What are the various Homing Technologies for PGMs ? Both current and upcoming

I could think of 5 different types of homing technologies for modern day Precision Guided Munitions (PGMs) :


1.Infrared Homing
2.Laser Homing
3.Radar
4.Satellite Based Navigation (GLONASS, GPS...)
5.Precision Inertial Navigation Systems


Am I missing out any other homing technology ?

There are groups but also subgroups as technology expands and the range of targets is accounted for.

For instance IR homing... an old AA-2 missile can detect and home in on a hot target like an aircraft engine. Not much use for anything that does not have a very hot part. But more sophisticated IIR or imaging IR can see the target in an IR spectrum and could be used against a range of different target types.

Laser homing includes the traditional laser beam pointing at the target and weapon launch to home in on the reflection, but there is also laser beam riding, which is simpler and cheaper and much harder to deal with.

Radar, there is ARH, and SARH.

Satellite based normally include INS...

But there is optical, which is similar to IR, like an ATGM like Milan where the crosshairs in the launcher are kept on the target and the guidance system in the launcher commands the missile to fly down that line of sight to hit the target... the obvious benefit there is that it can be used against any target at all, from a tank or IFV, to a window in a building or a heap of sticks or rocks.

The obvious would be command guidance, often using other methods to find and track the target but keeping the missile cheap and simple by removing all guidance from it and putting it in the launcher/controller.

There is also sound (for naval weapons) and wave detection for wake homing... and during WWII there were a few sniffer systems that detected diesel engines from subs or ships as used from aircraft, but added to that there is also magnetic detection used in depth charges and land mines for use against subs and tanks respectively.

There are now lasers mounted on ships . As weapons against incoming missiles or ucav . Can this laser be used as guidance ? Like beam riding , but seeker in nose , to hit laser itself . The sensor must wear sun block two thousand ! I thought that heat generated on skin of craft , could be used to guide . A zig zag motion to keep everything cool . Evaporative under skin cooling . Or ablative materials . Like sidewinder motion .

Laser dazzlers are used to defeat laser sensors or optical sensors in incoming threats... imagine using your eyes at night for navigation and then the bright flash of a camera... but instead of flashing on and off it stays on and is so bright you can't see anything... you normally look away but even if you didn't and kept looking all you see is an enormously bright light that overwhelms your eyes...

The point is that a missile coming in to attack a ships and you use the laser dazzler... if it keeps coming you stop using it and try something else.

Previously the Soviets planned to include passive anti radiation (anti radar) missiles amongst the second wave of anti ship missiles they launched at a US carrier group because the first missile attack will result in all the ships turning their radar on to see incoming threats so the second wave of missiles would try to get locks on standard radars used by US ships, so it is not a crazy idea, but I suspect it probably would not work.

Especially as you mention if the laser is powerful enough to destroy the laser sensor in your missile... protecting it from the lasers energy would make it unable to see the laser so it might as well not have a laser sensor there...

Ok, so Satellite based includes INS as well ? I thought INS like GLONASS and GPS uses a computer, motion sensors (accelerometers) and rotation sensors (gyroscopes) to continuously calculate by dead reckoning the position ?

Most weapons that can't see their target at launch use INS or strapdown navigation system or autopilot to fly the in the direction of the target area or target location where the terminal guidance can scan for and find the target and get a proper lock.

ARH AAMs use this, most IIR missiles etc etc.

A cruise missile will use INS... these days a ring laser gyro that detects physical movement of the gyro to keep account of the current location of the missile.

In many ways it is the same as a pilot would visually navigate an aircraft... with a map and a stopwatch... you know where you start from and you fly in a particular direction at a specific speed... you aim for significant land features like a road or rail crossing or mountain top or lake or river so as you fly along you can get new fixes on your position on the map to make your location of yourself more accurate.

With a cruise missile you could be flying over flat open featureless terrain... say open sea water and then you fly over a beach and to your left is a river that meets the sea and there is a small town there... in its digital map of its flight path to its target it finds that river with the small town and it is 10km to the west of its proper flight path so it turns slightly to get back on course... because along its course will be other significant features it can use to pinpoint is real location.

If GPS is not being jammed or has not been reset 200km one way or the other by the US military... or just turned off like they did in the Georgian conflict in 2008 then its signal can be checked to test the current location too for periodic locational fixes...


But even a Granit will use INS to get to a location near its intended target where it will start scanning with its radar to find and get a lock on its target... otherwise it would need to use its radar all the way to find things and work out where it is which would give the target plenty of warning it was under attack.

A ring laser gyro has a very long fibre optic cable wrapped around it and it detects movement based on the laser signal sent along the fibre optic cable... it is normally sensitive to detect the earths rotation when sitting on a coffee table in a house...

Also are there any upcoming homing technologies that are being developed in Russia or maybe even in EU & US?

Merging existing technology seems to be a fad... the latest model AS-11 ARM has two optical ports for IR sensors... which makes sense... big powerful radars generate a lot of heat and remain hot even after they are turned off...

In 1996 the Russians introduced sensor fused submunitions with MMW radar and IR sensors... basically a self forging fragment... which is a flat disk of metal with a powerful explosive charge pressed against it... when the charge explodes it rapidly accelerates the disk down at such enormous velocity it crushes it and forms it into a sort of shuttlecock shape that can penetrate the top armour of tanks... both it and the sensors are angled outwards so at a good height it deploys a parachute and it spins as it falls so the radar and IR sensor scan the ground in a circle as it falls as it gets closer to the ground the circle gets smaller and smaller so any tank in that area will eventually be detected by the MMW radar sensor... if the IR sensor detects a running engine... boom... the penetrator fires at attacks the top of the tank.... if it detects a burning tank it continues to fall. If it detects no tank it flips over and points upwards and acts like a mine.

The original model didn't have an IR sensor so the munitions might all hammer the same tank when the radar detects them.

If there was a sure fire route to genius then I am sure it would have been found simply by studying genius's and their up bringing.

I suspect the actual mixture depends on the ingredients... one mans childhood trauma that made him a man and sent him down a path to future success could break another person and create a mad man, or worse.

There are always people with agendas who pop up and claim this or that, but in the long run we really just don't know and probably can't know because it is so complex and we are still relatively stupid.

IQ results show we are getting smarter, they say, but it just might be that we are getting better at IQ tests...

Back onto topic however I would mention guidance technologies are often combined... for instance a long range air to air missile with active radar homing rarely can be fitted with its own radar powerful enough to detect an enemy target aircraft at its max effective range.

For instance the current model R-77 can engage targets at up to 110km, but of course it could not detect an aircraft at that distance, so it uses inertial guidance to get it near the target where it turns on its terminal guidance in the form of a small active radar to find the target itself, get a lock and then home in to hit it.

That means for an engagement you can use pretty much any form of detection and tracking to determine a loose intercept point and then fire the missile. The missile will travel to that intercept point radar silent... if.... on its way the target makes a significant turn or climb or speeds up or slows down and wont be in view when the missile gets there the new target track is calculated and new interception coordinates are sent to the missile which changes course to a new intercept course... when it reaches a point where the target should be right in front of it but a few kms away it turns on its own radar... detects and locks the target and then homes in on that target to hit it.

Inertial guidance is often used that way... to control the weapon over a distance to get it to a position where it can use more precise guidance to find and hit the target... anti ship missiles, cruise missiles etc etc.

A very long range cruise missile could use updates along its flight path, like a fork in a road or river to determine if it is in the right place or not and update its current position to improve the accuracy of its inertial nav system... pilots do the same when flying cross country... they can look ahead on their flight path on their map and find a major feature like a mountain top or road junction or a bridge over a river and they can check the position they are supposed to be compared with it... for instance if they look ahead and see a bridge to their right at 15 degrees but their flight path should take them over the bridge they can adjust their course and fly over the bridge to get back on course...  Over time INS gets less accurate or the error gets bigger... the more checks and reference points you put in the more accurate you can make your navigation... after flying 5,000km if you look ahead and see a fork in the road you are supposed to be flying over you can adjust your flight path so you fly over it like you were supposed to... all previous flight errors are eliminated and you are basically back on course so you have a CEP of 1, but once past it your CEP will grow again till the next fix.

You might get to your target and it is not where it was supposed to be so the terminal guidance should recognise that and steer the missile into the actual target not where it was supposed to be...

The key is a great idea and a good business plan... take that to the military or financial backers and get them to invest in the project.

Go to places like that Skolkovo that are idea hives that are supposed to direct investment to new ideas or just good ideas to get them going.

Sadly sometimes good ideas are ruthlessly pinched/stolen... or the person you show is too stupid or too narrow minded to see a good idea... or worse they take the idea and change it to make it a failure.

Designing homing technologies for weapons is expensive and very high tech and very technical... personally I would think the easiest area to get in to would be UAVs and you could start by building model aircraft and fly them using remotes... learn the designs... don't just copy the boring glider shape... buy the materials and start designing your own. Start out with conventional designs and feel their balance and how they fly and then experiment with some designs of your own... once you have a feel for the sport find a company that makes UAVs and ask if you can help out... and see what you can learn... talk to the designers and the builders... don't be afraid to make suggestions but also don't be afraid they will tell you your suggestions are silly and wont work.... don't get shitty about it, but do ask why, and if they can tell you actual reasons why you have just learned something new... add that to what you know it will make your designs better. If they just say that they are silly because no one does it that way but can't tell you why... perhaps you should suggest they allow you to use their resources to try it to see if it works.

It might turn out to be a fairy tale and all their new UAVS are from then on based on your revolutionary design, or it might be terrible... but if you don't try you wont know and neither will they.

Never be afraid of failure, just make sure you learn the correct lessons from the failure and move on.

Don't stop at the first hurdle either... make sure it really is a failure before you stop.

Look at the experience with Bulava... they give the job to a company that has never made naval missiles and the first few launches work fine but then they have lots of failures for different little things. It would have been easy to stop it there, but the missile itself was a good design, it was just problems with parts and assembly, and new design issues... now that they are sorted they have a world class accurate long range missile, but they needed to keep a sensible head and look into why it failed each time to work out what the real problem actually was and then deal with it, rather than tantrums and firing people at random like some members here would demand.

Apparently, the next big thing for PGM is a technology called Automatic target recognition (ATR).

For quite some time there have been video processing systems that can analyse video footage and detect moving things and put a box around them... you have probably seen video footage on youtube showing the view from a thermal imager that automatically puts target boxes around objects moving... like a night view from a police helicopter that sees a man running in the dark... the man glows because of his body heat and as he moves a box appears around him and follows his movements.

You have probably seen the same for vehicles and aircraft... these systems basically isolate a group of pixels that are distinct from the background and seem to move together as one object.

The auto tracking systems in tanks and air defence systems like TOR and Pantsir and indeed Kornet and Tunguska all do the same thing.

What they are talking about here however is the next step... without a person doing it, examining or processing the image of the target and comparing it with 3D models of enemy forces and friendly forces and determining what the actual target is.

If the target is an M1 Abrams tank then you can take a video or thermal or MMW radar image of the target and then compare it with a video or thermal or MMW radar 3D model of all sorts of tanks... the computer can check different view angles of the target and determine if what it is seeing is an Abrams tank or something else.

A while back on youtube there was a video about a Russian testing centre and they had models of all sorts of different things... scale models of F-117s, and missiles and both friendly and foreign weapons and systems that were strung up by cables with all sorts of radar and thermal and optical sensors... the objects spun around and imaged/scanned from all different angles...

Once you have a 3D model in video and radar (in multiple different frequencies) and thermal ranges, then you have a basis for comparison.

The face recognition software police now use to find criminals works in a similar way... computers are very quick when it comes to comparing things.

One of the missiles the Russians have been working on for all their services is the 9M100 small IIR guided missile.

Now note it is an imaging infrared missile so it does not just see hot spots like old missiles, it creates an image like a thermal imager.

Now the problem with an air to air missile like R-73 on a stealth fighter is that while it is an excellent and very capable missile... it needs a target lock before it can be launched so from inside a weapon bay it can't see the target... to use it you would need to open the weapon bay and have the missile extend out on an arm that pushes it out of the aircraft bay so it can see the target aircraft the pilot wants to shoot down... then it can be launched with a lock and forgotten.

Fire it without a lock and it wont hit anything or could lock on the next hot thing it sees... not safe.

The 9M100 is an imaging IR missile so it sees aircraft as aircraft and rocks on the ground as rocks on the ground heated by sunlight or whatever.

The idea of the 9M100 is that you use your IRST and radar and helmet mounted sight to look for an enemy aircraft... when you spot it the IRST image can be uploaded to the missile, but also its location in relation to your aircraft... you fire the missile that has not physically seen the target yet and it flys in the direction it has been told the target is located. Now the impressive stuff happens... unlike an active radar homing missile like R-77 an IIR seeker is totally passive so it can start looking at launch for targets without giving away that it is looking for targets (an active radar homing missile normally does not start scanning for targets until it has flown to its intercept point otherwise the target will know they are under attack and have more time to evade or escape.)

The IIR missile can start looking at launch and on its way to the target area it might spot several other targets... it can check its database of shapes to determine what they are and if they look anything like what it was launched at...

But lets say there is only an F-22 out there... the Su-57 detected a strong target with its L band radar, but does not use his X band AESA because he does not want to warn the target it is about to be attacked, so he looks with IRST and sees an F-22 like target... so the Su-57 pilot launches an 9M100 that rapidly flys out and detects the F-22, it checks its shape and identifies it as an F-22 and gets a lock and attacks it and shoots it down.

There is a datalink there so the missile could direct its view to the Su-57 pilot who could change targets if needs be... the missile will not send back video of the target area.... it will say it can see an F-22 and a B-2 perhaps, so the pilot might choose to take out the F-22 first as the biggest threat.

One point is that the 9M100 is a very short range missile but its ability to identify its targets and communicate with the operator make it very very valuable for air to air and as a CIWS for ships, or indeed a potential anti missile defence system for land vehicles too.

But imagine this seeker on an R-37M replacement... you are 200km away from an enemy airfield and you fire an IIR seeker equipped R-37M replacement and it rapidly climbs and flys ballistically into enemy air space towards an enemy airfield... as it comes down it sees all sorts of heat signatures from aircraft taking off, orbiting the airfield waiting to land, or sitting beside the runway being armed and it can see them all from a top profile and identify them very rapidly... the Su-57 pilot gets a datalink signal asking do I attack the 5 F-22s, 20 F-35s, or the B-2 just taking off... pick one and then fire some more...

Obviously the AAM in that case is not invulnerable and could be shot down by local SAMs, but I think you can appreciate what sort of use such a sensor offers.

Actually the description of the new missile (probably Hermes) carried by the new Mi-28NM suggests flys to the target in an inertial command guided flight path with a terminal phase sending back video information of the target... it could be using IIR or MMW to scan the vehicles near the target location so the operator can select which target is top priority... with a group of targets it would have its own priority weightings but the operator gets the final say in case other factors come in to it... ie hit the Humvee because Madeline Allbright is in it... or whatever.

BTW this is not actually super new, the British Brimstone missile is supposed to be able to be fired off in a general direction and detect and ID armoured targets on the ground and decide whether to attack them or not...

Could you expand on that please? How do you ascertain that it is a failure and from this point onward no matter what you try, you will not be successful ? Thanks.

Well an example would be gun launched anti tank missiles.

Three countries started work on such things at different times, two failed and one succeeded.

France decided it wanted such capability and developed a missile and a special 142mm gun to fire that missile... they soon realised that the gun was not very effective at anything except launching the missile and they stopped funding it.

The Americans knew better and had better miniaturisation and electronics and they developed a 152mm missile and a 152mm gun to fire that missile.

They put it in service on the Sheridan light airborne tank, and also a model of the M60 MBT, it was sent to several conflict zones and is not recorded as firing even one shot let alone hitting a target.

The problems were similar to the French... a 152mm gun is a huge calibre, so it rules out high velocity ammo, which leaves HE shells... which would be rather powerful but also rather short ranged and bulky so you wont be carrying many.

After a lot of money spent it is accepted as being a failure... they will say the technology was not ready yet.

On paper the missiles performance was impressive, but in practise all the delicate electronics and dust in the field meant it didn't work at all.

The TOW missile was inferior in speed and range, but in all other aspects was head and shoulders superior, and was much cheaper.

Their mistake was that they wanted to create a missile armed super tank... the Soviets actually made the reverse mistake with the IT-1 and IT-2, which were basically T-55/T-62 level tank chassis with strange low turrets armed with AT-3 missiles where the main gun would normally be mounted.

The Soviet attempt to put missiles in tanks was vastly more successful even though the first missiles were not very impressive at all, later models had much better performance and actually resulted in weapons that could effectively be used against helicopters, which is a unique ability for most modern tanks.

The Soviets way of avoiding the failure of the French and the US was to make the new missiles fit the existing tank guns instead of the other way around... the first missiles were less impressive on paper than the US weapon... called Shillelagh or something, but they actually worked.

Their invention was not some super missile tank, it was to extend the range and performance of all their tanks... new and old... with a new type of ammo that could reach out to 4-5km and destroy point targets like armoured vehicles and helicopters. You generally had 4-6 missiles and the rest of your ammo was standard rounds.

It meant even the oldest tank in the fleet could take out enemy armour at extended distances well beyond the range of their old 100mm rifled guns.

They also made missiles for their mortars and towed anti tank guns and their artillery... the 100mm missile came in versions to be fired from the 100mm rifled T-54/55s gun, the rifled 100mm gun on the BMP-3 IFV, the 100mm smoothbore gun of the MT-12 towed anti tank gun, and even the 115mm smoothbore gun of the T-62. There were other missiles developed for the 120mm mortar, the 122mm artillery guns, the 125mm tank guns and towed tank guns, 130mm guns for naval use, 152mm guns, 160mm heavy mortars, 180mm old artillery guns, 203mm artillery guns, 240mm super heavy mortars... now they are working on guided 57mm rounds and you can bet that means guided 76.2mm and 82mm rounds are in development too...

In fact experience in Syria, they have learned that getting special forces deep behind enemy lines is tricky and dangerous so laser target marking is not as useful as it might first appear, but the use of UAVs to mark targets with lasers behind enemy lines has transformed the usefulness of 122mm and 152mm laser guided artillery shells as a cheap accurate one shot way of dealing with problems...

The US also has the Copperhead guided artillery rounds but even there they made things hard for themselves... the manual is huge and describes how the round needs very special care and attention including checking the optical lense in the nose before loading to ensure it works properly.

The soviet equivalent... Krasnopol, has a lense cover that falls off in flight... the Soviet soldier treats the guided round like a standard round of ammunition that is loaded in standard ammo magazines and handled by auto loading mechanisms... and it is cheaper...

Lots of talk about better design in the west, but what I see from most Soviet and Russian weapons I have looked at is that their design is more practical and sensible and cheaper and reliable.

What I am pointing out is that you need to be clear on what you want and how you expect it to be achieved, often the difference between success and failure is being realistic... at the end of the day if the US weapon had actually worked properly its impact on the battlefield would not have been very impressive and might have effected development of the Abrams, which overall was simply a much better vehicle than either the Sheridan or the M60A2.

The 120mm smoothbore gun from west germany was vastly more useful and cheaper and easier to use than the 152mm missile launcher they wanted.

The Soviet attempt was changed by their experience at already trying to make a missile armed super tank and its failure leading to a much more practical and much more sensible focus for development... enhance all their major calibre gun armed weapons on land and at sea with a new type of ammo that extends the range and performance of their entire tank park.

You can even repeat that in other fields... for a long time Russian divers have had special super cavitation rounds that can be used underwater like a super long range spear gun... the latest versions of these rounds are compatible with 5.45mm magazines and weapons so pretty much any 5.45mm weapon could shoot into water, though you would want to test them before actually firing the ammo under water... they have guns specifically designed for that role, but I don't know of all weapons in that calibre could survive firing while underwater without problems with barrel bulges or proper ammo cycling etc.

Actually in a nutshell, they should have realised that there was never any chance of a 152mm calibre gun needed at the time to fire the missile would be an effective dual purpose weapon, so actually right then they should have realised that a disposable launch tube like the one fitted to the TOW missile made more sense and was much cheaper and simpler... and in actual fact the TOW missile itself, while inferior in terms of range and missile speed was otherwise superior and much much cheaper.

A 120mm high pressure gun offers choice... HE rounds, HEAT rounds, APFSDS rounds... all of which are effective on the modern battlefield.

The 152mm gun had HE rounds and HEAT missile rounds and the latter never really worked, so as an anti tank armoured vehicle they would have been better off with a world war II tank destroyer armed with a 90mm gun... its armour was no worse than that fitted to the Sheridan and it would have been more mobile while its gun was much more capable with HE and anti armour rounds...

The important point is that even if it had worked first time it really would not have been a very good vehicle as it was really only useful with guided missiles, something much lighter cheaper vehicles loaded with TOWs could achieve much easier and cheaper.

RTN wrote:
I'm just throwing one or two examples. In my case things turn out exactly the opposite of what I had planned. Not sure why. Some quantum physics stuff  maybe

Happens to everyone. Plans don't survive past the first shot.

If you don't adapt and change them according to new circumstances and information that is. Key is to be flexible and attempt to approach things from new angles.

There are many millionaires who dropped out of high school, that have been bankrupted several times, yet make their money again and again... there are theories regarding this suggesting the academic system teaches people to fear failure too much and treat a failure as a sin, whereas someone who left school is more likely to try something that is risky, which sometimes leads to failure but also sometimes leads to enormous success too.

A failure is something that happens but to describe someone as a failure, what you are saying is that they are not learning from their failures to improve their rate of success.

The American MIC has learned that the best way to make even a shitty programme cancel proof is to put production into states held by senators with the power to say yes or no.

It resulted in the C-17... a very ordinary and very expensive aircraft that kept getting production orders even when the Pentagon stopped asking for them because most of its components were made in poor areas of the US where the senators of those districts were on committees to decide funding.

They applied that to the F-35 with their allies... they sold the concept of a single aircraft design split into three sub variants that could replace all the western worlds 4th gen fighters with a brand new super stealth fighter design only the US can make... they farmed out production and allowed their foreign partners to invest and it became huge, but right now it is a total mess... airframe hours of less than 2,000 hours compared with the 8,000 hours promised, all sorts of software issues and other problems too... not to mention high operating costs that means it is expensive to own as well as expensive to buy so countries like Norway are having trouble keeping their planes operational because they don't have enough ground crew qualified to keep it working, let alone qualified pilots to fly it... it is a clear example of a failure and if they had not already invested 1.5 trillion into its development they might have cancelled it already and just gone with perhaps two separate types... one STOL for land and CATOBAR use, and one different aircraft optimised for STOVL... it would have allowed a much better design for the land based fighter version/carrier model that could have been more like a 5th gen F-16... lean and agile... instead of the stealthy Buccaneer light strike aircraft with self defence AAMs they ended up with...

I actually like the Bucc BTW... it was a very good little strike jet... with a load of nuclear bombs its low level performance was better than the F-16 and it was faster in that role and it could operate from aircraft carriers... but it was no fighter plane.... it was never intended for that role.

Hedge funds are criminal ponsie schemes... I hate such "economics" bullshit with a passion.

The important things about failure are the evaluations afterwards... just like with wars... if you forever ignore the lessons of war and the opportunity new technology provides then you are doomed to continue fighting the previous war and getting your arse kicked by someone who learned better lessons.

The war in Spain and the conflict in Finland taught the soviets the value of proper armour and that race car mobility is not that important, and also that SMGs are a good idea in close in fighting, and also the value of modern fighter planes and snipers etc etc.

The Soviets had already used their experience on the eastern front that mobility would be important and that they had embraced aviation, so they had an enormous tank and aircraft fleet... their problem was they were at the end of their usefulness cycle rather than at the start... T-26 light tanks were no worse than Panzer I and Panzer IIs in terms of armour and armament but it was the important things like roles within the tank that were wrong... a two man crew just doesn't work because more than two jobs need to be done at any one time... their main aircraft... the Polikarpovs were impressive in the early 1930s, but by the early 1940s they were outclassed... they had new products in 1941... the T-34 and KV-1 were world class, but not enough of them and not enough armour penetrating rounds or fully trained and experienced crews. In the air there were Yak-1s and LaGG-3s and MiG-3s that were not the worst aircraft in the world at the time, though they did get much better with the La-5FN and Yak-3 and Yak-9.

Sometimes goals were not realistic, or you were just unlucky... in the case of the US it thinks it is technically superior to all opposition so as long as it controls exports of high tech stuff it will remain the leader... so for instance it will take Russia decades to get an operational hypersonic missile into service, or a cruise missile sized weapon with unlimited range and a nuclear propulsion system... and when these things enter service... they must have stolen the technology from us... we were experimenting with that in the 1950s...

Actually that might be the problem in the US... all their Nazi inventors are dead...

Regarding sales of Su-35... were their goals unreasonable... or did he turn down realistic opportunities... or did he not explore all realistic chances for export sales... when someone further up the pay grade makes promises to the higher ups that something will happen then they need a scapegoat when it doesn't happen.

You see it when new aircraft designs are touted... they will claim there is a world demand for 1,000s of this class aircraft... well take the F-22... I remember when they first talked about it... they wanted 1,500 of them and were pretty much going to replace the F-15 and most of the F-16s with these aircraft, but then it became clear it would not be cheap and there was no more Soviet Union and Russia was in a bad way and the number dropped to about half... about 750 were needed... but that was a bare minimum... and then they started coming up with more realistic prices per aircraft and it was going to be too expensive... how ironic is that... they could have made 1,500 for less than they spent on the F-35 and had a plane that works mostly for rather less money than they have spent.

Finally they ended up with 189 aircraft built... numbers were underestimated... costs mainly, and numbers were overestimated... demand and the number to enter service... failure?

Commanche, that artillery thing they wanted to replace the M109, B-2, B-1B, F-117... enormous amounts of money wasted on things they are hardly likely to get much real value out, but they are not all total failures... Commanche led to new level thermals and radar systems that ended up as upgrades for Apache, the M109 has had upgrades presumably from technology developed for its replacement, the B-2, B-1B,F-117... well they have used them, but really none of them do something a good cruise missile couldn't have done from a B-52...

Key is to be flexible and attempt to approach things from new angles.

Build flexibility into your plans, and don't be afraid to change plans if circumstances change or you realise what you thought was true at the start is wrong.

Changing plans is not a failure, shifting priorities and being flexible can save the project and prevent a delayed programme coming up with a product that is of no use.

It is not stupid to get something working before putting it into full scale production.

Taking a little longer to get the Su-57 right with its new engines and new systems means when you put it into production it is ready to go... you might still find issues or problems later on down the track, but one or two problems is easier to deal with than over 800 problems 100 of which threaten the safety of pilot or ground crew like the F-35. Having made over 300 of them... if they find something really serious wrong and basically have to remake all the ones they have made what sort of confidence will the operators have in that platform... and how much will it cost to recall over 300 x $100 + million dollar aircraft to get fixed because they had to meet deadlines already repeatedly extended multiple times...

Software issues sounds minor but such aircraft rely on computers... if you were a bank and the information you were processing meant peoples lives and incomes were at stake... don't buy an F-35 computer...

For ballistic weapons that often leave the atmosphere then a quick star fix to determine position makes sense, but ground based radar and beacons were used during WWII and could be interfered with these days as easily as with satellite navigation systems.

Decent high accuracy inertial navigation along with optical or radar with digital maps so the weapon or aircraft can compare its actual location with what its location should look like on a digital map... sometimes terrain comparison is often good enough for fixed targets, while moving targets the autopilot just needs to get you into the vicinity of the target area where your radar or EO or other sensor scans for, identifies, and locks on to the target when the weapon gets close.

Currently there is US GPS, Russian GLONASS, European Galleilo, and the Chinese system... Budeo or something... and most modern navigation systems use combinations of these systems to get the most accurate precision, but of course there is the risk they will be giving false information or be turned off.

For a country like Russia then they can use GLONASS or other guidance systems or combinations of systems, for Iran it is more complex.

Modern inertial navigation systems are often very accurate and normally would only require some sort of optical or radar sensor for the last few seconds of flight to ensure the target is hit directly.

For ballistic targets they go up to enormous heights and would have a spectacular view of the target area... a small radar or IIR system could adjust the flight path in the last few seconds of flight to achieve a good level of accuracy to ensure a kill.