Sovietwarplanes

What were the external differences between Tu-2 and Tu-2S?
Also, was the four-blade prop introduced during GPW or was it a post-war modification?

S stands for 'standartni' meaning standard.
I believe much of those differences are actually internal.
the four-blade prop was introduced late in the war so there weren't that many in combat.
if you are wondering about the ICM kit it does depict the Tu-2S with ASh-82FN engines.
if you want to build an early version you can sand off those bulges on the cowling sides for the ASh-82A version.
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Where could I find some photos of wartime machines with four-blade props?

OOPS! it seemed I goofed.
looking through what little I have on the Tu-2 it seemed the four-blade prop
(AV-9VF-21F) wasn't introduced until 1949.
sorry! my bad? :-[
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Damn, it would look really cool on a GPW machine... with that three-tone NKAP bomber cammo... where could I find some painting info on three-tone Tu-2 (it kinda rhymes? ;D)

well, the basic patterns can be seen here :

http://vvs.hobbyvista.com/Camouflage/NKAP_Template2.php

as I understand it you can do AMT-1/4/7/12 or AMT-7/A-21M/A-24M/A-32M
then comes the next question: how do you determine what plane used what scheme and what colors?
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You forgot that GPW series had shorter carburator intake on top of the cowling (didn't have air filter) and a bit different main canopy glazing ( on the side the fuselage-window line is straight not broken). Tu-2 and Tu-2S i belive also have some differences regarding some of the panels and early Tu-2 used early in the war (since september 1942 on Kalinin front 132. OBAP and 12. BAP part of 3rd air army - machines produced in Zavod No.166 in Omsk) had divebrakes.

Drawings for details and different series can be found here (i know this isn't really nice to support pirates but i can't find the paper copies anywhere)
Voyna v vozduhe No.66 Tu-2 chast 1(War in the air No.66 Tu-2 part 1):
http://www.wunderwaffe.narod.ru/Magazine/AirWar/66/Draw/index.htm

Voyna v vozduhe No.67 Tu-2 chast 2 (War in the air No.67 Tu-2 part 2):
http://www.wunderwaffe.narod.ru/Magazine/AirWar/67/Draw/index.htm

Regarding camo:
In Aviakollekcija magazines 01 and 02 2008 (Modelist-Konstruktor). On colour profiles early machines produced in Zavod No.166 are given as standard 2 tone green-black and some Tu-2S machines from 1944 are drawn in two tone gray fighter camo (colour profile of plane with marking Moskva 32 from 6. BAP in summer 1944 is given as such). On page 79 of volume 2 there is also a skech of 3 tone upper camo used by Zavod No.23 in 1944 that produced most of the machines with colours used:
green ( A-24M )
dark grey ( A-32M )
Brown ( A-21M )

is there any way of linking these factories to particular production batches?  From what I can see (which is not a lot) some of the visible changes - single large or three small semi-ventral windows, twin small or single large mgs (and associated canopy changes?), smooth (and larger?) cowlings as opposed to ones with small blisters - can be tied to production batches.  OK, I've absolutely no doubt that they were so tied, but what is known?

The HobbyBoss kit is much the same build standard as the ICM one which is a later standard, but comes with the earlier green/black camouflage.  This seems possibly unlikely.

Graham, I wouldn't go too much by Hobby Boss' painting guide.  This kit is probably of the later type machine, when they resumed production (Tu-2S), so would have the three-colour paint scheme.  From what Massimo has posted on his page on the Tu-2, it appears that there wasn't much standardisation on the three-colour scheme.

Regards,

Jason

I suspected that was true about the green/black camouflage, although I don't know whether I can rule it out on the early main production batches. It would help if batch numbers could be linked to dates, at least   There is conflicting information in different sources, notably the introduction of the small engine blisters - Block 20 or Block 49 - and the three semi-ventral windows, which is of course the standard of both kits.  I'm comparing the drawings given above with the block descriptions in Putnam's Tupolev (Gunston).  The plans only have the blisters on aircraft with single large semi-ventral windows.  Gunston has the combination on Blocks 44-48. but a photo of blistered cowlings and single large window captioned as block 20-44.  Gordon's Soviet Air Power isn't a lot of help.

One query is about the canopies: the one in the ICM kit is flatter (and with one right side window slightly bulged, something I've found no reference to).  However this flatter shape doesn't seem to appear in the drawings above.  According to Gunston this is a Block 48 onwards feature. It isn't visible on the plans above.

PS  The 4-bladed props are linked to block 59, together with larger fins and rudders (sensible enough to an ex-aerodynamicist), and a larger nose transparency from Block 48.  So just adding 4-bladed props to the kits is certainly not possible, but do these block numbers really mean postwar - 1949 as one source says?  If block 48 is postwar, then the blistered cowlings could be too - shock horror gasp.  Then again, just what is the difference in external diameter of these cowlings?

Since we discussed recently Soviet aircraft designation system, including "Types", "Series" etc, what is the "Block"?

We?  As an irregular visitor to this board, I have not been involved in any such discussion.  I presume that you are expressing a desire for the use of the term "series" for what in my main source is termed "Block".  Is there some genuine possibility of confusion in this matter?  Does the term "Tu-2 series 60" actually refer to something other than the term "Tu-2 Block 60" thus providing a genuine source of misunderstanding?

If there is no such possibility of misunderstanding, and you are merely trying to insist on some conformity of expression rather than being helpful, or perhaps in advance of being helpful, then you could have expressed yourself more tactfully.

If conformity of expression is insisted upon on this board, perhaps it could be made clear in the header?

 I feel the need to expand on this subject.  I was using the terminology in Putnam's Tupolev Aircraft since 1922 by Bill Gunston, which as far as I can tell is still the best work on the subject in English.  Bill Gunston was a highly respected technical writer of many years experience, with a particular interest in Russian subjects.  This is entirely understandable in the Cold War years, of course.  He chose to translate the Russian word here translated as "series" as "block".  The man did not have a tin ear for language, so he must have had good reason for this.

I believe that this is because "series" is not used in this way in English.  Though the term is close, it is what is described as a "false friend", a word that looks as though it means the same thing but actually means something else.  This is something to be aware of when translating from French to English, for there are many words that appear to be the same but meanings have drifted.  The French "demander" only means "to ask" - "demand" has a much stronger meaning in English.  The same is true in other languages.  Doolittle told of a speech he made on a South American sales tour, where "looking down on the great flatlands of your country" went down very well in one country but brought laughter in another, where the word for "flatlands" meant "bedpans".  I suspect the same basic problem exists between the Slavic languages.

As I understand it, in Russian use the word "series" describes a short production run of identical aircraft, that is aircraft built to the same technical standard.  A new series may simply mean more of the same, or a change is introduced.  Relevant to the Tu-2 would be a new canopy, new ventral gunner windows, a new gun mount, or new engine cowling.  This is directly paralleled by the American "Block Number", but the British do not recognise any such grouping.  The dynamics of mass production are universal, aircraft being built in short runs of identical standard in all three countries, but in Britain this is just referred to by the generic term "production batch".  The British did use the term "series", but only to a very limited extent with a distinctly different meaning.  To my knowledge, this was only used for the Hurricane Mk.IIA, the Mosquito Mk.IV, the Tempest Mk.V, and the Halifax Mk.I, II and V.  For the first three, it was used to separate a short initial production run that was known to be in advance of the intended standard, and although the "term series i" and "series ii" were used the latter fell immediately from use and the normal system of production changes continued without any change in the designation.  The Halifax Mk.1 is perhaps closest to the Russian use, with short production runs of series i, ii and iii.  The Halifax Mk.II however is completely different.  A run of the series 1 was followed by a long run, incorporating many changes, of the Mk.I(Special), and then a similarly long run of the Series 1a.  A planned series 2 did not go into production.  The Halifax Mk.V was just a variant of the Mk.II, and copied the series as appropriate.

Further, we can speak in English of "a series of production batches", something that would be very little sense as "a series of series".  I suspect these are the reasons why Bill Gunston chose the familiar American term "block" to translate the Russian "series".  On reflection, I'd have used "batch", as apparently the closest in English English.

We actually discussed VVS aircraft nicknames and official designations and it was tough.  I assumed that you were familiar with the discussion about Soviet "Series" that us other forum members had in Dec 2012 (not so long time ago).  Check it at:  

http://sovietwarplanes.com/board/index.php?topic=1482.0

I have tried there to explain meaning of the Russian word "seriya".  I also used English word "batch" to describe it. I hope you will get the idea what were Soviet "Series"...

Regarding Tu-2 :); in 1942 and early 1943, Omsk Factory No 166 made 80 planes in 7 series.  First two series had 5 planes each. 3rd, 4th and 5th series had 10 planes each. 6th and 7th series had 20 planes each.  20 planes in a series was a standard number of bomber planes for Soviet factories.

Production was then discontinued in Omsk and in late 1943 reinstated in Moscow Factory No 23.  Factory No 23 started with "1st Series"!  I don't have precise numbers for each series, but there must have been 20 planes in each series - Tu-2s of the 35th series were completed in June 1945.  After the war Zavod No 23 increased number of planes in each series to 50.

49th Series which introduced taller canopy was definitively a postwar series.

HTH,
KL      
 

Thank you.  I still feel that the terminology is a translation difficulty, and do not accept that using "series" rather than "block" or "batch" is necessarily any improvement, but let's move on to the aircraft side.

At first sight the size of each Series appears low, considering that over 3000 examples were built discounting the later Irkutsk builds.  By this listing, no more than 780 had been built by June 1945.  Gunston (Tupolev aircraft) states that the main production was on two lines, GAZ 166 and 156 (starting slightly later).  Allowing a second parallel line would give us 1480 if both lines reached the same output/Series number at the same date.  With another three years of production following on it at 50 per Series, it does however seem a more respectable number for wartime build. 

In a more modern source, Gordon (Soviet Air Power) offers rather different and lower numbers, quoting a total of 1,013 aircraft by the end of the war (which end?) for a total of 2,527, but speaks only of the main production at Plant 23.  This suggests higher Series sizes than 20 if only Series 35 had been reached in June.  However, Gordon also talks of production of "little more than" 30 per day in 1944: this is clearly an error.  30 a week would exceed the full wartime production in less than one year.  30 a month appears too low for a single source, but about right for two.  A peak of 3 per day would seem to be the best match for a single source, but 2 appears more likely.

I would assume that the build standard for both factories (if two were involved) would be largely in step, so that the Series number would still be a close (but imperfect) way of noting the modification standard.  After all, the requirements for change would be the same for both factories.  It would not however help if one line adopted a distinctive feature due to changes in supply - for example if the aircraft with three windows for the ventral gunner was from one factory whereas the aircraft with one large window was from the other.  I'm not suggesting this was the case.

I feel that it was the lower canopy which was the later one, as it appears on aircraft with other features of later production such as the 4-blade propellors and the semi-open gun positions.  The Monino aircraft rather than the Krakow one.

In model terms, this makes the HobbyBoss kit a Series 20 (or later) variant, suggesting a delivery in Autumn 1944, unless we accept that the triple window layout is indeed from Series 44, making all such aircraft postwar.  I feel this is an error, but would appreciate better information.  The ICM kit is Series 49, lacking the revised aft canopy of series 50.

I am not insisting on anything - if "block" is more appropriate for Russian "seriya" (note that it is singular), we should start using "block" for LaGG-3, Pe-2 or SB Series too.


My mistake - Zavod No 23 must have increased Series size from 20 to 50 in late 1944 or early 1945.  Gunston was also wrong, there was no parallel production in two factories during the war.  Main wartime production was in Moscow Factory 23.  Production from 1942 to 1945 was as follows:

Zavod 166 Omsk
1942 - 79 planes
1943 - 1 plane

Zavod 23 Moscow
1943 - 16 planes
1944 - 378 planes
1945 - 742 planes

After the war in 1946 - 1949, production was reinstated in Omsk with about 200 planes produced.  For Omsk, those postwar Tu-2s were series 8 to Series 18...

Zavod 39 in Irkutsk made further 200 or so planes between 1947 and 1950.  Balance to 2500 was made in postwar years by Zavod 23 in Moscow.  

 

With these figures I think you were right at first, but it may depend upon where "postwar" is set to start.  If Zavod 23 Series 35 appeared in June 1945, this is consistent with 20 aircraft per series up until then. This assumes no major change in production rate in 1945.

I now have a clearer picture of most of the features affecting the external appearance, but am still uncertain about the wartime (or not) existence of the triple windows for the ventral gunner.  This would affect judgement on the colour scheme appropriate to these aircraft, I suspect.

Or indeed whether my ICM kit is correct in having a slightly bulged starboard side window on the late canopy, or whether this is a moulding flaw - it does seem to fit the window size rather too well to be mould damage.

I've just browsed through Kotelnikov & Saukke's Tu-2 Aviakollektsiya issue (probably the best published reference) and it looks that triple windows for the ventral gunner are OK for wartime planes.  Profiles representing Omsk Series 1 and Series 3 have one small window, Omsk Series 6 has triple windows.  Triple windows remained standard at least till 1946.  One larger side window for the ventral gunner was among improvements proposed at the end of 1945.  Some of these improvements were included in 44th Series produced in early 1946 (according to the profile one large window was included in 44th Series).  Other improvements like bulged rear part of the cockpit canopy were introduced in early 1947 with Series 50.


Larger fins and rudders were introduced with the beginning of production in Moscow (i.e. with the beginning of production of the Tu-2S), nothing to do with 4-bladed props...  Tu-2s made in Omsk (a.k.a. Tu-2VS) had smaller fins and rudders.

4-bladed props were introduced from the 21st plane of the 59th series in Moscow and from the 17th plane of the 5th postwar Series in Omsk, probably in late 1947.

Hope this helps,
KL 

Yes, indeed, thank you.  I had wondered whether the reference to the triple windows appearing in Series 44 should really have been the reverse.

I'm a little surprised to see changes such as the 4-bladed propellers) being introduced in the middle of a Series.  I'd assumed that all the aircraft in a series would be to the same build standard.  This suggests that the Series number may not have been as useful for supply purposes as I'd assumed.

The reference (Gunston) to a change in tail size was to the 59th Series and apart from any change early in the aircraft's life.  The 4-bladed propellers would have been slightly destabilising so a larger fin would not be surprising here.  I've seen no photos showing any such change, but later examples seem to be less well recorded, and any small difference may not be obvious.  The Tu-10 does look to have had a slightly larger fin (and is so described), but this could have been predicted for the longer (inline) engines.  For the Tu-2S directional stability is said to have been comparatively poor (Gordon), so change in this area would be expected.  Is it possible that the increase in tail area followed the initial trials rather than always having been part of the revised design?

It therefore seems that the Hobby Boss kit, though somewhat basic, only needs a different camouflage scheme; whereas the superior ICM kit requires a change to the ventral gunner's windows.

In theory that should not have happened. In reality, it happened quite often, especially with various equipment modifications.


According to 1943 NII VVS tests directional stability of Tu-2 was worse than directional stability of A-20 or Yer-2, but better than Pe-2.  In February 1944 one Omsk Tu-2 (No 100716, i.e. 16th machine otf the 7th Series) was modified with enlarged fins and rudders, it was tested in March and modification was recommended for the series.

Series as batches of identical planes were introduced to deal with delays in production caused by the modifications.  Series were never seen as designations for new modifications; they were never seen as useful for supply purposes.  VVS never referred to modifications by Series.  On the other hand, Series were used in manuals to designate modifications (manuals were usually made by design bureaus attached to the main production facility) and that is why modern historians and modellers use Series to describe modifications.

HTH,
KL

 

It is therefore a logical implication that early Series from Zavod 23 in Moscow will have had the lower, rounder, top to the fin.  This presents another option for modelling: it will be interesting to look at photos to try to identify these aircraft.  It would be interesting to know the series in which they were introduced, clearly long before the 59th.  Differences in the rudders does not appear obvious - at least I can't see them.  It is possible that earlier aircraft were upgraded.

For supply purposes, it is necessary to know which parts are required by which aircraft.  If this is how the manuals handle the matter, I'd have expected the supply system to do the same.  To make a crude simplification, if the Southern front has no aircraft before Series 20, there would be no point in local stocks of parts superseded by Series 15.

Correct, early Tu-2S made by Factory No23 had smaller tail fins.  It is not clear when larger fins were exactly introduced.  Tu-2S (16th plane of 7th Series, made in june 1944) tested by NII VSS in Oct 1944 had larger fins installed.