DarkFire

Good point. This may be going slightly O/T, but if it were suspected that an airframe had been subjected to extreme over-G I'd expect it to be shipped (literally, not flown) to a 2nd line maintenance base where it would be totally stripped down to the bare airframe for inspection, or at least stripped down to the point at which the entire frame would be accessible. Then comprehensive testing, possible replacement or rebuild of entire sections of the airframe followed by reconstruction of the entire aircraft. I'd be amazed if the pilot saw the aircraft again within 3-4 months. If the RuAF is anything like our lot, and I'd be amazed if they were not, then during such a deep inspection & rebuild absolutely everything is inspected down to the smallest detail and are very carefully re-constructed, tested, tested again, tested some more just to make sure and then inspected again to make sure. Only then would the aircraft be subject to further test flights before being finally signed off and released back for line squadron use. Deep inspection / maintenance cycles are taken very, very seriously because so much is reliant on them: the life of the pilot and the national investment in an expensive aircraft. Referring to the 2nd image that CiberAlex posted, I take it that the 5Km, 10Km, 12Km and 15Km lines on the G v Mach diagram refer to operating altitudes? That's really, really useful information to have, thanks for cross-posting from the Russian forum :thumbup:

This is purely guesswork on my part, but what I imagine is that the airframe has a certain quantity of "health." Any G conditions then remove varying amounts of that health based on the amount of G, with higher amounts of G removing much more health than lower amounts of G, and over-G conditions removing much more. I'm imagining some sort of y = x^4 relationship between degree of G and the amount of "health" removed, i.e: Hcurrent ~ Hmax - k where k : (Gcurrent/Gmax)^4 This would account for the fact that severe over-G can subsequently result in destruction at what are ostensibly lower G values than the normal limit. I could be wrong about all of this, but I suppose it might fit the observed behaviour.

We regret to inform you that your sons are dead because their vision was obscured by a caffeine administration receptacle (or in old-school British military parlance a "cup, coffee, drinking, for the use of") :lol: Some really good information in the last few pages, thanks everyone for sharing, I've learned a lot :thumbup:

Very impressed that you managed to get that bird down in (most of) one piece! Surprised you didn't jettison the stores on the undamaged wing though - that might have reduced the differential lift a bit. Damned good piloting nonetheless :thumbup:

The real Su-27 does have G and AOA limiters but apparently they're only actually programmed to take weight of stores, fuel etc in to account on the most recent versions, e.g. Su-30MKI, Su-35 etc. Russian "generation 4" aircraft have historically been designed this way: they often don't have artificial limits on what the pilot can make the aircraft do, but then expect the pilot to know how to, and be able to, operate within safe limits. The theory is that not having care-free handling enables more experienced pilots to get more performance out of their aircraft than would be the case if they had care-free handling characteristics. The flip side of the coin is that the aircraft are more dangerous for less experienced pilots since it's possible (and relatively easy) to take it way outside the structural safety limits.

This. There's a difference between line squadron pilots and the elite test pilots who we see doing insane things during airshow routines. Pilots like Anatoly Kvochur, Viktor Pugachev et al are the top 0.01%. I'd bet that most line squadron pilots are instructed never to touch the direct mode switch in any circumstances outside of a failure of the FCS system, precisely because it represents such a risk to the aircraft and the pilot.

Same again today. Same circumstances. Game log attached.

OK, here's a quick and dirty test I did. Conditions were a standard DCS day, no wind, no clouds, no precipitation. Load: 100% fuel, 100% gunpad, 100% expendables, 2x ECM, 2xR-73, 2x R-27ET, 4x R-27ER. I did a series of turns at IAS from 450 to above 1100. max G was between 7 & 9 on each occasions. I also did a high speed barrel roll & some tight-ish loops. Airframe failure did not occur. Su-27 G Test ACMI.zip Su-27 G Test Track.zip

It's worth noting that metal parts, when exposed to repeated strain above their designed load limit, are then very vulnerable to subsequent plastic failure at well below the same design limit. This is entirely physically accurate. Reference: The Behaviour of Metals Subjected to Repeated Stresses H. J. Gough and D. Hanson Proceedings of the Royal Society of London. Series A, Vol. 104, No. 727 (Nov. 1, 1923), pp. 538-565 Published by: Royal Society Stable URL: http://www.jstor.org/stable/94221 The introduction of overload failure of the airframe will require us all to adapt our piloting, but then the Su-27 (and other Russian aircraft) have never been designed with care-free handling built in. It's always been the responsibility of the pilot to fly within safe limits. The design philosophy seems to have been not to place artificial limits on pilot input to enable a knowledgeable and skilled pilot to go beyond what would otherwise be possible.

I'm genuinely not seeing too much of an issue with this update. Even at near 100% fuel with a full A-A weapons load it's still perfectly possibly to slow from cruise speed down to corner speed with a max-ITR turn and then concentrate on STR turning for WVR fighting. Maybe I'm doing it wrong, but using the 'slow is smooth, smooth is fast' approach rather than banking & yanking seems to work just fine. I guess there's a reason why in the real flanker it's necessary to throttle way back to expose the direct mode switch cover...

I'm experiencing the same, or what appears to be the same bug. Every. Single. Time. I play on the VA server the game ALWAYS disconnects and crashes when I try to re-connect with a "DCS is not responding" problem. I'm using the vanilla game with no mods and have all my drivers up to date. This has crashed for me under these conditions something like 5-6 times today alone. Attached are the two most recent crash logs. Not sure if it has anything to do with the issue but the server is running some form of lua script. Edited to add: Reading the other crash threads, this server is also running dynamic weather. Wonder if that has anything to do with it because the game doesn't crash at all in SP with static or no weather settings. Further edited to add: Windows 10 event viewer produces the following critical error information: Faulting application name: DCS.exe, version: 1.5.3.52018, time stamp: 0x5706392d Faulting module name: Weather.dll, version: 1.5.3.52018, time stamp: 0x57052915 Exception code: 0xc0000005 Fault offset: 0x00000000000036fa Faulting process ID: 0x2390 Faulting application start time: 0x01d192c8d7a706e8 Faulting application path: C:\Games\Aerospace\DCS World OpenBeta\bin\DCS.exe Faulting module path: C:\Games\Aerospace\DCS World OpenBeta\bin\Weather.dll Report ID: fa339130-420e-4ba9-80bc-21b8ef8a91ab

I guess that would make sense if the data in the table represents safe operational limits, whereas the airframe may or may not be capable of more, with the possibility of structural deformation etc as G increases over the safety limit. I remember reading a book which included a section on the MiG-29 which explained that while the G-limiter is set to 9, the airframe can survive 12 or thereabouts. Obviously may be different for the Su but it would make sense for the operators manual to give max G figures that have a built-in safety margin.

This. unload - roll - load is nearly always faster. If you watch cockpit video of most MiG-29 or Su-27 pilots on YouTube, watching carefully this is exactly what they do. Airshow routines will be different but they fly with very light fuel loads so structural G limits are much less of a concern.

Excellent, thanks very much! Some weight data for the purposes of calculating max G: 100% fuel, no external weapons, 100% ammunition & expendables: 27,116 Kg. 50% fuel, 4xR-73, 2xR-27ET, 4xR-27ER, full gunpad: 24,942 Kg. 75% fuel, missile load as above & full gunpad: 27,292 Kg. 100% fuel, missile load as above, full gunpad: 29,642 Kg. 100% fuel, 36xFAB-100, 2xR-73, ECM, full gunpad: 31,596 Kg. So as an example, if you're at cruise RPM (85%, normally produces ~0.95M clean or .85 with a high drag load) with a max bomb load, your structural maximum load will be all the way down to 5.4G.

Not by any means a definitive answer, but it feels like it's now easier to incur damage to control surfaces or to the wings during low speed collisions, e.g. taxi accidents, failed take off attempts, heavy landings etc. I spent a few hours tonight on the virtual aerobatics server & there were aircraft parts all over the runway at Pashkovsky from people trying to land at 350 Km/h or trying to take off 1m behind other aircraft (I'm looking at you, whoever you were F-15 pilot) :lol:

Is there a table in the manual that shows max G against aircraft gross weight? Any chance you could post the info here?

This. I'm sure that eventually load damage will be modelled for all the DCS-level modules.

Looks like it may need a slight bit of tweaking in terms of unusual conditions producing incorrect overloads on the airframe, but in general this is a very good thing. No more unrealistic high speed >20G turns using direct control mode, yet direct mode is still viable and useful at lower airspeeds. Nice!

Good point. I'd also recommend using 15-20 curvature for both pitch & roll so that you can accurately place the target piper. One more thing to remember - the Russian RBK cluster bombs don't have a set function altitude, they seem to operate purely on a timer, so increasing release altitude will increase the area of coverage and vice-versa. Pages 80 - 88 of the Su-27 flight manual gives good descriptions of the various weapons available and the types of target they can be usefully employed against. Something to bear in mind though is that in DCS fragmentation from warheads is not modelled - only blast which decreases from the point of explosion as ~ 1/r^3. Thus blast frag warheads won't be anywhere near as effective against targets like troops in the open as they ought to be.

Yes, good point. The TWS mode is totally disabled in an ECM environment whereas I think TWS mode on the F-15 still works..?

This looks like fun, I'll definitely give this a try!

I'll take this from my point of view, hypothetically flying against you in an Su-27, which will probably be your most common & dangerous 'red team' opponent. The two things that ECM hides are your range and altitude. The range comes with a caveat: when my radar achieves burn-through the ECM is useless as I can then lock you up despite the ECM. It also sort-of masks your aspect but if I'm paying attention I can take a fairly educated guess on your aspect by changes in the bearing rate of the ECM strobe on my head-down display. If we're approaching each other head-on my radar will achieve burn through at almost exactly 40 Km range, which puts you well outside of Rtr range for my R-27ER. I think the radar in your F-15 will achieve burn through at a slightly longer range, but this will also be outside of the optimum launch range for your AIM-120B/C. Masking your range and altitude does give you options though: if I have my radar on, which is being detected by your RWR system, unless I'm flagged as a primary threat then it might be safe to assume that my radar hasn't burned through your ECM yet. This means I won't be able to tell if you change your altitude, nor will I know exactly what range you're at. Do you chose to climb up high and hope that I'm not scanning upwards with my radar? Do you chose to drop down in to the weeds so that my radar suffers a ~25% detection range degradation? Maybe you want to duck in to the terrain and set up a short range ambush for me. Very dangerous thing to do against an Su-27, but if I can't find you maybe you'll be able to launch against me giving me insufficient time to evade the missile. ECM is of course highly situationally dependant. The one major down side to using it is that it will reveal your presence and bearing to a range well in excess of the range at which my radar would be able to get a primary skin paint on your F-15. I'd normally be able to detect you out to ~100Km head-on, but having ECM on will reveal your presence way out to the radar horizon. I'd say that ECM can be useful in order to deny an engagement from a reasonable range (say ~45 Km and above) but at anything under burn-through range it becomes useless. It can also be a severe disadvantage under certain conditions: if I'm wandering around at low level with my radar off, and your jamming strobe appears on my head down display, I can use the bearing of the strobe to potentially go around you and carry out a stealthy attack from behind using my EOS. A note on realism: apparently the built-in ECM on the Eagle has severe heat generation problems and eats up ~80% of the cooling capacity of the entire aircraft. Though some people do it, turning on the ECM 5 seconds after takeoff and leaving it on would appear to be highly unrealistic. This would also of course broadcast your presence for miles around as described. The good thing for the F-15C is that the ECM is built-in, whereas if I want to use it on my Su-27 I have to sacrifice two of my R-73 missiles. Harder decision.

It depends largely on the situation. Both CCIP and CCRP are available, though due to the size of the piper CCRP tends to be less accurate than CCIP. A good technique is to roll in at something like 7,000m altitude and release at anything between 2-4,000m. The steeper the dive the more accurate the release tends to be, though you do have to be careful about your speed building up in the dive. Because all the A2G weapons on the Su-27 are unguided I really wouldn't recommend taking on any targets that have any AA defences more advanced than a ZSU-23-4 and even then, maybe. There is another highly unusual bombing technique for defended targets which involves approaching the target at Vmax (usually around 1,200 Km/h TAS) at around 1,000m altitude, releasing in CCRP mode then doing a max-G turn to avoid overflying the target. Supersonic bombing like this is amusing but tends to be rather inaccurate and uses up an awful lot of fuel. Happily as of a recent patch the Su-27 will release bombs (including RBK cluster units) in matched pairs so you won't have any asymmetric trim issues. 500 - 600 Km/h in a 40 - 50 degree dive usually produces the best results for bombs.

Definitely the way to approach DCS. It's a sim that rewards patience, time and effort. If you consider how long it takes a real air force pilot to learn a new aircraft (a conversion course might be anything from 20 to 100 hours) then it's a safe assumption that most of the aircraft in DCS will take a similar amount of time in which to become proficient, and then the usual 1000 hours to really understand. Never be afraid to ask questions though - many of the members of the forum have more time in their favourite DCS aircraft than AF pilots have in the real thing. This is also probably the most friendly and helpful game forum I've ever been a member of.

I'd also heavily recommend getting Tacview: http://tacview.strasoftware.com/product/about/en/ It's probably THE most useful tool for evaluating your own performance, see what went well and what didn't in any given situation and how to improve next time.