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-   -   Smiths electric pilot Sep.1 (https://www.pprune.org/aviation-history-nostalgia/273066-smiths-electric-pilot-sep-1-a.html)

tarrant 23rd Apr 2007 10:25

Smiths electric pilot Sep.1
 
Can anyone tell me what type of aircraft had the Smiths Electric Pilot Model SEP. 1.

Could it have been a Viking?

Many thanks

MReyn24050 23rd Apr 2007 13:04

Not sure about the S.E.P.1 I know that the Smiths S.E.P 2 was fitted to the Vickers Viscount. As following the accident of Viscount 803 Aircraft EI-AOM near Tuskar Rock, Co. Wexford on 24th March, 1968 an examination of components of the autopilot – a Smiths S.E.P.2 was done at Dublin Airport on 21st October, 1968.

A37575 25th Apr 2007 13:44

Not absolutely sure but I think the first Avro 748 had a Smiths SEP 1 when I first flew the prototype G-ARAY during conversion training in 1967. I do know that the VIP Avro 748's for the Royal Australian Air Force were fitted with the Collins FD 108 system and that Avro's had a difficult job interfacing the Smiths autopilot system with the Collins FD system.

tinpis 26th Apr 2007 01:14

Viscount had SEP II .
As did Argosy and Merchantman and I would presume any other piece of British Blacksmithing from that era.
Might be wrong here but believe it evolved into Collins ?
SEP II = Seldom Ever Performs Twice :hmm:
However personally found it worked very well once you got used to a few little quirks like "flying down towards yer boots"

Dan Winterland 26th Apr 2007 02:27

'Flying towards yer boots'. That brings back bad memories! Sounds the same as the Smiths MFS (Smiths Military Flight System) more commonly known as the Smiths Mystery Flight System - as fitted to the Victor and Vulcan Mk2s.

tinpis 26th Apr 2007 04:02


I would presume any other piece of British Blacksmithing from that era.
Dan I would guess you are right.:ok:

LFittNI 26th Apr 2007 18:35

Aaaaaah, analogue
 
The core of MFS was actually Mk.10 Autopilot, which in civilian clothes was SEP2.

SEP2 was also standard fit on the Britannia and Comet C Mk 4 in RAF trim, where SFS (Smiths Flight System) was fitted.

The only real difference between Mk.10 and SEP2 (apart from various gearing changes) was the absence of the "Bomb" facility.

SEP1 was, I believe (a little before my time) the RAF Mk. 9 autopilot--which appeared on the Comet C Mk.2. No flight system as was later known, just the Zero Reader......a wondrous binary driven machine.

Smith's at Cheltenham used to have a small museum of their wares--fascinating for those of a technical bent. You could also eye the girls from CLC from the office window.........

Blacksheep 27th Apr 2007 02:14

I can say with absolute certaintly that the Varsity - and therefor most likely the Viking - had an SEP 1 Autopilot. In 1977 I removed a complete system one from a Varsity on the burning pan at Northolt for donation to Southall College of Technology.

Yes LFittNI, the Smiths MFS used on Vulcans and Victors was based around the military version of SEP 2 rather than the SEP 1. That Rate/Rate platform was certainly the way to go for tight attitude control. After leaving the mob and moving onto American built machinery, I was astonished to find the Pioneer-Bendix PB20 used in the B707 was a displacement autopilot with rate feedback. Whatever happened to British avionics? We were the cutting edge in the fifties yet lost the plot entirely in less than ten years.

tinpis 28th Apr 2007 01:34


Whatever happened to British avionics? We were the cutting edge in the fifties yet lost the plot entirely in less than ten years.
"Whoever comes first ....fails"

Tinpis.

LFittNI 28th Apr 2007 12:37

Analogue, lovely analogue....
 
Blacksheep,

Yes, it's very sad to recall the demise. Caused, I believe, by two main factors--the prevalence of multi-nation aircraft programmes where political necessity forced a third-party avionics choice, and the late take-up of advanced semi-conductor technology in the UK.

I know that Elliotts tried to make a run with some very advanced (!) 8-bit technology post-TSR2, but found no takers.


A side-comment on the dear old Mk.10 autopilot----on the Britannia, the main amplifier unit was positioned by the Nav's leg, far too accessible for those wannabe techies. Balancing the mag.amps was a true art, as I'm sure you remember, not a science, and I lost count of the number of times I had to re-balance the pitch channel after the Nav tried to correct some minor (usually imagined)porpoise-ing whilst in flight.


One even asked me once if it would help if he "tried changing to the other gearing links"...........:hmm:

parabellum 29th Apr 2007 00:31

Wasn't it the Varsity with the SP1 that first did autolands? Thread here before about that, remember the b & w film though, Bedford or Cranwell I think, in real fog!

Dan Winterland 3rd May 2007 06:08

Cutting edge? Anyone who had to fly with the MFS may disagree. Clever it may have been, but it wasn't that good. For a start, it only had 18 degrees up and 9 degrees down pitch info - the Victor Mk2 could easily exceed those at light weights. The compass display was clever if you were intercepting a localiser, but that was about it.

I came to the MFS from the Sperry STARS system which was a modern (for the time) system which was far far better. The MFS was a bit of a shock when I first saw it. OK, for it's time it was advanced. But thankfully the displays used weren't used on any subsequent system and thus becoming the norm. They were an ergonomic nightmare and DP Davis in his book 'Handling the Big Jets' states that generally there were a fairly unsatisfactory system. As he was the head of CAA certification at the time, he may have led to their demise.

Incidently, the Mk2 V Bombers had a autoland system which used the Smiths autopilot and a system called L Cable which was an aerial which ran along the ground out as far as the middle marker. This was very advanced for it's time and I think the first operational use of an autoland system.

Shack37 3rd May 2007 15:04

LFittNI

I'd forgotten what nostalgia was until I read Mk9, Mk10 autopilots and Zero Reader all on the same thread!!
The Shackleton Mk2 had Mk9 (SEP1) and the Shack Mk3 was fitted with Mk10(SEP2).
Balancing the mag amps wasn't just an art, it was a black art. I seem to remember the crossfeed channel being a bit sensitive at times.

How about G IV B and G7 mag compasses and T3 Bombsights for memory lane?????????????

S37

Jayviator 15th May 2009 20:23

Gearing pad from Vulcan
 
Hi, I recently got a part of a Vulcan, called a gearing pad I am trying to find out about it, from another forum I have learnt it was part of the Smiths SEP11/ MK10 autopilot.
Could anyone tell me more about what function it had?
the writing on it reads
used on
CONTROL UNIT
aircraft
VULCAN 'B' MK 2
code 107 SUE/2
ref no 6TB/1728
ser no 449/64
It also says
SMITHS
gearing pad
type J
(pre amp A/S)

thanks
Jason

LFittNI 17th May 2009 16:52

If this is what I think it is, the Gearing Pad was fitted to the Mk.10/SEP2 Main Amplifier, and was accessible under a flap in the side.

Its main purpose was to alter the gearing ratios and feedback rates of the three main autopilot channels, pitch, roll and yaw, according to the required aerodynamic characteristics of the aircraft type it was fitted to. Each aircraft type would have its own specific pattern of links which altered the inductance dynamics of the magnetic amplifiers. AFAIR, it also enabled other attributes of the autopilot to be made "live" or not.

Thus, a standard piece of avionic equipment could be specified and ordered for many different aircraft types--good thinking, and a good example of early COTS.

Having written the above, I seem to recall it being referred to as "the Links Pad", so there is a chance that this example might be different!

Sorry m'lud, it's all a very long time ago...........

Jayviator 17th May 2009 21:22

Thansk for your reply,
it was very informative

tornadoken 17th May 2009 21:48

#10, LFNI: UK avionics demise due to: the prevalence of multi-nation aircraft programmes where political necessity forced a third-party avionics choice, and the late take-up of advanced semi-conductor technology in the UK. No demise: Smiths thrives in GE Aviation Systems, much of Ferranti and Elliott in SELEX/Finmeccanica.

No late take-up: Cat.IIIa, 12ft. decision height Autoland, Smiths on Trident/Belfast, Elliott on 1-11/VC10, slaved to Leader Cable at Brize Norton/LHR. First to market, where all then lapsed, in part due to clean-air removal of "dirty" coal (pea-souper smog now a dim memory), and in part to late-1950s' galloping pace of (now, IT): Autoland's early-1950s' origins at Bedford BLEU involved valves. TSR.2, Concorde, Sea Slug/Bloodhound/Thunderbird Mks.I SAMs were all adversely impacted by step-change in Automatic Data Processing. 1962 Bloodhound I "Affair": Ferranti had won pulse radar guidance, paid by MoS in 1953/4 to take licences from (AT&T)Bell Labs and Texas Insts. and thus become Europe’s 1st. supplier of silicon diodes by diffusion process. Fairchild’s planar/Bell’s epitaxial processes, ’58/60 led in ’61 to TI/Fairchild launch of medium-scale integrated circuits, applied by Ferranti in Bloodhound, omitting to mention it to MoA's pricers. £4Mn. repaid. They still won much on Tornado. Of 1960s' International Collaborative Projects (the alternative to which was no projects) Concorde was extensively Brit avionics; Jaguar 'S' had Elliott NAVWASS; Lynx has Elliott AFCS even in the Aeronavale variant. Tornado IDS was Elliott AFCS, TF 'E' scope and TV Tabular Display; Smiths HUD. Your 3rd. party choice point is presumably Elliott/Ferranti's loss of the Tornado Ground Mapping and Terrain Following Radars to TI, in R&D (they licensed their production/support). Both teams recovered from that setback. The digital data bus funded into Tornado, 1971, was in no way inferior to F-111A, F-15A. In exchange for US lead on the radar, FRG granted UK "excess" share of the rest of Tornado's common avionics suite, to UK's great benefit on Eurofighter.

CONSPICUITY 17th May 2009 22:41

Sep1 Autopilot
 
When I was first posted to Lossiemouth in 1972 my job was carrying out 2nd line servicing of the SEP1(MK9) autopilot system this was fitted to the 8 sqdn Shackletons and as i recall it was very similar to the Sep2 (MK10)except the gyro unit was completely enclosed unlike the Sep2s gold fish bowl gyro unit.

Blacksheep 18th May 2009 11:44


UK avionics demise due to: the prevalence of multi-nation aircraft programmes where political necessity forced a third-party avionics choice
In military aviation we can still see the remains of the British avionics industry, just as we can see the remains of our airframe capability in Airbus. However, in civil aviation where I work, there are three choices for avionics - Rockwell Collins, Honeywell and Thales. GB is limited to producing a few nice bits of very accurate test equipment.

avionic type 18th May 2009 19:53

The B.E.A. Viscount 701s Vikings,Elizabethans, were fitted with S.E.P.1 and the 802/806 Argosy , Vanguard and the Comet had the S,E.P.2


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