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How to weigh your aircraft  
and
get the data for your weight and balance form

   

This is a way to weigh your aircraft and prepare the weight and balance for an airplane or weight and loading for a PPC or WSC.  It isn’t the only way but is an industry accepted procedure and contains additional things that will be helpful for you later.

 

  1. Clean your plane and get as much dirt and debris out and off of it as possible.  Check all your baggage areas and saddle bags and remove all of the extra items that are not part of the empty weight. 
  2. Drain all the usable fuel from the fuel tank.  At this time you may want to decide where to mark any reserve fuel on your fuel gauge.
  3. Drain all the usable oil.  I suggest here you remove all but about a pint of oil from your oil tank.  Don’t drain it so as to uncover the outlet opening and get a bubble in the line.  Bad JUJU!  Remember when you refill your oil tank it would be a good time to mark it as to quantity.   So you could mark it every 16 ozs as you add oil or whatever you desire.
  4. Prepare an equipment list.  This is something new to most of you.  An equipment list tells anyone looking at the weight and loading or someone working on the aircraft or re-weighting it at a later time what the last weighing included.  For a Powered Parachute it would be something like:
    1. Equipment list for Six Chuter Legend  N1234  weighed 11-1-2006

                                                              i.      Six Chuter Legend XL Airframe

                                                            ii.      Rotax 582-99 with E-gearbox

                                                          iii.      64” PowerFin Prop

                                                           iv.      APCO 500 wing

                                                             v.      Odyssey PC625 Battery

                                                           vi.      [Other items such as smoke systems, etc.,  that are not removable]

For a WSC it might look like this:

  1. Equipment list for a Northwing Apache Classic

    1. Northwing Apache Classic Airframe

    2. Rotax 503 with B gearbox

    3. GPL starter

    4. 68" IVO prop

    5. 17.5 Mustang II wing

    6. Surestart battery

    7. 1050 BRS

    8. [Other item that are not removable, such as intercoms, radios, etc..

    An equipment list for and airplane would follow similar format. Just be sure to list to list everything that will be part of the empty weight.

  1. Find a place that is level under the landing gear.  For a tricycle gear if you have three scales place your aircraft on all three and calculate the weight.  If you only have one scale make two blocks of wood the same height as your one scale. Place two wheels on the wood and the scale under a wheel.  Record the weight and repeat for the other wheels.  For tail wheel aircraft you must raise the tailwheel to the proper attitude that the airplane will be in during flight when weighing that wheel.
  2. Now you will have to decide what your gross weight will be.  Most will simply use the maximum weight listed on the parachute label or wing specification label on their WSC wing.  For airplanes it might be the recommended weight of the manufacturer.   However if you are gravity challenged and need a higher gross weight to lift everything you want to lift,  you may add to the gross weight figure.  Remember that you must have flown the aircraft at the maximum weight in flight testing to use that weight.  To get the useful load subtract the empty weight from the maximum weight you decided to use.
  3. Now you will need to subtract the weight of the maximum amount of fuel and oil your tanks hold.  At 6 pounds per gallon for fuel if you have a 10 gallon tank that would be 60 pounds.  Oil is 8 pounds per gallon.  You need to know the correct capacity of your tanks for accurate weights. 
  4. What is left is the amount of weight of people and other items you may carry.  Subtract your weight and what is left over is the weight of passenger and any baggage you may carry. 
  5. If you have adjustable cg tubes you will have to look in the kit manufacturers manual to find out what weights each adjustment covers. For Weight Shift Control the Wing manufacturer should have given you a range you can move the hang point on the keel tube.  Most airplane mfgs. will have some type of weight and balance data in the manual.   
  6. Make sure you put the aircraft weighing job in the aircraft logbook.    The entry should be something like:   

 date      total time on aircraft       N-number

Aircraft weighed with tanks drained

Following equipment included:

Xxx

Xxx

Xxx

Xxx

Signed ___________

 

Now you have enough data to fill out a weight and loading form, one example of which is listed on the Airworthiness page.

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