Interestingly if you talk to *experienced* aerobatic pilots they will suggest that the crash was not caused by the overweight condition or C of G. Overloading an aircraft, putting the C of G too far rearward won't necessarily result in this outcome.
With all due respect I would suggest VH-XXX that either you misunderstood the "experienced aerobatic pilots" or they are talking through their collective hats and need more experience. The RV4 is designed to the aerobatic limits of +6/-3 at a weight of 1375 pounds. Go one pound over that 1375 and you are no longer flying an aerobatic aircraft because the g limit it is able to sustain is less than the mandated. To be more than 22% overweight and have the CofG nearly 4 inches outside the aft limit and not expect a sad outcome is a little optimistic to say the least. The RV has had fatal spin accidents in the past with some one in the back seat - an aft CofG tends to flatten the spin, and knowledgeable RV pilots are aware and abide by the limits. They are there for a reason and once you go outside them you become your own test pilot.
What the manufacturer has to say about spinning the RV4
Spin tests of the prototype RV4 were performed up to the limit load (1375 lbs. Aerobatic gross) and CG (27% aft of leading edge) with satisfactory recoveries being easily affected. With the CG more forward and power at idle, the RV-4 would not remain in a spin for more than about two turns, even with full pro spin control input. With the CG aft it could be held in a spin but would recover as soon as the controls were returned to neutral. Inverted spins were not tested since the prototype RV-4 was not equipped for inverted fight. In general the RV-4 spins nose low and has very positive spin recovery qualities.
Even though the prototype has good spin recovery characteristics, each airplane is unique and should be individually tested. Small variations can have surprisingly large affects on spin and spin recovery characteristics. This is particularly true of any additional surfaces forward of the aircraft CG. For example, spin recovery was better when the landing gear leg fairings were removed. They reduce directional stability. Vans Aircraft does not consider spins to be a recreational aerobatic manoeuvre, and does not recommend they be casually undertaken in the RV-4. My bolding.
From an RV4 flight manual
Because of the range between VNE and VA the RV-4 is more susceptible to pilot induced overstresses than most contemporary aerobatic aeroplanes. Cruise speeds are often well above VA. THEREFORE, THE PILOT CAN EASILY IMPOSE DESTRUCTIVE LOADS ON THE AIRFRAME at speeds ABOVE THE RELATIVELY LOW MANOEUVRING SPEED. NOTE LIMITATIONS, EXERCISE CAUTION AND FLY ACCORDINGLY.”
If the CG is too far aft, longitudinal stability is reduced leading to inadvertent stalls and spins; spin recovery maybe difficult or impossible with the CG aft of approved limits.My bolding
All you can do is get the message out there
