The Tubular Axle Induction Motor (Taim) was developed by R&DD in conjunction with GEC, in the late 70's and early 1980's.

The idea was based upon an 'inside out' induction motor with a wound stator inside an APT-E type tubular steel axle.

It appears that it generated a great deal of heat in operation and dispersion and cooling proved to be very difficult. Also it depended upon extreme and virtually unobtainable engineering tolerances in the environment in which it was working. The idea was eventually abandoned.

Here is an internal R & D document about T.a.i.m. with a picture and diagram. 


The article explains the background and operation of the hollow axle motor

Author's collection

Rear and more

Author's collection

On test

The two axles in the dynamometer rig in the Advanced Projects Lab at RTC

BR Official

Test rig Another shot of the axles

Author's collection

As part of the project a bogie equipped with two TAIMs was fitted to 920001, a three car unit made up from the remains of PEP stock and comprising RDB 975430, 975431 and 975432.

Lifting trailer car RDB975431 at the Mickleover test track whilst fitting a bogie equipped with two Taim units

Peter Keen collection

Closer view of the bogie being fitted

Peter Keen collection

As part of the project a half-scale model was constructed by BR graduate engineering management trainees as part of their attendance at Loughborough University. I am indebted to John Lindsay for the following photographs


A schematic drawing of TAIM Model A close up of the sectioned bearings on the model
Model The model was completely sectioned to show its construction and operation. Test rig The real thing on the test bed in the Advanced Projects Lab at RTC
The works The stators from TAIM    

Any more information or pictures of Taim would be gratefully received

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