Technical Questions in relation to my 'Alternative ADF ORBAT' please

[M.A.D]

OK, after receiving your enlightening feed back, I've done a little further research re the notion of a 'mixed' IR and radar (Aim-9C) guided Sidewinder AAM armament for my Alternative ADF ORBAT Mirage III's, as possibly the lightest, simplist and most cost effective armament arrangement for killing bombers.
During this research into the Aim-9C, I found this:

'Because the Aim-9C relied on signals transmitted by the launch aircraft, and reflected by the target aircraft, the lack of Doppler processing made the Aim-9C's performance poor at low altitude or in a lookdown situation where the Aim-9C would confuse ground clutter for the legitimate signal.'

(Source: Elizabeth Babcock, 2008. Magnificent mavericks : transition of the Naval Ordnance Test Station from rocket station to research, development, test, and evaluation center, 1948-58)

Now this is interesting, because I was strongly favouring the idea/notion of equipping my RAN carrier's with a similar mixed IR and radar-guided Sidewinder AAM armed Vought-Chance V-384! But neither the V-383 (F8U Crusader) nor the V-384 had a Doppler radar fitted.
So as much as its obvious that Mirage IIIO(A) had a Doppler fitted, which I hope elevates the issue and effectiveness of the Aim-9C/Mirage IIIO combination for the RAAF; does the forum think the V-384 (or for that matter, it's larger brethren, the F8U Crusader) could accommodate a Doppler radar to fix the Aim-9C/V-384 short coming issue?

I fully appreciate that the V-383 and even more so the smaller V-384 limited space for such a request.

M.A.D

[elmayerle]

I suspect the biggest concern is the difference in the size of the electronics boxes required and the necessary cabling connecting them (this being well before MIL-STD-1553 databuses).  I don't see any real restriction, though you may need to change out the radar to something suitable.

I can't help but wonder if the need for Doppler processing is on the missile side rather than the aircraft side?  In that case, you might need a longer missile body to fit the added processing capability.

[M.A.D]

I suspect the biggest concern is the difference in the size of the electronics boxes required and the necessary cabling connecting them (this being well before MIL-STD-1553 databuses).  I don't see any real restriction, though you may need to change out the radar to something suitable.

I can't help but wonder if the need for Doppler processing is on the missile side rather than the aircraft side?  In that case, you might need a longer missile body to fit the added processing capability.

Thank you elmayerle, what you point out sounds valid!

M.A.D

[M.A.D]

'....the V-383 & V-384 were designed with with a retractable rocket pack in the belly that stored thirty-two 70 millimeter (2.75 inch) "Mighty Mouse" unguided folding-fin rockets. In production aircraft, this rocket pack would rarely if ever be used and was often sealed shut.'

(Source: http://www.crusader.gaetanmarie.com/articles/goebel/part1.htm)

So does anyone know what, if anything this space assigned to the 'rarely if ever used rocket pack' used for? 
Was this empty rocket pack space utilised for additional fuel or avionics/electronics in later variants of the Crusader?
If not, I'm wondering if a Doppler radar and it's associated avionics could utilise this space? Do you reckon this might work?
Or going to this degree of effort and cost, I'm wonder if it would just be as simple as introducing the Aim-7 Sparrow and it's associated avionics/systems into the V-384 during production? 

M.A.D

[GTX_Admin]

Wow, never heard of this hybrid Aim-9 HAP before Greg  I like the concept, but could you give me a better insight into it's timeframe of R&D please?

This was from 1970 and comprised a Sidewinder with a Sparrow rocket motor.  HAP stands for High Altitude Project and it was supposedly created as a response to the use of high-altitude scouts MiG-25 over Israel.

[GTX_Admin]

I was strongly favouring the idea/notion of equipping my RAN carrier's with a similar mixed IR and radar-guided Sidewinder AAM armed Vought-Chance V-384! But neither the V-383 (F8U Crusader) not the V-384 had a Doppler radar fitted.

Err, I am somewhat confused here since the AIM-9C SARH variant was specifically designed for (and used) on F-8 Crusaders:



Upper missile is an AIM-9C.

It was subsequently withdrawn reportedly because its envelope was too restricted and it wasn't very reliable.

[M.A.D]

I'm sorry Greg, I acknowledge your confusion.
But as far as the Aim-9C was designed for and deployed by the F-8 Crusader, as you have posted:
"It was subsequently withdrawn reportedly because its envelope was too restricted and it wasn't very reliable."

This reliability/restriction issue of the Aim-9C was seemingly due to the confusion of the seeker in relation to ground clutter at lower altitude - which one would assume would be the principle course enemy bombers would take in attacking a carrier battle group.
Hence my question in relation to the installation of a Doppler radar, so as to remedy this problem, and give the RAN V-384 a lookdown - shotdown capability, with the Aim-9C.

M.A.D

[GTX_Admin]

I actually suspect the problem with the radar was not so much about it being 'doppler' or not but rather other problems.  I am still researching this but if you have a read of the section on AIM-9C (also called SARAH) here, you will get a feel for what I am referring.

[GTX_Admin]

which one would assume would be the principle course enemy bombers would take in attacking a carrier battle group.

Depending upon the era you are talking about, you would not necessarily expect this to be the case.  In fact, for much of the 1960s and even into the '70s and beyond, one could just as much expect an attack on CBGs to come from high altitude using stand-off missiles.

Hence my question in relation to the installation of a Doppler radar, so as to remedy this problem, and give the RAN V-384 a lookdown - shotdown capability, with the Aim-9C.

Again, I think this will be dependent upon the era you are talking about.  Honestly, until the introduction of the F-15 I doubt you will find any weapon systems with an effective look down - shoot down capability, and even then I have read stories of the F-15's radar having issues.

[M.A.D]

I actually suspect the problem with the radar was not so much about it being 'doppler' or not but rather other problems.  I am still researching this but if you have a read of the section on AIM-9C (also called SARAH) here, you will get a feel for what I am referring.

Interested in your Aim-9C research mate!
It Murphy's Law,  that the link you've given finishes where it's does.  Might be worth my while following this book up.
Thanks for your input Greg!

M.A.D

[M.A.D]

which one would assume would be the principle course enemy bombers would take in attacking a carrier battle group.

Depending upon the era you are talking about, you would not necessarily expect this to be the case.  In fact, for much of the 1960s and even into the '70s and beyond, one could just as much expect an attack on CBGs to come from high altitude using stand-off missiles.

Hence my question in relation to the installation of a Doppler radar, so as to remedy this problem, and give the RAN V-384 a lookdown - shotdown capability, with the Aim-9C.

Again, I think this will be dependent upon the era you are talking about.  Honestly, until the introduction of the F-15 I doubt you will find any weapon systems with an effective look down - shoot down capability, and even then I have read stories of the F-15's radar having issues.

Some good and valid points Greg! 
All the more important that my Majestic class carrier's (with the help of Donny / dy031101)
have the best opportunity of survival in a hostile environment!!

M. A. D

[GTX_Admin]

Might be worth my while following this book up.

Ok, I did some more research (including purchasing the book in question and reading the section on AIM-9C right away).  Quite interesting in that it speaks highly of the AIM-9C development.  There is no real talk of poor performance in regard to the radar - in fact, the author (and the guys at the time) speak quite highly of the F8U-2NE Crusader's Magnavox AN/APQ-94 whereas they were far from impressed with the Westinghouse AN/APQ-72 in the F-4Bs at the same time.  The basic summation was that the F-8/APQ-94/AIM-9C combination worked quite well (for its day) and that the only reason the AIM-9C was eventually withdrawn was that the F-8 was also being withdrawn.  They did say that pilots were at first sceptical of the AIM-9C's SARH guidance and the fact that they would be able to use it as an all aspect weapon (i.e. no longer be forced to only fire in a tail chase scenario, which was typical of the IR guided AIM-9B/D) but that this was overcome once they saw it operate.  I wonder if this doubt is still part of the lingering misinformation about the weapon?  I also suspect that the limited production numbers were still tied to my previous comments about minimal use of such weapons due to engagement parameters, including the fact that the IR guided versions were fire&forget whereas the SARH version required the pilot to keep pointing towards the target?

Either way, I think the AIM-9C is still a useful weapon (for its day) and there is certainly no mention of doppler radar, or lack thereof, issues.  That said, the system was certainly not 'look down-shoot down).  In fact, no-one had this capability operationally until the F-4J/Westinghouse AN/AWG-10 combination in the late 1960's/early 1970's ( I was wrong with the F-15 comment earlier).  Therefore, I wouldn't really hold this against the F-8/AIM-9C.

That said, giving the Mirage with its Cyrano II radar the AIM-9C may have issues.  For one, there would need to be some compatibility matching  though this is not impossible to overcome - after all, the Cyrano was able to guide R.530s which were also used on Aéronavale F-8E(FN)s.  One issue might be the dish diameter (this was something mentioned in the Sidewinder book) with the Cyrano II having a dish of 36cm whereas the AN/APQ-94 was of 53.3cm (21").  One option might be to try to give the Mirage III the AN/APQ-94 and possibly result in a 'big nose' Mirage (the "Cyrano de Bergerac" version?). 

[GTX_Admin]

So as much as its obvious that Mirage IIIO(A) had a Doppler fitted, which I hope elevates the issue and effectiveness of the Aim-9C/Mirage IIIO combination for the RAAF

The Marconi continuous-wave doppler radar fitted to the RAAF Mirage IIIs was only a navigation radar (in addition to the normal Thompson-CSF Cyrano II radar in the nose).  It had no weapon related capability what-so-ever.

[M.A.D]

Wow, thanks Greg,  some good info there mate, and it looks like you scored a good book - it's so difficult to find anything significant on the Aim-9C.

M. A. D

[M.A.D]

G'day all!

I'm up to doing the 1970's time frame of my 'Alternative ADF ORBAT' Army component - prodomantly the replacement of the Centurion MBT and support vehicles. In terms of 'real-world' history the Australian Army / government conducted the following:

"During the period March to May 1971, RAAC officers visited the United States of America, Canada, the United Kingdom, France, Belgium and the Federal Republic of Germany to review developments in armoured vehicles. Main Battle Tanks (MBTs) that were reviewed by the group included M60A1 (USA), Chieftain and Vickers (UK), AMX 30 (France) and Leopard (Federal Republic of Germany). The review of these armoured vehicles was the first step in the programme to investigate the replacement of the Centurion as the Australian Army's Main Battle Tank."

Now in truth and reality I have no problems with (and support) the 'real-world' selection of the Leopard 1A3, as I've worked with the Leopard 1AS over many years in my time in the Australian Army. But I'd like to find more information if I could, with your support of knowledge and recourse please. Does anyone have any further/more informative information on the reviews/eveluations of the likes of the Chieftain, Vickers and AMX-30 by the Australian delegation of the time, and if possible, if any details of these tanks in say 1971 $$$ terms (Jane's Defence etc...)??

I don't want to give too much away, but I have a scenario in mind, which could/might derive another winning design - other than the M60/Leopard 1 contenders 


M.A.D

[M.A.D]

G'day all

I've got a couple of questions for the forum please:

1/ I'm looking for a picture/drawing that clearly shows a scaled-size comparison of Grumman E-1 Tracer and Grumman E-2 Hawkeye AEW aircraft?

2/ I have a technical question in relation to the Grumman AF-3F Guardian and the fitting of its externally-mounted retractable ASQ-8 Magnetic Anomaly Detector (MAD) boom, which was "scabbed" onto the starboard (right) side of it's fuselage, to make it a more effective submarine killer.

In an article I've read by Tommy H. Thomason (http://tailspintopics.blogspot.com/2015/02/grumman-af-guardian-notes.html?m=1)
Tommy H. Thomason states that due to the added weight and space required (and I dare say drag) of fitting the MAD system and the large APS-31B surface-search radar under the right wing "required removal of some equipment and stores capability, " as well as a reduction of onboard fuel, which intern reduced the AF-3S's endurance from six to five hours.

Does anyone know how how big was the actual technical/systems/componentry of this ASQ-8 within the aircraft itself?
Also did the 'unseen' internal technical/systems - 'black boxes' of MAD get smaller/more compact and lighter by the 1960's?



M.A.D


 

[jcf]

Quick n' dirty sideview comparison, the E-2 is a bit over 12' longer.
I've lined up the wing leading edges.

[M.A.D]

Quick n' dirty sideview comparison, the E-2 is a bit over 12' longer.
I've lined up the wing leading edges.

Thank you jcf for your kind assistance and in put. 👍


M.A.D