I beg to differ. Whilst a loop could JUST be flown within 4g, it leaves absolutely no margin for error.
4.4G, but I disagree. A competent aerobatic pilot could fly 1000 out of a 1000 loops with no more than 3G on the meter. They could fly 1000/1000 aileron rolls under 2G. Competent aerobatic pilots don't NEED much margin with the basic maneuvers. Pilots who are first learning? Of course they do. They also need an instructor sitting with them.
Saying 4.4G gives you "absolutely no margin for error" is like telling a licensed pilot that a 1.3Vso approach gives you "absolutely no margin for error". I would no more tell an inexperienced aerobatic pilot to jump in an RV-9 (or any aerobatic airplane) and have them go do some aeros than I'd tell someone who has never flown an airplane to go take the airplane up...and be sure to fly a 1.3Vso approach for sufficient "safety margin".
I was a flying instructor in the RAF and I can tell you that both these can go horribly wrong, very quickly if you fail to get the nose high enough in the first half.
No kidding. You're talking about pilots experiencing aerobatics for the first time. I'm not. And instructors can also tell you how beginning PPL students will spin airplanes during basic stall practice and come close to stalling on base-to-final...and a million more shenanigans that happen when you are first learning. I fail to understand how this comment relates to aerobatics in "non-aerobatic" airplanes. Anyone with the ability to screw up the basics this badly will not be protected by an additional 1.6G of load limit. They are at the beginner level, and they need to be in an aerobatic airplane with an instructor.
Doing aerobatics in a non-approved aircraft goes into the same category as flying in cloud without an IR, unauthorized "fly-bys" and any other number of rule-breaking acts which display poor judgment and lack of professionalism even if they could be considered "safe".
I'm not arguing that. I'm not arguing legality. I'm purely talking aerobatics. Legality vs. safety issues are two different things.
I might agree with this statement, but I have removed:By definition, and accident records, it is not safe - not least because any pilot doing it on their own accord is unprofessional, probably acting illegally and hence by definition is "unsafe".
Any pilot doing aerobatics without training "on their own accord" in any airplane is unsafe. I am not talking about these types of pilots. I'm talking about pilots with enough experience, basic skill, and smarts to make perfectly acceptable decisions on their own. And yes, it CAN easily be done safely and consistently by an experienced pilot.
And before anyone thinks I am advocating we should forget about design intent, I am not doing that. None of this is a recommendation for anyone doing acro in a plane not designed for it. In reality, the RV-9 is little different from the countless other airplanes "not designed for aerobatics" in which pilots consistently and safely do loops and rolls in. And regarding airshow pilots, most people (with little or no acro experience) seem to give them worship status. Let me break it to you, to get an ACE card to begin flying air shows only takes very minimal aerobatic skills that anyone with some very basic training already has. "Airshow pilots" are no more special in the skill, judgment, and ability department than the many other aerobatic pilots out there who don't care about flying air shows.
So let me repeat -
Don't teach yourself aerobatics (in any airplane) - especially an RV-9.
Get aerobatic instruction in something other than an RV-9.
Afterwards, do NOT build your basic aerobatic skills in an RV-9.
Understand an RV-9 is stressed to 4.4 not 6.
If you question your skills and wisdom of doing acro in an RV-9, it is unwise.
Don't be stupid.
If you are a skilled aerobatic pilot and do an aileron roll in an RV-9, well that's your choice. We even have some of these pilots here on VAF.
They're more likely to kill themselves turning base to final. There's not much margin remember.