When i was asking if it was re-branded what i actually ment was that were these systems bought under a Russian spec from other western or japanese composite producers… but having looked at the specs i have my answers.

Matt, I do not know whether this supports or hinders your thoughts on the background of early soviet composites, but the FAA article you posted (I almost forgot that it exists, I`ve it for several years) analyzing composite structures on the Mig-29 was also based on data obtained from prototype Mig-29 b/n 04 flight tests which was flown for the first time in may 1979. The aircraft is now rotting at Khodynka airfield and photos I made some years ago there prove that early air inlets were made from composites indeed. Also note some tensometers mounted in the composite tail structure. May I remind you again that the baseline Mig-29 doesnt have composite leading edge, composite air-inlets nor composite engine fairings. They were removed in early 80ies from the production and replaced by metal parts causing minor weight penalties.
The Mig-29 has been designed with the methodology called there “усталостная прочность или безопасной срок службы” meaning in the west equivalent the “safe-life” practice with components which should withstand loads and not fail(safe-crack life) within defined 20years and 2500 flight hours. Well, the extensive use of composites in Mig-29 structure were VIAM and Tsagi recommendations, but later failed bcs some bonding technologies were not matured yet.
As it is known criterias for design evolved in the west from “safe-life” to “damage tolerance” in 70ies, what is a philosophy assuming that cracks already exist and will grow(permits cracks and defects in the structure) and then determining whether they will cause failures. I suppose this was the design approach adopted for the whole USAF fighter familly of the teen series the F-15,F-16, F-18 with their highly “overshoot” values of service life e.g. 6000-8000 flight hours. If I`m right Russians adopted this approaches later in nineties.

Read the paper if you want to know about repair of composites.

Ehm, the russian documentation of the izd 9.12 describes composite repairs in more detailed manner after all. 😉

regards
M

hmm whole new world of data.. interesting..

You are quick,I wanted to post a similar VIAM link.
http://www.viam.ru/index.php?section=135&language=2

Who copied from who?, Sorry, never been much interested to find answer on that question. From what I know the Mig-29 prototypes built in late 70ies had a lot more composite structures than later serial produced aircrafts in 80ies, bcs some of the composite bonding technologies were not matured yet and causing fatal accidents during first flight tests. For example, the whole intake with engine cowlings were composite structures early one, changed later to metal material in serial production. As I mentioned already , there are few KMU-4L, KMU-4E and KMU-3 CFRP except those other fiber glass materials.

to find more about them , use search engine http://www.rambler.ru. I hope you can read Russian.;)

regards
Martinez

Also from experience at college i know not all aluminium alloys used in Aero are easy to weld.

That`s correct, there are difficulties with Al alloys structures as well, e.g. when moulded, machined, welded,.. especially when they are in the precipitation-hardened state what is by the way the prime state you use them in the a/c structures. Most known and well used is the 2024 alloy which when welded is loosing mechanical properties bcs of changing inner structure causing residual strain around the welding zone. You might restore strenght properties in the HAZ by heat-treatment again, but when heating a complex machined part you could run into further problems. Opposite to the 2024 Al alloy there are many which possess good welding characteristics e.g. as I remember we recently overhauled external 1520l fuel tanks for the Mig-29 fleet. The whole fuel tank is one single welded Al structure with some fuel aggregates, tubes and signal probes inside and if you want to run defectoscopy and repair those things, you had to cut openings wherever it was needed, make repair and then close it by welding a patch over there….then those EFT`s look very patchy:)

As for the 787 composite structure I think new repair methods are still being developed and investigated as new composite materials and who knows maybe in the future the so called self-healing composites will answer all the questioning about their a bit demanding repair characteristics.

Rather interesting fabrication; more details what is it for…?

The “ONPP Technologia” plant is doing everything from space to railway composite material sub-components. Why do you think when a group of Russian women is cooking something on the table manually has to be from the upcoming high-tech PAK-FA???? :D:D Just to reminder what technologies are used to manufacture high strenght composite materials.
http://en.wikipedia.org/wiki/Composite_material

copy & paste from russian web

have you seen this? 😀

P.S. I`sorry, it`s been posted some time ago

Hello Ted,

Welcome and thanks for clearing a few things up. It is a pity that Mr.Davies book has not been written with that level of details you showed in those few sentences here. I`m really enjoying reading you. English is a great language, wish all people on this planet have learnt it in the past, we would have been discussing things much easier. I regret that I can not bring my older colleagues (Flogger pilots) over here as they do not read and write a word in English. You asking why? Well, we learnt only one foreign language for the most part of our lives, guess which one.. :)Some of the Flogger pilots I know retired in nineties with roughly several hundred flight hours more in the cockpit than you, some continued and retrained for another type like the Su-25 or ended careers in the military flight school on the L-39 jet trainers. Please do not be angry with me when I doubted “Red Eagles” experience with the Flogger recently, but that`s what I thought about Mr. Davies book and his endless bitching and giving readers a wrong impression of what you remember when you`ve been flying it. Well, if that is your experience, no one can change that….In general I feel nothing but admiration for Red Eagles, all military pilots, no matter what side they have flown for, bcs once when I was a little boy ( I`m not alone here) I have dreamed to be one as well. Nevermind, I`m working for years in the aircraft MRO service once overhauling the Migs-23BN/UB, currently me being assigned to the type Mig-29.

Would the engine be damaged if the aircraft entered a spin? Yes, in the MS. The engine was braced quite well for + or – G, but not for lateral G so when it spun, the engine would hit the side of the case and compressor/turbine blades would snap. We had first hand experience with this. The BN engine was braced better for lateral G and was not damaged during a spin (I have personal first hand knowledge of this one).

That`s an unique experience pointing to a serious engine design fault. I wonder whether the designer/test pilots would have confirmed this finding that engines installed in the Mig-23M, MS, MF were about to be destroyed in an aircraft spin. Do you remember what facts led you to believe the R29-300 engine was not braced to engine casing sufficiently when experiencing lateral Gs or by any chance is there a possibility that you might be mistaken in that conclusion?
From engine design standpoint, beginning with engine to fuselage attachments, engine casing and suspension system, type of bearings, rotor and stator assembly of the eleven stage twin-spool compressor and turbine section, front and rear engine supporting struts,…….. the engine R29-300 used with the Mig-23M, MS, MF is almost identical to the R29B-300 used with the BN. The difference between them, the R29B-300 is having a slighty smaller combustion chamber and shortened nozzle optimalized (no laval type, supersonic converging/diverging nozzle) for subsonic regimes and low altitudes only. All what it meant was less thrust but a bit better SFC value. There were also changes to the engine fuel-regulation system, but by any means the R29B-300 can`t be seen as an improved version of the R29-300, but rather, a modification to suit subsonic operations of the Mig-23BN.
I`m not trying to underestimate the situation during the spin, but would like to point out the importance of another reason that may explain the damage of the R29-300 engine in your case. When entering a spin the R29-300 engine (most of) is going to stall very hard as a result of disrupted air flow to the air intakes and engine power settings. You may remember hearing an extremely loud pulsating noise and bangs like swiping metal on metal.
This was not the sign of engine hitting the side of the case or compressor/turbine blades snaping each other, but the sound of inlet duct panels and auxialiary louvers deforming caused by high vibrations and pressure unbalance inside the intake/engine section. Flogger pilots whether unintentionally or intentionally entering spin with arising compressor surge were instructed to immediately shut down the engine to reduce risk of burning/destroying turbine blades caused by engine overheating (red warning light). The turbine outlet temp gauge “TOT” gauge ITG-1(placed next to Fuel meter) might get crazy within several seconds bcs the turbine blade cooling was insufficient, not to mention fuel still flowing, even worse if burning. The point I want to make here is that the compressor surge was a very common phenomenon for pilots with the Mig-23/R29-300 and we lost a plane that way as well, overheating engine not able to restart, at low altitude, but pilot ejected safely. I remember to read in the past aviation history that a compressor surge might be able to completely destroy an engine (blades snaping each other due to violent vibrations), but we doubt the R29-300 was that case, not to mention the engine being damaged by an aircraft spin movements…..for sure most unlikely.

The problem with the Mig-23 suddenly departing from controlled flight and entering spin at high AOA with less warning has been known from the begining. When flown at high AOA and not carefully watching your yaw rate the Mig-23 could enter spin at considerably lower AOA compared to initially evaluated 35-36 degrees. This issue has been addressed in east block Air forces during late seventies on all previously delivered Floggers (except the Mi-23BN) by installing a cross-coupling system between the rudder and lateral control channel of the Mig-23. The DPR-23 (btw. Mig-29 is using the same) probe “Datchik Polozhenja Ruchky” was attached to the control column sensing its lateral movements. According to airspeed, altitude, lateral stick movements and the actual AOA the SAU-23 autopilot was adjusting the rudder to counteract unwanted yaw motions when turning on high AOA ensuring better directional stability. You know the system probably under another name, e.g. ARI – Aileron Rudder Interconnect. I wonder if anyone of Red Eagles has test flown F-14 Tomcat, aircraft badly known to be prone to spin and compressor surge. Why wasn`t this system installed on the Mig-23BN? It is obvious, because the BN hasn’t been designed for the high AOA air-to-air missions even if the “duckbill” shaped nose was making the situation even worse. Meaning the asymmetrical flow pertubations around aircraft forebody creating yawing moments. By the way, there are numerous memoirs written by former Mig test pilots or better say “spin doctors” like S.A. Mikoyan, A.V. Fedotov, V.A. Orlov, A.A. Scherbakov or V.E. Menitskyj evaluating the Flogger for the most part of their lives confirming your findings about spin characteristics of the Mig-23.

If I understood it correctly, some of you have flown both the Mig-21 and the Mig-23 together. The chapter describing Red Eagles experience with Mig-23 landing characteristics was the most terrifying one. Actually, true is that during the landing with the Flogger, pilot should have paid more attention to both the airspeed and AOA in relation to landing weight before touching the runway, bcs when a little surplus of speed or improper AOA was set you bounced back into the air or ending up on the runway jumping like a crazy goat.:) All it required was a bit more practicing with the Flogger high-lift landing configuration. No one was complaining, but hell are you saying the landing with the Mig-21 was ever better at 170-180knots? Not sure you were flying the Fishbed version with the blowing flap system. Anyway, have you ever noticed that Flogger main landing gear was extended a bit asymmetrically causing negligible yawing effect you`re complaning about when landing? Thanks

Best regards
Martinez

No visit to Chernoye?

I`m not going there, bcs a lot of AN-2 planes and Mil helicopters. Ken has already been there.
http://www.flankers-site.co.uk/mos2008_day06.html