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We are used to seeing lots of screens in the front offices of airliners, but the road to get there involved several steps, one of which had a distinct VC10 connection. Using information from several 1970s/1980s articles and additional insights provided by Alan Teeder, the article below shows how a 1970s project led the way to the glass cockpit of today. Integrating instruments In 1971 the British government sponsored some studies to look into integrated avionics. Up to that point, flight decks had been designed for multiple crew members, including flight engineers, navigators and radio operators next to the pilots, but things were changing. Both the Dassault Mercure and the BAC 1-11 had been designed with two-crew flight decks so that they could be operated by just two pilots, even though not every airline used this option. The challenge here had been to fit all the dedicated dials and switches into the available space so that both crewmembers could operate the primary controls, manage the navigation systems and monitor and control all the aircraft systems.
The idea behind the project was to look into using CRT displays to integrate various instruments. The technology for this was available and parts had been used in previous years on creating ever more complex Head Up Displays in different military aircraft, but the next step was moving this across to the civil world. Together with Marconi-Elliot, BAC was awarded a contract to investigate an Electronic Attitude Display Indicator (EADI) and Electronic Horizontal Situation Indicator (EHSI) on the Concorde flight simulator, and this work later merged with studies undertaken by Hawker Siddeley Aviation (HSA) together with Smiths Industries. The BAC/HSA Advanced Flight Deck In 1975, the project moved towards what would be called the Advanced Flight Deck (AFD), when BAC and HSA formed a four-man group to look into both the human factors and the engineering side of creating an electronic display for basic instruments, navigation and systems, and integrating this into one flight deck design. The project had to create a working simulation of a complete flight deck to assess things like the general acceptance of CRTs, the eye strain associated with using them, night lighting considerations, but also technology and installation studies, display formats, reversion to traditional instruments and several other issues. Starting in 1976, this AFD prototype was set up in the Systems Simulation Laboratory in Weybridge using the following major elements:
Apart from using a VC10 centre console, the aircraft that was modeled in the phase I flight deck was based on the VC10 so that a complete audit of every control and display could be carried out. The VC10 was selected as it was an in-service type and therefore fully-defined, it was a three-crew aircraft and therefore suited a redesign to two-crew operation, and as a four-engined aircraft with the associated system complexity, the demands from using this setup in a two- or three-engined type should be less. With some minor exceptions, all the controls and displays from the VC10 flight deck were reproduced in the AFD prototype and the aerodynamics, engine and systems simulation modeled the workings of a VC10.
The end result of this was a two-crew layout that was revolutionary for 1976 but looks decidedly dated now. It used two CRTs for each pilot's flying instruments and navigation, three CRTs to display engine and system information and two extra CRTs to show checklists for a total of nine monochromatic screens.
The resulting layout was extremely promising, although the human factors assessment had not been completed by 1978. The setup used a display switching panel that will seem somewhat familiar to Airbus drivers, allowing the selection of individual systems or engines on the three centre displays. The flight displays were separate from this group of displays so that particular information was limited to a particular display location, thereby making certification and fault analysis easier. The flight displays could be changed to show various navigation formats while the primary instruments were always available on the outside screen in a format that still reflected the traditional 'steam gauges'. The three systems displays would normally show the engine data on the top display, with the other two in standby mode, available to automatically show system status initiated by the Master Warning System, or when manually selected. Initial results A group of eleven pilots nominated by BAC, HSA, the MoD, British Airways and CAA spent several days operating the AFD prototype, using predetermined exercises of approximately one hour duration, each spending some six working days in the simulator. Their feedback was generally favourable towards the concept. As this was just phase I of a larger project, the details from those assessments are not available unfortunately. Phase II was set in motion in 1977 by modifying the setup to match a 180/200 seat, short to medium range twin engined airliner with systems to match. Over time, this merged into using the A300 as a basis with the AFD simulating the dynamics and systems of this first Airbus type. Although the flight deck of the A300 as it was built did not feature the complete glass cockpit as we now know it, the ECAM system on the new airliner did incorporate the electronic checklists that were first trialed in the AFD simulation. The phase II flight deck was also evaluated by different groups of pilots in 1-day, 2-day or 5-day evaluation sessions. Overall, the evaluations totaled 1500 hours and the AFD had been used for 6518 hours by the time the project ended in november 1979.
The next steps After the initial stages of the project, work continued on colour coding and the next iteration of the AFD used colour CRTs. By 1980, the work done at Weybridge had led to RAE Bedford's 1-11 XX105 being modified with two CRTs in front of the left-hand seat. These were monochromatic screens initially, to aid troubleshooting, but were changed to colour CRTs in June 1981. The aims at this stage were threefold. First, lessons could be learned on integrating these systems into a flight deck. Secondly, a direct comparison would be available between the CRT on the left and the conventional instruments on the right. Thirdly, a flexible research facility would be available to complement other RAE projects. The display layout for the initial monochrome CRTs mirrored the format developed in the AFD. There was some criticism on the scan pattern required with the monochrome displays, as the heading information was only available on the navigation screen, making it somewhat difficult to incorporate this into the tight scan pattern available for the other parameters on the single screen. Because of this, the colour version was adapted to include a heading tape at the bottom of the attitude display, recreating the T-layout that pilots are familiar with. One of the suggestions that came out of this research was that strip scales might better fit the medium, and would be well suited to display airspeed, altitude and vertical speed. This was offered by pilots with previous experience with this type of display, perhaps from flying the EE Lightning with its horizontally arranged airspeed and Mach tape indicators. Although individual preferences over symbology could not be avoided, there was a lot of agreement on the useability of the colour displays and the associated benefits. Especially the addition of colour had reduced the workload in extracting information from the displays. It would not be long before the first completely electronic civil flight deck would be available on Airbus' A320 model, which first flew in 1987 and is still available in its A320neo version today.
With the project in an advanced stage, a display based on the AFD simulator was created for Farnborough and this was also used as a traveling 'exhibit' after the official research phases ended. As such, it traveled to other aircraft constructors to show the benefits of the technology. The display was based on cardboard panels and incorporated CRT displays linked to a VHS recorder, showing images recorded during a flight in the AFD simulator. As to where it ended up... I have found one rumour stating that the Smithsonian Museum had added this traveling version to its collection. Unfortunately, I have been unable to find anything about it on their website and my e-mail to their PR department has not been answered. I would have loved for one small part of the VC10 design to have ended up in this prestigious museum, even just a cardboard image of a VC10 part.
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