IFF Question

[KJ_Lesnick]

I'm curious about something (provided it's not classified): Why is it that our IFF systems which were supposed to be able to identify Russian enemy bombers and shoot them down couldn't work in Vietnam?

• The British had IFF systems in WW2
  
• The Mosquito NF variants were able to interrogate german transponders
  

[Mr.Creak]

IFF doesn't "identify bad guys": it tells that the bogey is one of your own.
With large bombers coming in toward the UK it would have been a fair bet that they're not our own - and thus legitimate targets.
In Vietnam the requirement was for a positive identification - a fighter-sized aircraft could have been a US one lost or on some mission that the relevant fighter wasn't aware of/ privy to.

Edit for expansion: a POSITIVE response from an IFF says "I'm on your side".
No response says "I'm not on your side" OR "I am on your side but my IFF isn't working".
So far as I'm aware that's the only possible signals you get: no one transmits "I'm not on your side I'm a bad guy".

[Captain Canada]

Put a W in front of it and now it's a wiff

[tahsin]

America in Vietnam, fully confident that its high tech will prevail. Problems, problems and many Sparrow shoots, nothing works. Finally a perfect day, cleared on the IFF as well and two kills... Turns out out to be 2 F-105s with the IFF issues. F-105 pilots start a rebellion to demand Sidewinders to fire on the Phantoms and the final tally of the time: 45 Sparrows fired, 2 own goals, 43 misses. America is well served by those tiny minority who must be obsessed about things.

[sandiego89]

America in Vietnam, fully confident that its high tech will prevail. Problems, problems and many Sparrow shoots, nothing works. Finally a perfect day, cleared on the IFF as well and two kills... Turns out out to be 2 F-105s with the IFF issues. F-105 pilots start a rebellion to demand Sidewinders to fire on the Phantoms and the final tally of the time: 45 Sparrows fired, 2 own goals, 43 misses. America is well served by those tiny minority who must be obsessed about things.

Source for this "rebellion" please?

I imagine the F-105 crews wanted sidewinders to deal with MiG's, not friendly Phantoms.  Although most of the F-105 MiG kills over Vietnam were with cannon, here is just one source indicating that F-105 pilots believed more kills could have been made had they been equipped with sidewinders earlier and more often.  Page 14

https://books.google.com/books?id=2jJfBAAAQBAJ&pg=PA62&lpg=PA62&dq=f-105+sidewinder+vietnam&source=bl&ots=JR6h08NLOA&sig=ZyXy3pImF4OrzMRycG7H7e0oeok&hl=en&sa=X&ei=ZlShVIrTHsGaNtKrgaAE&ved=0CDkQ6AEwBg#v=onepage&q=f-105%20sidewinder%20vietnam&f=false

Also not sure of the time frame of your Sparrow cite.  There were some 50+ Sparrow kills in the conflict.  Yes numerous misses due to duds, firing outside the envelope etc. and by all accounts had a dissapointing % rate with over 600 fired.  Not sure what you mean by "final tally"?  

I won't bite on the rest of your post.    

[Captain Canada]

Kinda like the time the RCN passed a Sidewinder through a window at FAA base to show it off. Then walked out and mounted it on a Banshee and shot down a Firefly drone.

[KJ_Lesnick]

IFF doesn't "identify bad guys": it tells that the bogey is one of your own.

Well, still: Why didn't it work in Vietnam, but worked in WW2?

[sandiego89]

IFF doesn't "identify bad guys": it tells that the bogey is one of your own.

Well, still: Why didn't it work in Vietnam, but worked in WW2?

Mr. Creak already answered it in post #2.  The rules of engagement during Vietnam often required positive VISUAL identification- via the eyeballs of the pilot.  In other words, it was not a question of IFF "working" in Vietnam, IFF was installed and worked as designed in that conflict, but the rules from higher commmand often required positive visual identification.  So IFF was one of several indicators available (intel, visual, ELINT, surface and air based radar assets, etc) but an IFF indicator by itself was not enough to let loose a missile.  

Different conflicts have different rules of engagement.  War planners and leaders determine the rules based on acceptable risks/rewards.  Some theatres may call for weapons release based on IFF alone, others may not.  Few would today.  Some rules may require more than one indicator before pulling the trigger. In more modern conflicts (like Vietnam) clearance to engage may be required from a ground or air based controller (the rules allow for self defense).  This was not really an option in WWII.   

Some theatres, or specific operations, in WWII may have allowed looser rules, but with the added risk of friendly fire.  Some night fighter operations in Europe come to mind, where other aircraft over certain areas were assumend to be hostile and were frequently engaged, and more than once with tragic friendly fire results.  

If the ROE in Vietnam had allowed beyond visual range engaments based on IFF alone, there would have been many more shots taken, perhaps more early kills, likely many more friendly fire incidents, and likely a significant change in how the NVAF operated.  

IFF was not and is not 100% reliable.          

[KJ_Lesnick]

Mr. Creak already answered it in post #2.

No he didn't, the reason visual ID was required was because the IFF didn't work right...

IFF was not and is not 100% reliable.

Why?

[sandiego89]

Mr. Creak already answered it in post #2.

No he didn't, the reason visual ID was required was because the IFF didn't work right...

IFF was not and is not 100% reliable.

Why?

I disagree. I propose you look at it as recognizing a limitation, and not as much "not working right".   There is a distinct difference, and this known limitation was perhaps more of the reason for instituting more complex ROE, including visual ID.   If you believe that IFF "didn't work right" in meaning that it failed to ID every aircraft 100% all the time and could be absolutely relied upon as the sole source for a trigger pull than perhaps you are technically correct.  The answer is more complicated.  Commanders recognized the limitations of electronic gear such as IFF and instituted rules to prevent friendly fire.  IFF never worked 100% in tests, trials or in combat, and they were not willing to take that risk.  WWII commanders may have been more willing to take that risk.

Commanders recognized that the multitude of friendly aircraft types (and users) in the theatre made IFF unreliable as a sole source determination.  Too many variables to take that risk.    

IFF is not a magical solution.  If we could come up with a magical sytem that could identify every aircraft as friend or foe 100% of the time then yes we would have a great solution, and could do away with all our fancy radars, AWACS, FLIR's, etc.  We are not there yet.    

Fast forward to the Gulf war, F-15 eagles had to have IFF indicators AND clearance from AWACS before engaging.      

IFF is an electronic device.  No electronic device is 100% reliable, especially when fitted in a complex aircraft in a harsh environment where the variances of temperature, humidity, maneuvering, etc all affect electronics.  Electical power can be interupted, fittings come loose, and sometimes IFF just does not work.  

WWII IFF was no where near 100%, but it was gauged good enough for some scenarios.

IFF is also is prone to human factors at multiple levels: was it installed and tested correctly? was the right code entered? is it on?  Is it understood correctly by the human eye/ear/brain?

Should we shoot down an airliner because it is squaking the wrong code?      

[KJ_Lesnick]

I disagree. I propose you look at it as recognizing a limitation, and not as much "not working right".   There is a distinct difference, and this known limitation was perhaps more of the reason for instituting more complex ROE, including visual ID.   If you believe that IFF "didn't work right" in meaning that it failed to ID every aircraft 100% all the time and could be absolutely relied upon as the sole source for a trigger pull than perhaps you are technically correct.

So what was it's reliability about?

WWII commanders may have been more willing to take that risk.

So it was merely a desire to risk shooting down friendly planes by accident?

[sandiego89]

So what was it's reliability about?

WWII commanders may have been more willing to take that risk.

So it was merely a desire to risk shooting down friendly planes by accident?
[/quote]

I do not know what reliabilty % was, but I have read numerous accounts of IFF and radar gear not working properly from WWII through the jet age.  For example pairs of friendly aircraft would take off togther and interogate each other, and get spurious indicators. Not confidence inspiring.

I recently read an excellent account of UK WWII night fighters, and there were numerous cases where a target was detected and surely it was "supposed" to be the enemy because no one else was reported to be there, and sometimes just at the trigger pulling point a friendly  Mosquito or Beaufighter would appear out of the darkness- sometimes from the same squadron.

IFF is not flawless, so commanders do not allow reliance on it.  Helpfull?  Undoubtedly.  Flawless? No.

A few examples of IFF problems:

The 1982 UK Gazelle friendly fire shootdown in the Falklands was partially due to the IFF being turned off to avoid intereference with air defense systems.   

The 1994 F-15 friendly fire of US H-60's in the Iraq no fly zone involved an IFF failure or improper settings/errors, miss-identification visually, and controller and proceedural problems. 

Iraq 2003.  US patriot batteries shot down a UK Tornado and a US F-18.  IFF failure/proceedures suspected as primary cause.

No one wants to shoot down friendly aircraft, and each theatere requires commanders (or politicians) to recognize limitations of equipment and potential risks/gains and promulgate ROE.  In some theatres you have more liberal ROE.   

[kitnut617]

I think you're missing something, during WWII, to get the 'shot', you had to see what you were shooting at, physically no matter what, because usually you had to get within 300-500 yards to do it.  There was none of this 'beyond visual range' stuff then, even the nightfighter pilots had to identify what they were about to shoot at before they shot.  In Vietnam, there was the capability of 'BVR' but as sandiego says, there were rules implemented, mostly because it wasn't classed as a ""war"" was it ?

Another thing, IFF was mainly used during WWII so the 'ground controllers' could tell who was who, not aircraft to aircraft

[rickshaw]

One should also be aware that IFF in WWII is not the same as IFF today.   IFF then was a simple broadcast radio signal which was preset before take off to the code "of the day".   It had to be turned off, once outside of friendly airspace because it could alert the enemy to the presence of your aircraft.   In those days,  to check if IFF was present, a direction antenna was pointed in the right direction and you listened in.

Modern IFF is far more sophisticated and it uses transponders.  An interrogator sends a coded signal to the target and it responds and sends a coded response signal back.   On the modern battlefield, it's primary use is for ground forces to make a positive ID before firing and with the proliferation of MANPADS in the 1980s, it was a very necessary addition to those systems.

This SA-7 Grail crew have an IFF interrogator on one of their helmets:



This Japanese Type 91 Kai MANPADS system has an IFF interrogator aerial on top (its the cage like structure):



The Stinger MANPADS has a similar arrangement:



No system though, is 100% effective which is why in Vietnam the demand was for visual ID of all targets, to prevent escalation of the conflict to potentially involve the PRC if "blind" BVR shots were taken.

Despite what you believe (as indicated on the BeyondSprue website), the US forces did understand about the dangers of escalation.

Now, please, stop asking and re-asking the same questions time after time.  If you don't understand the answers, ask for clarification but please, accept them when it's obvious that is the blasted answer!

[KJ_Lesnick]

sandiego89

I do not know what reliabilty % was, but I have read numerous accounts of IFF and radar gear not working properly from WWII through the jet age.  For example pairs of friendly aircraft would take off togther and interogate each other, and get spurious indicators.

When did this happen (like 1950's, 1960's)


kitnut617

I think you're missing something, during WWII, to get the 'shot', you had to see what you were shooting at, physically no matter what, because usually you had to get within 300-500 yards to do it.  There was none of this 'beyond visual range' stuff then, even the nightfighter pilots had to identify what they were about to shoot at before they shot.

If I recall, there was a case where a C-54 got shot down because it resembled a Fw Condor/Kurier.  If I recall the attack was carried out because of a lack of functioning IFF gear...

In Vietnam, there was the capability of 'BVR' but as sandiego says, there were rules implemented, mostly because it wasn't classed as a ""war"" was it ?

So, the fact that it was a conflict made a difference?