Info on the Comet Smiths Flight director system
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Joined: Apr 2008
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From: East Anglia
Around 1975 at LHR an elderly Indian gentleman complete with turban would stand in the back of a mini truck and shine a high power pencil beam of light onto the L1011 radome...we would steer to remain attached to this beam and he would positioned us to either the takeoff point on the runway for a LVP departure or to the terminal finger so we could let our passengers off....the ground radar voice steers we had practiced in the sim coordinated and monitored (blind) with the ground run monitor and taxi chart in the cockpit did not in practice work.
On one occassion my friend in his L1011 was positioned several times first to 27L and then over to 27 R for 90mins in an attempt to get legal Takeoff vis...sitting on stand we thought it hilarious as we heard him creeping back and forth at 1.5 kts in the turns and 3 kts on the straight bits following the beam of light...luckily for us there was only one light and one Indian available and most of our passengers did not make it to the airport before we ran out of duty hours.
On one occassion my friend in his L1011 was positioned several times first to 27L and then over to 27 R for 90mins in an attempt to get legal Takeoff vis...sitting on stand we thought it hilarious as we heard him creeping back and forth at 1.5 kts in the turns and 3 kts on the straight bits following the beam of light...luckily for us there was only one light and one Indian available and most of our passengers did not make it to the airport before we ran out of duty hours.
the lunatic fringe
Joined: May 2001
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From: Everywhere
Trident G-ARPB carried out the first Cat 3B landing at Heathrow (28L) on 4th Nov 1966
The first TriStar was delivered to Eastern Air Lines on April 26, 1972.
The first TriStar was delivered to Eastern Air Lines on April 26, 1972.
Have to hand it to the British, they did all the early development work toward autoland capability, something most have easily forgotten...or never knew.
Last edited by L337; 30th July 2008 at 20:32. Reason: addition
Joined: Oct 2008
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From: London
Smiths Flight System
I realise I'm very late to this topic, but I only came across it recently, and joined PPRuNe specially to reply.
I'm the chap who wrote the (woefully inadequate) page on the Smiths Flight System, referred to by EGHH. I've since read an awful lot more about it, and replaced the page with a complete section. If there are any howlers, please let me know! The new section starts here:
The First Autopilots
In answer to 40&80: I have manuals for the Comet 4 that cover the Smiths Flight System. Not full detail; not the complete Smiths Instruments manual, but chapters in the Comet 4 Systems Manual, Operations Manual and Flying Manuals. Do let me know if you're still looking for more information. I might be able to help.
In answer to 411A: by really, really amazing coincidence, John A. Gorham, the British Smiths Instruments engineer who was project manager for installing the Military Flight System in the Vulcan, moved to Lockheed as Assistant Chief Engineer on the L-1011. Among other things, he proposed and managed the autopilot development.
So, 411A's post was not so far off-topic after all!
I'm the chap who wrote the (woefully inadequate) page on the Smiths Flight System, referred to by EGHH. I've since read an awful lot more about it, and replaced the page with a complete section. If there are any howlers, please let me know! The new section starts here:
The First Autopilots
In answer to 40&80: I have manuals for the Comet 4 that cover the Smiths Flight System. Not full detail; not the complete Smiths Instruments manual, but chapters in the Comet 4 Systems Manual, Operations Manual and Flying Manuals. Do let me know if you're still looking for more information. I might be able to help.
In answer to 411A: by really, really amazing coincidence, John A. Gorham, the British Smiths Instruments engineer who was project manager for installing the Military Flight System in the Vulcan, moved to Lockheed as Assistant Chief Engineer on the L-1011. Among other things, he proposed and managed the autopilot development.
So, 411A's post was not so far off-topic after all!
Joined: Feb 2020
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From: Chicago
I have built a full-scale, fully-functioning Vulcan flight simulator. It's very amazing (I just joined PPRUNE, and it won't allow me to post photos until I have 10 posts).
I'm still trying to fine-tune the software code for the Director Horizon instrument, and I really don't understand how it works. Does anyone have any updated info on the Director Horizon, or training materials? Thanks for any info!
I'm still trying to fine-tune the software code for the Director Horizon instrument, and I really don't understand how it works. Does anyone have any updated info on the Director Horizon, or training materials? Thanks for any info!
Joined: Oct 2008
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From: London
Do you have a copy of the Vulcan B Mk.2 Aircrew Manual (AP 101B-1902-15)?
If not, Peter Gill at FlightManualsOnline is a very reasonably priced source of scans.
Chapter 12 of that manual gives a good outline of the Military Flight System (by Smiths) including the Director Horizon and Beam Compass.
It also references RAF manual 112C-0800-1B Automatic Pilot Mk 10 B/C, which you may be able to find on line. It may be too obscure to have been scanned, though, in which case you could ask RAF Hendon Museum, RAF Cosford Museum or BAE Systems Heritage at Farnborough, and plan a visit to the UK ...
Are you in touch with the Vulcan Simulator project here? I can't post a URL, but they have a Facebook page and have been modifying real instruments to operate as simulator instruments.
Otherwise it depends what you need to know. I have more information on the civilian version, the Smiths Flight System, including civilian Director Horizon and Beam Compass instruments. It has many similarities, but, crucially, the Director Horizon instrument was different.
Guy.
If not, Peter Gill at FlightManualsOnline is a very reasonably priced source of scans.
Chapter 12 of that manual gives a good outline of the Military Flight System (by Smiths) including the Director Horizon and Beam Compass.
It also references RAF manual 112C-0800-1B Automatic Pilot Mk 10 B/C, which you may be able to find on line. It may be too obscure to have been scanned, though, in which case you could ask RAF Hendon Museum, RAF Cosford Museum or BAE Systems Heritage at Farnborough, and plan a visit to the UK ...
Are you in touch with the Vulcan Simulator project here? I can't post a URL, but they have a Facebook page and have been modifying real instruments to operate as simulator instruments.
Otherwise it depends what you need to know. I have more information on the civilian version, the Smiths Flight System, including civilian Director Horizon and Beam Compass instruments. It has many similarities, but, crucially, the Director Horizon instrument was different.
Guy.
Joined: Feb 2020
Posts: 5
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From: Chicago
BoeingDriver99, a "tosser..." now, that's funny. Had to look up the meaning of that, since that's a British term.
Nope... not 411A, or whoever you're "tossing" about.
Genuinely looking for information on the Director Horizon and how it works. Maybe I need to source the Smiths instrument manual somehow.
Nope... not 411A, or whoever you're "tossing" about.
Genuinely looking for information on the Director Horizon and how it works. Maybe I need to source the Smiths instrument manual somehow.
Joined: Feb 2020
Posts: 5
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From: Chicago
Hi Guy, thank you. Yes, I've got the Mk.2 Aircrew Manual from Peter, and I've read the part about the Director Horizon a ton of times... still don't understand it. It's the kind of thing that one needs to see work in person. And, I've been in good contact with the folks who built the Vulcan sim in the UK -- great people! There seems to be some questions about its functioning, even on their part. I simply saw this thread, and I figured I'd ask around.
I'll check with the RAF museums and see if they have any old training materials on it. Thanks!
BTW, I helped dismantle Comet 4C N999WA (formerly XA-NAS) at KORD in the early 1980s and 1990s as a teenager... I still look at those photos wishing I could go back in time. The City Of Chicago destroyed the airplane, despite our plans to salvage it for the Smithsonian.
I'll check with the RAF museums and see if they have any old training materials on it. Thanks!
BTW, I helped dismantle Comet 4C N999WA (formerly XA-NAS) at KORD in the early 1980s and 1990s as a teenager... I still look at those photos wishing I could go back in time. The City Of Chicago destroyed the airplane, despite our plans to salvage it for the Smithsonian.
Joined: Mar 2006
Posts: 2,633
Likes: 137
From: USA
BoeingDriver99, a "tosser..." now, that's funny. Had to look up the meaning of that, since that's a British term.
Nope... not 411A, or whoever you're "tossing" about.
Genuinely looking for information on the Director Horizon and how it works. Maybe I need to source the Smiths instrument manual somehow.
Nope... not 411A, or whoever you're "tossing" about.
Genuinely looking for information on the Director Horizon and how it works. Maybe I need to source the Smiths instrument manual somehow.
Joined: Jun 2000
Aviation Qualifications: ATP+Mil
Posts: 4,698
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From: Australia
While on the subject of flight directors. The RAAF bought several new HS 748's in 1966. Two for the No 34 (VIP) Squadron at Canberra. The rest for the School of Air Navigation at RAAF East Sale. Around the same period the RAAF also bought two BAC One-Elevens and three Mystere Falcon 20's. The RAAF were talked into putting (I suspect by an enterprising Collins salesman) the Collins FD 108 into each of these aircraft.
In the case of the HS 748's, a difficulty soon arose integrating the Collins FD 108 system with the British Smiths autopilot system. What was originally planned as a four week 748 conversion course at Woodford, Cheshire (a pretty airfield in those days) finished up as a five month English holiday on full allowances for the two RAAF crews of the VIP Squadron (four pilots, two navigators and various maintenance personnel).
That holiday included a one day course at Weybridge courtesy the Collins flight director people. We were given lots of pretty brochures during the two hours of lectures in the morning. At lunch time it was down to the local pub for a slap-up extended lunch and unlimited grog. End of the Collins Flight Director course.
The HS 748 was not exactly a high speed turboprop. There was no way you needed a flight director system. The instrument panel that came with the prototype HS 748 G-ARAY was well laid out including the standard "Six Pack" of flight instruments. Not like the abortion of a cockpit layout as in the Viscount. I think the Viscount had Sperry zero readers back then. But someone must have conned the RAAF procurement officer into buying the Collins FD 108 for the RAAF HS748's
I say that because I believe the initial procurement chappie was an elderly Wing Commander with previous Dakota transport flying experience. He had been behind a desk for years. Not his fault he wasn't a current pilot and knew SFA about the advantages and disadvantages of flight directors.
We soon learned that blind reliance on flight director guidance could be a trap. Back at the squadron there were pilots who loved the FD 108 gimmicks like automatic 45 degree intercepts of the localiser and the fun of flying the "little aeroplane" into the V-Bars of the FD system. These pilots became addicted to using the FD and became multi-fingered switch flickers. Others soon realised their basic instrument scan in IMC was gradually being degraded because of the compelling presence of the flight director. So they simply switched it off.
The same situation exists today where basic raw data instrument flying skills have gone the way of the dinosaur leaving pilots to rely totally on FD guidance even on a sunny day. A few of us dinosaurs could see this coming way back in 1966.
In the case of the HS 748's, a difficulty soon arose integrating the Collins FD 108 system with the British Smiths autopilot system. What was originally planned as a four week 748 conversion course at Woodford, Cheshire (a pretty airfield in those days) finished up as a five month English holiday on full allowances for the two RAAF crews of the VIP Squadron (four pilots, two navigators and various maintenance personnel).
That holiday included a one day course at Weybridge courtesy the Collins flight director people. We were given lots of pretty brochures during the two hours of lectures in the morning. At lunch time it was down to the local pub for a slap-up extended lunch and unlimited grog. End of the Collins Flight Director course.
The HS 748 was not exactly a high speed turboprop. There was no way you needed a flight director system. The instrument panel that came with the prototype HS 748 G-ARAY was well laid out including the standard "Six Pack" of flight instruments. Not like the abortion of a cockpit layout as in the Viscount. I think the Viscount had Sperry zero readers back then. But someone must have conned the RAAF procurement officer into buying the Collins FD 108 for the RAAF HS748's
I say that because I believe the initial procurement chappie was an elderly Wing Commander with previous Dakota transport flying experience. He had been behind a desk for years. Not his fault he wasn't a current pilot and knew SFA about the advantages and disadvantages of flight directors.
We soon learned that blind reliance on flight director guidance could be a trap. Back at the squadron there were pilots who loved the FD 108 gimmicks like automatic 45 degree intercepts of the localiser and the fun of flying the "little aeroplane" into the V-Bars of the FD system. These pilots became addicted to using the FD and became multi-fingered switch flickers. Others soon realised their basic instrument scan in IMC was gradually being degraded because of the compelling presence of the flight director. So they simply switched it off.
The same situation exists today where basic raw data instrument flying skills have gone the way of the dinosaur leaving pilots to rely totally on FD guidance even on a sunny day. A few of us dinosaurs could see this coming way back in 1966.
Last edited by Centaurus; 14th February 2020 at 11:59.
Joined: Feb 2020
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From: Chicago
Centarus, excellent points. The flip side is this: flying a BE1900 for seven legs, 8 block hours, in a 12-hour duty day, in February, in the Great Lakes, with winter Thunderstorms, icing, windshear, and constant turbulence all day long -- with no autopilot, no flight director, and brown-bagging food and water. The result is arriving back at base at 1AM on the last leg, and on short final approach, the First Officer literally falls asleep while hand flying the aircraft on the ILS (I smacked him gently in the arm while yelling, "Wake up!"). This was not an unusual duty day -- this was regional flying in the 1980s and 1990s. Same thing on Metroliners and Jetstreams. Of course, the poverty pay and roach motels were icing on the cake.
So, this is a case where an autopilot and flight director really were needed. Yes, we were s***-hot with instrument-flying skills, but the end objective is to get the plane safely on the ground without bending any metal.
There was the Vulcan crash after the world tour in 1956, and although there were some poor choices made, one wonders whether a flight director would have been useful after that long and challenging flying.
So, this is a case where an autopilot and flight director really were needed. Yes, we were s***-hot with instrument-flying skills, but the end objective is to get the plane safely on the ground without bending any metal.
There was the Vulcan crash after the world tour in 1956, and although there were some poor choices made, one wonders whether a flight director would have been useful after that long and challenging flying.
