DCS FC3 Questions & Answers Thread

I'm waiting the Mig-29S separate module. When is the release?

Soon ™

Guys I need help! I installed DCS 2.2X I have the Nevada map, I can play quick missions and instant actions, but there are no campaigns, is this normal or something is wrong?

To the best of my knowledge, there are no campaigns included with the Nevada map. There are only user created or purchasable ones from the DCS website.

PFM for Mig-29

I think an upgrade to PFM for the Mig-29 shortly after release of the Hornet would be timely considering those two aircraft are good opponents for each other in terms of capability and performance. But what do I know. I'm just a meathead.

any news at all about the MIG-29? After the SU-33 came out they said the MIG was next for PFM

Hello. I have a question. I own FC3 on my 1.5 for Steam, and I own Su-27 on my 2.2 for Standalone. If, when I update to 2.5, I install both, and not just FC3, will the Su-27 icon, at least, remain? They all disappear when FC3 is installed, which is annoying. It'd be really nice if, not only did they not disappear, they got lit up and I could put up the wallpapers! But, the main question is, will the Su-27 icon stay there?

why does speed decrease as altitude increases?

Good question this is explained by the "Custard Layer theory" Which is the empirical proof that the Air gets thicker as altitude increases ... slightly controversial concept but pretty simple. (Note this theory predates Global Warming theory)

Take your oblate spheroid (Planet earth) and wrap it with an atmosphere (The custard layer)

then rotate the oblate spheroid around its axis ... what happens to the custard layer ... it gets thrown off ...as does the atmosphere.

Nonsense you say .... but lets look at the evidence.

Why is it that (if you accept the theory) that slow aeroplanes that fly in the lower reaches of the custard layer have propellers ? simple the air is so thin they actually need fans to induce air flow. Helicopters who indulge in super thin air "nap of the earth" type flying have the biggest propellers of all.

As you get higher the air gets thicker so thick in fact that propellers can no longer turn so then we bring in jet propulsion which allows thick air to be accelerated through a tube to produce thrust. then of course you get into space were its so thick you cant even get the air down a tube so must resort to non air breathing engines like rockets.

Take also the pilots those who fly in the lower thin portions of the custard layer can breath quite easily unassisted. however as you get higher the air is so thick then masks and ultimately full pressure suits are required ... least the high altitude aviator drowns in the thicker higher level air

Further convincing proof of the theory is the colour of the sky. in the lower thin levels is a lovely cyan sky blue ... however as you climb the sky gets darker until ultimately in space where its really thick its black ! ... pretty convincing so far.

Now of course there many other empirical proofs but lets get back to your question.

"Why does speed decrease with altitude" ... simple in terms of Custard layer theory . Given airspeed is measured by Pitot static systems in the lower or thin portions of the atmosphere the air molecules are free to move and their concentration is obviously less so they can rapidly move through the pitot system. However as altitude increases the air becomes thicker and poor air molecules become congested and constrained by the pitot tubes and can no longer move through it as quickly as at the lower levels and so a lower speed is registered.... all quite simple really. It just takes a little outside the box type thought see the answer.

BTW "Custard layer theory" also explains why Chem trails can linger so long after they have been dispensed .... but much of that subject is of course classified.

Anyway I hope that brief discussion on "custard layer theory" helps answer your question :)

However as altitude increases the air becomes thicker and poor air molecules become congested and constrained by the pitot tubes and can no longer move through it as quickly as at the lower levels and so a lower speed is registered.... all quite simple really. It just takes a little outside the box type thought see the answer.

Not saying your wrong but that goes against everything I've ever learned. I've always been taught that air gets denser the LOWER you go because of other molecules above pushing them down. And that air gets thinner/less dense as you increase altitude so that's why mountain climbers have trouble breathing?!

why does speed decrease as altitude increases?

Your IAS will drop because the air pressure in the pitot tube drops. TAS will stay the same. You can actually go a lot faster at high altitude because of less air resistance, e.g. in the F-15 you'll struggle to go above Mach 1.1 at see level but can be above Mach 1.4 at 40.000ft in no time.

Your IAS will drop because the air pressure in the pitot tube drops. TAS will stay the same. You can actually go a lot faster at high altitude because of less air resistance, e.g. in the F-15 you'll struggle to go above Mach 1.1 at see level but can be above Mach 1.4 at 40.000ft in no time.

Sorry but what's the exact difference between IAS and TAS?

Sorry but what's the exact difference between IAS and TAS?

TAS or True Air Speed is how fast the air is actually moving over your aircraft's control surfaces (or how fast your are actually moving through the air). As such, you need to know it when trying to calculate closure speeds, for instance. IAS or Indicated Air Speed OTOH is, in a sense, is a measure of how much air is actually moving over those surfaces. IAS is an indication of how your aircraft will respond to that air. At high altitude, you can be moving fast (TAS) through the air but your aircraft can be just above stall speed (in terms of IAS) because there is so little air to provide lift, etc. You fly the aircraft in reference to IAS. How the aircraft feels with an IAS of 250 at sea level is more or less how it will respond with an IAS of 250 at 32,000 feet, even though at 32,000 feet, your true speed through the air is 800.

" How the aircraft feels with an IAS of 250 at sea level is more or less how it will respond with an IAS of 250 at 32,000 feet, even though at 32,000 feet, your true speed through the air is 800"

actually its behavior is very very different, aerodynamically its at 250 but inertia is there for the very much higher TAS. The aeroplane is a lot more sensitive at the higher altitudes tasks like close formation are a fair degree more difficult at higher altitudes even at the same IAS as aircraft inertial response is TAS based. To the pilot the aeroplane feels a lot more squirrly at the higher altitudes than the lower altitudes. For the same IAS you can manhandle the aeroplane a whole lot more at the lower levels than you can at the higher levels.

" How the aircraft feels with an IAS of 250 at sea level is more or less how it will respond with an IAS of 250 at 32,000 feet, even though at 32,000 feet, your true speed through the air is 800"

 

actually its behavior is very very different, aerodynamically its at 250 but inertia is there for the very much higher TAS. The aeroplane is a lot more sensitive at the higher altitudes tasks like close formation are a fair degree more difficult at higher altitudes even at the same IAS as aircraft inertial response is TAS based. To the pilot the aeroplane feels a lot more squirrly at the higher altitudes than the lower altitudes. For the same IAS you can manhandle the aeroplane a whole lot more at the lower levels than you can at the higher levels.

You're right, of course, which is why I said more or less. I simply wanted to get the idea across that IAS had more to do with how the aircraft handled, while TAS had more to do with speed/time calculations.

Not saying your wrong but that goes against everything I've ever learned. I've always been taught that air gets denser the LOWER you go because of other molecules above pushing them down. And that air gets thinner/less dense as you increase altitude so that's why mountain climbers have trouble breathing?!

Custard Layer :)

To answer your question in it’s simple form, less dense air will result in a lower differential pressure between the pitot tube and the static ports (and hence lower IAS) for the same true airspeed as pressure altitude increases.

Some things on airspeed you might want to know,based on your question. Thanks Ironhand :)

The definitions I use are:

TAS is the actual speed at which the airplane moves through the airmass that surrounds it.

IAS is the speed observed on the air speed indicator.

Just to be clear.....

The airspeed indicator utilizes the difference between pressure measured at the pitot tube and the static port(s) to measure airspeed. This airspeed indicator is designed around a sea level standard atmosphere.

The airspeed indicator is subject to instrument and position errors. If you could correct for these errors you’d have CAS, which stands for CALIBRATED airspeed.

Another way to define TAS is as CAS corrected for nonstandard temperature and pressure. So as you go higher and the air is less dense, you will actually have a higher TAS than CAS, which IAS tries to display. CAS = TAS at sea level in a standard atmosphere.

Just to complicate things, in high speed airplanes, you also correct CAS for adiabatic compression flow. So when you get high and fast, air is compressed at the pitot tube giving false readings. If you correct CAS for this compressibility then you get EAS, which is called equivalent airspeed.

If you really want to get deeper into this kind of thing get yourself a copy of “Aerodynamics for Naval Aviators”

Will be nice you can add your name to F-15 display name, like cap. Alf.Snake

Good question this is explained by the "Custard Layer theory" Which is the empirical proof that the Air gets thicker as altitude increases ... slightly controversial concept but pretty simple. (Note this theory predates Global Warming theory)

 

Take your oblate spheroid (Planet earth) and wrap it with an atmosphere (The custard layer)

then rotate the oblate spheroid around its axis ... what happens to the custard layer ... it gets thrown off ...as does the atmosphere.

 

Nonsense you say .... but lets look at the evidence.

Why is it that (if you accept the theory) that slow aeroplanes that fly in the lower reaches of the custard layer have propellers ? simple the air is so thin they actually need fans to induce air flow. Helicopters who indulge in super thin air "nap of the earth" type flying have the biggest propellers of all.

 

As you get higher the air gets thicker so thick in fact that propellers can no longer turn so then we bring in jet propulsion which allows thick air to be accelerated through a tube to produce thrust. then of course you get into space were its so thick you cant even get the air down a tube so must resort to non air breathing engines like rockets.

 

Take also the pilots those who fly in the lower thin portions of the custard layer can breath quite easily unassisted. however as you get higher the air is so thick then masks and ultimately full pressure suits are required ... least the high altitude aviator drowns in the thicker higher level air

 

Further convincing proof of the theory is the colour of the sky. in the lower thin levels is a lovely cyan sky blue ... however as you climb the sky gets darker until ultimately in space where its really thick its black ! ... pretty convincing so far.

 

Now of course there many other empirical proofs but lets get back to your question.

 

"Why does speed decrease with altitude" ... simple in terms of Custard layer theory . Given airspeed is measured by Pitot static systems in the lower or thin portions of the atmosphere the air molecules are free to move and their concentration is obviously less so they can rapidly move through the pitot system. However as altitude increases the air becomes thicker and poor air molecules become congested and constrained by the pitot tubes and can no longer move through it as quickly as at the lower levels and so a lower speed is registered.... all quite simple really. It just takes a little outside the box type thought see the answer.

 

BTW "Custard layer theory" also explains why Chem trails can linger so long after they have been dispensed .... but much of that subject is of course classified.

 

Anyway I hope that brief discussion on "custard layer theory" helps answer your question :)

Ivank you are meant to mention Chem trails on a public forum.

Custard layer theory :lol:

How do RWRs tell the difference between being hard-locked and being fired/launched upon by an enemy?

Radars change modes to guide the missile in and possibly emit a missile data-link signal.

is there a difference between Rpi and Rmax, and if so whats the difference?

Don't quote me on this, because it's been a while since I read up on it but basically:

Rpi: Vmissile=Vlaunch (Or in a tail chase, =Vtarget + 180kts)

Rmax: Some guaranteed minimum g capability (eg 4g) or other condition like running out of guaranteed battery time etc.

Of course, the best part of this is that some research paper probably changes the definition of these every year :D It may all be defined in terms of calculated Pk and other parameters.

do you guys know why certain aircraft are always loaded with the same configuration on certain pylons all the time? like the A-10C always having AIM-9s and TGP on the left and the ECM pod on the right? or the F-16 always having AIM-120s on the wingtips instead of AIM-9s?

I don't know about the A-10 ... for the F-16, using AIM-120s on the wingtips provides better aerodynamics somehow.

The standardization of the target pod location allows all members of the flight to share the same FOV in the pod, so that they can effectively see the same things at the same time when in orbit. The right wing seems to be the standard, for whatever reason. The rocket pod/jammer combination is a similar weight to the TGP/AIM-9 combination on the other wing; the aircraft are typically configured this way for balance from what I understand.

How do you defeat radio guided missiles like the Tunguska and Roland?