Why do I
need a Top Prop conversion?
Top Prop conversions offer a number of benefits, depending on
the particular aircraft. These benefits can include improved ground clearance and rate of
climb, reduced noise and takeoff distance, longer overhaul intervals, elimination of
Airworthiness Directives, elimination of tachometer placards, a new propeller warranty,
and increased safety and improved appearance.Do I have to buy the kit from the Hartzell factory?
No. While Top Prop kits are sold through the Hartzell Service
Center, they are also available from most propeller shops and many fixed base operators.
Check with the facilities in your area.
How long does it take to get a Top
Prop?
The propeller kits are generally in stock and can usually be
shipped within a day or two of order.
Will I have to change my governor?
Generally, no. However there are some installations such as
early Cessna 180, 182 and Beech Bonanza models which do require a governor change. If a
governor change is required, the proper governors will be listed on the STC documents.
Do spinners come with the kits?
Yes, new spinner assemblies are included in all Top Prop kits.
The spinners are constructed of aluminum alloy which is polished to a mirror finish.
What is the warranty on a Top Prop
conversion?
Our Top Prop propellers and spinners are warranted against
defects in materials and workmanship for 1,000 hours or 3 years, which ever comes first.
We also offer a 10 flight hour / 90 day full refund period if you are dissatisfied with
the installation of the propeller on your aircraft.
Are Polished Blades
available?
No. Polishing the blades removes the protective paint and
anodize layer and encourages corrosion. The warranty is also voided.
What is the advantage of a scimitar
propeller?
These propellers are available for certain aircraft and use
blades that have thinner, swept tips to reduce noise.
What about noise reduction?
In general the three-blade propeller will be quieter due to
the lower tip speed (smaller diameter) and additional blade (higher blade passage
frequency which is more comfortable to the human ear). Most Top Prop STCs were approved on
a "no acoustical change basis" which means they are no louder than the original
installation, however noise levels for most applications have not been quantified since
this is not required in the US.
What is the recommended
time-between-overhaul
(TBO) of a Top Prop?
For propellers installed on piston aircraft it is 6 years or
2,400 flight hours, which ever comes first. Aluminum hub turbine TBO's are 6
years or 4,000 flight hours. Steel hub turbine TBO's are 5 years or 3,000
hours.
What kind of performance
improvements
can I expect from my Top Prop?
Since the Top Prop program currently covers over 120 different
types of aircraft, it is necessary to generalize a bit. When converting from a two-blade
propeller to a three-blade, takeoff and climb are generally improved while cruise speeds
remain about the same. Two-blade to two-blade conversions are generally made to replace
obsolete propellers, and performance would be unchanged across the flight envelope.
Can I just buy the STC paperwork
from
Hartzell and find my own used prop?
No, the STC document sets are not for sale. The Top Prop
program was set up to provide new manufacture propellers to the current aircraft fleet. |