Inertial Navigators in UK

alertken

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Who can flesh this lot out?

1954: Sperry/UK, licence from Sperry/US: intended for (to be) Blue Streak. Bracknell clean room. Abandoned for:
3/57: Elliott licence from Bosch Arma (ATLAS kit). Rochester clean room. B Streak died 13/4/60 but INS work continued for Blue Steel.
1957: Ferranti, licence from Kearfott: intended for (to be) TSR.2. Delivered into Tornado. Edinburgh clean room.
4/58: English Electric licence, Minneapolis-Honeywell. Stevenage clean room. (What project? Did they do Polaris SINS here?)
9/58: S.G.Brown (became DH, HS Group), licence from Bosch Arma (what project?); then:
1961: licence from Bendix (why?).
1961: Rank Cintel, Sydenham, London (became Elliott): licence from GTI (why?).

Litton set up W.German and Italian subsidiaries, on F-104G. Did GM (A.C Spark Plug) do anything over here?
 
Ken,

Fantastic post, thank you very much, I have been looking for information on UK INS procurement/development/licensing for years!

I have had a chance to visit the formerly Litton now NG subsidiary in Italy and was told how for the F-104 project they hired every watchmaker they could find and employed hundreds. MTBF was tens of hours at best but man-hours for production was thousands. A huge facility was constructed and today only a fraction of it is still used though INS are still manufactured there.

I know Sperry Gyroscopes (UK) flew a system designed for manned fighters in November 1954 (were not allowed to show it until 1958). EE were apparently working on their own gyros and platforms both prior to and after the Honeywell license (for miniature integrated gyroscopes) and SG Brown had the manned fighter contract with two gyro master reference units, the Mk 1 and 2 MRGs which were their own design (I believe?) but the Mk3 used the Arma brown floated Gyros- that may have been for helicopters, there was a Brown-Arma gyro compass for use in helicopters and Hovercraft- it was actually used in the Denny D2. Brown also did maritime INS though having been an admiralty holding until 1960. Then there was the Brown Gyrotwin that appeared in 1960 (though claimed to be all British).

Both EE and SG Brown got their license in the same year, 1958, so I have always assumed they were competing for something- Lightning perhaps? Equally, Sperry gyros flew its design in 1954 which was the same year SG Browns system first appeared so I always assumed some sort of competition there- Swift / Hunter / Scimitar possibly? Just a theory for which I have zero evidence.

As for the later versons (SG Brown/Bendix, Rank Cintel/GTI) I have no idea! Could have been speculative given continued avionics developments elsewhere? Elliots ultimately got Jaguar (E.3R- total nav/attack system package was NAVWASS) and Nimrod (E.3 platform). I understood the Tornado/TSR-2 link to be the following: the TSR-2 system was in some way adapted for the Harrier and that system was then further developed (becoming digital and first of the FIN.1100, as FIN.1010, family) for MRCA? I always assumed that the Harriers Ferranti FE.541 INAS (Kearfott derived gyros used in the Ferranti Miniature Inertial Platform) was what was meant as the definitive fit for the P.1154 (both were analogue) following the abandonment of the originally desired digital system? Ferranti FE.541 INAS became FIN.1065 when fitted with electronics from the FIN.1075 used in the GR.5 (modification made under RAE project Nightbird to upgrade T.4 to T.6 for GR.5 training), FIN.1075 was grossly unreliable and at least 32 Litton ASN-130s were acquired as a result. The original Jaguar system was replaced by the FIN.1064 which when rebadged for the Harrier became the FIN.1075. Nimrod MR2 got FIN.1012, FIN.1070 for EAP. Ferranti got to propose FIN.1063 in Buccaneer (FIN.1064 with weapons aiming circuitry redundant) with 60 units planned. FIN.1040 was exported to Japan for the Mitsubishi F.1. All from the FIN.1100 family.

Also, let us not forget civil aircraft, Elliots at least prototyped an INS for airliners and it was test flown on a BOAC 707, pre-production models called E.3 and E.5, the latter was marketed but I dont know how successfully. There was also an E.4 unit marketed at some point. I doubt they sold much, even VC-10's got the Delco Carousel systems- which later got shoe-horned into Vulcans for Black Buck.

Ferranti, IIRC, got Concorde prototype (production aircraft used the Ferranti-SAGEM SF 500-AESI). Phantom F-4M, in addition to the Harrier, used the miniature inertial platform which also made an appearance in ELDO and Black Arrow. A digital version was being touted in 1972 and was being referred to as Dins for awhile, probably forms part of the family tree to FIN.1100. Miniature Inertial Inertial Platform was more popular than NAVWASS as it was all in one box.

In a lot of cases UK companies only licensed the Gyros (admittedly a vital part of the system) not the entire INS for which they did a lot of their own work.
 
Some reflection with regard to English Electric,

As EE's inertial navigation efforts came out of the guided weapons division it seems most probable that the hoped for destinations were missiles. We know that for a while EE had a contract for an insurance inertial system for Blue Streak- that would explain the work done prior to the Honeywell agreement in 1958. Blue Water seems to be the best/only candidate for the Honeywell agreement, we know Blue Water had inertial guidance and we know that development started in the same year that the Honeywell agreement was signed, 1958.
 
sealordlawrence said:
Some reflection,

As EE's inertial navigation efforts came out of the guided weapons division it seems most probable that the hoped for destinations were missiles. We know that for a while EE had a contract for an insurance inertial system for Blue Streak- that would explain the work done prior to the Honeywell agreement in 1958, post 1958 Blue Water would seem to be the best candidate (development having started in 1958).

Might have also been aimed at a actual or projected drone project.
 
EE: Moore/II,P.108: 1955 Blue Streak "Sperry and EE for inertial guidance". P.108: By 1958 "EE had been eliminated from (Blue Streak's) guidance programme and only Sperry remained...Sperry had eventually to buy in (US gyro) designs from Kearfott, manufactured under licence in EDI by Ferranti".P.140, 1/61: O.R.1182 (Pandora/X-12: Air Staff "were able to capitalise on EE's work on Blue Water inertial guidance". P.130 (1958) Blue Water project was given to EE who built up design teams at Luton and Stevenage..inertial guidance (was required)".

Ferranti TSR.2 INS had 2-Honeywell and 1xFerranti/Kearfott gyros. EE had 2 Stevenage sites: the gyro clean room in Town Centre, by the magic roundabout, and the site to which the Napier/Luton GW team relocated in 1954, on (to be) A1(M). We are allowed to be confused.
 
Ken,

Thankyou for the reply, that roughly correlates with my theorising: May I be so bold as to ask which Moore you are qouting and from which title?

To finally confirm my theory:

"...but with the advent of the company's Blue Water project, with an inertial guidance system, it was decided to obtain a license for the Minneapolis-Honeywell miniature integrating gyroscope..."

From: http://www.flightglobal.com/pdfarchive/view/1961/1961%20-%200602.html

Based on Humphrey Wynn, it seems like the EE Blue Streak guidance died in early 57 at the latest and at the same time as the Marconi radar guidance.

To add, SG Brown got Sea Vixen with the Master Reference Gyro, may have had a monopoly for a while, SG Brown played with Bendix too- I have a note, possibly from Flight saying they hoped to sell in Europe- speculative? Last shot at getting back their 50s monopoly?

So TSR-2 INS is Ferranti Type 100. If anything from TSR-2 made it into Tornado it was the Ferranti-Kearfott gyroscope- but even that had undergone significant changes by then.

Interestingly, the Delco Carousel was also put in the Nimrod R1.
 
sealordlawrence said:
Elliots ultimately got Jaguar (E.3R- total nav/attack system package was NAVWASS) and Nimrod (E.3 platform).

I think that the NAVWASS system used a novel "rotating platform" technique where the whole instrument package rotated so that gyro drift would be nulled out (meaning that cheaper/poorer performance sensors could be used). Unfortunately this meant that all the interface signals had to pass over slip rings: any electrical noise on these slip rings was interpreted by the nav computer as a fault and the system had a tendency to "dump" on take off. As a result of complaints by the Jaguar pilots, the system was subsequently replaced by the Ferranti FIN 1075. The Nimrod system was also eventually replaced by a Ferranti unit (2 x FIN 1012s from memory)

sealordlawrence said:
I understood the Tornado/TSR-2 link to be the following: the TSR-2 system was in some way adapted for the Harrier and that system was then further developed (becoming digital and first of the FIN.1100, as FIN.1010, family) for MRCA? I always assumed that the Harriers Ferranti FE.541 INAS (Kearfott derived gyros used in the Ferranti Miniature Inertial Platform) was what was meant as the definitive fit for the P.1154 (both were analogue) following the abandonment of the originally desired digital system?


The FE541 Inertial Navigation and Attack System was fitted to all RAF and US Marine Corps Harrier GR1s (and retained on RAF Harrier GR3s) and was completely analogue. It used floated Kearfott type 125 gyros (maybe built under license I cant remember) but the navigation and weapon computers were purely home-grown Ferranti designs. The system comprised an Inertial Platform (IP), a Present Position Computer (PPC), a Weapon Aiming Computer (WAC), a Ballistics Box (BB), a Navigation Display Computer (NDC = a 35mm film-based moving map display) along with a pilot's control unit and a Power Supply Unit. The Ballistics Box was given a digital upgrade in the late 1970s. The IP, PPC, WAC and PSU were re-used for the UK Phantom INAS.
The US marines eventually dumped the system because "it was too complicated", and the ex-USMC equipments were refurbished and supplied to the RAF as spares in the early 1980s.

The whole system was a watchmaker's nightmare, full of servo shafts, motors, resolvers, tachogenerators, banks or electromechanical relays etc etc. The NDC was particularly fiendish to work on. Wire-wrap joints were used extensively to improve reliability, so removing a single module from the WAC or PPC (eg) would involve the removal of >60 wire wraps!

For the Harrier GR3, the INAS was integrated with the Ferranti LRMTS (Laser Ranger and Marked Target Seeker) and the pilot could carry out a completely automatic planned attack if the target was marked with the Ferranti LTM (Laser Target Marker). If the target wasn't being marked, laser range was still available. This system was still in use during the Falklands conflict in 1982.

sealordlawrence said:
Ferranti FE.541 INAS became FIN.1065 when fitted with electronics from the FIN.1075 used in the GR.5 (modification made under RAE project Nightbird to upgrade T.4 to T.6 for GR.5 training), FIN.1075 was grossly unreliable and at least 32 Litton ASN-130s were acquired as a result. The original Jaguar system was replaced by the FIN.1064 which when rebadged for the Harrier became the FIN.1075. Nimrod MR2 got FIN.1012, FIN.1070 for EAP. Ferranti got to propose FIN.1063 in Buccaneer (FIN.1064 with weapons aiming circuitry redundant) with 60 units planned. FIN.1040 was exported to Japan for the Mitsubishi F.1. All from the FIN.1100 family.
That's all basically correct. The FIN 1063 system was abandoned when the Bucc was taken out of service. From memory, FIN1075's problems were due to over-sensitive BIT circuitry, rather than inherent unreliability.

sealordlawrence said:
Ferranti, IIRC, got Concorde prototype (production aircraft used the Ferranti-SAGEM SF 500-AESI). Phantom F-4M, in addition to the Harrier, used the miniature inertial platform which also made an appearance in ELDO and Black Arrow. A digital version was being touted in 1972 and was being referred to as Dins for awhile, probably forms part of the family tree to FIN.1100. Miniature Inertial Inertial Platform was more popular than NAVWASS as it was all in one box.
And the Ferranti IP didn't suffer from the "platform dump" problem.....
 
Newboy1,


Thanks for the additional detail. I had a conversation with an interesting fellow I met at Paris this year who was an ex Harrier engineer and nav-attack systems came up, following a brief exchange I proposed that the INAS system displayed two characteristics and he agreed:


1) The system was more ambitious than the aircraft that ultimately ended up carrying it


2) It was typically British in that it was somewhat over-engineered and overly complicated


I would be interested to know your thoughts?
 
I couldn't really disagree with those comments. It always seemd to me that it had started out as a basic inertial nav system, and that the weapon aiming and moving map functions were "bolted on" later.

In terms of actually operating the system, it was probably too much for the pilot to handle alone. There were numerous different operating modes This was pre-HOTAS, and I seem to remember 1 pilot commenting that it could take up to 20 consecutive switch selections to get it into a particular planned attack mode. Since he would typically be flying at 200ft/450kts, this was a pretty heavy workload. The yanks certainly couldn't handle it, and they were generally flying much higher. All they really wanted/needed was a manual variable depression bomb sight. With the AV8B they got the Hughes Aircraft Angle Rate Bombing System (ARBS) which was at least controlled via the HOTAS.

Although a variant of the INAS was fitted to the RAF Phantom, that aircraft's (QRA) role didn't really involve dropping ordinance, so they never used the weapon aiming functions. They only needed a nav system which could be aligned in under 2 mins (and it could be!).

Over-engineered? I always thought that the system probably took analogue computing as far as it could go. It was certainly a very complicated system, but solving the navigation and weapon aiming equations in 1960s analogue computers was always going to be complicated. In electronic terms, this was pre-"op amps" and each amplifier was constructed of individual (silicon) transistors, diodes and resistors. There wasn't the option of simply selecting an appropriate integrated circuit from the Burr Brown catalogue. If you wanted (eg) an ac modulator or dc mutiplier it had to be designed from scratch. (I even remember 1 circuit which used a big resistor network to generate a x cos squared function in the PPC.) My exposure to it was long after the design had been completed, but I was full of admiration for the designers - they crammed a lot of stuff into a very limited volume. (There was a heading servo shaft in the Power Supply simply because there was no space for it in the Weapon Aiming Computer). There was also no space in the Ballistics Box to store all the different weapon characteristics, so there were "Ballistics Plugs" for each weapon. These could be interchanged at 1st line to cope with differing weapons loads in between sorties. (The plug for the 30mm Aden Gun was fixed).

Somewhere I've got an old Ferranti sales/technical brochure for the Harrier system - I'll try to dig it out.

I suppose it reflected the times, but the INAS was supported by a similarly complicated suite of test gear - the RAF did their own 2nd and 3rd line repairs and there were test sets for each LRU and even each module. There was even a clean room at 30MU where the Inertial Platforms were stripped down and repaired down to instrument cluster level. 4th line Platform repairs were handled at Ferranti in Edinburgh.

sealordlawrence said:
Newboy1,

Thanks for the additional detail. I had a conversation with an interesting fellow I met at Paris this year who was an ex Harrier engineer and nav-attack systems came up, following a brief exchange I proposed that the INAS system displayed two characteristics and he agreed:


1) The system was more ambitious than the aircraft that ultimately ended up carrying it
2) It was typically British in that it was somewhat over-engineered and overly complicated


I would be interested to know your thoughts?
 
Ken,

I do not know if you are still interested in this but I will add to this thread anyway. I have just received British Aircraft Corporation: A History by Charles Gardner and it holds some information that is pertinent to this topic:

1951: John Noble and Roy Hurrell devised a gyro for Thunderbird- supposedly this was the beginning of the Precision Products Group
1960: Stevenage clean room was opened, 'this was a factory without peer in Europe'
1961: License from Northrop for Beryllium gyros for naval applications
1975:BAC bought out the future royalties for the Honeywell license because BAC 'became so well established in the field'
 
And to track sideways for a moment - the Black Arrow satellite launcher had a Ferranti inertial guidance which I think was a modified TSR2 system.
 
Ferranti made the AHRS for both ELDO (SF600) and Black Arrow (FE650), probably derived heavily from TSR-2 work using the Kearfott derived Gyros. Ferranti Type 121 gyro was used in Skylark. Supposedly Ferranti sold some 700 Type 120 derivatives into TSR-2, Blue Streak and Blue Steel.
 
EE was to have had the parallel SLV/LRBM programme to de Havilland Propellers Blue Streak.
By the time the contracts were given EE/Delta3 was reduced to that of a insurance technical backup to dHP.
I understand an exact reversal of the situation in the States with Atlas and Titan programmes.
The EE and dHP were tasked with systems that had mix and match assemblies, propulsion, propellant tanks, re-entry head, and guidance/control.
We know that this policy was put into practice with the EE tasked stealth re-entry head replacing the dHP tasked bluff re-entry head.
EE propellant tank was the first component to be dropped.
The propulsion Bristol Delta 3 187,500 lbf engine stopped in 1957 but work on details continued up till 1966 .
EE guidance package included a celestial update navigator this was because the missile was sized for a significantly greater range .
The evidence then contradicts its self, one source says the EE inertial guidance component lasted up to 1957 yet another reports the guidance work lasting up to the time of BS cancellation because of difficulties with the primary system and to take advantage of the increased range possible with the smaller warhead. ( Ian Smith stated it could reach any were in the USSR from UK launch sites).
I clearly remember three occasions when LRBM guidance developments being reported/discussed on the wireless in 1957/1958/1959 but not the details.
The EE LRBM was reported, alluded to well before the dHP Blue Streak programme was officially made public, The only reference that I can find now is in a book by Burgess .
 
Last edited by a moderator:
Blue Streak FLIGHT, 29 August 1958

“Guidance is obviously going to be purely
inertial, unless some still newer system has
been invented. Sperry have not previously
been associated with complete inertial
systems in this country (and only English
Electric, who hold a Kearfott licence, and
Minneapolis-Honeywell have expressed
their ability to produce inertial-quality
gyros).
What was the Minneapolis-Honeywell system?

Another thought what type of Guidance was to be incorporated in the English Electric Black Rock missile before its cancellation?
 
Spark said:
What was the Minneapolis-Honeywell system?

GG49D Miniature Integrated Gyroscope, license acquired by English Electric in 1958.

Apparently Litton, Elliots and Ferranti all competed for the P.1154 contract, there was some controversy surrounding the Litton offering due to reports from Germany that the LN3 had suffered from poor reliability, however this was contradicted by Canadian experience.
 
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Hi there, maybe this post is a little late, but I just came accross this thread which I
found very interesting. My hobby is vintage avionics and I restored a FIN1012 to
working condition and via a homebrew logger/debugger it now controls the original
35mm film based moving map display. You can find a video on this project here:

View: https://www.youtube.com/watch?v=-EQqfxiGgd8


Although I have a good understanding on the internals of these systems now, I'd
be highly interested getting in touch with someone who knows on manufacturing and
facory-calibration of the platforms. They are really a masterpiece of engineering
and the FIN101x's are a great mix of precision mechanics, analog and digital computing!

Any hints are welcome,

Erik,

www.baigar.de,
erik@baigar.de,
www.programmer-electronic-control.de
 
Unfortunately I cannot help with your request, but I'm lost in admiration at your patience and ingenuity! Watching that gyro-package move as you're handling it in that video is hypnotic!
 
Thanks for the positive words... I think wihin the next year I will do another video with more detailed views of
the mechanics in action (esp. during alignment and moving it around). A friend is working on the original HUD and
if this will be fed by the navigator, this will be another video, too...

Unfortunately I did not get any feedback on possible ex-Ferranti empliyes so far, still remembering these
systems... :'(
 
Just trying to bump this thread up a bit and trigger some further discussion. I'm trying to compile a brief summary/history of Ferranti INS data/FIN numbers etc just for prosperity.

Can anyone add to any of the info already presented? ie what was the FE designation number for the Phantom INAS? Were the Black Arrow/ELDO systems complete platforms or did Ferranti just supply the gyros into those programmes? What was provided for "Skylark"?

I worked on the Harrier/Phantom INAS equipment in the late 70s/early 80s (as a bright-eyed bushy-tailed new physics graduate!) and fondly remember being considered part of the "valve and relay" department. That equipment was surely the pinnacle of Ferranti's work in the field of analogue military electronics! One of my first jobs was redesigning part of the Phantom navigation computer to replace Resistor-Transistor Logic (RTL) circuit cards with TTL devices!
I was also involved in the FINRAE system, which was designed and built in 3 weeks then shipped to the South Atlantic for the Falklands War in 1982.
 
I started work at Ferranti's Silverknowes factory in Edinburgh in 1973, where the INS systems were made and worked there for many years. My understanding is that the principal advantage Ferranti had was due to the power and easpecially the "flatness" of the synchro and servo motors that controlled the gimbals. This allowed the platform to be much smaller than competitors'.

It's been so long that I can't remember all the variants but there are 2 versions that are certainly missing from your discussion:-

The first is the PADS, Position and Azimuth Determination System. Hundreds were supplied to the British Army for artillery aiming. The unit would be fitted to a light vehicle and taken to a forward OP. A laser collimater would fix the target location into the PADS. The vehicle would then drive to the howitzers' location and it would update the guns with the correct settings use with howitzers. They even had a harness to attach the unit to a camel!

They modified this for use in tanks but it didn't sell. Shortly after the Israel-Egypt war, in which many Egyptian tanks got hopelessly lost, the sales team were trying to sell to both sides. One day, someone made a terrible mistake and generals from BOTH sides were invited to visit on the same day. Literally everyone in the factory was involved in keeping these groups apart. It was like a Brian Rix farce.

The other IN missing from everyone's lists is the 38B. We got a top secret contract to supply a missile guidance system to S. Korea. It consisted of, if I remember, about 30 platforms and 3 control units, which were pretty much Tornado ones. I do remember a day when some senior american military people turned up demanding to know what Project 38B was! I never could understand why they had to give it a name that hinted at its real purpose. (Korea is divided along the 38th parallel, of course.)
 
I started work at Ferranti's Silverknowes factory in Edinburgh in 1973, where the INS systems were made and worked there for many years. My understanding is that the principal advantage Ferranti had was due to the power and easpecially the "flatness" of the synchro and servo motors that controlled the gimbals. This allowed the platform to be much smaller than competitors'.

It's been so long that I can't remember all the variants but there are 2 versions that are certainly missing from your discussion:-

The first is the PADS, Position and Azimuth Determination System. Hundreds were supplied to the British Army for artillery aiming. The unit would be fitted to a light vehicle and taken to a forward OP. A laser collimater would fix the target location into the PADS. The vehicle would then drive to the howitzers' location and it would update the guns with the correct settings use with howitzers. They even had a harness to attach the unit to a camel!

They modified this for use in tanks but it didn't sell. Shortly after the Israel-Egypt war, in which many Egyptian tanks got hopelessly lost, the sales team were trying to sell to both sides. One day, someone made a terrible mistake and generals from BOTH sides were invited to visit on the same day. Literally everyone in the factory was involved in keeping these groups apart. It was like a Brian Rix farce.

The other IN missing from everyone's lists is the 38B. We got a top secret contract to supply a missile guidance system to S. Korea. It consisted of, if I remember, about 30 platforms and 3 control units, which were pretty much Tornado ones. I do remember a day when some senior american military people turned up demanding to know what Project 38B was! I never could understand why they had to give it a name that hinted at its real purpose. (Korea is divided along the 38th parallel, of course.)
"son of PADS" is still in production in Edinburgh as LINAPS, now using ring laser gyros. The 38B project was also called FIN1018E/FIN1018S and later developed into FIN1048E/FIN1048S.....I think total production was about 100 systems in the end.
 
I couldn't really disagree with those comments. It always seemd to me that it had started out as a basic inertial nav system, and that the weapon aiming and moving map functions were "bolted on" later.

In terms of actually operating the system, it was probably too much for the pilot to handle alone. There were numerous different operating modes This was pre-HOTAS, and I seem to remember 1 pilot commenting that it could take up to 20 consecutive switch selections to get it into a particular planned attack mode. Since he would typically be flying at 200ft/450kts, this was a pretty heavy workload. The yanks certainly couldn't handle it, and they were generally flying much higher. All they really wanted/needed was a manual variable depression bomb sight. With the AV8B they got the Hughes Aircraft Angle Rate Bombing System (ARBS) which was at least controlled via the HOTAS.

Although a variant of the INAS was fitted to the RAF Phantom, that aircraft's (QRA) role didn't really involve dropping ordinance, so they never used the weapon aiming functions. They only needed a nav system which could be aligned in under 2 mins (and it could be!).

Over-engineered? I always thought that the system probably took analogue computing as far as it could go. It was certainly a very complicated system, but solving the navigation and weapon aiming equations in 1960s analogue computers was always going to be complicated. In electronic terms, this was pre-"op amps" and each amplifier was constructed of individual (silicon) transistors, diodes and resistors. There wasn't the option of simply selecting an appropriate integrated circuit from the Burr Brown catalogue. If you wanted (eg) an ac modulator or dc mutiplier it had to be designed from scratch. (I even remember 1 circuit which used a big resistor network to generate a x cos squared function in the PPC.) My exposure to it was long after the design had been completed, but I was full of admiration for the designers - they crammed a lot of stuff into a very limited volume. (There was a heading servo shaft in the Power Supply simply because there was no space for it in the Weapon Aiming Computer). There was also no space in the Ballistics Box to store all the different weapon characteristics, so there were "Ballistics Plugs" for each weapon. These could be interchanged at 1st line to cope with differing weapons loads in between sorties. (The plug for the 30mm Aden Gun was fixed).

Somewhere I've got an old Ferranti sales/technical brochure for the Harrier system - I'll try to dig it out.

I suppose it reflected the times, but the INAS was supported by a similarly complicated suite of test gear - the RAF did their own 2nd and 3rd line repairs and there were test sets for each LRU and even each module. There was even a clean room at 30MU where the Inertial Platforms were stripped down and repaired down to instrument cluster level. 4th line Platform repairs were handled at Ferranti in Edinburgh.

sealordlawrence said:
Newboy1,

Thanks for the additional detail. I had a conversation with an interesting fellow I met at Paris this year who was an ex Harrier engineer and nav-attack systems came up, following a brief exchange I proposed that the INAS system displayed two characteristics and he agreed:


1) The system was more ambitious than the aircraft that ultimately ended up carrying it
2) It was typically British in that it was somewhat over-engineered and overly complicated


I would be interested to know your thoughts?
Jacko56

I worked on the PPC Line at 30MU, in 1982-we repaired the individual Module boards to component level. We also had to rush a Mod through the Module E-1st Stage Integrator, for the Harrier when the Falklands kicked off-someone foresaw that the RAF Harrier would end up flying off carriers, and the Mod allowed them to run the INAS up, of the ship's SINS.
The Modules in the PPC (common to the Harrier, and Phantom):

Module A-Latitude 2nd stage Integrator
Module B-The 'Corrections' Module that was mentioned previously?
Module C-Latitude channel Amplifier
Module D-Longitude channel Amplifier
Module E-Ist stage Integrator for both Lat/Long Channels-Module split in 1/2 with indentical components.
Module F-Longitude 2nd stage Integrator.
The LRU box also held the 'Motherboard', that all the Modules mated with-and wire-wrapping them all back in was a major job.

Hope this is usefull?
 
PRODUCTION PLATFORMS DELIVERED IN YEARS:DELIVERED FROM EX PRODUCTION STOCK
19671968196919701971197219731974197519761977197819791980198119821983198419851986198719881989199019911992199319941995199619971998199920002001YEAR TOTALS/N TOTAL
TORNADO391414832484049831621531912312151621236741263174253312717721772
NIMROD171313921162120164611194194
JAGUAR1844357050565151221032367367
NAVHAR157825151616912614125125
NAV/INDIA2924141144646
PADS MK111331439466860443282282
PADS MK21211113152439543521174177
PADS SAUDI1721010
FILS7231212
LNS24941919
GR582345281129567162162
INAS1445891016758702912218496496
CAS/SURV13122221313
38A KITS222
38A333
38B15139105514949
1048E888
1048S26245050
JAE26541717
FIN10181122
SKYLARK111
ARIANE233457248558513517171
14458910168648144292965788316219430229934035633129428118098585051152533127023875
 
I worked in the Inertial Platform Department from 1982 ~ 2003 (Silverknowes Edinburgh) then moved to Crew Toll in 2003 ~ 2016 (when the Last Tornado IN was repaired) - Above is the Production New Build figures . When I get a chance I will post some more info on the various FIN numbers.
 
PlatformProjectFIN
INAS3854/01833
TORNADO3854/360033854/360021010
NIMROD3854/37002
0812​
1012
NAVHAR3854/38003
0710​
1031B
3854/390031018
PADS MK13854/400031092
FILS3854/40141
PADS MK23854/40501
0857​
1095
38A3854/420011018E
38B3854/420031018S
PADS SAUDI3854/430031092A
BUCANEER3854/450031063
JAGUAR3854/450031064
LNS3854/45301
NAV/INDIA3854/48003
0811​
1031E
GR53854/750011075
GR53854/75401
0831​
1075
GR53854/755011075
GR53854/756011075
GR53854/757011075
CASING SURVEYOR3854/77987
ARIANE3962/060011082
ARIANE3862/132011082
1048S3862/25901
0715​
1048S
1048E3862/26901
0717​
1048E
38A KITS?
JAE?
FIN1018?
SKYLARK?
 
Amazing information, Alan - thanks for sharing! That is an awesome survey and sad that only a limited selection survived. Here some impressions from my "inventory":

Would love having one of the white Ariane platforms with the associated computer/driver box!
 
To those interested in more details: Here a video I took during repair, showing the instrument cluster of a FIN1012 from all sides - clearly visivle are the three grey cylinders are the gyros (type 125 floated gyro partially made from Beryllium) and the three smaller black-silver ones the accelerometers (floated type, FA2F) and the PCB holds temperature stabilization and pre-amps:
View: https://www.youtube.com/watch?v=IwCEVWR6lRE

A question I got asked several times in the demonstration sessions I held: Can analog computers crash? The FIN1010 consists of a prefect mixture from mechanical computing (e.g. 1st integration of rate to angle is done witin the gyros), analog electronic computing (OpAmp circuits to integration of acceleration to speed and even trigonimetric functions in azimuth resolution) and a 32bit bit serial computer. Indeed there is a situation in which the analog computer can "crash" leading to the platform going crazy during alignment as can be seen here:
View: https://www.youtube.com/watch?v=UfbGGBORGBg
(everything normal, but at time code 0:14 it starts to get confused). Interesting fun-fact: In later versions of the PCBs, that "bug" was fixed to some extent and for reference here a video, what it should like normally (at 0:18 the alignment of local vertical using accelerometers is finished and gyros are gettin spun up for gyrocompassing):
View: https://www.youtube.com/watch?v=3QRmetETRO4


2021 my demonstration system collapsed and intensive debugging pointed me to a broken gyro and replacing that one is an ongoing project (probably my most challeinging one) requiring creation of elaborate electronic und mechanical tooling to achieve proper alignment, but there is fantastic learning involved:
(1) Three decks of electronics (left) and the cluster mounted on a vibration insulated plate with own quick-connect contacts to avoid excessive wire wrapping (right):
1691316197322.png
(2) Lowest electronic dev (gyro drive stage, power supplies, first CPU); right side cluster completely wired and protected from dust under an acrylic bowl:
1691316302125.png
 
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Amazing information, Alan - thanks for sharing! That is an awesome survey and sad that only a limited selection survived. Here some impressions from my "inventory":

Would love having one of the white Ariane platforms with the associated computer/driver box!
 
I don't think any of the Ariane Platforms exist - they all went into Space!

Cheers

Believe me ;) - I have seen one in the post-Ariane 3 era together with the driver/computer. Will dig out a picture tomorrow and I am really worried that it will be lost in the future, but I lost trace of it :(
 
I don't think any of the Ariane Platforms exist - they all went into Space!

Cheers

Here a picture of a set of platform and DISC I have taken myself in around 2017 - that one did not go to space:

1691470614401.png

By the way - here are plenty of INAS platforms and one FIN1064 fragment in sad condition on eBay right now: SEARCH
1064:
1691470801365.png
INAS:
1691470862055.png
 
Just for reference I want to share some footage of the Ferranti guidance system used on the Ariane 1-3 (first half) making it the most accurate space launcher of its day:

1691682003513.png

Left picture shows the internals of the driver/computer (archaic 16/32 bit computer, not sure if bit-parallel or bit-serial) with the gimbaled platform. The right pictures shows the closed LRUs where in my opinion the computer may be a mock-up as the plugs on the front panel are definitively not real ;-) The original pictures with little bit of infomration on origin can be found on the Smithonian's pages:

https://edan.si.edu/slideshow/viewer/?eadrefid=NASM.1997.0014_ref7553
https://edan.si.edu/slideshow/viewer/?eadrefid=NASM.1997.0014_ref7551

The platform is very similar to what was used in Tornado, Nimrod, Jaguar, Phatom FGR.2, Harrier, Concorde Prototype and some others ;-)
 
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