
MT PROPELLER
(Fixed and Variable-Pitch)
Background
Gerd Muhlbauer has been a leading light in
the German propeller business for many years, and was the Technical Chief of
Hoffman Propeller before setting up his own business some 16 years ago. This has
expanded very successfully, and the company now produces a huge range of
propellers for almost all applications, both for fixed and variable-pitch.
MT propellers are effectively the only
choice for unlimited level aerobatic aircraft, which is probably the hardest and
most demanding application for any propeller. Indeed in every World and European
Aerobatic Championship since 1998 every competitor was flying with an MTV variable-pitch
propeller!
Applications
MT propellers are available for most
aircraft – whether ‘Experimental,’ or for fully certified aircraft. They
have a number of intrinsic advantages over other propellers (see over), but in
particular are able to give significantly quieter aircraft – this is becoming
increasingly important, as well as enhanced performance.
Construction
MTV propellers are of a new design,
incorporating the latest lightweight hubs, while the blades are manufactured
from compressed laminated wood, covered with composite and a steel leading-edge
strip. This combination is considerably lighter than conventional metal
propellers, and brings with it a wide range of additional advantages.
Advantages
The advantages of the MTV propeller are
many, but include:
- A wide range of propellers are
available, and where quietness is sought, there is the ability to go from
two to three blade or three to four blade propellers, without compromising
performance, but providing a significantly quieter propeller.
- The wood/composite design of the MT
propeller is a superb absorber of vibration, and, particularly, when coupled
with dynamic-balancing, almost all aircraft are significantly
smoother in operation. For example the Piper Malibu has always had problems
with cracked super-charger fixtures, and this problem has totally
disappeared with MTV propellers. About 400 Malibu’s (of
some 800 in service) are now fitted with MTV propellers.
- The advanced blade design typically
means that performance for take-off and climb is increased, while cruising
speed is certainly the equivalent of other propellers, but typically one or
two knots more.
- The vibration damping qualities of the
propeller is such that the engines typically do not have any RPM ranges to
avoid, and the propellers are far kinder to engines, thus enhancing engine
life, as well as protecting airframe and airframe components.
- The propeller has a stainless steel
leading-edge, which is harder than aluminium. If it is damaged it can be
replaced an infinite number of times. On the other hand, with aluminium
blades, although the leading-edge can be ground, after four to six times,
the blade will then be below minimum dimensions and has to be discarded.
- In the case of a ground strike, if 75%
of the blade is unaffected, then the blade can be rebuilt, rather than being
damaged beyond repair. Also in the event of a major ground strike, the
chances of serious engine damage are far less with an MTV propeller than
with a metal one.
- For aerobatic use, MT propellers are
designed to change pitch quickly, which make them ideal in such
applications, but also MT aerobatic propellers work in a reverse sense,
meaning that should there be a failure of oil pressure to the propeller,
they will go into coarse-pitch, avoiding over-speeding the engine.
- MT propellers are remarkable value, and
typically significantly cheaper than conventional alternatives, while giving
supreme German technology and quality.
- Easier starting. Because the propeller
only has some 25% of the rotational inertia of the equivalent metal
propeller, it is much easier to turn and therefore engines start a great
deal more easily.
For further information in terms of
applications; technical issues – please contact us at our Head Office above.