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Flitzer plans comprise 33 mostly A1 size sheets, and are
comprehensively illustrated, with much text, and many
perspective, exploded views of components.

All metal fittings are drawn full size, and plans have been
updated to reduce time and cost of fabrication.

Since first flight, the 1834cc VW-powered prototype Flitzer

Z-1 has flown over 70 hrs., without any changes to rigging or
trim of the machine, other than for experimental purposes.
Handling is exemplary, controls being light and powerful,
without the over-sensitivity associated with some small
biplanes. The aeroplane has been dived to over 125 mph.,
controls firming-up appropriately, without any aerodynamic
buzz, and terminal velocity appears to be well short of the
flutter regime. It flies hands-off in the cruise (Vc = 86 mph.)
and will complete a 360 deg. turn in 7 secs. at this speed.

At Vc, deliberate displacements in pitch, both positive &
negative, result in stick-free re-acquisition of flightpath in

1/2 oscillation, ie. deadbeat damped in cruising flight.

With the American Ellison EFS-2 slide carburettor, developed
power is in the order of 60+ hp., and the aeroplane gets
airborne in 7 seconds in about 130 yds. At approx. 80%
MAUW., rate of climb averages 700 fpm., and maximum
speed straight-&-level is just over 90 mph. with the currently
un-refined 'cruise' propeller, at 3000 rpm., red line being
3300 rpm. for this engine, so more performance may be
achieved via propeller improvement.

Stalls are innocuous, with or without power: 44 mph. straight
ahead power off, and below 30 mph. IAS at full power - with
gentle wing drop and plenty of pre-stall warning in terms of
hunting in pitch and short-period wing rock. Control about
the yaw and roll axes is maintained below stall. Recovery
is immediate on relaxation of stick pressure. The true stall
would not develop with the Z-1 prototype's "small tail", the
aircraft mushing in stable sink at an indicated 44 mph.,
power off (a safe condition). But with the 6% area increase
in the horizontal tail, as shown on the Z-21 "plans" version, a
clean g-break is now achievable, and with full power the
'straight' , unaccelerated stall occurs at an angle of +35
degrees of pitch.

Best angle of climb is achieved at 45 mph. IAS, and best
ROC at 60 mph. Approaches are flown at 60 mph.,
reducing to 55-50 over the hedge, touching down at about
45. The latter figures may be reduced with the slightly
larger tailplane shown on the plans. The machine copes
well with crosswinds on a narrow farm strip, despite not
being equipped with brakes or a steerable tailwheel,
although these options will be included on a later sheet.
Streamlined main undercarriage leg fairings have been
fitted, and add both to the machine's appearance, and also
to performance.

Some fifty sets of Flitzer drawings are in circulation world-
wide, with several examples being built in the USA, as
well as in Australia, NZ, Italy, France, Germany, Canada, S.
Ireland, and the UK. The second Flitzer, the ex-Bell-
Aeromarine proof-of-plans Z-21A demonstrator flew in '99,
and handled beautifully, approaches with the larger tail
confirming the predicted reduction of some 5 mph in IAS
by comparison with the prototype Z-1, the latter a/c having
previously been tested with a facsimile Z-21 tail. The Z-21A
is specifically identified by its 2" wider fuselage (24"
cockpit width compared with 22" on the prototype and
basic Z-21)

Maximum weight authorised is 750 lbs., and structural
improvements, higher tailplane reserve factors, and the
use of 4130 steel on the plans versions, have contributed to
an increased overall reserve factor at this weight.

Empty weight is 479 lbs., and fuel tank capacity is 8.5 gals.
(Imperial). The aeroplane is comfortable to fly, and the
cockpit is surprisingly warm and free from draughts,
despite the small 'period' aeroscreen. The growl from the
paired exhaust pipes is a sound quite unlike the typical VW
'flutter' , more like a 'twenties long-stroke V-type. The
machine never fails to attract attention wherever it is seen,
and has been flown by several eminent test pilots.

Plans are extremely detailed and graphic containing all
information needed, down to options on engine
installations, exhausts and induction pipe offsets to provide
the aerodynamically cleanest and most attractive engine
cowling, as well as they're being a build manual.

Section profile is USA35B, with excellent L/D and gentle
stalling characteristics.