Author Topic: if im in a p51 in real life can i hear a 109 200 yards behind me?  (Read 1874 times)

Offline Citabria

  • Platinum Member
  • ******
  • Posts: 5149
dosnt doppler effect make this impossible or am i missing somthing?

edit: misunderstanding of term doppler effect.

my point is should we be able to hear anything outside and behind our plane when flying 300mph with a 2000 hp engine next to us making noise while we are wearing a headset that covers our ears to protect them from the noise of the guns and the engine?
« Last Edit: October 26, 2003, 06:16:59 PM by Citabria »
Fester was my in game name until September 2013

Offline oboe

  • Plutonium Member
  • *******
  • Posts: 9805
if im in a p51 in real life can i hear a 109 200 yards behind me?
« Reply #1 on: October 26, 2003, 12:18:34 PM »
I think the accepted answer to your question is "no" - but not because of any Doppler effect.   Because your engine is so loud, you couldn't hear anything outside your own a/c.

If you shut your engine off and opened the canopy, the Doppler effect would raise the pitch of the sound of the 109's engine as it closed the distance.   After it passed you, the pitch of its engine sound would gradually drop due the the Doppler effect.

In AH its just a cool effect, even if its not true to life.

Offline nopoop

  • Gold Member
  • *****
  • Posts: 3210
if im in a p51 in real life can i hear a 109 200 yards behind me?
« Reply #2 on: October 26, 2003, 01:48:40 PM »
I agree, it is a very good effect.

Of course in real life you wouldn't be hearing anything but your engine..

But this ain't real life and it sounds neat
nopoop

It's ALL about the fight..

Offline BUG_EAF322

  • Gold Member
  • *****
  • Posts: 3153
      • http://bug322.startje.com
if im in a p51 in real life can i hear a 109 200 yards behind me?
« Reply #3 on: October 26, 2003, 03:51:51 PM »
u outrun the speed of sound at least to begin with.
(not talkin about the soundbarriere)

Offline beet1e

  • Persona Non Grata
  • Platinum Member
  • ******
  • Posts: 7848
Re: if im in a p51 in real life can i hear a 109 200 yards behind me?
« Reply #4 on: October 26, 2003, 04:11:04 PM »
Quote
Originally posted by Citabria
dosnt doppler effect make this impossible or am i missing somthing?
Cit, you are a tard! But I will answer.

Doppler effect is when you hear a car go past you, and its engine sound pitch drops as it passes you. The wavelength of the sound is being extended because the source of the sound is moving away from you. So no, in your scenario, doppler effect would mean buggery-suet.

Offline jodgi

  • Nickel Member
  • ***
  • Posts: 696
      • http://forum.mercair.net
if im in a p51 in real life can i hear a 109 200 yards behind me?
« Reply #5 on: October 26, 2003, 04:20:45 PM »
If you're blasting away at 400+ mph then it will be very hard to hear anything behind you, even if you're not making any noise yourself.

Planes (anything) reach the sound barrier gradually, so even if warbirds never broke the sound barrier, they flew so fast that they didn't "transmit" sound very far ahead.

Maybe I'll do some maths on this...

Offline wetrat

  • Gold Member
  • *****
  • Posts: 2117
if im in a p51 in real life can i hear a 109 200 yards behind me?
« Reply #6 on: October 26, 2003, 04:21:00 PM »
Beetle, you are in no way, shape or form capable of calling anyone else a tard.
Army of Muppets

Offline jodgi

  • Nickel Member
  • ***
  • Posts: 696
      • http://forum.mercair.net
if im in a p51 in real life can i hear a 109 200 yards behind me?
« Reply #7 on: October 26, 2003, 04:45:42 PM »
LOL. what was I thinking :o

In the p51 and 109 example, the p51 will ofcourse always hear the 109 behind it (theoretically). But since they are travelling at 0.6 mach (400mph) the sound will be a second or 2 old when it reaches the lead p51. But given that they are travelling at the same speed in the same direction, the pitch will be normal. Only if the observer has a different relative speed than the sound transmitter, the doppler effect will come into play and "change" pitch.

My bad on my previous post.

As we say here: I crapped on my leg. :D

Offline zmeg

  • Silver Member
  • ****
  • Posts: 936
if im in a p51 in real life can i hear a 109 200 yards behind me?
« Reply #8 on: October 26, 2003, 04:53:20 PM »
Because you're rapidly moving away from the point where the sound is produced it will be both delayed & deminished, you would be dead before you ever heard a plane diving on you at high rate of closure. Also because ac engine freq. is very low the dopler effect would be very noticable.

Offline jodgi

  • Nickel Member
  • ***
  • Posts: 696
      • http://forum.mercair.net
Forgive me...
« Reply #9 on: October 26, 2003, 05:10:33 PM »
This is so off topic, bear with me...

Does anything happen when I hit 100 posts?

Offline jodgi

  • Nickel Member
  • ***
  • Posts: 696
      • http://forum.mercair.net
if im in a p51 in real life can i hear a 109 200 yards behind me?
« Reply #10 on: October 26, 2003, 05:11:14 PM »
Let's see...

Yes it did.

Ok, I'll behave now.
« Last Edit: October 26, 2003, 05:13:42 PM by jodgi »

Offline MetaTron

  • Silver Member
  • ****
  • Posts: 857
if im in a p51 in real life can i hear a 109 200 yards behind me?
« Reply #11 on: October 26, 2003, 05:43:49 PM »
P51 cockpit sound level makes it impossible to hold a conversation. But I think you worded your question incorrectly.

Doppler effect causes the sound waves to bunch up as a fast moving object approaches and to separate after it passes.

In real life it might appear that you didn't hear anything until just before the plane passed if you were sitting still. When you are both moving you hear a different pitch level because of the relative velocities and it would seem like you can hear the approach from further away.

Offline Citabria

  • Platinum Member
  • ******
  • Posts: 5149
if im in a p51 in real life can i hear a 109 200 yards behind me?
« Reply #12 on: October 26, 2003, 06:02:48 PM »
my point is should we be able to hear anything outside and behind our plane when flying 300mph with a 2000 hp engine next to us making noise while we are wearing a headset that covers our ears to protect them from the noise of the guns and the engine?
Fester was my in game name until September 2013

Offline BUG_EAF322

  • Gold Member
  • *****
  • Posts: 3153
      • http://bug322.startje.com
if im in a p51 in real life can i hear a 109 200 yards behind me?
« Reply #13 on: October 26, 2003, 06:31:10 PM »
No ofcourse not but in real life u could smell a unwashed wable miles away.

Not to mention the combination of the typical leathersmell .

Offline MetaTron

  • Silver Member
  • ****
  • Posts: 857
if im in a p51 in real life can i hear a 109 200 yards behind me?
« Reply #14 on: October 26, 2003, 06:53:42 PM »
A lot of things would be different in real life fester. You couldnt come back after getting killed for one thing.