Servicios Aéreos, LLC

Do your passengers complain your plane is too uncomfortable?

Do you find yourself worn out after 2 hours in the cockpit?

Do you feel a continuous buzz in the rudder pedals?

Are your cowl fasteners working? Exhaust hangers cracking?

Do the flight instruments shake so that they are hard to read?

It could be that your propeller is out of balance! 😵

What is Dynamic Propeller Balancing?

Dynamic propeller balancing is a procedure for reducing the synchronous vibration of the engine/propeller combination, that is - the vibration at the propeller RPM. This is also called "1/rev" (one per rev) vibration.

An sensitive accelerometer is attached to the engine block near the front main bearing, and an small laser pickup is used to identify the passage of one prop blade, marked with a piece of highly reflective tape. The electronic balancer can then measure the magnitude of the vibration and the phase - the number of degrees of prop rotation between the measured vibration peak and the marked blade passage.

Balancing weights are then added to the prop/engine assembly to reduce the vibration to the lowest level practical. The mass and location of the weights is computed by the balancing software. The weights are typically added to the flywheel for Lycoming-type engines and to the spinner backplate for engines without a flywheel. Some propellers allow mounting of balancing weights directly to the prop hub.

The "factory standard" for most certified aircraft is 0.10 IPS RMS (inches/second, root mean squared). This is a statistical average vibration measure. We guarantee a final balance level of less than 0.07 IPS, but usually can get down into the 0.03-0.04 range, sometimes even better! 😎

The procedure requires a number of engine runs, typically 3 or 4, to allow the software to home in on the exactly correct mass and location for the balance weight. The first run measures the base vibration level and the second run is a good-guess test weight to establish the response characteristics. Then the 3rd and 4th runs will quickly get the vibration down to the desired level.

Why do you need a Dynamic Propeller Balance?

Say you just purchased 4 brand new premium tires for your Corvette for $400 each. Would you just mount them and drive away without having them balanced? After driving 20,000 miles on these tires, wouldn't you have them rotated and re-balanced?

The same applies to the prop on your plane! Even though the separate components might be carefully manufactured under close tolerances, and may even be statically balanced individually or as pairs, the full operating assembly still needs to be dynamically balanced. And like the tires, after flying for a few hundred hours, due to normal wear and tear on the prop and engine, you're likely to need to rebalance.

The operating speeds for aircraft propellers (35-45 Hz, equivalent to 2100-2700 RPM) are unfortunately outside the range that human beings can sense well. You can not accurately differentiate levels of vibration at those frequencies.

Compared to an unbalanced aircraft, a well-balanced system can have 10X-20X lower 😎 vibration levels. Greatly reduces wear and tear on engine, airframe and people. Vibration and sound levels are often reported in decibels (db), a logarithmic scale that more closely corresponds to how humans perceive sounds. The 10X factor is equivalent to 20db down!

Costs & Time?

These are the standard prices for balances done at FFZ:
Note: Prices were updated 1 Jan 25. Sorry.

Lycomings (& clones), not geared, normally aspirated: $175

Note: Lycoming-powered aircraft with restricted access to the flywheel, e.g. PA28's without a split nose bowl,
or with really difficult cowlings, e.g modern C182s with 5-piece upper cowlings, may have a $25 up-charge.

Continentals, or other engines without a front flywheel, not geared, normally aspirated: $225

CJ-6A with Housai or M-14, and Yaks with M-14: $225

Other engines, and/or geared, and/or turboed: by arrangement

These prices assume that you will help with decowling/recowling the aircraft, and that you will run the engine for the balancing iterations.
If the aircraft is already at Falcon and decowled for other maintenance, you can leave it that way and just taxi over.

There is $25 discount for EAA, RPA or AOPA members! 😎 We hope you'll support the people who support all of us! (Discounts do not stack, sorry.)

Typically, a balance for a Lycoming will take about 1.5-2 hours. Continentals, etc. take more time (and cost more)
because at the end of the procedure we need to remove the spinner, drill the spinner backplate for the permanent weight,
reinstall the spinner and re-check the balance.

There is a $30 call-out charge for balances done at CHD or DVT. For GEU or GYR, this fee is $50. We really prefer that you fly your plane over to FFZ for the balance. This fee may be split for multiple planes done consecutively at the same airport.

We accept cash, checks, credit cards, Venmo, PayPal or Zelle.

Note: We are happy to do certified aircraft, but we cannot provide a logbook entry or a 337.

Special cases:
If we cannot reach a final vibration level of <0.07 IPS RMS, you pay nothing!
If we set up the aircraft and the initial vibration level is below 0.10 IPS, you may opt out of the rest of the balance and only pay a $50 set-up charge.