silverofx441

Hi! I would be interested for both Winwing controllers and possibly the MFD as well. What would be the price pls? Tx!

Yep! That's how we do heli logging here in BC.

Aaaaawww c'mooooonnnn!! This one came back!! Go to 3.06. [ame] [/ame]

Best explanation i have read so far on ANY sim forum. I'm ex-Airforce myself and i hold a "civilian" licence as well. I'm trying to explain to wifey (who flies with me) why it's hard to hold a nice steady climb after take off on a sim because im busy clicking the mouse all over the place. I have a G940 and i did assign a lot of things on my hotas such as gears, flaps, speed brakes, like most people i'm sure. Having purchased a Track IR made a huge difference because you don't have to play with your thumb on a hat to look around the cockpit and outside and it gives a much more natural feel when you fly. Best example i can give is when i flew choppers. In real life: no problems, In DCS? i do ok but you wouldn't know i'm a real pilot cuz i'm missing that "feel" more so during take off and landing. One thing: it's great for IFR training! No vertigo! (a vivid incident back in the '80's comes to mind here...) Anyhow thanks for this great reply. Gonna have the wife read it!

Yep! Same here, 2 within a few minutes. They both ended up in that sludge pit in the sky called file 13.

You didn't read my last post carefully. To quick to post to prove me wrong. I'm trying to give a simple explanation for the OP. You guys are trying to prove from A to Z with flashy words that you know better, AFTER i have given some explanations. That's very easy to do. I'm putting this to rest. You are more knowledgeable than me. You win. You can be assured from now on i will not try to give a bit of what i've learned and did back to the forum to help.

Oh boy... Just for you: here is where the difference between "closed" and "open" system comes to play. You are getting into the what would be more appropriate for a closed system. An open evaporative cooling system uses the principal of enthalpy of vaporization. In simple terms, it tells you about how much heat is necessary to transform a given liquid in to vapor at a given pressure. The best example would be a electric kettle. Most now are made of plastic. If you had no water in it, the plastic will be melted by the the element inside. But when you put water in it, turn it on, the plastic doesn't melt, why? Because a good part of the heat was transfer from the element to the water and the water released some of that heat as it evaporated. If the kettle was sealed pressure would built up quickly and so would the temperature. But it's open. It allows the pressure to remain constant and the water to evaporate releasing heat. But if you keep boiling the water, you eventually run out of it. Now replace that element with the radar array. The array gets hot as you use it. You pumped a liquid around it to allow heat to transfer in that liquid. The liquid gets heated to the point where it start to turn into a gas. That heated vapor has go to go somewhere otherwise pressure will built up and heat will remain within the airplane. The quickest and easiest way is to dump it outside. If you run out of liquid, well think about the plastic kettle; it will melt. On a closed system you will have more pumps, valves, heat exchangers, more pipes, injectors etc. That would enable the cooling system to keep the liquid as it cools it back into a usable medium for heat transfer. That's what you have on modern airplanes. But it's complicated, heavy, expensive and requires quite a bit more knowledge to fix it. I hope this covers it.

You are absolutely right. I guess you didn't read my last post carefully. And you learned thermodynamics where? Or are you just trying to stir the pot here? Ahhh i'm outa here.

That would depend if the system is built to be endothermic or exothermic. "in a nut shell" means just that, trying to keep things simple for the non-initiated. I could go into details on tons of aircraft systems if i wanted but that would defeat the purpose of the forum, i think, because most don't really need (or want) to know such details. A more broad general idea of a particular system is in the right tone, if you will. Plus i would be afraid that going into elaborate details would make one look like trying to show off or something. I'm not saying i'm above making mistakes, God forbid. It takes years to learn aircraft system and months to learn the particular systems of a specific airplane. It would be fallacious to think one could explain all that in a few sentences on a forum. Now if anyone makes a mistakes and is way off describing a system then by all mean, if somebody possesses real knowledge about it, join the conversation. But saying stuff like "i'll bet" instead off "i use to work on that aircraft" or something of that nature, makes it sound argumentative just for the sake of it to say nothing of the fact that it makes it sound like a guy just googled it instead of having real knowledge. All that said in a respectful manner with absolutely no intention to insult anybody, off course.

There will be a vent on both closed or open system. On the closed system, it's an over pressure safety device. On the open system it's necessary in order to produce the amount of evaporation needed for heat transfer. Alcohol is way more efficient in transferring heat than water, because it evaporates faster and have a lower boiling point. The con of such a system is gradual loss of alcohol as you use it. But very simple, efficient,cheap, trouble free and if having to refill it after each flight doesn't create undue logistical problems, then sure, a good idea. In a nut shell, alcohol is routed (pumped) around the radar array with tubes. The alcohol being cooler than the radar, the heat will transfer to the liquid. The liquid will keep going til it gets to an expansion chamber, if it were. Evaporation will occur and heat will be dissipated as it is vented out in the atmosphere by it's own pressure create as a byproduct. Very simple system, a fraction of the parts (and cost) needed compare to closed circuit. You can also see an advantage in weight and space saving here. You could always tell that Russian designers were very practical and ingenious and had to work within constraining limitations. The ruling parties were forever demanding better design but with a fraction of the money that would be available to western countries. They wanted maintenance to be idiot proof so as to shorten training time and enlarge the pool of potential candidates for technical schools. They wanted super reliable airplanes to minimize downtime between flights. On top of that, their aircrafts had to be able to operate at temperatures ranging between -60 to plus 60 Celsius. And lets not forget crappy unprepared landing strips as a requirement in case it becomes necessary to deploy some jets in remote areas. All in all, i think these guys did (and are doing) pretty good.

I did mention the limitations of air cooling, it's a minimal safety feature. It's an actual system on most jet fighters. There are two ram air scoops on the F-18 for that purpose.

The radar cooling system was solely used for the radar. The radar is not a "flight essential system" if it fails or is used in passive scan mode, then you have no way of heating the fuel. That's the job of the ECS or the Environmental Control System. It takes compressed air from the engine (bleed air) which is at about 600 F. So as long as one of the engine works, you got ECS. The radar cooling system is independent with virtually no redundancy. In case of failure, ram air will be used to cool it, but it limits the time you use the radar (if at all) in it's most powerful mode. If it failed (very rare) the mission was aborted and the ram air system was to make sure the whole thing wasn't going to fry completely. Pressurized air, about 5 psi if i remember correctly, is also used to cool avionics including the radar's. (we are talking about modern 80's jet here)

It could be interesting to know that Canada was using, more or less, the same method. We had what we called the "Dew line" and the "Frost line". The were two lines of radar stations spread across the country form coast to coast. The "Frost line" was fairly up north (hence the name) and was what we referred to as the the first line of detection. The "Dew line" was lower and was the second line of detection and was used for monitoring traffic in the lower part of the country. So for the same reason as the Russians, very large area to cover (they have the biggest country in the world and we happen to be the second!) budget restrains etc, it is way more cost effective to have lines of long distance radar to monitor airspace intrusions, with fewer squadrons of interceptors based in strategic locations, than having a bunch of units spread all across the map. Our respective countries are too big, period. So, say a intruder was detected, they would scramble usually 2 planes (in peace time), they would be vectored towards the appropriate direction. The intercept officer sitting in the back would do a search in passive mode and when he was fairly sure that they were in good position, he would turn the attack radar on, lock his target, fire, go home, have a beer at the officers mess. The plane we used was the somewhat crappy "Voodoo" or CF-101 (one-o-wonder). But that thing was a frikking fast climber if not a good dog fighter. P.S. My apologies to the OP, it seems i have "stolen" his thread:music_whistling:

As a matter of fact, the alcohol used for cooling purposes was of a better quality than most vodka consumed. It was perfectly safe to drink. A nikcname for the Mig-25, for example, was "the flying bar" because of the very large quantities of the stuff it could carry due to its size. Which is why the Mig-21 has a fairly limited usable amount of time for the radar: small aircraft, less space for storage of equipment liquids etc. But what we were told back in the 80's is that the USSR, Which was using intercept tactics based on the GCI model, would scramble a flight of interceptors, they would be guided manually or automatically in the vicinity of the target, and only then the pilots would turn their radar on, lock a missile and destroy the target. That would minimize or eliminate the chance of being detected by the target before they could get into a good firing position. Based on that, there was no need to develop a long distance radar and it would be used for fairly short amount of time.