Intermittent Sound External Views

Just as the title says, while flying the SU-33 and the F-15C in cockpit the sound never cuts out. However, when the aircraft is viewed using the default F2 and F3 keys at some point the sound will stop. After a random amount of time (say 15 seconds or so) the sound will kick back in. Sometimes you can hear it start and stop for a fraction of a second like its trying to get started again before it "takes hold" and acts normally.

It's a random effect. Interestingly enough, I tried before logging on this morning flying the F-86 around and the F-5E and could not duplicate it in the 15 minutes or so of flying in external modes. I understand the Doppler thing but that should have nothing to do with pacing the aircraft externally using the F2 key. Jumping back into the cockpit and cycling back outside doesn't seem to help - the sound will "catch up" in its own time.

I'm wondering if this is more of a system thing rather than a bug since I don't see a plethora of posts about it.

I was running DCS version 1.5.5 at the time. "Sliders" most all to the right. My rig is running W10 latest software updates 64 bit. My graphics card is the 780ti but the driver I had to go to the 368.81 build due to the latest driver having an issue with BOS. 16GB of DDR5 installed along with the i7-5930k chip running stock 3.5GHz.

Has anybody else experienced these symptoms?

UPDATE: Hmmm...noticed while flying the Nevada DCS 2.xxx that while viewing some aircraft using the F2 key and mouse to pan around the AI aircraft the sound is there if rotated towards the engines, but cuts out completely if the camera is rotated about 90 degrees away from it. Sounds like a bug, at least for this example (which may or may not be related to my issue).

Updated to latest sound drivers, no luck. It's a bug. Cut out occurs whether doing Mach 1 or lower. Doesn't matter.

Yes, I have exactly the same thing. I reported it just after beta release in another thread.

Just to say that the issue is still there after all the patches to date.

Just as the title says, while flying the SU-33 and the F-15C in cockpit the sound never cuts out. However, when the aircraft is viewed using the default F2 and F3 keys at some point the sound will stop. After a random amount of time (say 15 seconds or so) the sound will kick back in. Sometimes you can hear it start and stop for a fraction of a second like its trying to get started again before it "takes hold" and acts normally.

 

It's a random effect. Interestingly enough, I tried before logging on this morning flying the F-86 around and the F-5E and could not duplicate it in the 15 minutes or so of flying in external modes. I understand the Doppler thing but that should have nothing to do with pacing the aircraft externally using the F2 key. Jumping back into the cockpit and cycling back outside doesn't seem to help - the sound will "catch up" in its own time.

 

I'm wondering if this is more of a system thing rather than a bug since I don't see a plethora of posts about it.

 

I was running DCS version 1.5.5 at the time. "Sliders" most all to the right. My rig is running W10 latest software updates 64 bit. My graphics card is the 780ti but the driver I had to go to the 368.81 build due to the latest driver having an issue with BOS. 16GB of DDR5 installed along with the i7-5930k chip running stock 3.5GHz.

 

Has anybody else experienced these symptoms?

 

UPDATE: Hmmm...noticed while flying the Nevada DCS 2.xxx that while viewing some aircraft using the F2 key and mouse to pan around the AI aircraft the sound is there if rotated towards the engines, but cuts out completely if the camera is rotated about 90 degrees away from it. Sounds like a bug, at least for this example (which may or may not be related to my issue).

Just to be sure (don't mind me asking), could it be the effect of Mach-1+ speeds ?

Just to be sure (don't mind me asking), could it be the effect of Mach-1+ speeds ?

This.

Hmm.. have to check the speed when it happens. However, I think the OP said the speed made no difference.

Completely correct guys, it is the effect of Mach 1+ speeds. If I look at F2 view at Mach 1+, it is silent, but if I slow to below Mach 1, then the sound returns!

Good spot.

Well it's normal : from behind the plane you do not hear the sound because it's behind you (camera moving faster that sound) while from the front it's ... well in front of you ;)

Well it's normal : from behind the plane you do not hear the sound because it's behind you (camera moving faster that sound) while from the front it's ... well in front of you ;)

Well, now I’m confused. At Mach 1+, the sound is heard directly behind the engine. Looking at the front or the side of the aircraft, there is no sound.

Different Mach > 1 will have a different angle threshold where engine sound cannot be heard. At exactly Mach no sound will be heard from the forward hemisphere. Beyond Mach the sound will not be heard at an angle which follows the following formula:

1/M = sin(a)

a = InverseCosecant(M)

E.g. at Mach 2 sound can only be heard from angles InverseCosecant(2) or 30° from the tail. Mach 3 19.47°. Mach 4 14.48° and so on.

Different Mach > 1 will have a different angle threshold where engine sound cannot be heard. At exactly Mach no sound will be heard from the forward hemisphere. Beyond Mach the sound will not be heard at an angle which follows the following formula:

 

1/M = sin(a)

a = InverseCosecant(M)

 

E.g. at Mach 2 sound can only be heard from angles InverseCosecant(2) or 30° from the tail. Mach 3 19.47°. Mach 4 14.48° and so on.

I’m afraid InverseCosecants mean nothing to me!

To simplify, are you saying, that if travelling at Mach 1, it is correct that in a F2 view, we hear the engine sound when directly behind the engine and nowhere else?

Well, now I’m confused. At Mach 1+, the sound is heard directly behind the engine. Looking at the front or the side of the aircraft, there is no sound.

That's because I'm an ass and I reversed the effect... It's the opposite : when in front of the a/c you travel faster than the sound could come to you in the opposite direction : it can never reach you → thus no sound in front...

That's because I'm an ass and I reversed the effect... It's the opposite : when in front of the a/c you travel faster than the sound could come to you in the opposite direction : it can never reach you → thus no sound in front...

Phew, I’m glad you cleared that up!

I'm only getting this on certain aircraft, not all of them, whats the equation to work that one out ?

Equation? To work what out?