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Dynamic Propeller Balancing-

You wouldn't think of buying a new eight hundred dollar set of tires for you sports car and then pull out of the garage without having them professionally balanced first, would you?. The propeller on your aircraft weighs as much or more than a car tire and can produce much higher vibration levels which is directly mounted to your engine. So why settle on your aircraft?  Propellers that are "Dynamically Balanced" have four important benefits.

Increased Safety
Balancing your propeller reduces stress and fatigue to your engine and airframe. Vibrations over time can lead to failure of engines and airframes in catastrophic proportions. A Dynamic Propeller Balance can isolate and correct these destructive vibrations.

Improved Comfort
Continuous vibration for extended periods of time can cause fatigue to the human body.  Fatigue can affect both pilot and passenger.  With a "Dynamic Propeller Balance" you have reduced vibrations and lower levels of fatigue. In turn this allows greater concentration on piloting the aircraft and less motion sickness for your more sensitive passengers.

 
Improved Aircraft Reliability
Out of balance propeller/drive train vibrations effect a wide range of aircraft systems.
  • Avionics; radio and indicator failure
  • Alternator or generator failure, attachment bracket cracks, thrown drive belts
  • Vacuum pump failure
  • Wiring harness failure, chaffing, terminal end work hardening failure
  • Fuel control failure
  • Leaky oil coolers, cracked weldement areas
  • Cracked or broken exhaust components, heat muffs
  • Cracked or broken carburetor air box
  • Baffle, cowl and sheet metal cracks
  • Broken or cracked engine/turbocharger mounts
  Something to contemplate is that studies performed by the U.S. Navy indicated that a "Dynamic Propeller Balance" when performed on their turboprop aircraft resulted in a 100% increase in TBO of reduction gear boxes.      

Reduced Maintenance Costs
A "Dynamically Balanced Propeller" provides a smoother operating system with less vibration.  Consider how much you have spent repairing engine baffles, gyro instrument, cowling, alternator brackets, spinner support bulkheads or the frequency you change light bulbs. All this and more can be damaged by vibration
and that's "Not Just A Positive Spin!!!"





 FAQ: DYNAMIC PROPELLER BALANCING


What is Dynamic Propeller Balancing?
Dynamic Propeller Balancing is the process of utilizing an electronic balance computer to measure the amount of mass imbalance and in turn vibration produced by the aircraft's powerplant  and propeller.  Small balance weights are added to the propeller spinner or crankshaft to bring the mass imbalance back into into acceptable limits to reduce the vibration.



My aircraft runs fine.  Why should I have the propeller balanced?
The average aircraft that has not had a Dynamic Propeller Balance has an average imbalance of .45 inches per second velocity  (IPS).  This level is considered 4 times higher than what is an acceptable vibration limit of .10 IPS.  This vibration transfers energy into bearing surfaces causing friction.  Friction in an engine equates to a loss in horse power and thrust.  Your particular aircraft may have significantly higher or lower amounts of vibration compared to the average.  Only a professional with the appropriate equipment is able to make this analysis and it can't be accomplished "by feel".  Normally, by the time the human body can start to feel the effect of a vibration at 2300 rpm, the damage has long since started to take its toll on the engine and airframe.  Turbo Props require this procedure and even some piston engine aircraft to remain airworthy. For example, this is the case in the early model Bonanza which requires a "Dynamic Propeller Balance" to remain airworthy as ordered by an FAA Airworthiness Directive!


My constant speed propeller is new or overhauled and was balanced then.  Do I really need it balanced again?
Manufactures and overhaul shops perform a "static balance" to the prop while it is not in motion.  Once this propeller is coupled with a powerplant it stands to have a high probability to be out of balance while in motion.  For constant speed propellers after the first 5-10 hours in operation after a new propeller is installed, maintenance is performed or an overhaul the blades will seat, grease will level and shims will wear in.  All these minute changes affect the balance.  Once this time period has lapsed a "Dynamic Propeller Balance" should be performed to ensure proper balance in all operating conditions.


When should I re-check my propeller's dynamic balance?
Any time the propeller is removed.  A shift in the mounting can cause an imbalance up to a .30-IPS.  This is even when the prop is "clocked" in the same position as it was when removed.  As well a "Dynamic Propeller Balance" should be performed any time a large nick is reworked.  Other than these two events it is recommend to have a "Dynamic Propeller Balance" each 500 hrs TIS.


I have a geared engine.  Do I need a dynamic balance?
Yes.  Geared engines need a "Dynamic Propeller Balance" even more so than direct drive engines.  You propeller mass is much greater than the mass of the reduction gearbox. This causes stresses to the gear box and crankshaft to be magnified.  Studies performed by the U.S. Navy indicated that a "Dynamic Propeller Balance", when performed on their turboprop aircraft, resulted in a 100% increase in TBO of reduction gear boxes.  


Rates

Vibration survey & Dynamic Propeller Balance for Single Engine $250.00
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Vibration survey & Dynamic Propeller Balance for Twin Engine $350.00
If you have any questions please do not hesitate to call or E-mail!!!
And remember we can provide on site services 
and offer discounts to club fly-ins!
1-(405)-613-4547               jason@ProAMMS.com
 
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