finally done!

 

 

Sounds great! We are looking forward to it as well, as you might have noticed! ;-)

[Jaktaz]

Next to last research trip was conducted today, with the great JA-37Di at Graz-Thalerhof.

 

Unfortunately a bit different than our AJS-37; but still a great tool (amongst others) to ensure maximum graphical accuracy.

We were finally able to solve some cockpit accuracy issues due to lack of reference (on major cockpit parts, nonetheless!). Canopy elements can be a real PITA to get good reference for.

 

Progress is very strong, looking forward to being finally done!

 

Where do you go for the research?

[Cobra847]

Where do you go for the research?

 

For the AJS-37 we've used the Viggen simulator at SweSim (http://www.swesim.se/simulatorer/ajs37)

 

The Viggens at Arboga (http://www.jetjournal.net/galerie/image?view=image&format=raw&type=img&id=5932)

 

..and the JA-37Di at Graz-Thalerhof (http://www.rodbearden.com/Europe%202015/Austrian%20Av%20Mus%20Graz/Saab%20JA37DI%20Viggen%2037431%2031-17%202.JPG)

[RaXha]

For the AJS-37 we've used the Viggen simulator at SweSim (http://www.swesim.se/simulatorer/ajs37)

 

The Viggens at Arboga (http://www.jetjournal.net/galerie/image?view=image&format=raw&type=img&id=5932)

 

..and the JA-37Di at Graz-Thalerhof (http://www.rodbearden.com/Europe%202015/Austrian%20Av%20Mus%20Graz/Saab%20JA37DI%20Viggen%2037431%2031-17%202.JPG)

 

 

 

Any reason you have not used the Swedish airforce historic flight AJS 37? :-)

[Cobra847]

Any reason you have not used the Swedish airforce historic flight AJS 37? :-)

 

Are you referring to SE-DXN? We have lots of photos and videos of her, but we didn't really need access to a running Viggen.

[RaXha]

Are you referring to SE-DXN? We have lots of photos and videos of her, but we didn't really need access to a running Viggen.

 

I was just thinking that using SE-DXN for reference when it comes to parts that are hard to get photos of would be a no brainer, but maybe it has been modified somewhat for civilian use? :-) Can't wait to see the final results! :D

[renhanxue]

I was just thinking that using SE-DXN for reference when it comes to parts that are hard to get photos of would be a no brainer, but maybe it has been modified somewhat for civilian use? :-) Can't wait to see the final results! :D

I know I've seen a photo of the SE-DXN cockpit somewhere but I can't find it now. As far as I can remember there were some mods but nothing huge - the emergency instructions text on the flat surface below the HUD was replaced with a translation table between metric altitude and flight levels, and there might have been a civilian GPS unit somewhere too.

[Cobra847]

I was just thinking that using SE-DXN for reference when it comes to parts that are hard to get photos of would be a no brainer, but maybe it has been modified somewhat for civilian use? :-) Can't wait to see the final results! :D

 

Most museum birds are actually very complete, both inside and out- so as long as it's a Viggen, a static display works just fine. :)

 

It's also way easier to crawl all around a cockpit if it's static and less sensitive than something like SE-DXN

[RaXha]

Most museum birds are actually very complete, both inside and out- so as long as it's a Viggen, a static display works just fine. :)

 

 

 

It's also way easier to crawl all around a cockpit if it's static and less sensitive than something like SE-DXN

 

 

 

True! Wouldn't want to flip all the switches when trying to get that perfect shot of the canopy locking mechanism! ;-)

[Silver_Dragon]

But LN team has help from Viggen real pilots for AJS module?

[Cobra847]

But LN team has help from Viggen real pilots for AJS module?

 

We do, but it's not very necessary. The aircraft is incredibly well documented.

 

Since the aircraft has not been in service for a long time; you run into a lot of "forgetful pilot syndrome"-- where recollections do not match documentation.

[JanTelefon]

We do, but it's not very necessary. The aircraft is incredibly well documented.

 

Since the aircraft has not been in service for a long time; you run into a lot of "forgetful pilot syndrome"-- where recollections do not match documentation.

 

Except when they recollect that it was an awesome plane... That is still accurate. :D

[Cobra847]

Except when they recollect that it was an awesome plane... That is still accurate. :D

 

Those are the best types of recollections, the ones starting with:

 

"..this one time.."

[RaXha]

Those are the best types of recollections, the ones starting with:

 

 

 

"..this one time.."

 

 

 

"..at band camp.."

 

No? XD

[boopidoo]

@renhanxue

Thanks, I stand corrected however I still doubt even a clean SH37 could safely perform a Split-S at those speeds at 500m. The Viggen was a very good aircraft in many aspects but it wasn't really super agile. :)

[renhanxue]

@renhanxue

Thanks, I stand corrected however I still doubt even a clean SH37 could safely perform a Split-S at those speeds at 500m. The Viggen was a very good aircraft in many aspects but it wasn't really super agile. :)

I don't disagree. Unfortunately I can't find the SFI section that would settle the matter (there's probably a turn performance chart that shows exactly how much altitude is needed).

[CoBlue]

If Viggen could do an vertical split-S from 500m & recover at 100m easily (as per article).

You guy's don't think this astonishing maneuver would be a given part of every Viggen flight display?

Are there any videos confirming this maneuver?

 

"EDIT: the speed in the split-S from 500m was 550-700km/h, according to the pilot."

Edited June 29, 2016 by CoBlue