Multiple Weights and Balances for Your Aircraft
By Jason Blair, ATP, CFI-I, MEI-I, FAA Designated Pilot Examiner, AGI
April 2019
Every aircraft can carry as many 200-pound people as there are seats in the aircraft, right? Oh, and certainly doing so with full fuel wouldn't be a challenge, correct? I think you know that the answer to these questions is not affirmative.
In general aviation aircraft, we regularly have to trade fuel onboard, and therefore, range, for extra people, baggage, or other weighted items. It’s just part of the game. But for pilots who have more seats than they regularly use, want more baggage area, or have seats that aren’t really sized to accommodate adults well, removing some seats may be a desirable option.
Removing that third row of little seats in the back of your Cessna 210, the seat next to the door in your Baron or Cessna 340, or the back seats in your Piper Cherokee 140 offers pilots a couple things. First, it can offer more space for baggage or just easier access to the cabin area of the aircraft. Second, it will give back a little bit of weight-hauling capacity when a seat or multiple seats are removed. It may not be a lot, but it may be one extra bag for that camping trip.
Keep in mind that to remove a seat and operate your aircraft properly in compliance with regulations does mean you have to do something else. You will need a weight and balance that you will carry on the aircraft that will represent the current configuration of the aircraft. It’s no different than when you have new avionics, or an extra fuel tank installed. You are changing the configuration of the aircraft from its original state and the weight and balance must represent how the aircraft will be operated.
This doesn’t mean that if you remove a seat or two you can never put them back in. Nor does it mean you can’t put them in and out as needed.
Many aircraft owners have chosen to have more than one weight and balance document certified by a qualified maintenance provider for their aircraft. This allows them to operate the aircraft in multiple configurations with a weight and balance document that will correctly reflect the Center of Gravity (CG) position and overall empty weight of the aircraft. They can then determine what else they can put in the aircraft before reaching a maximum gross operating weight limit while staying within the CG limitations of their aircraft operating envelope.
If we consider an owner of a Cessna 206 who typically flies only with the pilot and one passenger, they may choose to remove the rear four seats in the aircraft. If we assume each seat weighs 30 lbs, that could translate into an additional 120 lbs that could be used for fuel or baggage.
I regularly fly a Cessna 340 for a friend who has decided to remove the “sixth” seat by the door to help make entry into the cabin easier. Another friend flies a Beechcraft Baron in which he has done the same. Yet another has a Cessna 207 that I can honestly say I’ve never seen with the back seats in! He has an alternate weight and balance and loves the extra space for bicycles he and his wife transport on their flying adventures.
So now a question. Is it necessary for a mechanic to remove and replace seats every time I want to do this? Fortunately, no.
You will, however, need a maintenance professional to certify an alternate weight and balance document first.
But once that is in place, and if you configure the seating of the aircraft in accordance with each weight and balance you have developed, you can do this as a pilot/owner under the FAA preventative maintenance regulations.
Does this mean that you should just grab your tools from the garage and start taking things apart if you don’t know how seats are removed from your aircraft? Well, I wouldn’t recommend that, but if you got a little instruction from your local mechanic, it is probably something you could easily do on your own.
So, there is nothing wrong with having multiple weights and balances for an aircraft. I know many operators who have weights and balances that represent their aircraft in multiple configurations. And multiple configurations may make your plane more suitable for a wider variety of missions such as camping, bicycles, transporting shelter animals, or possibly longer distance between fuel stops.
We’d love to know what you think of this PIREP. Please email us at [email protected] and let us know.
To sign up for our monthly Avemco PIREP series,
click here.
Reprint by permission only. If you would like to obtain reprint requirements and
request permission, please email us at [email protected]
Jason Blair is an active single- and multi-engine instructor and an FAA Designated Pilot Examiner with over 5,000 hours total time and over 3,000 hours instruction given and has flown over 100 different makes and models of general aviation aircraft. In his role as Examiner, over 1,500 pilot certificates have been issued. He currently works for, and in the past, worked for multiple aviation associations that promote training and general aviation. He also consults on aviation training and regulatory efforts for the general aviation industry. Jason Blair has published works in many aviation publications, a full listing of which can be found at www.jasonblair.net .
|