On the other hand....have you ever seriously reviewed the stress issues?
Dan,
When do we expect these stops to come under stress? Only 2 conditions I can imagine are at full deflection either by pilot input or in the case of an unrestricted/unrestrained rudder being blown by the wind. Of these 2 which one are we most concerned with? I believe I have read of rudders being bent by the wind when a rudder gust lock was employed.
Dave
I should hopefully see very infrequent full rudder deflection, as was demonstrated to me in my transition training in Vernonia, since brakes are used so often in ground steering, and full deflection on short final indicates the landing is likely beyond my capability this early on. Later, who knows.
I am one of those who query this "modification" for stress reasons.
In answer to
When do we expect these stops to come under stress? Only 2 conditions I can imagine are at full deflection either by pilot input or in the case of an unrestricted/unrestrained rudder being blown by the wind
I am not really concerned with either. They will not kill you, and most likely, if any damage were to result, visible on a walkround check, and just cost ??? (or $$$!) / time.
My concern is a 3rd condition - a (presumably) inadvertant tailslide. This, to me, is the ultimate "stress" for a Rudder Stop (and Elevator). It takes a scr*wed up aerobatic manouevure,
and a mishandled recovery... however, I have seen both together, both by me
and more frequently, students... If you have not done a tailslide, please let me assure you the control forces as they reverse are harsh, and if you fail to hold them, a real hard/fast application of full rudder / elevator
The problem in the RV case is that if the "modified" rudder stop fails (in fact, I doubt it will be the stop that fails, it will be the rudder) what now stops it? Well, the elevator, and rudder jammed into elevator only equals one outcome
So to me it is a risk benefit analysis. The "benefit" is a slightly more sexy looking rudder stop. The risk? Death to both occupants probably.
So to
but I've never heard of any actual problems or data to support their findings
I am glad you have heard of no problems... just when/if we do, they are likely to be major. As for data - surely it is not us that have to provide the data? Van's provides the design, presumably to an accepted protocol / design standard. It is surely up to those who choose to override this should provide the data to "prove" their alternative is equally, or more, safe than the Van's design?
Please do not get me wrong. Anybody who chooses to modify their design
at their risk I am fine with - we all take risk/benefit decisions every day. My concern is with those who encourage others, without expressing all the facts, to modify the Van's design, and even make $$ out of it. Go back to the original RV-3 design issues and fatalities, and the RV-8 prototype accident... In my interpretation, Van's design in both cases was proved correct, but not far off optimal
Andy
RV-8 G-HILZ