I too would like to hear from Ted on the Tucker more. Especially since adding lead to the CG was essentially like dialing out flap, my question would be if he had adjustables (to dial out flap) or taken a number 11 to the flaps, does he think the results would have been similar, better or worse? I realize in a classic design, you don't want to cut flaps, but I'm speaking strictly from a performance point of view.
EricV
Eric and Kim,
First of all, I chose Eric's post to reply to for no other reason than he asked some specific questions about the test and I wanted to be able to reference them while typing this response.
The Tucker experiment did bear directly on this subject as well as another facet that hasn't been addressed too much here, the Netzeband Wall business.
In direct response to Eric's questions about flaps, yes, the ratio was adjustable and that was, in fact the first change we made clear back when the airplane was brand new at whatever VSC that was. Trimming the flaps (as we did with Paul Ferrell's Cardinal for last year's Nats) would have been a part of the program as well except for the classic aspect of the thing. Even though the rules wouldn't disqualify a model in classic for such a change, it clearly isn't in the spirit of the event to "modernize", even as an experiment.
One thing that should be said right up front. My Tucker was under 40 oz when new and with a wing the size of this ship would have had plenty of lift available to fly stunt patterns without any flaps whatsoever (see Ringmasters with modern powerplants, Skyrays, ditto, and Jamieson Specials winning OTS and even a few classic events). It must always be remembered that the primary purpose of flaps on any airplane is to improve the lift coefficient for a given area and planform of wing. If the wing is c apable of producing the necessary lift to perform patterns as tight and small as the flyer is capable of doing, their use has to serve some purpose other than providing additional lift. Sound odd? All the lift you need is enough to support the airplane in the tightest corners you can fly repeatedly.
This concept is sort of at the heart of where Sparky and I part company on our demands for lighter airplanes. If we were all trying to fly AMA patterns at rule book sizes using skinny winged, unflapped, underpowered stunters like they did back in the late '40s I would be a lot more in sync with Sparky. The reality is we aren't doing that any more and there are other options available.
Sorry, getting carried away there. Back to the Tucker.
Yes, any means of reducing the unnecessary byproducts of the large flaps would have been beneficial. Less movement (done), less area (an even better approach if it weren't for the "classic" aspect. This is because: 1. cutting down the chord of the flaps would have simultaneously reduced the hinge loads and, therefore, the line tension necessary to deflect the flaps any amount, 2. in addition it would have reduced the total area of the wing and increased the aspect ratio both of which would have improved maneuverailty for a given input and, 3. would have increased the wing loading improving line tension and backing off the Netzeband wall a tiny bit); reducing them to partial span (maybe a better approach from the fidelity aspect) would also have been beneficial.
The additional weight approach was chosen for the obvious reason, to address the subject matter of this and other threads and the well documented differences of opinion on the subject. The one thing we were absolutely certain of was that the added weight would assist the problem with inconsistent bottoms because it would make control response more positive and thus the airplane response more predictable. The thing we hoped it would demonstrate was that performance capability would not be obviously negatively impacted.
To the best of our combined abilities (Brett and I took turns flying it and there were other "regulars" monitoring and commenting on the effect) the experiment more than satisfied our expectations.
The issue was addressed again when I took out the unflown Ruffy to VSC a couple years ago. I expected a similar response with this ship and purposely took it out for first flights with a one to one control set up and the tools to change the ratios. In this case your expectations were almost exclusively resolved by continually reducing the flap movement relative to the elevators. It eventually got reasonably well trimmed but never really reached what I would call a competitive sort of response. I felt the shortcomings with this ship were the verysmall stab/elevator and the low aspect ratio wing. It needed to have the CG further forward than I would personally desire (to retain stability at the end of the flight when the tank was empty) and the resulting higher drag in corner loaded the engine excessively in the high density altitude at Tucson. It's better here in San Fran but still not a favorite.
In direct answer to your question, in my opinion my Tucker was a more competitive airpalne at the higher wing loading. If I could have reduced flap travel more it would have certainly been "better" but I don't feel the confidence gained from the more positive feel at the handle would have been achieved by doing so.
I more or less keep pounding the same old saw I started with many years ago. I think lift produced should balance lift necessary with only a reasonable margin of excess to cover poor density altitude situations. When lift is well matched to what is needed the airplane's CG will appear to track the radius of the corners flown and any discussion of "dropping the tail" or "turning around a point behind the wing" etc. will disappear.
Once that part of the equation is solved you simply need enough power to insure that the airplane will not lose significant airspeed during maneuvers (because lift goes up as the square of airspeed). IMHO, lift beyond that requires serves only to complicate the trim issues and bring the Netzeband wall closer rather than further away (because you are deflecting controls further than necessary which required increasingly more line tension the further you have to deflect them).
Good questions. Hope I didn't go too far afield.
Ted
Topic: I see some people are not brain dead (Read 10571 times)
