Research on the BAC 1-11 electrical systems
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Research on the BAC 1-11 electrical systems
quite a unusual question, following a request received from a Djibouti friend, studying in a local technical college ....
this young lady (yes, they do work in mecanical and electrical matters as well) is preparing a ''memoire'' related to the electrical distribution system of a One Eleven .... why this peculiar aircraft, would you say ?
just because her country just bought one !
any ideas where I could , on her behalf, collect such info on the internet....
you help will be greatly appreciated
Keskildi alias Gerald
(Keskildi being the french QRI user's surname when talking .. english abroad, kind of ''SAY AGAIN'' or ''what the f**** is he saying '' hence my callsign )
this young lady (yes, they do work in mecanical and electrical matters as well) is preparing a ''memoire'' related to the electrical distribution system of a One Eleven .... why this peculiar aircraft, would you say ?
just because her country just bought one !
any ideas where I could , on her behalf, collect such info on the internet....
you help will be greatly appreciated
Keskildi alias Gerald
(Keskildi being the french QRI user's surname when talking .. english abroad, kind of ''SAY AGAIN'' or ''what the f**** is he saying '' hence my callsign )
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Try the guy on 'Contact Me' below. He may point you towards some spare manuals.
http://bac1-11jet.co.uk/bac1-11jet.co.uk%20Contents.htm
http://bac1-11jet.co.uk/bac1-11jet.co.uk%20Contents.htm
Hi, Qu'est-ce-qu'il-dit,
Would be interested to know where Djibouti got their 1-11 from, and what model it is, if you have any info.
Regards,
'oo-eez-kolling
Would be interested to know where Djibouti got their 1-11 from, and what model it is, if you have any info.
Regards,
'oo-eez-kolling
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It's probably a -500 (seating capacity above 100 announced) but I wonder if it's an aircraft of Romanian or original manufacture
I don't know the serial number or reg yet
I'll let you know, of course
info, (in french, I'm afraid) about this new equipment...
La compagnie aérienne Djibouti Airlines vient de renforcer sa flotte avec l'acquisition d'un nouvel avion de Type BAC-1-11 qui desservira les pays de la région. Vendredi dernier, la piste de l'Aéroport International de Djibouti accueillait un nouvel appareil aux couleurs de Djibouti Airlines. L'appareil, de type BAC-1-11 d'une capacité de 104 passagers a été réceptionné à son atterrissage par MM. Nabil Deyfallah et Salam Goubari respectivement Directeur général et directeur commercial et marketing de la compagnie Djibouti Airlines. Ce nouvel avion doté d'une capacité d'accueil de 104 passagers, desservira à partir de Djibouti les vols à destination du Yémen, Dubaï, Somalie et l'Ethiopie.
Selon M. Salam Goubari, directeur commercial et marketing " par l'acquisition de ce nouvel appareil tout comme celle d'un autre programmé très prochainement, l'objectif de Djibouti Airlines est de renforcer ses capacités opérationnelles" précise t-il. Il s'agit aussi d'une exigence requise en matière de trafic aérien et pour se mettre en règle avec l'International Air Transport Association (IATA). Ce qui suppose que Djibouti Airlines doit mettre à niveau l'ensemble de ses appareils et de ses équipements. On se souvient qu'au mois de janvier dernier, Djibouti Airlines avait conclu à Sanaa un accord de partenariat avec la compagnie aérienne 'Yemenia'. En effet, dans le secteur du transport aérien, les seuls pavillons qui tirent leur épingle du jeu sont ceux qui ont su unir leurs forces pour défendre leurs intérêts ... ou qui en ont fait des partenaires plutôt que des concurrents. Djibouti Airlines semble retrouver des couleurs depuis son mariage réussi avec Yemenia
Pour preuve, les activités du transporteur local augurent déjà de nouvelles performances à la faveur de prestations de qualité répondant aux exigences les plus pointues. Cependant, pour s'adapter aux nouvelles exigences et faire face à une concurrence de plus en plus rude, il ne suffit pas de changer de logo ni même d'avoir une nouvelle image de marque mais plutôt de moderniser la gestion et d'assurer une nouvelle dynamique dans l'activité et c'est ce que justement l'équipe de Djibouti Airlines nous promet. "Outre les vols réguliers, nous comptons contribuer au développement du tourisme djiboutien et d'assurer la desserte vers des destinations touristiques grâce à une flotte composée essentiellement d'avions répondant aux besoins du marché local et aux vols régionaux" déclare le directeur commercial, Salam Djebari. Et ce n'est pas tout.
Parmi les actions que la compagnie compte entreprendre pour améliorer la qualité de ses services, la mise en place d'un système de vente et de réservation à distance via Internet. »
I don't know the serial number or reg yet
I'll let you know, of course
info, (in french, I'm afraid) about this new equipment...
La compagnie aérienne Djibouti Airlines vient de renforcer sa flotte avec l'acquisition d'un nouvel avion de Type BAC-1-11 qui desservira les pays de la région. Vendredi dernier, la piste de l'Aéroport International de Djibouti accueillait un nouvel appareil aux couleurs de Djibouti Airlines. L'appareil, de type BAC-1-11 d'une capacité de 104 passagers a été réceptionné à son atterrissage par MM. Nabil Deyfallah et Salam Goubari respectivement Directeur général et directeur commercial et marketing de la compagnie Djibouti Airlines. Ce nouvel avion doté d'une capacité d'accueil de 104 passagers, desservira à partir de Djibouti les vols à destination du Yémen, Dubaï, Somalie et l'Ethiopie.
Selon M. Salam Goubari, directeur commercial et marketing " par l'acquisition de ce nouvel appareil tout comme celle d'un autre programmé très prochainement, l'objectif de Djibouti Airlines est de renforcer ses capacités opérationnelles" précise t-il. Il s'agit aussi d'une exigence requise en matière de trafic aérien et pour se mettre en règle avec l'International Air Transport Association (IATA). Ce qui suppose que Djibouti Airlines doit mettre à niveau l'ensemble de ses appareils et de ses équipements. On se souvient qu'au mois de janvier dernier, Djibouti Airlines avait conclu à Sanaa un accord de partenariat avec la compagnie aérienne 'Yemenia'. En effet, dans le secteur du transport aérien, les seuls pavillons qui tirent leur épingle du jeu sont ceux qui ont su unir leurs forces pour défendre leurs intérêts ... ou qui en ont fait des partenaires plutôt que des concurrents. Djibouti Airlines semble retrouver des couleurs depuis son mariage réussi avec Yemenia
Pour preuve, les activités du transporteur local augurent déjà de nouvelles performances à la faveur de prestations de qualité répondant aux exigences les plus pointues. Cependant, pour s'adapter aux nouvelles exigences et faire face à une concurrence de plus en plus rude, il ne suffit pas de changer de logo ni même d'avoir une nouvelle image de marque mais plutôt de moderniser la gestion et d'assurer une nouvelle dynamique dans l'activité et c'est ce que justement l'équipe de Djibouti Airlines nous promet. "Outre les vols réguliers, nous comptons contribuer au développement du tourisme djiboutien et d'assurer la desserte vers des destinations touristiques grâce à une flotte composée essentiellement d'avions répondant aux besoins du marché local et aux vols régionaux" déclare le directeur commercial, Salam Djebari. Et ce n'est pas tout.
Parmi les actions que la compagnie compte entreprendre pour améliorer la qualité de ses services, la mise en place d'un système de vente et de réservation à distance via Internet. »
I got some of that. Certainly looks like a 500 srs in the photo. With the temperatures in the region, I wonder if they will be using the dreaded de-min water injection system (if fitted). It used to be a pain in the neck when operating charters between the UK and Spain in the summer, but I think we were carrying about 110+ pax.
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Pigboat,
One of our FTEs worked on the Dee Howard conversion. He had a video taken inside the cabin in flight - the interior noise was MUCH lower even with the toilets removed. When I was at BAC, there was a proposal to put JT8Ds on in production instead of the Speys - what might have been. Still wonder what an updated 1-11 with RR710s would do.
One of our FTEs worked on the Dee Howard conversion. He had a video taken inside the cabin in flight - the interior noise was MUCH lower even with the toilets removed. When I was at BAC, there was a proposal to put JT8Ds on in production instead of the Speys - what might have been. Still wonder what an updated 1-11 with RR710s would do.
Yes, the airframe is very robust, I think (like its much bigger stable-mate). The engine, excellent for 1965, was the main drawback by the late '70s. Apart from the noise, the hot-weather performance was embarrassing. You had to load about 80 kgs of de-min water to gain about 200 kgs improvement in RTOW, if memory serves. Net gain, about 1 or 2 passengers.
Guess the Schiphol guys finally knocked the Tay idea on the head with the F100?
Guess the Schiphol guys finally knocked the Tay idea on the head with the F100?
Yes, the airframe is very robust...
I remember that Dee Howard proposal. At the time, rumour had it he had been talked out of further development by Gulfstream. A Tay-engined 1-11 would have made the G3 look very unattractive for corporate operators.
A small anecdote about the Spey. My late friend Eric Appleton of RR loved the engine, but he allowed it was Rolls-Royce's greatest momument for turning expensive petroleum products into noise.
Last edited by pigboat; 1st May 2008 at 13:48.
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Bac 111
"A small anecdote about the Spey. My late friend Eric Appleton of RR loved the engine, but he allowed it was Rolls-Royce's greatest momument for turning expensive petroleum products into noise."
I think the Dart did it better!
The expert in the States on 1-11s was Arthur Trowbridge if he's still around. He was originally with Hunting and knew everything about them, working as a free lance consultant for the corporate operators. Based in Texas if I remember correctly. He would most certainly have the answers.
I think the Dart did it better!
The expert in the States on 1-11s was Arthur Trowbridge if he's still around. He was originally with Hunting and knew everything about them, working as a free lance consultant for the corporate operators. Based in Texas if I remember correctly. He would most certainly have the answers.
I think the Dart did it better!
Eric was with RR in Montréal, then was seconded to Mohawk when they acquired their BAC1-11's. It was supposed to be a six-month leave, but he was still there 20 years later. He also instructed on the Dart at the then Allegheny Airlines, after the merger of the two, which is where I met him.
Last edited by pigboat; 2nd May 2008 at 23:25.
Chris Scott:
Guess the Schiphol guys finally knocked the Tay idea on the head with the F100?
Guess the Schiphol guys finally knocked the Tay idea on the head with the F100?
Hi Chugalug2,
You may well be right, at one point, and I did say "finally". I see the Djibouti photo shows evidence of the hideous hush-kit. [Could anyone ever detect any reduction in the noise as perceived by the human ear?]
Remembering the chronology is so often the problem, isn't it? The 146 was originally DH146, then HS146 (Hawker Siddley, for the uninitiated); so not sure BAC would have wanted to defer to it at that stage. Later on, it certainly rings a bell.
Not sure the MD80 series is a valid analogy for the BAC 2-11 and 3-11 proposals, though. The Spey got up to about 12,000lbs thrust. Wasn't the 2-11 going to use 2 tail-mounted engines of about 40,000-lb thrust; possibly RB211s? Even if not, I'm fairly confident that the 3-11 was of comparable size and configuration to the later A300, which started off with CF6s of about 50,000lbs. By that time, the RB211 had run into its carbon-blade debacle, which had delayed and crippled the L-1011 Tristar; and bankrupted RR.
[Apologies to Qu'est-ce-qu'il-dit and the moderators for the (further) thread drift.]
You may well be right, at one point, and I did say "finally". I see the Djibouti photo shows evidence of the hideous hush-kit. [Could anyone ever detect any reduction in the noise as perceived by the human ear?]
Remembering the chronology is so often the problem, isn't it? The 146 was originally DH146, then HS146 (Hawker Siddley, for the uninitiated); so not sure BAC would have wanted to defer to it at that stage. Later on, it certainly rings a bell.
Not sure the MD80 series is a valid analogy for the BAC 2-11 and 3-11 proposals, though. The Spey got up to about 12,000lbs thrust. Wasn't the 2-11 going to use 2 tail-mounted engines of about 40,000-lb thrust; possibly RB211s? Even if not, I'm fairly confident that the 3-11 was of comparable size and configuration to the later A300, which started off with CF6s of about 50,000lbs. By that time, the RB211 had run into its carbon-blade debacle, which had delayed and crippled the L-1011 Tristar; and bankrupted RR.
[Apologies to Qu'est-ce-qu'il-dit and the moderators for the (further) thread drift.]
BAC 1-11 electrical system was designed be a chap called David Jones (so he told me) at Weybridge. I think it was the first airliner with "Split Bus" 3 phase system which most types have followed since. Previous types had parallel systems where all generators fed the same main busbar.
When I was an apprentice at Hurn (69-73) various developments of the 1-11 were proposed including the -700 with "Re-Fanned" Spey (later Tay)
with seats upto about 140, the -800 with GE engine with seats upto 160, and the X-11 which would have had a six abreast cabin and seats for about 180.
The BAC 3-11 would have been about the size of the Airbus A310 with mixed class seating for about 180, and all tourist for about 250.
It was to have had RR RB211-22's initially, the same as the Tristar, to cut development costs. Stretched versions were on the drawing board.
As stated above the Concord was sucking all development money and even though the 3-11 had letters of intent from 4 airlines including American and Braniff and would have been in service a year or two before the A300, it was scrapped.
Another missed British oppertunity.
As an aside, the only good thing about this is that the 3-11 was to be 2 crew from the start and if it had been built there might be a lot of them as freighters now instead of A300's and I might not have a job as Flight Engineer.
Happy days.
When I was an apprentice at Hurn (69-73) various developments of the 1-11 were proposed including the -700 with "Re-Fanned" Spey (later Tay)
with seats upto about 140, the -800 with GE engine with seats upto 160, and the X-11 which would have had a six abreast cabin and seats for about 180.
The BAC 3-11 would have been about the size of the Airbus A310 with mixed class seating for about 180, and all tourist for about 250.
It was to have had RR RB211-22's initially, the same as the Tristar, to cut development costs. Stretched versions were on the drawing board.
As stated above the Concord was sucking all development money and even though the 3-11 had letters of intent from 4 airlines including American and Braniff and would have been in service a year or two before the A300, it was scrapped.
Another missed British oppertunity.
As an aside, the only good thing about this is that the 3-11 was to be 2 crew from the start and if it had been built there might be a lot of them as freighters now instead of A300's and I might not have a job as Flight Engineer.
Happy days.
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I think it was the first airliner with "Split Bus" 3 phase system which most types have followed since. Previous types had parallel systems where all generators fed the same main busbar.
Several each, DC & AC.
Quite reliable, too.
Happy days indeed, but for all the bright ideas that never came to fruition.
You two have got me thinking. What I remember about the Seven-oh was that the F/E used to have to do something clever with the AC generators before each one could be introduced on to the buses. I think they had to be synchronised. This was, thank goodness, quite unnecessary (or done automatically?) on the engineer-less One-Eleven. As far as I can remember, the F/E had no such task on the VC10 either.
Going to have to ransack the garage again. Watch this space...
You two have got me thinking. What I remember about the Seven-oh was that the F/E used to have to do something clever with the AC generators before each one could be introduced on to the buses. I think they had to be synchronised. This was, thank goodness, quite unnecessary (or done automatically?) on the engineer-less One-Eleven. As far as I can remember, the F/E had no such task on the VC10 either.
Going to have to ransack the garage again. Watch this space...
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How much info do you need?
Here's a small taster...
AC Generation and Distribution
The three generators are driven at a governed speed which ensures a nominal 400 Hz output. During normal operation, the main generators supply power to their respective AC main busbars (Nos.1 and 2) through associated circuit breakers (GCBs).
Each main AC busbar supplies its own distribution system. If one generator becomes inoperative or disconnected from its busbar, both busbars are automatically connected together by a split system breaker (SSB), and one generator supplies both No.1 and No.2 busbars. If the APU is running, the SSB remains open and the APU generator automatically substitutes for the offline generator through an associated GCB (No.1A or No.2A). If the APU is started after a main generator failure, the SSB is automatically opened before the APU generator comes on-line. Fault protection facilities protect each channel from the following faults:
The fault protection circuits automatically disconnect the respective generator from its busbar by opening the associated GCB when any, or a combination of any, of faults 1 to 5 are sensed. If an overcurrent fault is sensed by No.1 or No.2 generator, the alternative generator is prevented from taking over the defective busbar by automatic locking-out of the SSB. In addition, the accompanying under-voltage and/or under-frequency fault opens the associated GCB. In the case of the APU generator, No.1A or No.2A GCB will close, and on sensing the fault both GCBs will trip automatically.
For under-frequency/over-frequency and under-voltage faults, without overcurrent, a generator will automatically come on-line when the fault clears.
The under-frequency and under-voltage conditions automatically effect generator disconnection from its busbar during engine shutdown.
To reinstate a generator after over-voltage, stability protection, differential protection or over-current faults, it is necessary to select RESET on an associated generator control (GEN) switch. A selection of TRIP, on the generator control switch, disconnects the associated generator from its busbar. A reset selection is then necessary to reinstate the generator.
Amber generator failure (GEN FAIL) warning lights (one for each generator) give a visible indication when the associated generator is disconnected from its busbar, but the supply circuit of the APU GEN FAIL warning light is so arranged that an APU generator failure will not be indicated when both main generators are on-line.
A red BUS FAIL warning light is provided for each AC main busbar to provide a visible warning if the associated busbar voltage falls below a pre-determined value. The lights are connected to the master warning system.
KVA meters (one for each generator) indicate the total power supplied by the associated generator, and a frequency/voltage selector switch with five positions (EXT, GEN 1, APU GEN, GEN 2 and ESS) is provided to monitor the selected supply.
I have more if you need it.
TCF
Here's a small taster...
AC Generation and Distribution
The three generators are driven at a governed speed which ensures a nominal 400 Hz output. During normal operation, the main generators supply power to their respective AC main busbars (Nos.1 and 2) through associated circuit breakers (GCBs).
Each main AC busbar supplies its own distribution system. If one generator becomes inoperative or disconnected from its busbar, both busbars are automatically connected together by a split system breaker (SSB), and one generator supplies both No.1 and No.2 busbars. If the APU is running, the SSB remains open and the APU generator automatically substitutes for the offline generator through an associated GCB (No.1A or No.2A). If the APU is started after a main generator failure, the SSB is automatically opened before the APU generator comes on-line. Fault protection facilities protect each channel from the following faults:
- Over-voltage
- Voltage instability (stability protection)
- Differential current faults (differential protection)
- Under/Over-frequency
- Under-voltage
- Over-current
The fault protection circuits automatically disconnect the respective generator from its busbar by opening the associated GCB when any, or a combination of any, of faults 1 to 5 are sensed. If an overcurrent fault is sensed by No.1 or No.2 generator, the alternative generator is prevented from taking over the defective busbar by automatic locking-out of the SSB. In addition, the accompanying under-voltage and/or under-frequency fault opens the associated GCB. In the case of the APU generator, No.1A or No.2A GCB will close, and on sensing the fault both GCBs will trip automatically.
For under-frequency/over-frequency and under-voltage faults, without overcurrent, a generator will automatically come on-line when the fault clears.
The under-frequency and under-voltage conditions automatically effect generator disconnection from its busbar during engine shutdown.
To reinstate a generator after over-voltage, stability protection, differential protection or over-current faults, it is necessary to select RESET on an associated generator control (GEN) switch. A selection of TRIP, on the generator control switch, disconnects the associated generator from its busbar. A reset selection is then necessary to reinstate the generator.
Amber generator failure (GEN FAIL) warning lights (one for each generator) give a visible indication when the associated generator is disconnected from its busbar, but the supply circuit of the APU GEN FAIL warning light is so arranged that an APU generator failure will not be indicated when both main generators are on-line.
A red BUS FAIL warning light is provided for each AC main busbar to provide a visible warning if the associated busbar voltage falls below a pre-determined value. The lights are connected to the master warning system.
KVA meters (one for each generator) indicate the total power supplied by the associated generator, and a frequency/voltage selector switch with five positions (EXT, GEN 1, APU GEN, GEN 2 and ESS) is provided to monitor the selected supply.
I have more if you need it.
TCF
TCF - nice concise description, I did 1-11 electrics in 1973 with a guy called Colin Webster in CWL, by the end of the course we had to draw the bus bar layout or fail ! I've been sat here for a couple of days trying to remember what the SSB was called ! thank you.
Chris - On the 707 and 727 the generators were connected in parallel onto the "Tie Bus" the F/E had to manually parallel the generators before connecting them to the tie bus, remember the pulsing neon lights ? The AC bus bars were then fed from sections of the tie bus and could be isolated by judicious use of the "bus tie breakers" under fault conditions normally perated in parallel however.
Never really had much to do with 747 classics but seem to recall they were similar except that the paralleling was automatic.
Chris - On the 707 and 727 the generators were connected in parallel onto the "Tie Bus" the F/E had to manually parallel the generators before connecting them to the tie bus, remember the pulsing neon lights ? The AC bus bars were then fed from sections of the tie bus and could be isolated by judicious use of the "bus tie breakers" under fault conditions normally perated in parallel however.
Never really had much to do with 747 classics but seem to recall they were similar except that the paralleling was automatic.
Wodrick beat me to it.. Was on the 70 in my early years and remember some of the lazy flight engineers used to disregard the flashing lights and just hold the GB switch up til they closed, not guilty of this habit though. Such memories (sorry for thread shift)
Thanks, TheChitterneFlyer and Wodrick,
That visit to the garage seems less urgent now. Your info backs up dixi188's point about the 2 AC Main Buses on the One-Eleven being separate and autonomous, except in the single genny case; very different from the 707. From what I remember, it was a very nice system that even we pilots could get our heads round - and rather like the A320.
If memory serves, you can also isolate the AC generator field windings with a GCR switch (?) and, of course, disconnect the generator's CSD (constant-speed drive). The latter is actually a CSD-S, doubling as an engine starter (using air from the APU or an external air truck, just like aircraft today) The CSD-S is connected to the N2 (HP) accessory gearbox of the Spey engine by a somewhat fragile shaft. During engine start, this is what produces the classic shriek, its pitch rising with N2 rpm, until the starter dog(?) disengages at a certain rpm. At this point, there is often a momentary hesitation in the scream before it mercifully dies away. [Particularly welcome if you are having to stand under the engine to hold the start (air) valve open manually, in the event of a faulty solenoid.]
For the uninitiated, it is the CSD that controls the generator speed (regardless of engine N2 rpm); hopefully giving a steady 400Hz for the AC electrical system. This is the note (pitch) of the hum you are constantly aware of in an airliner cockpit. One of these days I’ll find out what note it equates to on a musical scale, but it is slightly below (flatter than) the “A” that an orchestra tunes to. If the note falls in pitch (i.e., below 400Hz), one of your gennies may be about to drop off line.
As for the B707, maybe 411A didn't recall the fact that − unlike the One-Eleven − the BTBs are closed in normal operation, effectively de-segregating the different parts of the AC system into a big daisy chain. After my post late last night, disjointed bits of it - including those flashing lights - were floating through my mind as I dozed off. The "enj" certainly works for his keep. The Seven-oh has so many other evolved idiosyncrasies for the successors of Wodrick and NG Kaptain to play with, including splitting the inner and outer flaps electrically to cope with a jammed-stabiliser landing. Phew! Don't the VC10 F/Es have it easy by comparison? [Can't comment on the A300.]
That visit to the garage seems less urgent now. Your info backs up dixi188's point about the 2 AC Main Buses on the One-Eleven being separate and autonomous, except in the single genny case; very different from the 707. From what I remember, it was a very nice system that even we pilots could get our heads round - and rather like the A320.
If memory serves, you can also isolate the AC generator field windings with a GCR switch (?) and, of course, disconnect the generator's CSD (constant-speed drive). The latter is actually a CSD-S, doubling as an engine starter (using air from the APU or an external air truck, just like aircraft today) The CSD-S is connected to the N2 (HP) accessory gearbox of the Spey engine by a somewhat fragile shaft. During engine start, this is what produces the classic shriek, its pitch rising with N2 rpm, until the starter dog(?) disengages at a certain rpm. At this point, there is often a momentary hesitation in the scream before it mercifully dies away. [Particularly welcome if you are having to stand under the engine to hold the start (air) valve open manually, in the event of a faulty solenoid.]
For the uninitiated, it is the CSD that controls the generator speed (regardless of engine N2 rpm); hopefully giving a steady 400Hz for the AC electrical system. This is the note (pitch) of the hum you are constantly aware of in an airliner cockpit. One of these days I’ll find out what note it equates to on a musical scale, but it is slightly below (flatter than) the “A” that an orchestra tunes to. If the note falls in pitch (i.e., below 400Hz), one of your gennies may be about to drop off line.
As for the B707, maybe 411A didn't recall the fact that − unlike the One-Eleven − the BTBs are closed in normal operation, effectively de-segregating the different parts of the AC system into a big daisy chain. After my post late last night, disjointed bits of it - including those flashing lights - were floating through my mind as I dozed off. The "enj" certainly works for his keep. The Seven-oh has so many other evolved idiosyncrasies for the successors of Wodrick and NG Kaptain to play with, including splitting the inner and outer flaps electrically to cope with a jammed-stabiliser landing. Phew! Don't the VC10 F/Es have it easy by comparison? [Can't comment on the A300.]