Mainly the FPS max of 26 or 30 for
both you and lead. For close formation, your airplane starts clipping with theirs and the view changes, that can be found
here called "Wing Clip Fix."
There are also tips found in T-45 training manuals (from flight school). Here's a little section from the formation FTI:
2. Keys to Successful Formation Flying
a. Relax, using a light touch on the aircraft controls – easy to say, but hard to do. By
relaxing, you will be amazed at the ease of flying formation.
b. Keep the aircraft trimmed.
c. Scan the lead's entire aircraft, and don't fixate on any one gouge or aspect of the lead
aircraft.
d. For every correction, apply a corresponding re-correction. For example, if you are
sucked and add power, you will reduce power approaching the position, and then
slightly increase power to stabilize.
e. Have fun. If you're not, you're not doing it right.
Safe formation flight requires control of direction and rate of relative motion between aircraft.
Because the lead is considered to be fixed, he is the primary reference for attitude control. Any
movement between aircraft involves the wingman as he moves around the three axes of the lead's
aircraft. You can control relative motion through anyone axis or a combination of all three
axes.
All of these manuals can be found
here for public download. My Firefox reports a problem with the connection, but just add the exception and it goes right through. Another note for the website is things are labeled as FTI and Lecture Guide. The FTI is a "Flight Training Instruction" and the "Lecture Guide" is something (AFAIK) that an instructor would read in the classroom.
