AndraxxusYep, lower drag index (4 vs 5) but greater weight (341 vs 195 lbs) Edit: on wingtip pylons they both have drag index of 4 =)
AndraxxusGood stuff – all seems fairly logical. How did you fudge the effectiveness of the fuselage onto the wing lifting area; did you go with a planform area and then factor by 0.9?
I didn’t, because lift effect from the fusalage is typically added to the “wing area”. F-35A doesn’t actually have 42,7 sqm wings. If you calculate from schematics, it has 5,2m root chord, 1,5m tip chord, and 3,7m span for each wing; [(5,2+1,5)/2*3,7]*2 makes 24,79 sqm. Same goes for F-22, Su-27 or F-15 also.
One outstanding high-level assumption though; the F-16 leave the airfield with 6 AAMs and the F-35 leaves with 4.
True, that assumption was more about weight calculation than the actual capability; F-35 may carry 6 internal AAMs in the future who knows..
F35 carry sidewinder internally??? If not, some pylons should be added also no?
At current state no; but like Flexible stated AIM-9X have LOAL capability so can be launched from the internal bays. Same goes for IRIS-T or ASRAAM. I think its more of an integration question. If customer wants it, it will be integrated.
AndraxxusYou are right, traditionally first of those graphs would be for clean 50% fuelled aircraft, so I never bothered to check it; A rather idiotic mistake on my part. Its roughly for clean 25% fuelled F-16 (I am using PW-229 graph by the way). F-16 on 50% fuel should weight around 24000lbs. Turn rate conversion graph says we could subtract 2 degrees per second. Or better, the excel file i did is interactive. I will post for 13300 kg + 8390 * 0,25% = 15398kg F-35;
Clean F-16 and Clean F-35 both on 25% fuel:
[ATTACH=CONFIG]226026[/ATTACH]
F-35 still has inferior maneuverability at S/L in terms of ITR and STR, but the gap is clearly narrower. at 30k feet, it has some advantage at subsonic speeds. Same statement also applies to SEP graph. I have double checked, and i did used 24000 lbs acceleration data for F-16, so that graph is correct.
This is new data actually looks more “right” to me; I was suprised by the huge performance drop due to 6 pylons and 4 missiles (I had checked the weight for that graph; F-16 would weight around 25500 lbs, so I directly used 26000 lb graph) Now the performance drop seems more logical.
AndraxxusHave you validated any testpoints from any official data reg the F35?
Apart from that question… Amazing job.
I can give it a try? What are the most current published official data?
AndraxxusThe real question is why anyone would be satisfied with performance comparable to an aircraft fielded 40+ years earlier, particularly when that aircraft’s performance has been eclipsed by, err, just about everything fielded since.
Well the F-16 may be 40 years old, and with each variant its maneuverability degraded, but its still not that bad; Even blk50 variant is still the most maneuverable (maybe excluding F-22) fighter in USAF inventory. Italian pilots say F-16 can match Eurofighter below 10k feet, and on excercises F-16 did managed to get some gun kills on Rafales. Grippen is said to have 20 deg/s STR, so its superior to that also. F-35 was never meant to be highly maneuverable. That decision is certainly foolish and narrow sighted, I agree on that part.
Thank you for the hard work Andraxxus, a very interesting read (although the mathematical part is way beyond me of course).
Would you some day be willing/have the time do something like that but vs. the likes of J-20, T-50, J-31 etc.? Or even F-22 vs. those? 🙂
PS: Oh yes, Rii is perfectly right, so how about vs. Rafale or Typhoon or even Gripen? That would be extremely interesting!
I am planning to do for F-22 someday, to see how it compares to legacy fighters because its also published to use 6 series airfoil. While some part of designation is classified; I can play with different airfoils to get some results.
As for other aircraft you mention, they would be very difficult because I have no info about their wings to run an estimate. I might use some TsAGI airfoils and data from Su-27SK manual for T-50, but for J-20 J-31??? I don’t know where to start. (I had no info about F-35 also, but both its predecessors F-15/16 and its generation counterpart F-22 uses NACA 6-series, I’ve made an assumption it will follow the same fasion)
Rafale Typhoon and Grippen are deltas, they use much less draggy wings with little lift coefficients i have no info about them too. Maybe I could use Russian estimates about M2000 as basis, but that would be way too inaccurate to defend the results.
Amazing job Andraxxus, any chance at all you could do it for the JF-17 in comparison to the F-16? I would totally want to publish that!
Unfortunately same problem would arise for JF-17, I don’t even know if they use NACA airfoils, TsAGI airfoils, or Japaneese or they have their own airfoil system.
AndraxxusWhat difference source? af.mil factsheet? So kilogram as a weight unit change from manufacturer to manufacturer? 1 kg for LM is actually 3 kg for Boeing, right..
Here, some good readings for you, because you are starting to sound utterly stupid, no offense.
http://en.wikipedia.org/wiki/Kilogram
http://en.wikipedia.org/wiki/International_System_of_Units
By the way, even the numbers you give does not support your claim (22+12+12 = 46 != 45).
AndraxxusI understand the numbers at the end refer to thickness of the foil ?
So 64A203 is only 3 % thick where as 64A204 is 4% and 64A215 is 15% thick..entirely different wing with entirely different flight caracteristic and drag etc. I think there is a reason why can’t find them…they are classified.
Correct about thickness. However as wing design concerned all 3 airfoils are;
-6 series = optimized for laminar airflow;
-4 indicates minimum pressure area occurs at 40% of the chord (or was it maximum? feel free to check it), which should define a) how and where flow seperation (stall) begins, and the location of the supersonic shock forming at transonic speeds.
-A hypen indicates they are extremely low drag from Cl=0 to design point.
-2 indicates they all have design point of Cl=0,2.
While last two digits tell about thickness, it doesn’t affect the wing behaviour all that much. Thicker wing will reach its design point at smaller AOA, but will have poor supersonic performance. Generally speaking, thicker wing will also have higher L/D ratios at low speeds, at the cost of higher drag at high AOA. Thicker wing gets (at subsonic speeds) more efficient as the reynolds number increase. Thicker wing will be less demanding on materials and can be lighter and easier to manufacture, but it can also be heavier due to increase in physical size.
I merely put 64A215 as an example, it was similar enough for the job. As for 64A203 and 64A204, do behave so similarly that without reading the title, you cant tell the difference from their respective data. None of the NACA airfoils are classified, they are present on airfoil catalogues. 64A204 for example is present on my fluid dynamics book from university. And there is no point, F-16 Blk50 supplemental manual is on the net. One can find any and all performance data he wants. If engineers want to classify; they either dont give the airfoil number, or they give it as 6xxx04.
AndraxxusIf Su-27 is 16.3 ton than Su-35 is about 15.5 ton. Su-35 has 34.5 MTOW. deduct 11.5 ton fuel and 8 ton weopon load. you get 15.5 ton. Su-35 has 3600km range with 4AAM. which is consistent with its weight and engine power.
So B-1B has 216 tons MTOW, can carry 23 tons external and 34 tons internal payload an has 120 tons fuel capacity; it is about 39 tons empty right???:very_drunk: LOL you are off by 47 tons :stupid: Margin of error 120% :eagerness: After explaining MTOW 3 times with a dozen examples, I will leave you with your flawed way of thinking.
http://www.af.mil/AboutUs/FactSheets/Display/tabid/224/Article/104500/b-1b-lancer.aspx
Edit: Just noticed something: According to your way of calculation, if you Fully load an F-15E, it will have same weight of empty B-1B. Excellent :highly_amused:
AndraxxusMiG-29KUB 967 had empty weight of 12200kg. Single seat MiG-29K might have slightly less weight, although due to extra 600L fuel tank it could be the same.
Possibly. It maybe lighter because of the removal of second pilot, but also heavier with because of the addition of fuel tank and necessary accessories. However as they will share a common platform, I don’t think they can remove weight from cockpit area without disturbing the CG, I would not expect more than +/- 200 kg difference.
http://www.youtube.com/watch?v=nuCvUTNLe0E this is MiG-29M prototype 156 (9-15) performing at Farnborough ’92. Notice 360 at 2:31-2:46. However, we have to take in consideration that it was flown by highly experienced test pilot Roman Taskayev. Recent displays almost certainly involve G limitations, since RAC MiG does not have abundance of airframes for both test flights and airshow displays.
Good display, but I don’t see your point. I never said MiG-29M is a flying brick, I said it wont be able to match or exceed all parameters of MiG-29A. Cobras, or 16 second 360 turns are not unseen from MiG-29A’s displays. Yet rolls are both quicker and more precise I will accept that. Also I don’t understand why saying its heavier or less maneuverable offends some people?
Andraxxusbaseline Su-27 is 1970s product built on 1960s machinery. it has nothing to do with MIG-29K
I also can give you example of Su-35.
And I would say there is no way Su-35 matching the 16.3 ton empty weight of Su-27S, too.
I am sure MIG-29 real weight is revealed to him only and real life logic of performances does not have any weight.
In fact he mentions MiG-29M has comperable climb acceleration etc performance to MiG-29A and have greater precision and better controllability at higher AOA. Agreed on comperable, I am debating “better or not”.
no need for that as its not reliable.
Reliability is subjective as we are speculating about an aircraft no one has fully reliable info, but as you wish.
its good you admit your mistake. so by your logic 13.3 ton heavy aircraft with massive cockpit & much more powerful engines than Rafale can fly 2000km only on 4.5tons internal fuel?
By my logic? Ok;
-Better aerodynamic optimization at cruise speed? Baseline MiG-29A has superior acceleration to F-15A or Su-27S at sea level, despite inferior T/W. At 345m/s at S/L, it also has higher max SEP than both, -again- despite inferior T/W. I think that should tell us how efficient MiG-29 is on straight line. IDK if Rafale is better or not in a straight line, but my mk1 eyeball inspection says I would put my money on MiG-29.
-Baseline “smokey” RD-33s on MiG-29A have 75kg/kN.h specific fuel consumption. Snecma M88 on Rafale has 79,44kg/kN.h, in other words original RD-33 is more fuel efficient than M88. Add to that, MiG-29’s variable inlets are both less restrictive than S ducts on rafele and have better pressure recovery (yes, even at M0,8). I think its safe to assume FADEC equipped smokeless RD-33MKs are even more efficient than RD-33?
Both factors combined, MiG-29 should require less thrust because its less draggy(debatable, theorizing), and generate that thrust more efficiently by consuming less fuel?. Its a reasonable assumption IMHO.
However your logic of comparing range with fuel is flawed; 4460 kg for 2000 km range on MiG-29M = 2,23 kg of fuel per km. MiG-29A has 3300 kg fuel for 1430 km range = 2,31 kg of fuel per km. By your logic, you declare MiG-29M to be lighter right?
Then compare F-14B and F-35A with same method. F-14B = 2000km with 7348 kg = 3,67 kg per km, F-35 = 2220km with 8320 kg = 3,73 kg/km. How does your logic explain the fact F-14B is more fuel efficient than F-35A despite being 6,5 tons heavier, having 1 ton less fuel, and having 56+kN more thrust compared to F-35A? It has a massive cockpit too. 😀
MIG-29OVT predates RD-33Mk certification .The point I am making is that such heavy thing like TVC did not have big impact on performance.
And my point is, you cannot judge the impact of adding 150 kg or 1500 kg by simply looking at the airshows; OVT can have 3 deg/s inferior STR perfomance on paper, and you wont even notice it. Watching blk30 and blk50 F-16s both in videos and in person, I have never noticed any performance difference. But there is; at sea level (where airshows are made) blk30 can match or beat any aircraft of its era in a sustained turn (and i would bet it can also beat the current ones, including F-22), but the blk50 stays largely inferior to the aircraft of its era. This is a huge difference, IMO. As an another example, can you say Su-34 airshows are bad? Or just by looking, you can say there is full 5 ton weight difference from standard Su-27?
MIG-29 is fundamentally very sound and future proof design. you have to admit certain designs have more upgrade flexibility than others. that’s why its on small carriers of Russian and India.
For you maybe. If you ask my opinion MiG-29 was always a “safe” design; While all ground breaking technologies are applied on Su-27, while it was completely redesigned for superior aerodynamics, or it’s advanced avionics delayed to get operational status, there was the MiG-29 which protected SU airspace.
MiG-29M should have been THE MiG-29 from the beginning. Relaxed stable, longer ranged, flexible, open for development. It -or MiG-35- come 20 years too late to be called future proof. That is my opinion though.
Andraxxus7.3ton of increase MTOW is for increase internal fuel and greater external load. It has nothing to do with empty weight of fighter. about 100kg reduction in engine weight. add to that 15% composite and titanium airframe with light weight avionics. the aircraft could be lighter than original one.
Nonsense. MTOW weight has nothing to do with internal fuel or external payload. Baseline Su-27S has 16300 kg empty weight, it can carry 9220 kg usable fuel and can carry 4430 kg of payload, totals out at 29950 kgs. Its MTOW is however dependent on landing gear bus type, 28000 or 33000kgs. Su-34 22300kg empty, 8000kg payload 11400kg fuel = 41700 kgs, yet have 45100 kg MTOW. Tu-160 = 110000 kg empty, 171000kg fuel capacity 40000 kg payload capacity = 321000kg yet MTOW = 275000kg.
I can name dozens of of other examples. MTOW is just as the name suggest, maximum weight an aircraft can take off from required runway distance. It may be limited by structural reasons (ie if you load too much weight it will break), or by aerodynamic reasons (it cannot generate enough lift at the end of the runway for take off).
MiG-35 may have lightweight avionics, but it has much more numerous avoincs and other equipment so thats not a valid comparison. Original 9.12 did not even have chaff/flare dispansers. MiG-35 has a potent AESA, MAWS, much improved RWR all will add to weight. More advanced materials in greater amounts yes, but MiG-35 has double the lifetime of 9.12. From your analogy, F-16 blk60 could be lighter than F-16A, because of advances in materials and avionics, but that does not hold true; Its full 2,5 tons heavier than the original. Again, MiG-29A weigh 10900 kgs, MiG-29M 13380 kgs. Suprise; its also 2,5 tons heavier. Somehow if you think some Russian magic will make MiG-35 full 2,5 tons lighter despite the bigger long life airframe and more avionics, you are mistaken.
where is that 4.5ton fuel figure come from.
From Yefim Gordon’s Midland series book “MiG-29”. page 115 To quote exact text:
The deletion of dorsal auxillary intakes made room for additional fuel in the LERXes increasing the internal fuel capacity to 5720 litres or 4460 kg of usable fuel.
I can post the screenshot if you like, I am using too much of my attachment limit.
and no way it can have so short range of 2000km with 3ETs. MIG-29M has 3200km range with 3ETs.
You are right I remembered it wrong. Checked it and its 2000 km on internal 3200 km with 3ETs, MiG-29K = 3000 km on ETs
heavier than this and that without any data to back up. MIG-29K is new unified platform from which all other MIGs are derived. it is not not just wings but much larger cockpit and nose.
I think that is what I’ve said already? All of the new built products (Current) MiG-29K 9.41, MiG-29KUB 9.47, new MiG-29M 9.67 (for Syria) and MiG-35 is a unified platform. Merged from Project 9.61 (MiG-29M2) and 9.31 (MiG-29K of 90s).
what these other aircrafts have any relevance with MIG-29. MIG-29OVT climbs and acceleration is not inhibited by heavier TVC engines despite they not have RD-33MK upgrade.
1- Did you measured the climb, turn or acceleration performance? 600 to 1100 km/h time? S/L climb rate? ITR? STR? To be very honest, I’ve always found OVT shows to be lacking the sudden acceleration and sustained turn performance of ordinary MiG-29, maybe related to the show planning IDK.
2-IIRC, engines did not recieve MK upgrade, instead they are RD-133s with new smokeless FADEC and uprated to 5600kg dry 9000kg, which was the basis of the RD-33MK?
3- Relevance? Like other aircraft, MiG-29 is built by man, and upgraded by man using present days technology. I thought it would be relevant to say there is no single example of a fighter that got lighter than the initial variant, after recieving several iterations of thorough upgrades.
AndraxxusI didn’t want to get into this kind of discussion but anyway…
MTOW has nothing to do with empty weight.
Really? MTOW and airframe lifespan is the MAIN factors that affect the empty weight. 7300 kg increase in mtow will require extra strengthening on the airframe, making it heavier. Ask it this way; Why MiG-29M cannot carry the additional 7300 kg but MiG-35 can?
MIG-29K carries about 5 ton of fuel for 2000km range. so show me any other fighter that can fly that far with this much empty weight to 2000km.
A claim both wrong in data and the proposition: MiG-29K carries about 4540 kg internal plus 2470 kg fuel on 3 external tanks (1x1500l + 2x1150l) to reach 2000 km range. 7010kg fuel for 2000 km range is not that impressive at all.
MIG-29M is lighter than MIG-29K and carries 6.5 ton external payload vs 3.5 ton for 9.12.
Are you comparing MiG-29M with MiG-29K or with MiG-29 9.12? Because i believe I’ve said MiG-29M is heavier than MiG-29 9.12 and MiG-35 will be heavier than MiG-29M. And then there is a funny fact that there are two 9.12s (9.12A and 9.12S with internal jammer), Two MiG-29Ms (M and M2), two MiG-29Ks (original K developed in 90s and the current one developed from MiG-29M2). Current MiG-35, MiG-29KUB and MiG-29K are mostly the same aircraft, developed from MiG-29M2 with larger wings longer airframe life etc etc. To think it will have similar clean weight of original MiG-29 is simply laughable.
MIG-29M superior engines, new FBW and larger wing area ensures that it is better in all flight regimes than MIG-29 9.12.
So you have the numbers for an aircraft that was never fully developed? You have the exact data that even MiG engineers don’t have?
If we compare F-16 blk30 and 50, there is 6% increase in empty weight. At sea level, sustained turn rate drops by 5-6% on average, despite 2,5% more powerful engine. MiG-29M has 9% greater engine thrust at the cost of 23% greater empty weight. If you think negative stability will make up for such increase in empty weight, you are mistaken. By the way, original MiG-29M does not have larger wing area, its same as MiG-29A. Even if it did, it woudn’t automatically translate to higher maneuverability that is a silly assumption too. Read what I wrote in #36. Or dont bother, I will simply say If MiG-29 was supposed to have higher OVERALL maneuverability (not even talking about ALL flight regimes) with larger wings, MiG engineers would have designed it so in the first place.
Andraxxuswhy you are including MIG-35 as it did not gain any weight and engines are enormously powerfull with new fbw. MIG-29 9.12 cannot compete with it.
MiG-29 9.12 = 10900 kg
MiG-29M = 13380 kg
MiG-35 is developed from MiG-29M, and has greater wing area (same as MiG-29K), and 7300 kg greater MTOW (requiring stronger airframe), and it carries more avoinics equipment (which adds to weight). Its empty weight is not disclosed (and I am sure even Russians dont know exactly what it will be), but it will quite possibly be heavier than MiG-29M.
AndraxxusPerhaps the fact that the Eagle doesn’t have any LE device like slats or LE flaps makes an increase of AoA during SRT more acute.
Sustained turns are not made at high AOAs. difference should be negligable. However as aircraft slows down at high altitude, percetage increase in the AOA due to weight increase also increases. Thats why F-15C has shallower STR curve than F-15A, despite more powerful engines. They both have same 8,5 deg/s maximum STR at around M0,9, but F-15 has more steep approach to the 8,5 deg/s mark, having slightly higher STR at slower speeds. As aircraft goes supersonic, overcoming the drag force becomes more problematic, and F-15C has superior STR at that point.
Generally speaking, I will tend to think that large platforms are far less sensible to MLU than smaller ones.
I disagree. A range upgrade needs room for fuel. Avionics upgrade needs room for the equipment themselves plus greater power needs. A larger aircraft can provide these more easily than smaller ones.
Take MiG-29 and Su-27, with each upgrade, MiG-29 get uglier, and SMT or UPG are total abominations with the bumps made for making “room” inside airframe. Su-27 variant tested canards etc, and Su-35S is looks exactly same as the Su-27S. Same comparison can be made for F-16A->F-16 blk60 and F-15A->F-15E upgrades.
Also smaller aircraft lose more performance with weight increases Blk30 F-16 had 23 deg/s STR. blk50 has 21,5. F-15E still has same maneuverability as F-15C, which has same maneuverability of F-15A, yet each variant has higher top speed. On the russian side, I don’t think MiG-35 will ever have the maneuverability of 9.12 MiG-29, but I believe Su-35 will have comperable maneuverability to Su-27S, despite all the equipment upgrades.
Andraxxushttp://www.prideaircraft.com/flanker.htm
you are refering to this. Made its first flight in USA in 10 December 2009.
We have gun cameras for even useless T-38 vs F-22 or F-18 vs F-16 or MiG-29 vs Su-27; which were not even publically available before someone put it on YT, yet there is no instance of F-22 vs Su-27 despite being shown on tv? Hard to believe… If there had been REAL hud video F-22 beating Su-27 in anyway (or vice versa) it would be all around the net, it would be even on the LM advertisments.
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