Linden Hill Posted November 16, 2011 Share Posted November 16, 2011 There should be no more than 5 bis operational, and one UM, if I am correctly informed. Hi Pollie, You are correct! I misspoke. I should have written 'half-dozen' above. Will edit. Quote Link to post Share on other sites
bjc2278304 Posted November 16, 2011 Share Posted November 16, 2011 Hi Pollie, You are correct! I misspoke. I should have written 'half-dozen' above. Will edit. What is the status of "114" from the markings sheet, you said it looks different now? storage, active? Quote Link to post Share on other sites
Linden Hill Posted November 16, 2011 Share Posted November 16, 2011 114 is still operational but heavily weathered. A certain other ARC poster has the photos! Quote Link to post Share on other sites
bjc2278304 Posted November 16, 2011 Share Posted November 16, 2011 114 is still operational but heavily weathered. A certain other ARC poster has the photos! Very interesting, thank you. Brett, Quote Link to post Share on other sites
Libor H Posted November 16, 2011 Share Posted November 16, 2011 Libor, are the decals Cartograf printed, as in the MF Profipack? Stencils are made by us. The main decal sheet is made by Cartograf. Quote Link to post Share on other sites
ya-gabor Posted November 16, 2011 Share Posted November 16, 2011 (edited) The question on the differences between the MiG-21 MF (Type 96) and MiG-21 bis (Type 75A and 75AP) has been raised several time. The internal differences dont affect us that much but the external or what is visible from the inside is more important. The MiG-21 bis fuselage was redesigned in several ways to accomodate new equipment, engine and new production technology. Many of this internal changes are well visible on the airframes. Please find attached a drawing showing the main external differences, please note that this is only the fuselage, there are some changes on the wings too. A mid production MiG-21 bis was taken as the basis for the comparison with the MF (also from the main production batch). What is not shown on the drawing is the: - new nosecone ring which is completely different both in size and detail, - the cockpit differences, - the new R-25 engine, looking up the tail will give a completely different picture from the previous engine types, - main undercarriage bay internal details, - new ejection seat for some late production batch (8th and 9th) examples, like the ones in the Finnish AF service, - new windscreen quarterlights, once again on late batch 8 and 9 aircraft, - not marked on the drawings are the different types of AOA sensors, - there were three different types of alcohol bottle covers on top of the nose. Apart from the apparent new nose section and the new saddle fuel tank inherited from late production SMT examples, the bis had: - new, bigger panels on the sides of the fuselage behind the cockpit, - the small airvent under the canopy seal is repositioned: turned 90 degrees unticlockwise, - cover for the forward radio compartment had different details and service panels, - new cover for the after radio compartment with a bulge on the right side and two large screw heads on top, - the GS-23L gun feed system was changed and the bottom door for the links repositioned, - the fuel filler cover was smaller and of a new design, - the airintake for the fuel system (after the refill opening) and the vent on the left side was slightly changed and repositioned (together with the refill opening) due to the different internal structure of the new fuel tank, - still on top, the panel after the fuel tank had a long bulge on the right side to cover new equipment, - the size of the next panels towards the back of the aircraft were also changed apart from the bigger shape extending further back, - new gun blast shield, - new, shorter GS-23L gun cover with the smaller spent shell ejectors, - new forward airbrakes, - new panels in front of the airbrake for system ground test connections, - new panel after the main airbrake for engine system servicing, - new panels on the rear underside, - the cut out on the tail section was bigger and reiforced from the inside, - the small airintakes on top of the rear fuselage were of a different shape, - new wing fences with three sections introduced, - details added to the inboard wing pylons, - and of course the PION antenna for the RSBN system was introduced under the nose and on top of the tail for the Type 75AP versions. There are some othere changes, in this case small to mention or not readily visible. There are also the local changes introduced with different antennas, new cockpits and lots more, but they are not tipical for the main batch of MiG-21 bis which was the subject of this search. Hope this can be of help in your work on the MiG-21 bis kit, which ever you decide to build, the Academy, the Fujimi or the OEZ version. Best regards Gabor Edited November 16, 2011 by ya-gabor Quote Link to post Share on other sites
Laurent Posted November 16, 2011 Share Posted November 16, 2011 Thank you for the illustrated explanations Gabor. Quote Link to post Share on other sites
stenkabg Posted November 16, 2011 Share Posted November 16, 2011 A picture of the BVVS MiG-21 bis 114 taken by me in October 2010. More BVVS options and stencils would be more than welcome. Quote Link to post Share on other sites
pollie Posted November 16, 2011 Share Posted November 16, 2011 114 is still operational but heavily weathered. A certain other ARC poster has the photos! IIRC 114 was the last BVVS MiG-21bis to receive a major overhaul at the Georgi Benkovski maintenance facility at Graf Ignatievo. I took some photos when it was rolled out of the factory in September 2002, freshly painted. I'll check if I have those pics digital. Quote Link to post Share on other sites
Linden Hill Posted November 16, 2011 Share Posted November 16, 2011 A picture of the BVVS MiG-21 bis 114 taken by me in October 2010. More BVVS options and stencils would be more than welcome. Hi Stanislav: Yes, she still looked like that a couple of weeks ago, however the canopy has been replaced with one in the original camo scheme, so is now much darker green. We may combine the BVVS MiG-21bis decals with the MiG-29s, especially Bort 30 'Hogbuster'! Quote Link to post Share on other sites
bjc2278304 Posted November 17, 2011 Share Posted November 17, 2011 Great photo Stenkabg, I love that faded camo for some reason. I understand the Mig-21bis is long obsolete but it's sad seeing those BVVS machines are some of the last kind flying in eastern europe outside of Croatia and the modified mf's in Romanaia. Nearing the end of an era.... Brett, Quote Link to post Share on other sites
pollie Posted November 17, 2011 Share Posted November 17, 2011 Stencils are made by us. The main decal sheet is made by Cartograf. Thanks Libor, that is good news! Quote Link to post Share on other sites
pollie Posted November 17, 2011 Share Posted November 17, 2011 Great photo Stenkabg, I love that faded camo for some reason. I understand the Mig-21bis is long obsolete but it's sad seeing those BVVS machines are some of the last kind flying in eastern europe outside of Croatia and the modified mf's in Romanaia. Nearing the end of an era.... Serbia also still has a few of them flying. I wonder if any Fishbeds will be flying in Europe in 2015. Maybe a few Romanian examples..... Quote Link to post Share on other sites
stenkabg Posted November 17, 2011 Share Posted November 17, 2011 We may combine the BVVS MiG-21bis decals with the MiG-29s, especially Bort 30 'Hogbuster'! That would be great! The Bulgarian MiG-21 bis have some interesting camo schemes and it would be great is a separate deca sheet dedicated to the them is made. Great photo Stenkabg, I love that faded camo for some reason. I understand the Mig-21bis is long obsolete but it's sad seeing those BVVS machines are some of the last kind flying in eastern europe outside of Croatia and the modified mf's in Romanaia. Nearing the end of an era.... Though obsolete they gave some hard time to the Lakenheath Eagles during the millitary exercises in Bulgaria. Hopefully they will still fly some time. Quote Link to post Share on other sites
ya-gabor Posted November 17, 2011 Share Posted November 17, 2011 Little more on the MiG-21 bis compared with the MiG-21 MF. For comparison several visits were made to an aircraft storage base and museums for the research. In this case this was a non destructive way of measuring fuselage details. Here a margin of error could be expected, but several measurements were made and an average calculated to minimise the error. A far better way of measuring the details is when the fuselage is disassembled or cut into pieces. The later is a very sad site for any aircraft lover but it can yield excellent details, measurements and photos of thing which other ways would never be available, reachable or visible. For this, notes were used from visits to the aircraft scrap yard and aircraft overhaul facility where the aircraft were taken apart right down to the last panel. The saddle fuel tank: The two saddle tanks are completely different both in shape, size and construction. The easiest way to measure them was to take them of from the aircraft. They are fixed just at six location points and connected to the fuel system in several places. The MF fuel tank is a very slick affair, widest point on it is 630mm immediately at its front, from here it decreases to 475mm at its end. The MiG-21 bis fuel tank is a left over from the days of the SMT and it has a part number starting with 50 also reminding of its past. Late SMT’s and those retrofitted with a smaller tank had this particular model. It is still a big one. In fact it is two completely separate fuel tanks welded together. It is 690mm wide at the front, the widest point is 762mm and it is 1630 mm from the front. At this point the fuel tank is 480mm high. Here the side walls of the fuel tank are almost vertical at the very point where it meets the fuselage. The internal structure, the support ribs inside the tanks have a different spacing for the MF and the bis tank and so the fuel filler cup and the fuel system pressurisation system with its air intake on top and the system vent on the left side was moved back on the bis. The fit of the fuel tanks to the fuselage is far from perfect, in fact there is a gap of 8-16mm where it meets the fuselage surface, so don’t fill the gap here, only where there are panels. The edge of the fuel tank has a seal fitted to it from the inside. The front and end panel line of the fuel tank, going around its surface at a right angle to the direction of flight is in fact an overlap of the panels in front and behind the fuel tank. There is a level difference here and not simply an engraved panel line. About the nose section: Horizontal diameters were measured for both types. The perfectly circular cross section (MF 870mm, bis 905mm) of the air intake turns into an oval shape which by the time it reaches the forward cockpit pressure bulkhead is 1150mm horizontally and 1250 mm vertically. For a Zero reference point the intake lip edge of the MiG-21 bis was used, accordingly the lip of the MF was at -40 mm. Every 100 mm going backwards on the fuselage the diameter was measured. It was found that the diameter difference between the two nose sections was starting to show at around 500 mm from the nose. Here the diameter of the MF started to decrease constantly while that of the bis showed minimal change. On the MF the diameter decreased constantly to that of the final intake diameter. On the MiG-21 bis the diameter starts an abrupt decrease (see the photos published few days ago) around the 300 mm mark and ending up at the intake diameter. The difference between the nose sections diameters is measured in few centimetres but what is important is the completely different shape/form of the intake section. While you would never make out with a naked eye those few differing centimetres in diameter, the new curvature of the bis intake is very visible. This is what have been ignored up to now by kit manufacturers! Best regards Gabor Quote Link to post Share on other sites
ya-gabor Posted November 17, 2011 Share Posted November 17, 2011 For comparison of the MF and MiG-21 bis nose section here are two views from almost the same view point. For clarity a MiG-21 bis of the earlier version the Type 75A was chosen. Here the nose did not have the PION antenna of the RSBN system. The MiG-21 bis is board number 4025, while the MF is aircraft 8204. Also a view of the last flight line with just a “few†of the MiG-21 MF, bis, UM, MiG-23MF’s and Su-22 which were withdrawn from service. The aircraft were all collected on the by then storage base of Papa. Best regards Gabor Quote Link to post Share on other sites
Jennings Posted November 17, 2011 Share Posted November 17, 2011 So is there really any difference between MiG-21MFs and MiG-21bis's? Quote Link to post Share on other sites
AV O Posted November 17, 2011 Share Posted November 17, 2011 Even though you could read it or understand, these interesting pictures are trying to sort it out : http://www.master194.com/forum/viewtopic.php?f=54&t=60844 Quote Link to post Share on other sites
Dmanton300 Posted November 18, 2011 Share Posted November 18, 2011 Gabor, Thanks for that, it is THIS kind of research I love to read about, and it feeds my desire for specifics (and the long dormant precision aviation machinist in me!). Brilliant stuff, and really shows how different the Bis nose is. It's a far more brutal looking affair isn't it? Quote Link to post Share on other sites
ya-gabor Posted November 18, 2011 Share Posted November 18, 2011 Hi Jennings, The difference between the nose sections diameters is measured in few centimetres but what is important is the completely different shape/form of the intake section. While you would never make out with a naked eye those few differing centimetres in diameter, the new curvature of the bis intake is very visible. The question of a new fuselage for the MiG-21 bis is not only concentrated on the new nose section, although this is also very important, but as noted a few posts above there are lots of other surface detail differences for the bis. The Eduard MiG-21 MF kit is excellent but not perfect and it had many mistakes on it, combined with the new surface details of the bis, Eduard had here a chance to correct the mistakes from the MF kit and add the bis details to produce an almost perfect bis fuselage (never before made by any kit manufacturer (we had some not so bad bis saddle fuel tank before). Lets hope for a MIRACLE in December from Eduard in that MiG-21 bis box. It has been done before in December! :) Or will we have a surprise from China??? Best regards Gabor Quote Link to post Share on other sites
ya-gabor Posted November 18, 2011 Share Posted November 18, 2011 There are several ways to measure a real aircraft. :D :) :D This is one of the options (not for me). Best regards Gabor Quote Link to post Share on other sites
toadwbg Posted November 18, 2011 Share Posted November 18, 2011 There are several ways to measure a real aircraft. :D :) :D This is one of the options (not for me). Best regards Gabor LOL! Is that bird poop weathering on the tail? Quote Link to post Share on other sites
ya-gabor Posted November 18, 2011 Share Posted November 18, 2011 (edited) Hi toadwbg, Yes it is. Birds simply love to sit there and leave a "mark". Now how about reproducing that in 48 or 144 scale? :) Of course this MiG has been standing there for close to ten years, so there was time to have a lot of material collect on the fin. Still this one is in good shape as compared to some of the others where almost all the paint is missing. Best regards Gabor Edited November 18, 2011 by ya-gabor Quote Link to post Share on other sites
Jennings Posted November 18, 2011 Share Posted November 18, 2011 (edited) There are several ways to measure a real aircraft. ] That's the TrumpetBoss method! Edited November 18, 2011 by Jennings Quote Link to post Share on other sites
Jennings Posted November 19, 2011 Share Posted November 19, 2011 Interesting. I'm still curious about the new fuselage halves... Quote Link to post Share on other sites
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