Design & Construction




The current post war Luton Minor LA4a is the redesign by Arthur Ord-Hume in conjunction with Latimer-Needham when they were Phoenix Aircraft Ltd. It is intended for the Aeronca JAP J.99 flat twin air-cooled engine developing a maximum of 37 HP. It is possible to fit other engines, for the airframe is stressed for power units up to 55 HP, and examples are flying with VW and Continental engines. This article relates to the Aeronca engined version.

It must also be stressed that it also relates to the two aircraft flown both of which have variations, not only from each other, but in minor details as well from the original plans. For example, though neither has it, the plans provide for a baggage space behind the pilotís seat.

Possibly the carriage of much baggage with only the 37 HP engine would have undesirable effects on rate of climb; but with the more powerful engine a reasonable amount of kit can easily be carried.

The design is intended for easiest possible construction by amateurs having limited space and limited workshop facilities. Thus the mainplane is in two halves, reducing the space required for construction: and metal fittings are all simple parts made from mild steel sheet. The fuselage is of box construction with spruce longerons and bracing and plywood covering, except for the top deck aft of the cockpit, which is fabric.

Wings have two spars, each comprising top and bottom spruce booms, with ply web. Ailerons hinge directly from the rear spar. The two halves of the mainplane are mated by fittings on two steel tube pylons over the cockpit, and braced by a pair of parallel streamline steel tube struts from each side of the fuselage.

The tail unit is of similar wooden construction. All covering is by fabric, except for the leading edge of the mainplane which is ply covered. The undercarriage is of steel tube using rubber in compression shock absorber struts. The LA4 may have either tailskid or tailwheel and heel brakes may be fitted to the mainwheels.