Make a phone call to the people who pump out your Septic System. They can fill you in for what you CAN and CANNOT do. Also what NOT to flush into the System.
You have Bacteria in your Septic that digest the solids. You never want to kill them off if you are adding chemical to your Septic System from an outside source.
We had a Three Stage, 1250 gallon System with a large field for the Septic Field that needed to be mowed. This was on the Front Range of Colorado. The soil was good for Septic and a water well was 484 feet below the surface. I have to say it tasted better than a local Beer from Golden, Colorado. Cold and no mineral taste.
If you put toilet paper, solids and liquids into your Black Tank... you are not adding enough water from your Airstream Black Tank, that a home toilet dispenses after each flush. Just keep that in mind. The Septic People will give you all the information you want. You can also Dump at their Septic Disposal Site...
If your Black Water contains NO toilet paper or solids... go for it. Otherwise you need to consult the people who inspected your Septic for the House Closing.
Under Colorado Law, or at least where we lived, we had to pump the Septic Out when a home changes hands. Protects the NEW Homeowner. Some people on Septic do not operate their system like I would. It is a disaster and someone, YOU, will find out sooner than later.
Dumping toilet paper is the worse thing you can do. It floats like an Island in the Septic with the Solids on top. Urine is Food for Plants. Had you bought our Home... you can see that I took good care of our System. Once you clog everything up it will be coming into your Basement.
When we had the Septic Tanks pumped... I stood there and watched. It did not NEED to be pumped, as the Bacteria were having a 'great time'.
The larger the home bathroom count, the larger the Septic System. Our home had five Bedrooms with six Bathrooms. Also kitchen and garage sink water to add.
Five bedrooms have a much larger Septic System and Field, than a two Bedroom... as an example.
If you use toilet paper in your Airstream... don't. If you do, then you will learn not to. Many do not care. If things go wrong for them, they will pay through the you know what.