EngineeringOily RagSwordfish

Swordfish W5856 Winter Maintenance Progress

By November 21, 2019 November 28th, 2019 No Comments

There is plenty of work around Swordfish W5856 as winter maintenance progresses. Many internal voids have been visually inspected with a borescope typically inserted into drain holes in flying surfaces and next week the wings will be folded for access into some remaining spaces.  Each main undercarriage element consists of 3 struts; the front radius arm is held to the fuselage by a spherical bearing and the rear inboard strut by a pivot bolt allowing the wheel to move out and upwards compressing the third ‘oleo’ strut.

This early oleo has a coil spring as the main shock absorber but is partially oil filled and on compression the oil is progressively restricted in moving between chambers within the strut and also on rebound to provide some damping. The oil contents will be checked via a fill and level plug

The 3 propeller blades have been removed from the hub so that the mating faces can be inspected visually and by NDT methods.  When reassembled there are stout gaskets between the propeller roots and hub to minimise corrosion.  The electrics bay is behind the rear cockpit and when the new 8.33Khz radios and PFLARM were fitted the old ‘breadboard’ was replaced with a nice new alloy base. This bay which also contains the voltage regulator is covered by a sliding plate beneath the gun and is not that weatherproof and a canvas cover is laced around the upper fuselage tubes to keep rain off the wiggly amps.  Rather than repair the old canvas again the team have decided to make a new one from strong waterproof canvas,  pictured below the old canvas is on top of the new one below being marked up for new eyelets.

The ancillaries on the back of the Pegasus engine have received plenty of attention.  Both magnetos have been bay serviced and replaced (photo) and also the engine starter unit that was beginning to show signs of reduced performance. In normal use the heavy starter internal flywheel is spun up to high speed by the ground crew operated crank handle, the pilot then engages the clutch drive to the crankshaft. Over a long period engine oil can leak into the starter and hinder its smooth operation.  The generator was also replaced and provided with a new drive shaft. The shaft has a flexible rubber and textile coupling at each end, though with the speeds involved the generator had to be carefully aligned and provided with a new distance piece under its mounting.  The engine inspection schedule requires 2 cylinders to be removed and it is pleasing to note that the pistons and rings are in good condition.