| Author |
Message |
|
Neno
|
 Posted: Jan 20, 2007 - 09:13 AM
|
 
|
|
Active Member
Joined: Sep 29, 2006
Posts: 128
Status: Offline
|
Recently I was thinking about how important is to hide the first stage of an engine compressor for stealthiness purposes. Remember the famous grid on F117 and the "S" lead of F23 and F22 to prevent the enormous echo doppler caused by moving parts?..
Now, take a look to F117's, B2's and YF23 nozzles and compare them whit the relatively conventional ones of F22: Last stage of turbine is still visible..
Well, the question is: then when the raptor is observed from behind (when it's backing home) how stealth is?... |
|
|
|
|
|
 |
|
Sponsor
|
 Posted: Nov 18, 2008 - 5:10 PM
|
|
|
F-16.net Sponsor
|
|
|
|
|
|
Raptor_One
|
|
Posted: Jan 20, 2007 - 08:21 AM
|
|
|
Elite 1K
Joined: Aug 19, 2004
Posts: 1092
|
| The 2D thrust vectoring nozzles have a stealthy design which reflect some of the radar energy. The nozzles also conceal a good portion of the aft turbine section when in cruise/supercruise. Less so in AB. It's a design compromise. The F-22 will not be as stealthy from the rear as from the front. |
|
|
|
|
|
|
|
loflyn
|
|
Posted: Jan 20, 2007 - 05:30 PM
|
|
|
Enthusiast
Joined: Oct 12, 2005
Posts: 21
Status: Offline
|
| Take a look at Jay Miller's Aerofax: Lockheed Martin F/A-22 Raptor, pages 107 and 127. There's a 'feature' in the afterburner that takes care of this. I'll just say that the turbine is NOT directly visible from behind. |
|
|
|
|
|
|
|
apags27
|
|
Posted: Jan 20, 2007 - 05:43 PM
|
|
|
Active Member
Joined: May 02, 2005
Posts: 152
Status: Offline
|
| Luckily not to many things would be able to catch up to the Raptor. |
|
|
|
|
|
|
|
Lightndattic
|
|
Posted: Jan 20, 2007 - 08:27 PM
|
|
|
Active Member
Joined: Oct 06, 2005
Posts: 218
Status: Offline
|
|
apags27 wrote:
Luckily not to many things would be able to catch up to the Raptor.
Exactly. Anything not already destroyed when the Raptor is ingressing would be at a serious disadvantage trying to chase down a supercruising raptor on it's way home. The constant high speed shrinks the engagement envelope. |
|
|
|
|
|
|
|
sferrin
|
|
Posted: Jan 22, 2007 - 07:47 PM
|
|
|
Elite 1K
Joined: Jul 22, 2005
Posts: 1088
Status: Offline
|
| Radar blocker in the tail pipe. Check the radar blockers in the Super Hornets intakes. Same concept. |
|
|
|
|
|
|
|
Neno
|
|
Posted: Jan 23, 2007 - 08:25 AM
|
|
|
Active Member
Joined: Sep 29, 2006
Posts: 128
Status: Offline
|
| Some link (of a picture of this).. ? |
|
|
|
|
|
|
|
checksixx
|
|
Posted: Jan 25, 2007 - 02:23 AM
|
|
|
Elite 1K
Joined: Jul 20, 2005
Posts: 1035
Status: Offline
|
| You won't get a pic Neno... it doesn't exist... |
|
|
|
|
|
|
|
Lightndattic
|
|
Posted: Jan 25, 2007 - 03:21 PM
|
|
|
Active Member
Joined: Oct 06, 2005
Posts: 218
Status: Offline
|
There's something in there the USAF doesn't want us to see:
 F-22A aircraft assigned to the 27th Fighter Squadron at Langley Air Force Base, Va.
<a href="http://www.af.mil/shared/media/photodb/photos/060131-F-4109K-027.jpg">Hi -res version</a> |
|
|
|
|
|
|
|
MechFromHell
|
|
Posted: Jan 25, 2007 - 03:41 PM
|
|
|
Senior member
Joined: Sep 22, 2005
Posts: 306
Status: Offline
|
Isn't it the point to not leave anyone alive to be able to view it from behind? LoL  |
_________________
Crew Chief
Mountain Home AFB 2000-2005 ~ Acft 91-0370
Sheppard AFB 2005- NOW
www.myspace.com/mechfromhell
|
|
|
|
|
|
idesof
|
|
Posted: Jan 25, 2007 - 08:59 PM
|
|
|
Forum Veteran
Joined: May 29, 2006
Posts: 640
Status: Offline
|
|
checksixx wrote:
You won't get a pic Neno... it doesn't exist...
Not true. Jay Miller's F-22 book is loaded with pictures of the Raptor's a$$ in its last pages with a clear view inside its engines. It certainly does not look like any engine I've ever seen from that perspective... |
|
|
|
|
|
|
|
sferrin
|
|
Posted: Jan 26, 2007 - 02:58 AM
|
|
|
Elite 1K
Joined: Jul 22, 2005
Posts: 1088
Status: Offline
|
|
idesof wrote:
checksixx wrote:
You won't get a pic Neno... it doesn't exist...
Not true. Jay Miller's F-22 book is loaded with pictures of the Raptor's a$$ in its last pages with a clear view inside its engines. It certainly does not look like any engine I've ever seen from that perspective...
It's in there. I remember reading about it in AvWeek a couple years back. I've got the Jay Miller book too. It's definitely got the blockers in there. Unless "checksixx" actually works on them and they've decided to remove them all (which makes no sense). On the other hand it could be a "fit in time of war" item or something I suppose.
"Lockheed has been working diligently with Pratt & Whitney to reduce the infrared, acoustic, and radar signatures of the JSF engine. In addition, knowledge acquired in the F-22 program undoubtedly will be integrated into the JSF. Specifically, experts speculate that the F-22 engine exhaust radar blocker will be applied to the JSF as well. Engineers have toiled to develop a device to block the radar return of the exhaust cavity and simultaneously survive the extreme temperatures (Fulghum “Stealth is Still…” 46)"
Fulghum is a writer for AvWeek
http://web.ics.purdue.edu/~gpollock/The ... rcraft.htm |
|
|
|
|
|
|
|
checksixx
|
|
Posted: Jan 26, 2007 - 07:21 PM
|
|
|
Elite 1K
Joined: Jul 20, 2005
Posts: 1035
Status: Offline
|
|
sferrin wrote:
Not true. Jay Miller's F-22 book is loaded with pictures of the Raptor's a$$ in its last pages with a clear view inside its engines. It certainly does not look like any engine I've ever seen from that perspective...
It's in there. I remember reading about it in AvWeek a couple years back. I've got the Jay Miller book too. It's definitely got the blockers in there. Unless "checksixx" actually works on them and they've decided to remove them all (which makes no sense). On the other hand it could be a "fit in time of war" item or something I suppose.
I worked with the Raptor's and I can't believe your comments. In your own pic you decided to link to its very clear what those are. I can confirm that your super secret RADAR blockers are in fact 'tail-pipe plugs' with remove before flight streamers. They put those in...kind of like intake covers...to keep out FOD. You may not want to believe everything you read... |
|
|
|
|
|
|
|
sferrin
|
|
Posted: Jan 26, 2007 - 07:45 PM
|
|
|
Elite 1K
Joined: Jul 22, 2005
Posts: 1088
Status: Offline
|
|
checksixx wrote:
I worked with the Raptor's and I can't believe your comments. In your own pic you decided to link to its very clear what those are. I can confirm that your super secret RADAR blockers are in fact 'tail-pipe plugs' with remove before flight streamers. They put those in...kind of like intake covers...to keep out FOD. You may not want to believe everything you read...
LOL. Well those definitely aren't what I'M talking about. Go take a look at a picture of the radar blocker in the inlet of the Super Hornet. They look somewhat like that. And I definitely know what the rear end of an afterburning turbofan looks like WITHOUT them. |
|
|
|
|
|
|
|
checksixx
|
|
Posted: Jan 26, 2007 - 08:23 PM
|
|
|
Elite 1K
Joined: Jul 20, 2005
Posts: 1035
Status: Offline
|
Well I've looked into the tailpipe's of Raptor many times and I can tell you that I've never seen anything other than the augmenter section rear end...The fact that you posted the pic which clearly shows an ordinary everyday item and then changed your tune..."LOL. Well those definitely aren't what I'M talking about."....makes me wonder just what you are talking about. For those of us that actually know what the tailpipe in a Raptor looks like, post a pic of what your describing for us...
Check |
|
|
|
|
|
|
|
|
Search
Register
Log in to check your private messages
Forum Guidelines
