gearbox development was with the Scale Type gearbox. The
gearbox has had some considerable development and flying
(240hrs) in what is now our scale LAMA. Our production 'Scale'
Type Gearboxes are considerably changed from the early development.
early gearbox was lubricated from a remote oil tank, with
oil pumped to the box by a 'perry' pump that needed priming
prior to each flight... 'air pressure' was also taken from
the turbine casing to assist with lubrication to the bearings.
This system was a 'total loss' oil system... which has now
been superceded by wet sump lubrication from oil contained
in the gearbox casing. Now also, a Ceramic bearing at the
PT end of the input shaft is lubricated by a feed line with
Turbine Fuel/Lube mix. This is the additional 'Lube Tube'
or 'Manifold' found on the gearboxes.
'90' Type Gearboxes (90 degree) were developed in 2002 for
pod-&-boom use in the early Robbe Cuatro conversion.
Initial lubrication was by grease in the box to lubricate
gears and bearings... but this is not very successful. The
first batch of parts for production gearboxes were manufactured
in early 2003 with revisions in April 2004. The new (rev.2)
casing was developed in late 2004, and after testing was
introduced into production in August 2005 as the 'Red Top'
casing. Changes were made to internals which also fit in
the earlier (rev.1) silver/grey casings.
'90' Box has been developed with a wet sump and high temp
gear oil sourced from motorsport work with CASTROL. With
a gearbox system correctly manufactured there is no problem
using oil lube for the main gearbox. The PT end Ceramic
bearing is still lubricated by Turbine Fuel/Lube mix. Changing
Turbo-Prop gearbox has now completed development testing
and will be available for April 2011 in Helicopter format.
With the same basic gearbox as a prop drive for fixed wing
aircraft... currently flying in a Turbo Raven.
Specialist gear parts and the new casings are produced in
specialist engineering centres, and we no longer use model
helicopter related machining centres as we needed to improve
on component quality and integrity of confidentiality!