… continued
C. Manufacture of the Leyland lynx / Bison at AEC
Following this proposal AEC would cease to manufacture the current range of Mercury and Marshal models. In their place AEC will manufacture vehicles which are identical, with the Leyland Lynx and Bison powered by the Leyland 500 engine. This proposal could be implemented quickly - in less than a year’s time (see Exhibit 2 - Timing Chart).
The benefits of this action are: -
- It will maximize the penetration of 500 engined vehicles as quickly as possible instead of slowly increasing at the expense of the AEC 505.
- It enables the supply to be maintained by transferring production between the two plants as the orders for the other vehicles produced change.
- As it is principally an assembly operation the production can be easily transferred back to Leyland when other AEC volume is large enough.
- It will extend to AEC the rationalization proposed between Leyland and Albion.
- The major engine components can be brought from Leyland where there is adequate capacity.
- The engine components for which Leyland have not got spare capacity can be produced on the AEC GP plant, thus minimizing capital expenditure and charges in the AEC overhead recovery.
- The 500 engines used by AEC could be assembled and tested at AEC as they will have spare capacity in these areas.
It is recommended that AEC stop production of the Monarch, Mercury, and Marshal and the 505 engine. Subject to the studies mentioned below they should be replaced by the 500 engined Lynx and Bison range.
Leyland Truck and Bus wishes to rationalize production, and thus increase it, by rationalization, around the Lynx and Bison range. To do this they should have the maximum sales orders for this type of vehicle. Sales of Lynx and Bison models are only rising slowly and large increases can only be expected by introduction of new models, and by substitution for other Divisional models.
New models (e.g. the turbo-charged models) are being introduced which will gain new business but only partially substitute for other heavy Divisional vehicles.
The Lynx and Bison ranges are fully inter-changeable for the Mercury and Marshal - both marques compete in the same market sector, but the Lynx has the better specification.However, Leyland can only take this volume if AEC can build other models in sufficient volume. (Mercury / Marshal approximately 3,000 units per annum).
If the Mercury and Marshal stay in production they will continue to sell to established customers and thus partially prevent the concentration on the Lynx / Bison range. Neither of these alternatives are satisfactory. In the former case AEC will not, for the next three years, have sufficient volume, even allowing for possible Guy production, to lose all medium truck production. Note from my source of this document. “Legendary loyalty to AEC products by customers who would not buy the Lynx and Bison whilst the Mercury and Marshal was still in production. The powers at Leyland realized this and wanted to stop production of Mercury and Marshal to boost sales of the unreliable Lynx / Bison models”.
In the latter case the substitution of the 500 for the 505 engine will be delayed, money will have to be spent on the 505 engine plant and Leyland will not be able to take excess volume of medium chassis from AEC.
Thus it is recommended that: -
a) The 505 engine and Mercury / Marshal are phased out of production.
b) They are replaced by the Lynx / Bison built at AEC (subject to the following studies).
c) AEC’s output of Lynx / Bison purposely restricted to keep an economic volume, but expansion should be restricted to the heavy goods range. AEC heavy goods vehicles should be offered in preference to Leyland Freightline HG vehicles which would then cease production.
d) AEC will also drop the Reliance coach in favour of the Leyland Leopard. The Leopard has had more development (questionable) and gives a greater profit. This change would give approximately 8 vehicles weekly to Leyland, an increase of 70% over the present Leopard production. (The Reliance was outselling the Leopard)
To maintain 760 engine volume the 510 engine should not be offered at AEC, except as an option in Guy 32 tonners, although the first option remains open.
As the 505 engine is phased out at AEC then manufacture of the 760 and V8.801 will become increasingly uneconomic as many machine tools are common to all engine production. If possible the complete manufacture of all these engines should be undertaken at Leyland, with the aid of machinery shipped from AEC where applicable.
Capacity Limitations on the Lynx / Bison
Capacity restrictions exist on production of units for this range. To substitute for the present Mercury / Marshal range 60 to 70 vehicles per week will be produced.
A) Engine
Whereas the capacity of the major units on the transfer lines is 600 p.w. capacity on GP machining, assembly, and test is severely limited and at the present time could not meet the extra demand. AEC would, of course, have some redundant plant following the demise of the 505. Therefore it is suggested that, as a general rule, AEC buy those components from Leyland that are manufactured on special purpose plant and and those piece parts which require jigs and fixtures for manufacture on GP plant, (assuming capacity is available). As Leyland increase the number of special purpose machines the AEC content should be progressively reduced.
AEC should assemble and test the engine until Leyland has sufficient capacity to carry out these functions.
B) Rear Axles
The Lynx and Bison are fitted with Albion and Maudslay hub reduction axles but the Mercury / Marshal are fitted with Maudslay Mk. 1 single / double reduction axles.
To avoid supply problems from Albion and a reduction in volume at Maudslay, it is suggested that solo and coupled Maudslay Mk.2 axles are engineered into the Lynx and Bison in such a manner as to be directly interchangeable with the hub reduction axles.
The other production problem concerns the bogie suspension for the 6-wheelers.
The Marshal is fitted with either the balance beam 4-spring underslung suspension, or the AEC ‘A’ Type 2-spring bogie. The present Bison is fitted with the AEC ‘A’ bogie but the new 24-tonne design is to have the 4-spring Albion suspension to allow an 18-ton bogie weight. It is suggested, for a first stage, that the AEC built Bison uses the Albion 4-spring suspension only. When the proposed rationalized 4-spring and FPT6 2-spring suspensions become available these will be used.
C) Front Axles
The Mk.2 Lynx and Bison - using the SC40 frame - use the 8 ft. wide Alford and Adler rationalized axle. However, the present Mercury / Marshal has the Maudslay L240 series axle - a copy of the present 7’ 6" Alford and Adler design. Maudslay hope to make this new, wider design but no decisions have been made on manufacturing location.
…to be continued
Did the Major have the larger engine then, Tilcon however would only ever have bought the cheapest most basic option of any truck though! 
