The Huntwing BMW Trike.
The
Huntwing has been available as a plans built trike since 1992, although the
original Huntwing flew as early as 1982. The design was refined and proven to
section S in 1992 and consequently over 100 sets of plans have been sold, so
far about 20 have been completed. It remains the only approved set of plans for
a weightshift microlight, I believe in the world but certainly in the UK.
At
the time that the plans were completed it was thought that the design would
appeal only to those working to a tight budget and show the engine mounts for a
Fuji Robin 440 engine, cheap and readily available at the time. Subsequently an
engine mounting plate was included for the Rotax 503 and this has been the
favourite option of all the engines.
There
are also Huntwings with the Rotax 447 (a little lacking in performance), all
versions of the 503, Rotax 462 and Rotax 582.
The
first question that most people ask are "Can we use a 4 stroke?" and
often this is followed up by references to the BMW engine, or sometimes the VW.
So far no one has used either the Jabiru (which is probably just as well) or
the 912 Rotax which would be very good.
The
BMW engine is very good in a Motorbike but there are lots of modifications
required to fit into an aircraft and it is heavy that so until the introduction
of version 2 of section S (which allows the pilot to trade fuel against pilots
weight) it was not really a goer.
In
1998 I completed the construction of BMW powered trike but it is only now after
completing 300hours of flying with a modified BMW engine, 200 hrs on a Huntwing
and some 100hours on a Blade wing that
I have enough information and the drawings to offer this conversion to others
with some confidence that the engine is better than a Rotax 2 stroke and
cheaper to run.
Initially
a completely new trike was built and fitted to G-MMGT the original Huntwing.
Following
structural loading tests, noise testing and flight testing was completed
successfully and a full Permit to Fly was issued.
The
aircraft was flown to Blois in 1999, the Pyrenees and Blois for a second time
in 2000 and after some 200 hours of flying the wing was changed for a production
Blade wing.
Again
a full test program was implemented for this new combination and eventually
this received a full Permit to Fly in mid 2001.
This
combination has now 100 hours completed including a trip to Beas de Segura in
the south of Spain, 2 up and with full camping equipment, in June 2001.
Further
details of this trip can be found on www.wyevalleyflyers.org.uk
complete with some pictures.
The
Mainair Blade has a top speed approx 10 to 15MPH faster than the Huntwing and a
cruise speed approx 5 to 10 MPH greater. It is slightly lighter in pitch, has a
good speed trimming device, is slightly heavier in roll than the Huntwing and
has a slightly slower stall speed. Overall therefore it has a better speed
range and can be purchased straight from Mainair without the hassle of
building.
Are
there plans for the Huntwing and the Blade BMW?
A
set of plans have now been completed, along with complete instructions on the
modifications required to the engine and these are available at a cost of £40.
The
trike plans will be available as a standalone package, both in there original
format at a cost of £60 or complete with the BMW plans at £90. This package
includes details of the engine mounting frames and also details of the use of
the Pegasus Quantum/Quasar tank. If it is intended to use the Blade wing an
additional £15 will purchase the owners manual for this combination.
The
original Huntwing plans are £125 or £160 with the BMW plans attached.
You
now can build a complete Huntwing with any of the current Rotax 2 strokes and
several older versions.
You
can use the BMW R100RS engine on the Huntwing.
You
can just use the Huntwing Trike with the Mainair
Blade, which save the effort of building the wing.
These
are available from
John
Hunt,
Old
Railway Inn,
Clydach
sth,
Nr
Abergavenny.
Gwent.
NP7
0RD
01873
830876 (evenings)
07768
131349 (Mobile)
Checkout
the website for more information
www.huntwing.co.uk or e-mail me on john.hunt@huntwing.co.uk