DCS: AJS-37 Viggen Discussion

[Snail]

I already was afraid that I needed upgrading. This is a perfect excuse :-)

[Tackle]

I hope that answers some of your questions.

 

Great Info as always!

Thank you very much!

 

Is the tailnumber part of the serial, or did they just start from 01 for each Division? And was there a maximum/ typical number of airframes per Division?

[renhanxue]

Squadrons were dimensioned for keeping one flight of four aircraft in the air or at highest readiness 24/7. The flight of four was the normal tactical unit, but for most missions the squadron would operate two flights at once. This required at least 16 pilots, and there were 108 AJ 37's manufactured for six squadrons, which gives 18 airframes per squadron (so really, 16 plus two spares to account for crashes and other write-offs during the service life of the aircraft).

 

I think tail numbers were initially assigned based on the last digits in the aircraft's serial number but that soon led to conflicts and aircraft were reassigned between wings and got new numbers and so on, so that convenient relationship was often broken. Tail numbers were assigned on a wing level btw and there's no way of telling which squadron an aircraft belonged to based on the tail number. Numbering was not sequential either.

 

Example: the only flying AJS 37 today is "Gustav 52" (7-52), which has serial number 37098 (one of the last AJ 37's manufactured). No relation in that case and I know for a fact that F7 did not have all tail numbers between 1 and 51 assigned.

Edited November 6, 2016 by renhanxue

[mattebubben]

Well they dont start from 1 in a Division or even wing but i dont know as they dont always seem to match the Serial numbers as shown in the link below they often match the serial (atleast early on) but not always especially after having been transferred to a new division/wing the number might be changes so it no longer matches the serial.

 

And the normal number of aircraft in a Division was 8-12 aircraft with some times a few more + spares etc according to wiki.

(Edit: see Ren got there first with more complete info)

 

And for those interested the Serial ranges for the Different Viggen variants were as follows.

 

AJ 37 serial numbers 37001–37108

JA 37 serial numbers 37301–37449

SK 37 serial numbers 37801–37817

SH 37 serial numbers 37901–37927

SF 37 serial numbers 37950–37977

 

And there is also an interesting Wiki page

(in Swedish but i think it will still be interesting)

 

It details the info about the different aircraft and shows pretty much all the data on the different serials.

 

When they where completed when they were Scrapped or if/when they crashed as well as if they were upgraded and if so when they were upgraded.

 

https://sv.wikipedia.org/wiki/Lista_%C3%B6ver_Saab_37_Viggen

 

Some Explanations first to let you guys more easily understand / navigate that page.

 

Flygplannummer is the serial code of the aircraft.

 

Godkänd means Accepted as in that is the date the aircraft was accepted by the airforce.

 

Kasserad means condemned as in when the aircraft was condemned / written of.

 

Haveri is the term used for a crash/accident that left the aircraft destroyed.

 

Bas/kod is Base/code and it shows the Codes (tail number) the Aircraft used as well as where it did so,

and if an aircraft has many it tells at what time it used what number.

 

For example Serial nr 37006 has 3 sets of codes,

FC-16, 7-06, 15-06 the first code FC-16 means that it was used by the Testing center to do tests at first and during that time it carried the Tail number 16,

 

7-06 means that it was delivered to F7 where it carried the Tail number 06 and then finally it was transferred to F15 where it also carried the number 06.

 

The next section determins if the aircraft had been upgraded or not and to what version if it was upgraded.

 

And then lastly you have Anmärkning meaning Observation/notes where it will state what happened to it,

If it was scrapped or sent to a museum etc or if it crashed where it did so.

 

And then there might be a Picture of the aircraft in question.

 

If anybody has anymore questions or need translations from something on that page feel free to ask.

Edited November 6, 2016 by mattebubben

[Tackle]

@renhanxue

@mattebubben

Thanks again, exactly what I was looking for!

[theOden]

I already was afraid that I needed upgrading. This is a perfect excuse :-)

Are you by any chance a horribly old Dutch e-pilot?

:D

 

/theOlden

[Snail]

Are you by any chance a horribly old Dutch e-pilot?

:D

 

/theOlden

 

............... guilty as charged......... ;)

[theOden]

Bingo.

I would say we now have the, by far, biggest Viggen fan onboard the hype train haha.

Great to see you here Snail.

Check PM :)

[Snooze]

And there is also an interesting Wiki page

(in Swedish but i think it will still be interesting)

 

It details the info about the different aircraft and shows pretty much all the data on the different serials.

 

When they where completed when they were Scrapped or if/when they crashed as well as if they were upgraded and if so when they were upgraded.

 

https://sv.wikipedia.org/wiki/Lista_%C3%B6ver_Saab_37_Viggen

 

Some Explanations first to let you guys more easily understand / navigate that page.

 

There´s an awfully lot crashes reported on the 37-system even though it was a rather simple and trust-worthy aircraft to fly! But the operational behaviour of context really seemed to put pilots on the edge way to often.

[Snail]

Bingo.

I would say we now have the, by far, biggest Viggen fan onboard the hype train haha.

Great to see you here Snail.

Check PM :)

 

That's too much honour, IF it's an honour ;)

 

I read the PM: we have a plan :-)

[Pocket Sized]

The Ground Proximity Warning System (GPWS) warns the pilot when coming too close to the terrain.

 

The GPWS is a warning system and must not be used for guidance

 

I would like to make a complaint relating to the bolded text from the JA-37 manual.

 

Please do not post false/misleading advice on the forums, thank you.

 

:megalol:

[Skjold]

There´s an awfully lot crashes reported on the 37-system even though it was a rather simple and trust-worthy aircraft to fly! But the operational behaviour of context really seemed to put pilots on the edge way to often.

 

That is due to a number of factors:

 

1. In the early years i think there were some technical issues with the platform which was later resolved. Don't have the details, Renhanxue or Mattebubben probably does.

 

2. Low flying doctrine, most sorties in the AJ would have been done just above tree top level or sea level, this is especially dangerous over the baltic (the main domain for the AJ 37) due to Spatial disorientation.

 

3. Dogfight training, Sweden had a policy of having dogfights "as close to the real thing as possible" which in return made them more dangerous. This mostly applies to the JA 37.

 

4. Road base doctrine, not the easiest thing in the world to operate from roads.

 

https://youtu.be/KEyY2Q37sYQ?t=3m34s

 

Service ceiling of the Viggen :music_whistling:

[Snail]

Service ceiling of the Viggen :music_whistling:

 

Let me guess,... 300 feet? 450 at the most? :pilotfly:

[mattebubben]

The Viggen did not really have many more accidents then any other aircraft of the same time period that was flown in a similar way,

Flying low and fast regularly is always dangerous and increases the risk by alot compared to flying higher since there are much smaller margins.

 

The most common causes for accidents where pilot errors,

Either Crash on landing/take off,Controlled Flight into terrain (usually over the ocean as it was easy to loose spatial awareness and at speeds of Mach 0.8-0.9 at low altitude even a few degrees of dive and you can be dead before you realize the mistake.

 

The only real accidents that happened due to a problem in the aircraft where the so called "vingbrottshaverierna".

 

In the 70s during early service there were 3 accidents due to a fault in the wings that caused one of the wings to snap during maneuvering (Usually during a rolling maneuver with the afterburner engaged)

All of the 3 pilots made it out alive due to the automatic system

(that caused the pilots to be ejected when the aircraft broke apart).

 

The Fault if it remember correctly (im sure Renhauxe will supply us with more complete information) was due to the fact that one of the wing spars was too weak and prone to metal fatigue.

(and enough weakening could cause it to snap during hard maneuvering).

The First accident happened in 1974 the second in 1975 and 4 days later the third,But after those 3 accidents and having located the problem was fixed and that type of accident never happened after that.

 

Over all the Viggen was not a particularly dangerous aircraft,

With 329 aircraft made of all variants and serving from 1967

(first prototype flight) to 2005 (last Viggen left airforce service) only 54 aircraft crashed of were damaged beyond repair with only 17 pilots dying.

 

And during this time they flew very often (most aircraft had a very high number of flight hours) and very intensely with high speed low level flight and intense practice dogfighting being common practice.

 

Yes it resulted in some accidents but on the other hand it also resulted in Sweden having some of the best combat pilots around who were respected both in the west (from practice encounters and Squadron Exchanges) and in the east from the Russian,Polish and East German pilots that often encountered them in the skies over the Baltic sea.

 

And overall Sweden and the Viggen had no higher loss statistics then other western airforces (if number of aircraft and flight hours etc are taken into account).

 

 

And also for those interested i have another link. (In Swedish as well sadly)

http://www.svfplhist.com/index.htm?s=37/37hav.htm

 

This page lists all the Viggen Accidents and crashes (for all the variants)

as well as including info from the crash investigation report and sometimes pictures etc.

 

http://www.svfplhist.com/index.htm?s=37/37hav.htm

This is the page for the first of the accidents due to the wing problem and includes some nice pictures / illustations.

 

I might translate 1 or 2 of these tomorrow if i have the time.

[Pocket Sized]

All of the 3 pilots made it out alive due to the automatic system

(that caused the pilots to be ejected when the aircraft broke apart).

 

Wow. Y'all weren't kidding when you said the Viggen was ahead of its time!

[mattebubben]

Wow. Y'all weren't kidding when you said the Viggen was ahead of its time!

 

Yea when the Viggen entered service it was very advanced for its time and proved to everybody that it was an advanced and capable aircraft that was very respected in both the West and in the East.

 

When the AJ 37 entered service in the early 1970s it was modern and very capable

(and in the Anti-ship role it was probably one of the best aircraft available at the time)

and then when the JA 37 entered service in 1980 it proved to be a very capable and effective fighter that had some unique systems and features (like the ability to slave the Cannon to the Autopilot having the aircraft steer itself to a proper gun solution if you had a radar lock) as well as getting a complete Fighter-Fighter Datalink many years before most other nations / aircraft.

 

 

For example one thing that always seemed strange to my mind when it comes to the attack/recce variants (AJ37/SH37/SF37) is that despite the way they were meant to be flown (Very high speed very low altitude) they did not have an Audio or Visual warning system for low altitude or imminent ground collision.

 

The later Ja 37 Fighter Viggen apparently had such a system and as such was safer to fly at low altitude (Despite that it did so less then the AJ 37 did).

 

This is one factor that contributed to some of controlled flight into terrain accidents so such a system would have saved lives and i find it strange that it did not have such a warning system from the beginning or never had it retrofitted (where as the Fighter variant had it when it entered service).

 

On a side topic (that also mentions this problem)

im certain that this has been linked on this thread before (90% sure)

but il do it again since there are plenty of new people in the thread and it was many many pages ago.

 

This is an Interview (in english) with a Viggen pilot,

he flew mostly the Ja 37 but had stick time with all variants and he answers questions both about the Viggen as a whole but also about the different variants.

 

https://www.milavia.net/specials/iv_viggen/

Edited November 7, 2016 by mattebubben

[MiG21bisFishbedL]

Are you by any chance a horribly old Dutch e-pilot?

:D

 

/theOlden

 

wut meenz b, though

[MYSE1234]

For example one thing that always seemed strange to my mind when it comes to the attack/recce variants (AJ37/SH37/SF37) is that despite the way it was meant to be flown (Very high speed very low altitude) it did not have an Audio or Visual warning for low altitude or imminent ground collision

 

They actually do have a warning system.

The lamp left of the radar screen starts to flash at 5Hz 7s before the calculated impact time. The hud also starts flashing, in most modes.

There's a whole segment dedicated to it in "SFI AJS37 del 1" on "flik 23".

 

Image from the manual.

Edited November 7, 2016 by MYSE1234

[mattebubben]

They actually do have a warning system.

The lamp left of the radar screen starts to flash at 5Hz 7s before the calculated impact time. The hud also starts flashing, in most modes.

There's a whole segment dedicated to it in "SFI AJS37 del 1" on "flik 23".

 

Ok so its just an Audio warning that is lacking?.

 

I must have missed those pages in the manuals as i think i have read most of them =P.

 

I based my comment mostly on some pilot statements (including from the interview that i linked in that post).

 

Thank you for the correction =).

 

Still feel like they should have included an audio warning as the later fighter variant had since visual cues are much easier to miss during flight (especially if focusing on some other task) then an audio warning is,

But it sure is better then nothing.

Edited November 7, 2016 by mattebubben

[MYSE1234]

Yeah, seams like it's only visual, can't find anything about there being any sort of audio warning.

[Goblin]

Perhaps a slight digression, but as we are talking about Viggen accidents, this one is special.

http://www.svfplhist.com/37/37hav032.htm

Simulated naval attack, birdstrike and hitting the sea surface. The pilot was ejected but didn't survive. He was found without his helmet...

 

A few months ago, a guy shows up on a Norwegian Facebook group where I'm a member, showing pictures of what is clearly a SwAF pilot helmet. He found this on the southern shores of Norway, in the -70ies, as a kid. He recently found it again and started thinking that it most likely had a grim story to tell.

As it turns out, it was the helmet from the accident mentioned above. The helmet was returned to the squadron at F7, to which the pilot belonged. I know the Norwegian media is on the case, so there will most likely be some sort of coverage, eventually.

Edited November 8, 2016 by Goblin
Corrected the link

[Sim Flyer]

Perhaps a slight digression, but as we are talking about Viggen accidents, this one is special.

http://www.svfplhist.com/index.htm?s=37/37hav.htm

Simulated naval attack, birdstrike and hitting the sea surface. The pilot was ejected but didn't survive. He was found without his helmet...

 

A few months ago, a guy shows up on a Norwegian Facebook group where I'm a member, showing pictures of what is clearly a SwAF pilot helmet. He found this on the southern shores of Norway, in the -70ies, as a kid. He recently found it again and started thinking that it most likely had a grim story to tell.

As it turns out, it was the helmet from the accident mentioned above. The helmet was returned to the squadron at F7, to which the pilot belonged. I know the Norwegian media is on the case, so there will most likely be some sort of coverage, eventually.

 

If you hear anything more about that media coverage please also post it here.

[Mjau]

Perhaps a slight digression, but as we are talking about Viggen accidents, this one is special.

http://www.svfplhist.com/37/37hav032.htm

Simulated naval attack, birdstrike and hitting the sea surface. The pilot was ejected but didn't survive. He was found without his helmet...

 

A few months ago, a guy shows up on a Norwegian Facebook group where I'm a member, showing pictures of what is clearly a SwAF pilot helmet. He found this on the southern shores of Norway, in the -70ies, as a kid. He recently found it again and started thinking that it most likely had a grim story to tell.

As it turns out, it was the helmet from the accident mentioned above. The helmet was returned to the squadron at F7, to which the pilot belonged. I know the Norwegian media is on the case, so there will most likely be some sort of coverage, eventually.

 

Ow that bird strike was brutal! :O

 

First the article says the automated system ejected him then later it said he ejected himself? Probably in a split second being half blind from shards of glass in his face? Can't imagine what that must have been like :(

[BravoYankee4]

Here is a summary of the crashes I did a while ago: https://forums.eagle.ru/showpost.php?p=2637207&postcount=726

[renhanxue]

The Fault if it remember correctly (im sure Renhauxe will supply us with more complete information) was due to the fact that one of the wing spars was too weak and prone to metal fatigue.

(and enough weakening could cause it to snap during hard maneuvering).

While I'm flattered, I'll have to confess that I do not actually know everything about the Viggen by heart (yet).

 

You're remembering right though - I went to look it up, and in short, the main wing spar suffered from a design flaw that caused unexpected cracks. After being subjected to sufficient stress over a period of flying it would eventually succumb to metal fatigue and break, which resulted in the entire wing snapping off. After the two crashes in quick succession in 1975 the entire fleet was grounded for months until they figured out what was going on.

 

The pilot in the first crash in 1974 wrote this about the event in a Viggen group on Facebook:

 

Föredrag 2006-02-08 om mitt Viggenhaveri den 11 juli 1974

 

Bakgrund

Kort inledning om min bakgrund fram till 11 juli 1974.

Influgen och krigsplacerad på A 32 Lansen, placerad vid första divisionen/F7 Såtenäs. Tjugotre år gammal och trodde mig ha erfarenhet som skulle visa sig ta ungefär tjugo år att få. Het, entusiastisk och älskade att flyga.

Gift med Catharina och vi väntar vårt första barn i september samma år. Bor på Såtenäs i ett litet radhus med bekvämt cykelavstånd till det hägrande divisionslivet.

 

Vi påbörjade omskolning till Viggen som tredje omskolningsomgång och hade avverkat typinflygningsskedet och var nu sysselsatta med skillnadsomskolning (GFSU:Ä) för att erhålla krigsplacering på AJ 37.

 

Flygning den 11 juli 1974

Den elfte juli var en strålande solskensdag med klar och fin luft. Vår divisionschef, Håkan Högstadius, beslutade att vi denna dag skulle genomföra fem pass avancerad flygning i grupp som ren manöverträning.

Jag var stormförtjust eftersom jag hade lyckan att få två pass under dagen.

Första passet avlöpte normalt och jag såg fram mot mitt andra pass.

Andra passet startade jag efter lunch, där jag tog plats i flygplan ”Gustav 11” (37.011) och ingick i fyrgruppen som flygplan fyra. Gruppchef var Högstadius och min rotechef Anders Eisen. Vi startade från Såtenäs i direkt anslutning till första roten. Steg med EBK zon 2, upp i sektorn vid Vänern och området direkt öster därom. Påbörjade en relativt mjuk uppvärmning med mycket gungor och tunnelrollar för att därefter öka på svårighetsgraden.

Flygningen fungerade bra och jag var nöjd med min insats även om ett och annat kunde bättras på.

 

Efter ungefär tjugo minuters flygtid befann vi oss öster om Vänern mellan Lidköping och Skara. Sikten var underbart obegränsad och vi kände oss säkert allihop som samtrimmade stridspiloter.

 

Det vackra skådespelets perfektionism stördes efter en flack gunga som kom att innebära att fartökningen blev något för snabb och friden störde av en enveten transonicvarning och ilsket lysande varningslampa. Var därför beredd på den upptagning jag visste måste komma för att reducera farten. Upptagningen ansattes mjukt och fint på höjd ca 3 km vid fart M=0.9, och ungefär vid horisontpassage stannade världen för mig.

 

Retardationen och rotationen kom plötsligt och med full kraft. Den enda minnesbilden jag har och någonsin har haft är kraftig retardation och allt svart, hann inte lägga märke till någonting och den enda tanke som passerade innan jag svimmade var att” nu är det kört” för Ola.

Jag vaknade upp i cockpit och registrerade ett fruktansvärt oljud, fortfarande allt svart, utsätts för krafter som är omöjliga att beskriva men uttrycket att sitta i ett skruvstäd passar nog förvånansvärt bra. Dock kan jag inte stabilisera huvudet utan det dunkas mor huven/sargen oupphörligen oavsett vad jag försöker göra. Sikten just nu är ungefär fram till instrumentbrädan men trots ihärdiga försök kan jag inte urskilja ett enda instrument. Förstår inte vad som håller på att hända men inser att jag måste ut. Försöker nå utskjutningshandtagen men armarna orkar inte fram till handtagens läge utan armarna åker rakt ner utmed kroppen. Medvetandet är på väg att försvinna igen och jag upplever för andra gången under denna korta tidsrymd att ”nu är det kört, -igen”.

 

Nästa gång som jag registrerar frisk luft och att jag fortfarande finns kvar är när skärmen löser ut och jag kan se mig omkring och beskåda alla delar som singlar ner mot marken. Strax under mig ser jag benfickorna som har ungefär samma fallhastighet som jag själv.

 

Funderingarna om vad som hänt, kollision, explosion eller vad det nu var, avbröts när jag fick syn på de tre kvarvarande Viggarna som låg och cirklade en bit under fötterna på mig. Förhoppningsvis skulle de snart titta upp och få syn på mig, för nu verkade det som de var mer intresserade av alla delar som regnade ner mot Västgötaslätten och åstadkom bränder både här och där.

Min glädje blev oerhörd när de äntligen tog ut svängen och steg upp förbi mig som ett tecken att de hade fått syn på mig.

 

Jag vinkade som en galning, ren glädjeyra men det var något som inte stämde. Allt kändes normalt förutom att jag inte såg min högerarm när jag vinkade. Konstaterade att armen hade flöjlat och befann sig uppblåst och låst på ryggen. Det var första tillfället som jag examinerade mig själv och kunde konstatera att det fanns inte mycket kvar av flygoverallen, till och med kängorna hade gått sönder, bägge två.

 

Såg inte på höger öga och började sakta känna av att kylan finns en bit upp i luften även under varma julidagar.

Landade i en havreåker på Skaraslätten och trots den mjuka myllan blev jag mörbultad under landningen eftersom jag totalt missbedömde höjden. En bonde på cykel kom till undsättning och strax därpå anlände ambulansen från Lidköping. Personalen där hade haft lunchuppehåll och suttit och tittat på de fyra flygplanen som plötsligt blev tre. De for iväg med ambulansen innan larmet hade initierats och var därför på nedslagsplatsen fem/ tio minuter efter min nedkomst.

 

Kroppen var fullkomligt mörbultad, armen hoppade i led igen vid en oförsiktig rörelse och ambulansen ville inte skjutsa mig till divisionen, dit jag ville, utan transporterade mig till sjukhuset.

 

Jag kom in på sjukhuset och fick där träffa min fru som passande nog jobbade där. Jag vet inte vem som var mest förvånad. Vårt möte avbröts av en tidningsreporter som försökte bryta sig in på undersökningsrummet. När uppståndelsen lagt sig rullades jag upp till min sal där lugnet lägrade sig. Jag stannade på sjukhuset för observation över natten och nästa dag var jag hemma igen, visserligen mörbultad, blåslagen och med nysytt ögonlock men ändock hemma. Kunde naturligtvis inte hålla mig borta från divisionen och dagen därpå haveriplatsen men det är en annan historia.

 

Händelseförlopp

Haveriutredningen visar att vänster vinge lossade och bröt därvid av fenan åt höger, vilket ledde till att flygplanet snabbt sönderdelades i luften, brand i flygplansdelarna och totalhaveri.

 

Utskjutning skedde utan min inverkan, sannolikt genom att stolen lossnade från sina infästningar i durken. Detta berodde troligen på de upprepade kraftiga lastväxlingarna, varefter utskjutningssekvensen aktiverades. Tur vad ju det.

 

Sensmoral

Liten tuva stjälper ofta stort lass och det tar hela livet att bli så skicklig och bra som du en gång trodde att du var.

 

Also from the Facebook group, an article in Ny Teknik from 1976 that explains what happened in detail:

 

 

Edited November 8, 2016 by renhanxue