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View Full Version : Swedish J8A Had No Trim Tabs!



leitmotiv
01-13-2006, 11:06 PM
See splendid collection of photos of in-service Swedish J8As and a preserved one in a Swedish museum:

http://www.avrosys.nu/aircraft/Jakt/108J8.htm

leitmotiv
01-13-2006, 11:06 PM
See splendid collection of photos of in-service Swedish J8As and a preserved one in a Swedish museum:

http://www.avrosys.nu/aircraft/Jakt/108J8.htm

F19_Ob
01-16-2006, 08:02 AM
No worries m8, our J8 doesn't have trimtabs in the sim either.
http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

leitmotiv
01-17-2006, 01:50 AM
Cheers to the boys of F19!

Oleg and Company were right about the trim for pitch: this is how it was done according to Alexander Crawford who wrote the Mushroom monograph on the Gloster Gladiator: "The Gladiator adjusted the trim of the tailplane by means of a large wheel in the cockpit, which when turned adjusted a worm screw in the tail that changed the incidence of the tailplanes." I sent Mr. Crawford another inguiry regarding the lateral trim (no need to ask about rudder trim since there isn't any).

F19_Ob
01-17-2006, 04:58 AM
Thanks for posting that piece.

After your post I was beginning to wonder if my recollections of the gladiator having trim by moving the tailplane was really correct.
I knew it didn't have trimtabs of any sort but vaugely remeber a trimwheel.
I could not immediately find anything about it in my books but your text explains it well, so thanks. http://forums.ubi.com/images/smilies/25.gif

F19_Ob
01-17-2006, 05:02 AM
I also remember some Gladiators having flaps wich were handpumped for takeoff and landing.
wonder if the J8 had that?

ElAurens
01-17-2006, 05:37 AM
Our model in the game does.

leitmotiv
01-21-2006, 04:37 PM
Today I received my answer from Alex Crawford (author of the Mushroom publication on the Gladiator) regarding lateral trim controls on the Gladiator: "As far as I know there were no lateral trim controls on the Gladiator. I've had a look through my files and can't find any references to them." Thus, it looks like the J8A should not have lateral trim capability.

F19_Orheim
01-22-2006, 05:15 PM
I'll check my resource material which we used for the J8A project. I am not sure it did have lateral trim, but I would say "no". So this is perhaps a "fault" in the game. But then again, there are loads of "faults" in-game so this minor detail is no biggy.

For example, the J8A was known to be able to fly inverted almost as good as "upright".. .. not the case in sim right? The engine stutters and shuts down. But I wouldn't bother with these details, just fly it and enjoy...

PS.. If you are interested here is a small excerpt from an original J8A manual from 1938 which I translated for Oleg back when we were in the middle of the project. Maybe it could be fun for you guys if you are as nerdy as I amhttp://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

http://f19vs.se/files/J8%20description%20eng%20translation.pdf

leitmotiv
01-22-2006, 05:54 PM
Thanks for the manual, F19_Orheim! I am going to build a Roden J8A as one of F19's aircraft in the Winter War---you wouldn't happen to know which aircraft Lojtnant Per-Johan Erik Salwen flew? I am looking for all the information I can find on F19 and the Winter War J8As. Any help would be deeply appreciated. As for the lateral trim business---well, I can just not use it---problem solved! I recognize in any undertaking as huge as these sims errors will happen. I love the J8A and the sim J8A. I also love the Poli I-153s and I-16s---whenever I "fly" them I prefer a Veteran J8A as an opponent---much to my distress!

F19_Orheim
01-22-2006, 06:58 PM
No problem mate... The Roden model is actually quite nice, I have one of my own which have been waiting for a year or two to be built.

Here are some nice pages about the RodenJ8A/Gladiator model and a few tips and tricks:

http://www.ipmsstockholm.org/magazine/2005/10/stuff_eng_olsson_gladiator.htm

http://kits.kitreview.com/gladiatormkiireviewbg_1.htm


https://wx6.registeredsite.com/user842300/Reviews/Archi...den_48_Gladiator.htm (https://wx6.registeredsite.com/user842300/Reviews/Archive/Kits/Aircraft/Roden_48_Gladiator/Roden_48_Gladiator.htm)

Some nice tips to improve your final model:

http://www.ipmsstockholm.org/helpdesk.asp

About what ID Salwén used. Well the pilots in the "real" F19 (12 fightherpilots from the start) didn't really have their own planes. They took turns. Consider that they were 12 pilots and 12 J8A from the beginning, but the extraordinary conditions during the Winter -39/40 with -25 C and below took a toll on the aircrafts and it was not always that they worked.

Now I know that Salwén used the "F" (or ID number 284 printed in small black number on the side) when taking a I-15bis down the 17th of January 1940, but this plane was also flown by Ian Jacobi when he shot down a I-15 the 12th of January 1940. Of all the J8A ( ID A-L) the "F" as in "Fredrik" was recorded with most kills. This particular plane crashed beyond repair on the 5th of February 1941 back in service in Swedish Air Force at F10 (Flygflottilj 10), Bulltofta, Sweden.

The one standing at Malmen Airforce Museum (and which is the best ORIGINAL restored Gladiator in the world and used as the main reference in the game) is the "H" or "278", last flown in service by F16.

You can see a few nice pics of the "H" in section "HANGAR" on our webpage. Unfortunately you won't see the pic of me grinning in the cockpit of it as I took reference pics for Capt_Haddock (aka F19_Haddock)... but I promise.. my grin was WIDE. Actually the cockpit is very roomy. I am 6'3 (191 cm) and quite big and I felt a bit small in it. Many think that the Gladiator is small, but I tell you, it's quite big".
When you see the cockpit images you will understand what an amazing job Haddock made with the cockpit in-game.. it is a perfect copy!!!

If you want a correct cammo for the "F" you can use this skin which is one of the 12 I have made for my fellow F19 members. IN the zipfile you also get the original marking of the "F" when it flew originally by F8 (Flygflottilj 8) Barkaby, Sweden.


http://www.f19vs.se/files/J8%20F19_F_F8-54.zip

leitmotiv
01-22-2006, 07:50 PM
Magnitude 1 thanks, F19_Orheim! I will make Fredrik 284 (which, I noticed, was included in the Roden kit---why is it without national insignia---was this after the 13 March end of hostilities?). I will use your skin as my guide, and the fantastic cockpit phots on your website. F19_Haddock did do a great job on the cockpit---my favorite Maddox "office"---I will use it for details and weathering. I will also cheerfully use Fredrik's skin in my QMB brawls in hope that it will continue to be a scourge to Polis! I am a 6'4" half-Swede who was bent over nearly double in a B-17G's 1st pilot's seat when I had the opportunity to try it for size. I am glad the Swedish government showed good judgment in selecting an aircraft suitable for all!

F19_Orheim
01-23-2006, 12:22 AM
hehe, well I never did consider the brits be to bulky, but they sure did make a roomy ariplane http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

The Roden kit I think is cased together with no-national markings. The Swedish J8a's were marked with the Finnish von Rosen crosses during Winterwar 39-40. After the conflict was over and the J8a's were flown back to Sweden the pilots overpainted these blue crosses with no-nationality markings, such as "a devil", "a skull", "a gunner" etc. I am not sure whether the kit is shipped also with the von Rosen crosses, I see that there is a skull on the frontlid but as I said, these were only for the flight back home to Sweden and the J8a never flew combatmissions with these markings. I really don't understand Roden's reasons for shipping it with these markings but I gather they just thought they looked cool.


There is only one book written about the F19 Squadron called "F19 - en kr¶nika" (F19 - a chronicle) by Greger Falk who was a lieutenant during the war and Signal Officer at F19's HQ in Rovaniemi, Northern Finland. It was published by the Swedish Aviation History Association many years ago. It is written both in Swedish and Finnish but unfortunately not in English (not sure if you speak the lingo even though you are 1/2 Swedish). It's a great book with loads of photos from the operations during Winter War. Hard to come by though.

leitmotiv
01-23-2006, 04:20 AM
You will never believe this, F19_Orheim---I found a copy of "F19-en kronika" in Anaheim, California, and I bought it online instantly! Although both my mother's parents were Swedish, she never learned the language, and I speak only English and very bad German. You have been a great source of information, and I and my Roden J8A thank you heartily! I am going to keep my eyes on the F19 Squadron website. Cheers!

F19_Orheim
01-23-2006, 05:26 AM
My pleasure mate. Fantastic tht you found the book.

Here is the remembrance plaque of F19 outside F21 (Flygflottilj 21) who are "tradition carrier" of the volunteerunit F19. F21 lies in Lule¥ up north.

http://www.f21.mil.se/images/local/f19sten.jpg
http://www.f21.mil.se/images/local/f19platta.jpg
It says "F19. The Swedish Volunteer Squadron defended northern Finland in the air during the Winterwar"

Maybe not so much information but the Finns and Swedes up north are known to be quite taciturn: http://forums.ubi.com/images/smilies/10.gif

ElAurens
01-23-2006, 08:00 AM
Thanks for posting the J8A performance specs.

I hosted a DF last night that only had the J8A, Cr42 and PZL P11c, and was wondering about the J8A's real world numbers. It seems awfully slow compared to the numbers you posted. (Pity the poor P11c, it is even worse...)

It is great fun though, and really emphasizes energy retention and situational awareness.

Hopefully we will get the Avia soon, another fine cr@p plane!

F19_Orheim
01-23-2006, 09:04 AM
Well it is a tad slow. I suspect that Maddox has mistaken the J8A for a J8, the same difference between these as between a MKII and a MKI

leitmotiv
01-23-2006, 10:31 AM
Thanks for the images of the remembrance plaque. I had no idea the Swedish government sent military aid to Finland until recently, and I thought nothing could surprise me about the war. My uncles, although American Swedes from Colorado, kept up the taciturn tradition!

mortoma
01-23-2006, 11:51 AM
I don't think it's a big deal that it has elevator trim capability in the sim. For the simple reason that if there are people who want to fly it realistically, they can simply ignore and not use the trim, flying like an I-16 instead. Just because something's there does not mean it has to be used!! Just pretend the ability is not there and don't touch Ctrl + up or down keys. Problem solved..................

F19_Orheim
01-25-2006, 10:33 AM
you're so cleverhttp://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

leitmotiv
01-26-2006, 02:29 PM
F19_Orheim: received Greger Falk's F19 today from Anaheim, California---yehaaaaaa! Guess you can get anything in Los Angeles after all!

x6BL_Brando
01-26-2006, 03:21 PM
Er, Leitmotiv, I still haven't met up with the ex-RAF pilot I mentioned in a similar thread (whose father was a pilot also, got his wings in 1926 etc.)

I'm pretty sure that he will confirm what you posted a while back - that the deflection of the elevator was controlled by a wheel-operated worm screw. I'm hoping to find out whether the play was taken up by a shaft or cable. I expect the latter though I'n not sure.

It certainly seems as if the entire movable surfaces were moved. As you state, there are no trim tabs, but tabs are not the only method used. Literally, trimming implies the adjustment of one or more axes to achieve stable flight. This can quite simply involve keeping pressure on the stick and pedals, as LW jockeys will attest. Assisted trim is a refinement, enabling the pilot to relax his hold and even fly hands-off for a period. In some cases this was done by fitting a pre-bent 'tab', angled to aid in overcoming the innate 'set' of the aircraft in question. (I won't go into what causes these imbalances - Tully & others have described that very well elsewhere.)

Further along, a major advance was to make these tabs adjustable, either mechanically or with electrical or hydraulic assistance. However, I think the Gladiator will prove to be an example of an intermediate development. The ability to set an angle of deflection to a whole surface and lock it in place! The worm-wheel is very well suited to this purpose.

I expect the procedure involved manually putting in the required deflection for a given angle (e.g. climb) and winding the mechanism to take up the slack. I expect they relied on friction to keep it in place. The worm-wheel has a strong coefficient of friction used this way. But I guess the disadvantages are easy to see too - vibration is unfortunately a good way of neutralising the 'friction lock' - and the bigger the deflected surface the more vibration is generated.

The motorised trim-tab won out of course - but they had competition for a while. http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

B.

P.S. Will post when I've had the chat with the horse's mouth! http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

F19_Orheim
01-26-2006, 06:05 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by leitmotiv:
F19_Orheim: received Greger Falk's F19 today from Anaheim, California---yehaaaaaa! Guess you can get anything in Los Angeles after all! </div></BLOCKQUOTE>

Great man, that is awesome. This is a rare book, hard to come by even in Sweden. I have heard rumours about a reprint but the local Airplane Book Shop said the other day that's just a rummout .

Too bad it's in Swedish/Finnish (Swedish on the left side of the pages, Finnish on the right. The Finn's words are looooooong )

Hopefully you can still enjoy looking at the pics and maybe get a date with a Swedish girl who can translate for you http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif Winter 39-40 is known to be the coldest winter during the 20th century. One can only imagine how horrible it must have been for the pilots up in Northern Finland. The Swedes had at least closed cockpits with their J8A's (not in the Harts though), but the Soviet in their open Chaikas? woooo cold!!

leitmotiv
01-26-2006, 06:47 PM
I think I will get a Swedish grammar since Swedish girls are too smart to come to the wretched part of the empire in which I reside (Stockton, California). The Sov Poli pilots must have looked like flying bears with all the wool they must have worn---probably imposed a vision penalty! By the way, I am a battle-hardened bombardier: while in high school a friend of mine and I bombed two high schools---with toilet paper. I was staring right down at the earth, door of Cessna wide open, while lobbing rolls of paper---lucky the seat belts were high quality!

F19_Orheim
01-27-2006, 01:51 AM
hehe sounds like you have some swedish manners stillhttp://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

leitmotiv
01-27-2006, 02:05 AM
Traditions must be maintained!

Immermann
01-27-2006, 03:04 AM
I'm not taciturn.

Immermann
01-27-2006, 03:09 AM
I'm from Lule¥ by the way. But my dad's from Link¶ping. So I've spent some time in that museum when I was youngerhttp://forums.ubi.com/groupee_common/emoticons/icon_smile.gif My grandmother lived in Malmsl¤tt, just a few minutes from there. Can still remember sitting in the cockpit of that J29 they had (have?) standing outside. Can you still do that? I haven't been there in some years. Hmm, maybe this summer? I'm heading that way anyhow. I'm rambling... Hey, maybe I'm not taciturn?http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

leitmotiv
01-27-2006, 04:37 AM
I was talkative when young and at 53 am taciturn, but I am from the U.S. branch, and am likely ruined from watching "Leave It To Beaver" as a boy.

Stafroty
01-27-2006, 06:54 AM
if you want to fly historically accurate Swedish plane without trimm tabs, just dont use em them .) or is it so hard to control your needs for doing it?

F19_Orheim
01-27-2006, 09:18 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Immermann:
I'm from Lule¥ by the way. But my dad's from Link¶ping. So I've spent some time in that museum when I was youngerhttp://forums.ubi.com/groupee_common/emoticons/icon_smile.gif My grandmother lived in Malmsl¤tt, just a few minutes from there. Can still remember sitting in the cockpit of that J29 they had (have?) standing outside. Can you still do that? I haven't been there in some years. Hmm, maybe this summer? I'm heading that way anyhow. I'm rambling... Hey, maybe I'm not taciturn?http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif </div></BLOCKQUOTE>

Yeah, it's still there, a tad worn due to weather and all http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif I know that they have big plans at Malmen about expanding the museum, they are planning to build a new Hangar where the wreck of the famous DC that was shot down bu russian migs back in 1952.

Also this summer a new multimediaexhibition about F19 will be opened, I think the opening day is 6th of June (national day).

http://www.flygvapenmuseum.se/program/index.htm

Capt_Haddock
01-27-2006, 01:22 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by F19_Orheim:
Also this summer a new multimediaexhibition about F19 will be opened, I think the opening day is 6th of June (national day).
</div></BLOCKQUOTE>

Multimedia? Nice. They could get a copy of FB to show people the J8A in action http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

http://www.haddock.f2s.com/sig/F19bannerh3.jpg

Immermann
01-28-2006, 03:03 AM
Hahaha, I just checked the museum page http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

Caption for the top picture (as written on the backside of the photography):
"Hamilton lands as ususal."

Now thats humour! http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

Immermann
01-28-2006, 03:07 AM
Now that exhibition sounds interresting, I gotta check when we're heading down there (it's my aunts 50th birthday).

F19_Orheim
01-28-2006, 06:03 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Immermann:
Hahaha, I just checked the museum page http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

Caption for the top picture (as written on the backside of the photography):
"Hamilton lands as ususal."

Now thats humour! http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif </div></BLOCKQUOTE>


Hehe, missed that text, yes very amusing. I know someone who says that about someone http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif@ someone (F19)