Precision Airplane Scale - New Weight and Balance for N601BD

Today I had my airplane weighed on a precision airplane scale that can register the weight of a dime. It was designed and constructed with a grant from the EAA years ago and is used by the CAFE Foundation. There is no charge, but a donation to the Foundation is suggested.

I did my original weight and balance in August 2008. After that my Zodiac XL was painted, I added sound proofing, and I recently replaced a 25 lbs. battery with a 13 lbs. battery. So a new W&B was needed and, today, I drained all my gas and emptied the airplane. Off to the scale.

The scale is awesome. All you do is roll your airplane onto it and get your weight. There are no ramps, or hoists, or anything else. Just role it on. It seems too easy. It took all of 3 minutes to level the airplane and the weight was given on the digital read out.

To my surprise the main gear weight was only one-half pound lighter than the weight I got from the bathroom scales when I did the original W & B. HOWEVER, the nose wheel weight was 49 lbs. off! I never felt really good about the nose wheel weight I got with the bathroom scale. I have always felt my airplane was nose heavy. Well, it is.

My original numbers August 8, 2008:

Right main: 250
Left main: 250
Nose wheel: 233

Total Weight: 733

New numbers September 7, 2009:

Right main: 249.5
Left main: 249.5
Nose Wheel: 282

Total Weight: 781

The good news is that I am a very conservative pilot. Reviewing the W&B calculations I used for all of my flights, I have been between 24% and 30% of MAC. With the new W&B I will always be in that range.

What makes my airplane so nose heavy? (especially with a light Jabiru pulling it?) I have a galvanized steel firewall. Many of the Zodiacs have an aluminum firewall. I makes for about a 15 lbs. difference forward of the datum point.

The other thing I noticed is that the paint added 60 lbs. to the overall weight. (Take 12 lbs. off the original 733 lbs. for the battery change out, and you get 781-721=60). We used a single coat primer and single coat Jetglo for base coat and accent stripes.

This scale is a great option for us on the left coast. Quick and dirty...very precise. With full fuel I know for sure I have 359 lbs. of payload (with a gross of 1320 lbs. - yeah, I know, the factory planes are down to 1255 lbs.)...two standard weight persons (170 lbs.) and 19 lbs. of baggage, tools, etc., in the wing lockers.

All things considered, this makes me feel a little better about a lot of things concerning this airplane.

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Comment by Terry Watson on July 10, 2019 at 3:56pm

Does anyone have a completed W&B they would be willing to share.  I am in the process of redoing mine and would love to see how it compares.

Comment by Craig Payne on September 17, 2009 at 5:40pm
"Many of the Zodiacs have an aluminum firewall"

Really, I've never heard of one from the factory. I've had two XL kits (one from 2002 and one from 2008) and both had galvanized firewalls.

-- Craig
Comment by Bob Simmons on September 9, 2009 at 10:59am
Not exactly the prime topic, but what soundproofing did you do?
Comment by Brad DeMeo on September 8, 2009 at 9:02am
Jake, you are correct. I did not take into account the before and after paint for the mains. The mains were probably much lighter without the paint. I think it's worth the $150 to know what you've got.
Comment by Jake Reyna on September 8, 2009 at 7:02am
Brad, I'm confused. If paint added 60 pounds, how can the main gear weights be lighter? Could it be that all of the scales were off originally? It's not easy finding information on paint weight, but what I did find led me to believe that paint added 25-30 pounds. Hopefully others will post their before and after paint numbers.

Did the original W&B include wheel pants?

I'll be weighing my airplane in the near future and have been debating whether to use bathroom scales or spend $150 to let the local A&P use his certified scales. You added the final straw and I will let the A&P do the initial W&B. I might not like the numbers, but they will be accurate.

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