To demonstrate the measures I have uncovered, I will use several aged Hammerhead paper airplanes to demonstrate various features that increase the abilities of aged airframes. The benefits of these features are not limited to the Hammerhead, but it is more versatile and able to have these add-ons applied with ease than several other aircraft. The add-ons are independent of one another, but incurring all 5 can be favorable for certain requirements.
Step 1: Materials
Aged Paper Airplane Airframe (Hammerhead airframes pictured)
Step 2: Un-taping, Unfolding, Refolding and Re-taping
2.) Once all of the tape is off, do the steps for constructing the aircraft in reverse (for the Hammerhead, go from Step 8 to Step 1). Once you've gotten it down to its sheet form, remake it back into its airplane form and tape it.
The objective of doing this to clear any debris out of the airframe that might have gotten lodged in it.
In some cases, this is the only step needed to bring an aircraft back up to the same standard as a new one.
Step 3: Flaps and Spoilerons
The objective of this is to increase the operational margin for the paper airplane between its VNE (Never Exceed Speed) and VSR (Stall Speed).
2.) To make spoilerons, you make small cuts in a surface above the wing. On the Hammerhead, the place for this is on the canards. Here you cut them about an inch across each. Then you fold and adjust them.
The objective of this is to give the plane a pitch-up attitude. With one spoileron deployed, it acts as the equivalent to an aileron (hence the name "spolieron"), rolling the aircraft.
Step 4: Slats and Making the Canards Polyhedral
The goal of making slats is to maintain a pitch-up attitude.
2.) Applying a polyhedral layout to the canards is a simple operation which increases stability in craft, old or new alike. To down this on any aircraft, simply modify the orientation of a part of a wing or control surface (in this case, canards). On the Hammerhead, fold the the canards so that the fronts are candid with their fronts and the bends are parallel with the fuselage.
The aim of this is to make rolls easier to recover from and avoid for longer distance flights. In a twist, they can also be made to help initiate rolls as well.