martinezCan you provide a reference that shows ‘western pilots’ describing this ‘cobra’ as a ‘legitimate combat maneuver’?
just for a start, USAF Col John Boyd, one of famous combat pilots ever.
copy&paste
Boyd was famous for a maneuver he called “flat-plating the bird.” He would be in the defensive position with a challenger tight on his tail, both pulling heavy Gs, when he would suddenly pull the stick full aft, brace his elbows on either side of the cockpit, so the stick would not move laterally, and stomp the rudder. It was as if a manhole cover were sailing through the air and then suddenly flipped 90 degrees. The underside of the fuselage, wings, and horizontal stabilizer became a speed brake that slowed the Hun from 400 knots to 150 knots in seconds. The pursuing pilot was thrown forward and now Boyd was on his tail radioing “Guns. Guns. Guns.
http://www.aviation-history.com/airmen/boyd.htm
martinezWhile L-band IFF is not revolutionary (so why make a big deal about it in a trade show display?), why would you add the weight and complexity by putting 3 or 4 foot long IFF antennas in the wing leading edges and not in a nice small conformal antenna? Why force the need to install not one conformal, but rather two very directional IFF’s in each wing LE and likely one additional for the rear? Sorry, but explain to me how installing IFF transceivers that large makes any sense at all. You don’t add needless weight to an agile combat aircraft so you can have the world largest combat aircraft IFF set. Unless you are insinuating the IFF will be L-band and located elsewhere and the wing LE arrays will be Ka band…
What are the chances, judging from the size of antenna elements, TR modules inside the aircraft leading edge and proclaimed utilization for so called target identification or “IFF” as well, that the russian L-band active array to be millimetre-wave active array radar system in the frequency band 40-60Ghz (military JSC-ECM band), instead of conventional IEEE frequency bands where L-band denotes 1-2GHz?
copy&paste
http://knol.google.com/k/vijainder-k-thakur/tikhomirov-niip-aesa-radar/yo54fmdhy2mq/34#
In 2003 NIIP Tikhomirov general director, Yuriy Belyy, revealed the conceptual architecture of the radar in an interview with Interfax-AVN.
He explained that “the forward and side coverage radar sets (LOKATOR), the millimeter (wave) radar set and rear view radar set and the electronic countermeasures complex (KREhP). At the same time, KREhP signals are passed through an active phased array antenna array (AFAR).”
“The side coverage radar will not be located on the fuselage, but in a fairing beneath the fuselage. The Tikhomirov NIIP is supposed to coordinate the fighter’s whole avionics complex (in frequency and timing patterns and the like),” said Yu. Belyy.
I admit not being a radar expert, but what are current and future capabilities, benefits and applications of military active scanend array millimetre-wave radars?
Can they be used for active millimeter-wave guidance,high angular tracking accuracy, for covert operation-LPI, reduced ECM vulnerability and at last the target identification (non-cooperative NCTI) or the IFF?
martinezRe: D30FM6, how long can the higher temperature be safely employed?
Do not know how it is done on D30FM6, but I pressume it could be similar to the RD-33. The RPT regime is switched ON automatically after:
1. engine throttle at full AB
2. total pressure inside the engine intake higher >0,7kp/cm2
3. speed equal or above Mach1,5
RPT is limited to 5minutes during the flight, the T4 temperature (TIT-Turbine Inlet Temperature) rises 25 degree C more. Also on the Mig-29 there is a switch hidden in left landing gear bay ground presonal has to switch ON before flight. Usually no thrust values are given(in the manuals) when RPT is engaged, bcs it is not a static thrust measured on a stand.
martinezNot sure what i said to get such reply…:confused:
I was unsure what you meant. Reason; Future Su-34’s will be in dark gray, that is what rumors say anyway. Like new Mi-28N’s, Mi-8’s and Mi-26’s. So, i was wondering if you talked about that paint. And that grey paint, is for RCS.
I`m sorry, but what did you expect after bringing your sarcasm into play? Not sure what you wanted to explain anyway, your answer doesnt have sense at all in regards what we have been discussing here.
martinezmartinez, sorry if i am being stupid, but what grey paint do you mean on Su-34? That on the nose cone and other dielectric panels?
Berkut, please do not be angry with me, you know what we are talking about, then why playing stupid? Is the nose cone and dielectric panels only grey on the Su-34? If yes, then don`t tell me it is an aluminium color you can get by adding a PAP-2 powder to a clearcoat……:D
martinezIs there any easy visual indications between the MiG-21M, MiG-21MF and MiG-21bis?
Did all MiG-21MF have RP-22, or some/all have RP-21MA radar?
Peter, for sure no MiG-21M/MF was ever fitted with the RP-22, but with the RP-21M/MA radars. The RP-22 with the R-3R missile was cleared for export versions of the MiG-21Bis only. To distinguish between the MiG-21Bis and the MF no hard task at all, but between the MF and M it is different. Many MiG-21M went through overhaul during its service life and were re-equipped with some extra things you mentioned before and then renamed to MiG-21MF. I was taught the basic difference is the R-13-300 engine installed on the MiG-21MF only, the MiG-21M having older R-11F2SK-300 and then I found out that Polish airforce is having a MiG-21MF with R-11F2SK-300 with added gun deflector plates and/or periscope…..:eek::eek: So there is a mess and unless you have not got the logbook at hand you could be still wrong…:D
there are better forums to speak about Mig-21 differences than this, try http://www.airforce.ru
martinezEngines MiG-31M: D-30F6M, full reburning of 2*15500 kg (ПФ – полный форсаж), a mode of the raised draught of 2*16330 kg (РПТ – режим повышенной тяги?)
Нет, на русском языку это значит Режим Повышенной Температуры. На РД-33 тоже используется этот режим.
martinezAs Su-34 considered ‘new’ weapon system I don’t want to dig deeper at the moment.
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Ah, Geez, do not worry about that, you`re not gonna reveal the most kept secret of the Su-34 at all.:) You are not asking about weapon systems, avionics, ECM, radar frequencies, armament … etc. It is just a damn paint on engine nacelles looking suspicious at least to say compared to the aircraft camouflage, bcs they`ve applied it as a kind of last minute solution(maintenance forced I think) before being operational in RuAF. Just send over a question whether it is a CARC or not, if it is something else they simply wont comment on that.;)
Anyway, as we discussed the Su-34 nacelles I noticed after seeing several photos that there is some design alteration among Su-34 prototypes. The early Su-34 had some heat resistant parts built in, the last Su-34 No. 48 and further on had them changed to Al alloys completely .
I think the Mig-29KUB RAM paint is comming from Akzo Nobel, well established company on the russian military aviation market, also certified by VIAM. But do not think the Su-34 uses foreign RAM paint at all.
You know, Su-27 is quite old aircraft being in possession of USAF at ‘undisclosed location’ for many years already – but still some topics in 2 volume book didn’t pass censor’s eye.
I know that from Mr. Bedretdinov personally, bcs I was persuading him half and hour to handover me his second book at MAKS2009. I failed, but several months after MAKS I finally received it. I didn`t know what could have been classified and didn`t pass censor`s eye, maybe topics where Oleg Samoylovich was calling names at M. Simonov, stealing from him his project T-10….:D:D:D
martinezNot sure about that – the only aspects where I’d give the nod to the MiG-29 over the Su-27 is getting it right without a redesign and yes, definitely structural materials (where Sukhoi was extremely conservative). In most respects (aerodynamics, avionics, controls) the Su-27 is the more advanced design, but structurally ….
It depends how you look at it, the Su-27 is the bigger dog with a lot of space inside the fuselage including more fuel and avionics,….etc, Thus also having a different task in the airforce, giving him some kind of edge over the smaller point defence fighter Mig-29. Therefore I would not say the Su-27 has been more advanced design, rather equal in terms of avionics compared to Mig-29 Fulcrum C in the RuAF. Aerodynamics and flight controls wise I agree the FBW is the difference maker here, unloading stabs during turns so to speak increasing total lift. After reading the book Su-27 Rozhdenie legendy from I. Bedretdinov, describing how M. Simonov utilized design solutions already introduced on Mig-29, I have had my impressions confirmed. Anyway, there was a saying among ground personal taking care of Sukhoi aircrafts:“samoljot suchoy, technik mokroy”…:D hopefully no need to translate, just will add it was used before the Flanker time.
Well, even a honeycomb sandwich structure can be partially or completely non-metallic (I think the rudders and ailerons on the MiG are composite skins bonded to an aluminium core?). But yes, I am pretty sure they’re CFRP:
You right, I forgot about that, those have to be composite honeycomb structures (in russian written “Octorozhno Soty” as well) on engine nacelles and tails as well. If you check the picture of Mig-29KUB below you will see also written “caution honeycomb” on the fairing in front of the APU exhaust. I`m sure this is a standard Al alloy skin + Al alloy honeycomb which we have on our baseline Mig-29(horiz. stabs, flaps, elevons, rudders, vertic. stab. parts, between engine nacelles fairings). During depot level of maintenance you have to remove these parts and send them to NDT shop for water detection tests. Hopefully using CFRP honeycomb you are no bound to do that at all…who knows better about CFRP honeycomb maintenance, please correct me.
martinezThank you for the pics Martinez. Nice to see RAM paint confirmation, now it brings up some questions, what is the extent of the RAM paint and material application on the MiG-29K…and does anyone have information about the actual application of RAM on compressor face of engines in either 29K or 35BM?
I do not have any official statement, nor have read anything about it, so you have to take me with a grain of salt right now. I took some very detailed pictures and it seems that they`ve applied the RAM paint(it is under the grey topcoat) on the Mig-29 RCS hot-spots, meaning not the whole fuselage, wings and tails. I have seen a label saying “Caution special coating” on the front fuselage, engine intakes, on landing gear bays,….for sure on other places I haven`t noticed, but about the RAM on compressor face I do not know. Check some other pics below.
martinezMatinez, Ken –
I’m confused, but “Amīcus Plato, sed magis amīca veritas”. Of course, I can invent a theory that paint was weathered fast due to hight T as well, but it would be unfair.
Whatever, that mystery seems to be solved and confirmed by several industry sources.
Thanks:), but it simply explains why dont they paint high temperature resistant metals near hot exhaust, like stainless steel or Ti alloys. Its bcs Cr-Ni or Ti oxides formed on the substrate surface are non-porous, thus very bad for paint adhesion. You could paint them anyway, but paint will peel easily during the flight. In order to better the adhesion, you have to abrade the surface, but why do that?
Usually before painting the aircraft some preparation has to be done in the paint shop, e.g. covering surfaces you wont damage by paint, check for some pics from the paintshop here http://forum.keypublishing.co.uk/showthread.php?p=1680179#post1680179
But I was hoping you asked guys at Sukhoi what kind of grey paint do they use for serie produced Su-34, whether it is some kind of Chemical Agent Resistant Coating (CARC) or something else like a RAM paint. Hopefully, they wont be touchy to answer that simple question 😉
Regarding the T-50 engine nacelles as colleague Trident already pointed out it is quite interesting to see this part uncovered as on the Su-27 familly, literally naked to bounce the radar signal back. I think that this has to be an interim solution as well in order to lower the RCS signature. What do you think?
martinezTo solve a discussion, I’ve asked some questions to Sukhoi guys. Hope they will shed light on unpainted areas mystery.
If you remember, initial question was ‘why some areas on Su-27 family engine nacelles left unpainted’ and my answer was because they are hot and suggested that on final T-50 they will be covered with hight T RAM.
It was not a question ‘if Su-34 nacelles painted with temperature-resisting RAM.’ as I remember.
If I was wrong, I will admit it.
Ok, fair enough and looking forward to hear something about the mysterious grey paint on the Su-34 engine nacelles.;) Sorry for being dense before, but I have many grey hairs bcs once solving temperature resistance problems with the Mig-29 paint when regularly flying test flights MAX. MACH 2.35. I`m not sure but I would rather expect RAM paint on Su-34 front fuselage than on engine nacelles, what do you think? Just compare detail pictures of Indian Mig-29K front fuselage(below) with some SU-34 serie produced examples.
In general, painting heat resistant metal parts near engine, APU exhaust is not wise at all bcs of adhesion problems. Paint will peel easily from the surface.
martinezWell, that still leaves the question of what MiG did differently on the MiG-29 🙂 Similar engine cycle (BPR, TIT), similar installation – yet they were able to use a painted nacelle and the MiG-29K now even has composite skin in that area (despite a somewhat hotter engine).
This will be the irony of the fate, bcs Mig always fielded smarter and better solutions on its aircrafts than Sukhoi, even now as we know that Mr. Simonov literally copied many, many things from the Mig-29 prototypes when working on his T-10S. Probably the Mig-29 could have better engine compartment colling than the Sukhoi-27. I found a diagram showing the R-33 pressurization and blowing/cooling. Could someone post a similar diagram showing the Al-31 inside the Su-27 engine nacelle?
Btw. correct me if I`m wrong but doesnt have the Mig-29K engine nacelle a honeycomb structure? The CFRP composite skin was used on Mig-29 prototypes, later changed to metal sheet alluminium skin bcs the bonding technologies for composite skin were not matured yet.
martinezI always thought that unpainted areas at engine nacelles are made from titanium alloys (VT-20 and then OT4-1 for Su-27 family, VT23m for T-50). Seems that technical manuals are lying;)
Calculations of the airframe and systems temperature were performed by engineers Gladyshev and Tochilina (she was in charge of the fuel system temperature calculations). As a result “The Index of the temperatures of Object T-10” authored by Vladimir Gladyshev was released as a working document in the early stages of designing the Su-27.
Calculations showed that the maximum speed of flight, corresponding to M = 2.35, at an altitude of more than 11 km, airframe skin heats up to 140 – 150 ° C, the temperature of glass windshield reaches 143 ° C, intake duct walls are heated to 175 ° C. In this case, the engine is heated up to 550 ° C in the afterburner area, while in the area of the nozzle feathers – up to 1100 ° C. That required usage of the titanium alloys in the construction of the engine compartment, the installation of heat protection screens on the walls of the tank #4 and the ventilation system to prevent possible explosions in the engine bay in the event of leakage of hydraulic fluid and fuel.
Ahh, Flateric, Flateric, did you at least notice that the Su-34 might have the engine nacelle skin structure different compared to the Su-27? Check these collages I made for you and look for any engine nacelle differences on the top and bottom. What does the yellow color (btw. denoting strontium chromate primer for Al alloys) tells you? Are those Su-34 engine nacelles identical compared to the Su-27/35? I wasn`t arguing that there should not be any heat resistant parts of the engine nacelle at all, even the Mig-29 has some.:D:D
Also, quoting from Su-27 technical manual doesn`t help much when talking the Su-34.
Again, quoting from a book, especially from a chapter talking about the Su-27 only shows you`re not understanding the matter well.
1. Was the Su-34 max. speed calculated M = 2.35? ( in real it is hardly M1.8)
2. Then is the Su-34 airframe at max. speed heated up to 140-150°C? (for calculating basic aerodynamic heating formula you can use http://www.grc.nasa.gov/WWW/k-12/airplane/atmosi.html)
3. Then are intake duct walls heated to 175 °C at Su-34 max. speed? (high temperature mostly due to variable inlets, slowing the supersonic stream down to subsonic with a system of shock waves, how temperature differs with a Su-34 fixed inlets?
4. The engine is heated up to 550°C in the afterburner area. I agree, it applies to the Su-34 as well, there should be a heat resistant part covering the afterburner section of the engine nacelle, but where the hell are they talking temperature value between the nacelle and engine itself?
5. while in the area of the nozzle feathers up to 1100 °C , I agree, but I was not discussing this temperature.
I still stand by exactly what I said before. This grey paint on the Su-34 engine nacelle is just chemical resisting topcoat, not a temperature resisting RAM. Please prove me wrong. Anyway, I should congatulate you for solving the question Mr. FlankerMan was asking before. Why does the AL-31 on the Su-34 run cooler…:D:D
martinezI’ve been wondering about those unpainted nacelles for years….
My question is – how come they can paint over the same nacelles on the Su-34???
Does the AL-31 on the Su-34 run cooler ???
They are camo’d on top….
On the engine nacelles you have several drainage pipes exhausting engine oil and fuel. So on the engine nacelle surface you get all sorts of very agressive fluids(hydraulic as well) and to fight with paint deterioration you have to use some kind of chemical resistant paint like epoxide or polyurethane. From my experience with the Mig-29 maintenance(see pic below), the engine nacelles are painted with epoxy EP-150, whereas the rest of the fuselage (camouflage) is with the well known AS-1115, an alkyd-acrilic based paint prone to deteriorate when in touch with agressive fluids.
Think simple, the engine nacelles of the Su-34 are made from alluminium alloys or a honeycomb structure painted with a different kind of paint when compared to the rest of the fuselage surface. It is a just a grey chemical resistant topcoat.
The engine bay(space between nacelle and engine) is well vented and cooled by a by-pass flow taken somewhere infront. There should be temperatures no more than 80deg C, therefore saying that engine nacelles are damn hot and need a temperature resisting RAM is simply a BS.
One detail picture of the Su-34 engine nacelles and you see how poor they were painted.
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