Notice: This is the official website of the All Empires History Community (Reg. 10 Feb 2002)

  FAQ FAQ  Forum Search   Register Register  Login Login

Missile Guidance

 Post Reply Post Reply Page  12>
Author
Genghis View Drop Down
Caliph
Caliph
Avatar

Joined: 02-Aug-2004
Location: United States
Online Status: Offline
Posts: 2656
  Quote Genghis Quote  Post ReplyReply Direct Link To This Post Topic: Missile Guidance
    Posted: 27-Apr-2006 at 21:25

I was just reading a very cool book called The Fundamentals of Aircraft Combat and Survivability Analysis and Design from my university library.  Apparently there are four main ways of directing a missile on a collision course with a target aircraft.

1. Pursuit - The missile tries to turn and point itself at the target for the duration of it's flight.  This usually ends up putting the missile behind the aircraft.  There are some big problems with this system.  First, the missile must execute extremely hard turns in the terminal phase of it's flight when it might be just meters away from the target aircraft.  Second, it must be considerably faster than the target aircraft if it is chasing the aircraft.  This usually occurs when the missile is cruising and has neither great speed, and little ability to turn.

2. Lead Angle Computation - The missile computes what angle between it's line-of-sight and the aircraft is needed to collide with the aircraft, and for maneuvering targets, this angle is computed and adjusted as fast as possible.

3. Three Point Guidance - The missile's course and maneuvers are based on trying to force it to rest on the line between the target and the launch aircraft.  This is computed on board the launch aircraft and relayed by wire or radio.  Beam-riding missiles work this way, to the best of my knowledge.

4. Proportional navigation - Based on the fact that if two moving objects maintain a constant line-of-sight angle between them, they are on a collision course.  Essentially the missile tries to keep a constant angle between it's longitudinal axis and the line between itself and the target.  This is the most common system.



Edited by Genghis
Member of IAEA
Back to Top
Genghis View Drop Down
Caliph
Caliph
Avatar

Joined: 02-Aug-2004
Location: United States
Online Status: Offline
Posts: 2656
  Quote Genghis Quote  Post ReplyReply Direct Link To This Post Posted: 29-Apr-2006 at 22:00
I take it no one finds missile guidance as interesting as I do? 
Member of IAEA
Back to Top
babyblue View Drop Down
Chieftain
Chieftain
Avatar

Joined: 06-Aug-2004
Location: Australia
Online Status: Offline
Posts: 1174
  Quote babyblue Quote  Post ReplyReply Direct Link To This Post Posted: 30-Apr-2006 at 03:42
i find the missiles itself more interesting...from the V-1s and V-2s that i'm now building in Hearts of Irons 2 for use against the poms...to the scuds the iraqi's throw at israel, which wasn't much more accurate than the primative V-2s...
Back to Top
Leonidas View Drop Down
Tsar
Tsar
Avatar

Joined: 01-Oct-2005
Location: Australia
Online Status: Offline
Posts: 4613
  Quote Leonidas Quote  Post ReplyReply Direct Link To This Post Posted: 30-Apr-2006 at 09:45
i find it interesting genghis, but i dont know enough to actaully add to it.

 but thanks for the post.
Back to Top
Erdene View Drop Down
Samurai
Samurai
Avatar

Joined: 23-Apr-2006
Online Status: Offline
Posts: 101
  Quote Erdene Quote  Post ReplyReply Direct Link To This Post Posted: 30-Apr-2006 at 11:15
I've seen Behind Enemy Lines....I think that was the name of the film...anywho....when the bad guys fired a Russian made SAM at the F-15(????) as the missile got closer it fired from the tip first, seemd like a cannon in the tip of the missile....the shot damaged the tail section of the fighter...the missile then blew up the jet.  I can't remember but it was something like that.....so I am just wondering whether these SAMs have 1 or 2 or 3 or even 4 cannon shots in tip of the missile which fires first when the target is in range just to damage it or slow it the target first......Am I making sense???? 
Back to Top
Genghis View Drop Down
Caliph
Caliph
Avatar

Joined: 02-Aug-2004
Location: United States
Online Status: Offline
Posts: 2656
  Quote Genghis Quote  Post ReplyReply Direct Link To This Post Posted: 30-Apr-2006 at 13:12

Originally posted by Erdene

I've seen Behind Enemy Lines....I think that was the name of the film...anywho....when the bad guys fired a Russian made SAM at the F-15(????) as the missile got closer it fired from the tip first, seemd like a cannon in the tip of the missile....the shot damaged the tail section of the fighter...the missile then blew up the jet.  I can't remember but it was something like that.....so I am just wondering whether these SAMs have 1 or 2 or 3 or even 4 cannon shots in tip of the missile which fires first when the target is in range just to damage it or slow it the target first......Am I making sense???? 

I'm pretty sure they don't have bullets in the tip, but most would have fragmentation of some sort coupled with a proximity fuze to make those near misses kills.

Member of IAEA
Back to Top
Bulgarian Soldja View Drop Down
Knight
Knight
Avatar

Joined: 14-Apr-2006
Location: United Kingdom
Online Status: Offline
Posts: 54
  Quote Bulgarian Soldja Quote  Post ReplyReply Direct Link To This Post Posted: 30-Apr-2006 at 21:27

Originally posted by Genghis

I take it no one finds missile guidance as interesting as I do? 

I find it very interesting mate .... i always wondered how in da f**k do they guide em ... and i never actually got down to doing some research on it .... but now u've explained, thx

Back to Top
Bulgarian Soldja View Drop Down
Knight
Knight
Avatar

Joined: 14-Apr-2006
Location: United Kingdom
Online Status: Offline
Posts: 54
  Quote Bulgarian Soldja Quote  Post ReplyReply Direct Link To This Post Posted: 30-Apr-2006 at 21:29

Originally posted by Erdene

I've seen Behind Enemy Lines....I think that was the name of the film...anywho....when the bad guys fired a Russian made SAM at the F-15(????)

Those bad Russian guys were actually Serbian.

Back to Top
Leonidas View Drop Down
Tsar
Tsar
Avatar

Joined: 01-Oct-2005
Location: Australia
Online Status: Offline
Posts: 4613
  Quote Leonidas Quote  Post ReplyReply Direct Link To This Post Posted: 01-May-2006 at 07:09
actaually does sensor fusing which im hearing about quite allot  out of the USA change the way it gets guided? is there a strict rule between the sensor used and the guidance methodolgy?
Back to Top
Lord Ranulf View Drop Down
Consul
Consul
Avatar

Joined: 28-Mar-2006
Location: United States
Online Status: Offline
Posts: 309
  Quote Lord Ranulf Quote  Post ReplyReply Direct Link To This Post Posted: 01-May-2006 at 14:49
for regular updates on US systems.research etc..see: http://www.mda.mil/mdalink/html/mdalink.html
Back to Top
Genghis View Drop Down
Caliph
Caliph
Avatar

Joined: 02-Aug-2004
Location: United States
Online Status: Offline
Posts: 2656
  Quote Genghis Quote  Post ReplyReply Direct Link To This Post Posted: 02-May-2006 at 00:28

Originally posted by Leonidas

actaually does sensor fusing which im hearing about quite allot  out of the USA change the way it gets guided? is there a strict rule between the sensor used and the guidance methodolgy?

The fuze is just what detonates the warhead when it hits or comes close to the traget, and is to a large extent an autonomous subsystem of the missile, which although similar to is not the same as the guidance system.  The guidance system gets the missile to within lethal range of the target, the fuze then detonates it when it comes within lethal range.

The early Sidewinders used optical fuzes, and others used infrared fuzes to detect distance to target.  Sparrows used radio frequency fuzes.  The Soviet R-60/AA-8 Aphid AAM had infrared guidance with a radar proximity fuze.  Most missiles also have a back up contact fuze. 

 



Edited by Genghis
Member of IAEA
Back to Top
Erdene View Drop Down
Samurai
Samurai
Avatar

Joined: 23-Apr-2006
Online Status: Offline
Posts: 101
  Quote Erdene Quote  Post ReplyReply Direct Link To This Post Posted: 02-May-2006 at 14:05
So the missile doesn't actually hit its target...it explodes in a proximity to the target??? The force from the explosion damages and downs the target????
Back to Top
Genghis View Drop Down
Caliph
Caliph
Avatar

Joined: 02-Aug-2004
Location: United States
Online Status: Offline
Posts: 2656
  Quote Genghis Quote  Post ReplyReply Direct Link To This Post Posted: 02-May-2006 at 19:20

Originally posted by Erdene

So the missile doesn't actually hit its target...it explodes in a proximity to the target??? The force from the explosion damages and downs the target????

Correct.  Counting on a direct hit is too risky when you have two objects moving above or close to the speed of sound.  Often the missile will hit the aircraft, but a proximity fuze increases your chances so much more of killing the target.

Member of IAEA
Back to Top
Erdene View Drop Down
Samurai
Samurai
Avatar

Joined: 23-Apr-2006
Online Status: Offline
Posts: 101
  Quote Erdene Quote  Post ReplyReply Direct Link To This Post Posted: 02-May-2006 at 19:54
Btw, I am downloading Behind Enemy Lines I am pretty sure that the missile fired something and whatever it was it had a shot gun effect on the tail section.  
Back to Top
Erdene View Drop Down
Samurai
Samurai
Avatar

Joined: 23-Apr-2006
Online Status: Offline
Posts: 101
  Quote Erdene Quote  Post ReplyReply Direct Link To This Post Posted: 03-May-2006 at 20:48
Which system does stinger and other small shoulder-held missiles use???
Back to Top
Genghis View Drop Down
Caliph
Caliph
Avatar

Joined: 02-Aug-2004
Location: United States
Online Status: Offline
Posts: 2656
  Quote Genghis Quote  Post ReplyReply Direct Link To This Post Posted: 03-May-2006 at 21:20

Originally posted by Erdene

Which system does stinger and other small shoulder-held missiles use???

The FIM-92 Stinger uses passive, all aspect infrared guidance, with an impact fuze.  I believe it doesn't have a proximity fuze due to size and weight limitations.  The Soviet SA-16 Gimlet uses a similar method.  Other systems like the Javelin and Starstreak system use electro-optical guidance.  I like IR guidance more, it's a fire and forget system.

Interestingly, a Swedish missile called the RBS 70 uses a laser beam riding system, with a laser proximity fuze.  Apparently it's missile control is based on what is called the "Linear Quadratic Method" based on the Kalman theory.  This system requires the user to keep the laser on the target till impact, I think that's a great disadvantage.

Member of IAEA
Back to Top
bigtoothbrush View Drop Down
Samurai
Samurai


Joined: 06-May-2006
Location: China
Online Status: Offline
Posts: 121
  Quote bigtoothbrush Quote  Post ReplyReply Direct Link To This Post Posted: 06-May-2006 at 11:47
all passive guidance ones are fire forget, but too easy to be fool unless fit with imaging array or cooperated by other guidance model. while it's impossible to jam semi-active tracked missiles such as RBS 70.
Back to Top
Leonidas View Drop Down
Tsar
Tsar
Avatar

Joined: 01-Oct-2005
Location: Australia
Online Status: Offline
Posts: 4613
  Quote Leonidas Quote  Post ReplyReply Direct Link To This Post Posted: 07-May-2006 at 03:49
Both the stinger's and RBs70 are good mssiles, having different strengths and weaknesses.

Aussies use the RB and a updated deriv called the Bolide. The range and warhead on these things are quite large for its class.
Back to Top
bigtoothbrush View Drop Down
Samurai
Samurai


Joined: 06-May-2006
Location: China
Online Status: Offline
Posts: 121
  Quote bigtoothbrush Quote  Post ReplyReply Direct Link To This Post Posted: 07-May-2006 at 21:35

IR guidance missiles are easy to operate due to their fire forget function. but you can't launch several  IR missiles to deal with several targets at the same time. coz all these missiles will just go for the target with most obvious IR signals.

current most advanced shoulder-held missiles such as chinese QW-4, all use IR imaging seeker. it can't be fool since it's terminal informations are targets imagines. one can simulate signals power and frequency, but can't simulate targets imagines.

Back to Top
Serge L View Drop Down
Baron
Baron
Avatar

Joined: 03-Aug-2004
Location: Italy
Online Status: Offline
Posts: 485
  Quote Serge L Quote  Post ReplyReply Direct Link To This Post Posted: 10-May-2006 at 16:33
Sory, Genghis, could you better specify he diference between system nunber 2 and number 4, since they both are based upon calculation of the angle between missile and target respective trajectories?
Back to Top
 Post Reply Post Reply Page  12>

Forum Jump Forum Permissions View Drop Down

Bulletin Board Software by Web Wiz Forums® version 9.56a [Free Express Edition]
Copyright ©2001-2009 Web Wiz

This page was generated in 0.047 seconds.