Land Rover Forward Control 101.
The Land Rover Forward Control 101
(the 101 refers to the wheel base in inches)
was built to satisfy a British Army requirement for an air-transportable
heavy duty four wheel drive. Production ran from 1975 to 1978
although many vehicles were stored for long periods and others
were refurbished at later dates.
The solution to the Army's requirements was a unique Land Rover.
The drive-train came from the Range Rover of the day:
alloy 3.5L V8, LT95 transmission with 4-speed gearbox,
2-speed transfer case and full-time four wheel drive with
centre differential (and diff' lock).
Salisbury axles were fitted at both ends with 5.4:1 ratio differentials.
Suspension was by leaf springs
(it is not true that there was no suspension).
Tyres were 9.00x16" on 6.5x16" rims with a unique
six-stud pattern, bar treads being most commonly fitted.
The only way to achieve the required payload within the weight
limit was to adopt a forward control (FC) or cab-over design.
The chassis was new to the 101 unlike the earlier
(civilian) series IIA and series IIB
forward controls Land Rovers
that had shared the standard long wheel-base chassis and had ended
up far too heavy and under powered as a result.
Most of what little bodywork there was could be quickly removed
for air transport, in particular for lifting by helicopter.
The standard 101 is a soft-top although radio vans
and ambulances came later.
The radio vehicles had 24-volt electrical systems.
Many 101s were built as left hand drive models
for British commitments to NATO in Europe and elsewhere.
The 101's appearance can best be described as ugly-pretty.
There was no concession to styling and precious little to driver comfort.
Unfortunately the thing was just too basic to consider offering it to
the public as it was, although most have in fact been sold
to private buyers by the military.
Many vehicles were fitted with a side mounted
Nokken winch.
This winch is mounted on the outside of the left hand side chassis rail.
It is driven from the transfer case by a power take off (PTO)
mounted under the transfer case which leaves the standard PTO
on the rear face of the transfer case free for other purposes (see below).
The winch is actually a capstan winch of an unusual kind.
The wire rope can be run forwards or backwards through pulleys
that allow for an angled pull.
Coming into the winch, the wire takes a couple of turns around the
driven capstan.
It then passes to the take-up spool just forward of the capstan.
The take-up spool is chain-driven at a slightly higher speed than the capstan
during winching in operations - by a friction drive.
This maintains tension on the rope.
The tension is adjusted by a nut, a spring and thrust washers on the
take-up spool shaft.
As mentioned,
the rope can be run out of the front or rear (left) of the vehicle
but the drive wheels can only assist the winch in self-recovery
when it is run forwards: if reverse gear is engaged the winch
spools out (unless it is rethreaded which is a non-trivial operation).
The "normal" PTO on the rear face of the transfer case can
be used with a
special PTO
unit which operates at the same speed as
the transmission output shafts, regardless of whether hi-range
or lo-range is engaged.
The transfer case intermediate shaft is equi-distant from the
transfer case input and output shafts.
The special PTO unit takes its drive by a gear from the intermediate
shaft, in fact from the constant-mesh lo-ratio output gear,
and not from the transfer case input shaft with which it is co-axial.
The arrangement means that the PTO and the transfer case
output shafts rotate at the same speed under all conditions.
This cunning system made a
powered trailer possible
without the need for a second transfer case for the trailer itself.
There were numerous experiments with powered trailers in the 1960s
as detailed in the books by Robson and by the Slavins and Mackie.
An unpowered trailer is a real anchor on a four wheel drive off-road.
Drive can easily be taken from the PTO to the trailer
but the difficulties are to give it lo and hi ratio
in synchronisation with the vehicle, and
to provide sufficient articulation at the trailer coupling.
The 101 solution was impressive.
The special PTO solved the dual range problem.
The drive was then taken to the centre of the rear chassis
cross-member on the 101 where a very special trailer
coupling was mounted.
The coupling provided 360 degrees of freedom in roll,
ie. the trailer or vehicle could be rolled independently
of each other without damage to the coupling.
It also provided considerable freedom in pitch and yaw
(one film of army proving trials quotes 50 degrees),
ie. the unit could be jack-knifed.
For some reason the powered trailers were not put into production,
only a small number of prototypes being built.
Slavin and Mackie indicate that a possible reason was the trailer's
ability to push the 101 over in a jack-knife:
the trailer can exert a strong push at the height of the rear chassis
cross-member and rolls did occur.
The special PTO did however come in useful again with the
six wheel drive (6x6)
Perentie:
the drive was taken from the PTO over axle number two to axle number three.
The 101 was also sold to the Australian Army.
Military vehicles were sold off to the general public
as they came to the end of their working lives in the 1980s.
The British Army replaced its FC101s with the 4x4 Pinzgauer
by Steyr Daimler Puch.
Many private 101s have had diesel engines of various kinds
fitted; it is relatively easy to raise the gear ratios
by changing the hi-ratio gears in the LT95 transmission
or by substituting 4.7:1 differentials in the axles.
An overdrive is also available for the LT95.
Some 101s have had large capacity American V8s installed for
more spectacular performance.
Ambulance 101s are popular for camper conversions.
Several 101s starred
in the 1995 Sylvester Stallone movie
Judge Dredd,
forming the basis for the film's futuristic taxis (pictured).
From time to time one sees original Australian 101s advertised for 13K to 16K.
An attempt was made to derive a civilised forward control from the
Land Rover FC101, resulting in the
Llama project,
complete with coil spring suspension.
Preproduction models were built but it was killed off at the eleventh hour.
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Land Rover FC101 Specifications 1975-1978
- forward control, 2-seats 2-doors
- loa: 4290mm, width: 1830mm, height: 2180mm
grnd clearance: 254mm (diffs)
- approach: 60, departure: 45
- turning radius: 7.15m
- 3.5L petrol V8
- transmission: LT95, 4m, 2-speed transfer-case centre diff'
- suspension: beam-leaf/beam-leaf, brakes: drum/drum
(transmission hand-brake)
- tyres: 9.00x16
- Optional winch
See also:
Thanks to Rod Genn, Mike Ford, L.A11ison, Tony Luckwill, and
the Royal Australian Corps of Transport Museum
for providing background information.