Griffin

They are abbreviations.

But you need to face the threat until the end, not getting warned of being shot at (except for laser) and before that you had to find it without a FLIR while navigating and planning at the same time. That's too much multitasking in an outdated helicopter. Apache can find the targets much more safely, plan a more effective attack, turn away after shooting and getting a warning if shot at. LOAL is also an option when the target is being lased by another source. With modern technology the Ka-50 could be turned into an awesome one man fighting machine.

Hi and welcome! I don't yet have first hand experience in current generation DCS PC's but I'm in the process of building one. With that 1000$ you will get an awesome machine. One thing I suggest is to wait a couple of weeks for the new Z97 chipset motherboards to be released (unless you live in US where they are going to be out on sunday at latest). They will enable you to upgrade to Broadwell CPU's after they are released in the end of this year or next year. They also don't cost any more than the current Z87 motherboards. That's what I'm doing, I'll buy a Z97 motherboard with a current Haswell CPU and will have the provision to upgrade to a more modern Broadwell CPU in a couple of years if I wish so. Some general rules of thumb I've learned (though correct me if I'm wrong): - Get a graphics card with the most of video memory as DCS is very hungry for it. - SLI/Crossfire is currently useless in DCS. EDGE might change that. - SSD is a must for any computer these days. Samsungs are quite good and for a very nice price. - AFAIK 8GB of RAM is enough currently but EDGE might change that too so 16GB could be smart. What do others think?

Although the problem with damage modeling is evident, a Stinger/Igla is not guaranteed to bring a helicopter down. There is a video of a Syrian Mi-8 getting hit but flying away just fine. On the other hand, Ukrainian Hinds have been shot down with a single hit. The kinetic energy from a tank round should be enough to destroy a helicopter even without an explosion. I'm not an expert though.

According to THIS and THIS article, the Z97 boards will be compatible with 4th generation CPU's meaning that I should probably wait for a couple of weeks and get one of those, MSI Z97 Gaming 5 to be exact. It will cost a bit more but in a couple of years I could easily upgrade to a Z97 CPU. It's not really so black and white but gives some idea. In some cases the 8320 does beat the Intel but overall Intel seems to win.

The AMD front sure looks very tempting with the lower prices. But isn't that because they are older than the Intel counterparts? Is there some new AMD technology right around the corner? I know it'll cost more when it's out. AMD seems to have some drawbacks mainly because of the 50% higher power consumption. What I would save in the CPU/MoBo price, I would have to use for a new cooler. That's due to the eight cores vs four I suppose. Besides, more cores won't help me in games currently especially in DCS. I'm sure theyr'e great chips but there is some evidence that gives Intel the edge and with a new cooler, the price difference is non-existent. http://www.cpu-world.com/Compare/443/AMD_FX-Series_FX-8320_vs_Intel_Core_i5_i5-4670K.html

Thanks for clearing it up lunatic. I have Gigabyte Radeon HD 7870 Windforce 2GB so I think it should suffice for now. I'm running only one monitor 1680 wide. The CPU can't take the OC anymore as the temperature rockets up. I think it's getting old and it's time for a new core. Do you think the preliminary Intel kit could handle Oculus Rift with the HD7870?

I sure hope it does. It would save me a long penny! Pardon my Finnish. Here's a preliminary Intel kit. I'll check out what AMD has to offer thanks to SkateZilla for making this difficult. ;) MSI Z87-G45 Gaming Which fits the budget just well. 130€ Intel Core i5-4670K For being the best bang for buck according to THW. 204€ Kingston HyperX Genesis 8GB 1600MHz CL9 XMP I assume getting higher frequency RAM will not benefit me really. I hope these take basic overclocking well when I decide to do it in the future. 80€ = 414€

Thanks Rangi. This is important information and I'll go on from this base if I still have enthusiasm to upgrade a couple of weeks from now. Thanks for contributing anyway Maximus. My Kuhler will definitely have to step aside if I decide to overclock properly.

That's true but do you think they will still have the same socket? I wouldn't want to buy a core that can't be upgraded with a new CPU in a couple of years if need be. I've actually dreamt of the balcony air intake but it's not possible in our current room arrangement. It would also bring problems with filtering the air and condensation/carburetor icing. ;)

I have Saitek pedals waiting to be scrapped in my closet. I could dig out the part and send it to you? It'll only cost 1.5€ and you wouldn't even have to pay me back. If you pay for postage, I'll send you the whole damn pedals for spares!

Two or maybe even three Ukranian helicopters shot down. One is Mi-24. Missile explosion in the beginning? http://www.youtube.com/watch?v=-UmqzweOlPQ

I think I'm having enough of my old Q9550 rig which isn't enough for modern games even overclocked and I even had to reduce the overclock considerably due to skyrocketing temperatures. Seems like the CPU just got enough of the years running overclocked. So I need a new core for my PC ie. CPU, MoBo and RAM. Choosing the CPU seems quite easy as Tom's Hardware gives the best for the buck, right now being the Intel Core i5-4670K in the 200€ range. RAM is the second easiest. It should also allow basic overclocking, nothing too fiddly, so I think Kingston HyperX series RAM will have enough headroom while being affordable. Choosing a motherboard seems like the most difficult part as there are millions of options to choose from. This is where I need help. Let's say my budget is 150€ and it should allow basic overclocking. Questions regarding the above: - Is the i5 CPU still modern enough with a socket that will live on for a while? Or should I wait for some new technology to be released as I'm not in a particular hurry and ignorant of the current developments. - Is 8GB of RAM still enough for sims (DCS, IL-2 BOS) or should I get 16GB? The i5-4670K has a bit lower Thermal Design Power than the Q9550 so I think my Antec Kuhler 620 cooler will suffice at least for the time being before I start overclocking at a later time.

Fake. The explosion sound doesn't even have a delay. Terrible editing and the original footage is probably Syrian as Namenlos said.

+1

Yeah sorry for that. Just had to make sure I didn't misunderstand which I did. :) I agree 100%.

By the the airfoil shape, do you mean that they are curved to optimally direct the airflow? I'm asking because in my mind an airfoil (shape that's thicker in the front than rear) doesn't have to be curved to be an airfoil. Some aerobatic planes use a symmetrical airfoil wing which has no curve. So it confuses me as in my mind, airfoil shape is exactly what creates the diffuser by being thicker in the front. I don't mean to be a smart ass, just trying to clear confusion. :) It's interesting by the way how hard it's to see the thickness difference of stator vanes with bare eyes. Just looking at a stator stage doesn't make me see the obvious diffuser there. They are so thin that they just look like flat plates without creating a divergent path. Amazing how subtle shape creates so much compression.

If no stator vanes would be present the velocity would indeed increase in a converging duct. But compression reduces volume. If the duct wasn't convergent, the air would slow down considerably. Converging duct keeps the total velocity constant by keeping the space/volume ratio constant for the ever more reducing volumes of air. I think I could explain it a bit better but I have to leave work in just a moment. Maybe the Jeppesen book has a nice picture of the angle? Maybe this video would clear it up a little? Also the first few stator stages have a variable angle to keep the airflow optimal. They are called variable inlet guide vanes and variable stator vanes.

That sounds quite correct although I'm still learning here too. It's nice that people comprehend things differently which forces me to think stuff from different perspectives. I had to really process that text! This is true for the rotor part. The compressor rotor blades add kinetic energy to the air and shove it backwards. The compressor stators do the opposite by converting the kinetic energy into pressure, thus slowing the air down. The total velocity of the air through compressor doesn't increase, so the quoted part doesn't apply to the compressor section as a whole. Also the (high pressure) compressor rotor doesn't really apply a significant force to the engine structure because it may be cancelled by the turbine (depends I guess). However the compressor stators do apply significant thrust forces to the casing.

You are really on the right track in a way as afterburning reduces the rearward thrust forces acting on the nozzle. It's really confusing to me as how the hell can the nozzle that produces the final thrust of the engine actually create rearward forces on the engine. Really counterintuitive despite understanding the theory behind it. The rearward thrust forces come from the pressure differential in the jet pipe vs free air as far as I understand. However afterburning doesn't reduce the rearward thrust forces by reducing or increasing the pressure, but with the acceleration of the gases. From RR book again: Sorry, I didn't think all the way through the jet engine all the way back to the afterburner nozzle. I've been so narrow sighted trying to understand individual parts of the jet engine that I forget the rest parts and their variations. Of course talking about afterburners involves choked and convergent-divergent nozzles (about which I refused to talk about). So far the best book explaining the operation of the jet engine has been Jeppesen's Aircraft Gas Turbine Powerplants, which unfortunately I don't have physically, yet. This isn't so much about lecturing other people as much as it's useful to me to write things down as it forces me to put it out in an understandable form, thus clearing the picture to myself. Please correct me if you see something wrong. EDIT: If the attachements were deleted on purpose then please tell me so I won't do the same mistake again.

Ah, thanks guys! Makes a lot more sense. See, the last time I did this was in school so while it's simple and very basic, I just don't remember. :doh: I don't mind as I'm pretty fluent in imperial units and use pounds and horsepower instead of Newtons. Should propably get used to the SI system like the rest of the world. The book edition is from 1986. Yeah the typo appears on two equations on the first page of calculations and is corrected on the rest of four pages.

Do we have someone here good with physics or maths? I have a question regarding jet engine thrust. Rolls Royce The Jet Engine book (1996 print) gives the following thrust equation: This is easy to work with especially since there are great examples of calculating thrust for the whole jet engine. This equation is also the same given in a Boeing presentation. However the latest Rolls Royce book gives the following equation: F = W (Vjet - Vflight) + A (Pexit - Pinlet) And NASA gives (essentially the same): F = (m dot * V)e - (m dot * V)0 + (pe - p0) * Ae EDIT: The two last equations are basically the same as the first one without the gravitational constant. At least so I believe. Might be something I'm missing. So the old RR book and Boeing give the equation with a gravitational constant but the latest RR book and NASA give the equation without it. NASA gives a good explanation of the equation breaking it down before combining it to the above form but nowhere there is a gravitational constant. The latest RR book doesn't explain it at all. It goes without saying that without gravitational constant the result of the thrust equation is not the same so I can't use the NASA and latest RR equation to calculate thrust. So what am I not understanding about the NASA method? Why is there no gravitational constant and why is it needed in the first place?

Holy crap that was awesome! Great editing and footage! MOAR MOAR!

In order to understand the internal operation of the engine, you must understand Bernoulli's law. You understand how it works with the wing but it can be counterintuitive when thinking about internal engine operation. It states that when there is a convergent duct, the pressure drops and the velocity is increased. Thus afterburning doesn't increase pressure inside the jet pipe nor does it increase the engine pressure ratio (EPR). If it did, it would be working against the rest of the engine which is trying to accelerate air backwards to create thrust. It's also a common misconception that there is an increase of pressure in the combustion chamber, which is not true. From Rolls Royce The Jet Engine book (1996 print): "The nozzle is closed during non-afterburning operation, but when afterburning is selected the gas temperature increases and the nozzle opens to give an exit area suitable for the resultant increase in the volume of the gas stream. This prevents any increase in pressure occurring in the jet pipe which would affect the functioning of the engine and enables afterburning to be used over a wide range of engine speeds." "The effect of afterburning is to increase the volume of the exhaust gases, thus producing a higher exit velocity at the propelling nozzle." While thinking about thrust distribution and the conditions (P, V, T) in different parts of the engine, the big picture must also be remembered as total thrust equals the sum of internal forces at different stages of the engine. And thrust results from acceleration of mass, not creation of high pressure behind the engine. Pressure plays a role but it's a small one. Some engines may operate with the nozzle in choked condition which brings additional thrust from pressure. But since it doesn't apply to all jet engines, I won't go into that. Here's a picture from the RR book. It shows the thrust distribution in all parts of the RR Avon engine. It's a bit misleading though as it doesn't show compressor and turbine stators which transmit thrust to the engine case. The rotors on the other hand act through the thrust bearing but it's not so simple as there is thrust balancing involved in the rotor system. So thrust acts throughout the engine imposing forces on the structures. I won't claim to understand it completely either as I'm not an engineer and there are a couple of counterintuitive things that I haven't yet figured out.