Konrad
Very Strong User
Wrong thread!
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Hill Hobbit
Very Strong User
You really do take exception to literally everything I post on Aloft Forums, don’t you Konrad?
You’ve said that my comments are from a smart ass, and asinine.
Just how far are you going to go, eh? I’ve got the real impression that you, and as far as I’m aware it’s only you, would like me gone from Aloft Forums.
You’ve said that my comments are from a smart ass, and asinine.
Just how far are you going to go, eh? I’ve got the real impression that you, and as far as I’m aware it’s only you, would like me gone from Aloft Forums.
Doc J
Very Strong User
Doc J
Very Strong User
Doc J
Very Strong User
Doc J
Very Strong User
Doc J
Very Strong User
Doc J
Very Strong User
Hill Hobbit
Very Strong User
Thing of two?
I much prefer Seven of Nine personally…
I much prefer Seven of Nine personally…
ORRich
Very Strong User
you're partially correct - the regular cargo is strapped down, but ornery, mis-behaved cargo get bolted down - esp with a knife edge in the flight plan -
Doc J
Very Strong User
Doc J
Very Strong User
Doc J
Very Strong User
No I didnt.
Konrad
Very Strong User
Well, well, I see that Mario Perner of CCM is contemplating enlarging the V-tail area on his Vantage.
Talking with some of the better pilots they have said they would like to back off on the aileron differential to gain some needed roll rate. (But doing so allows the nose to go somewhere other than where they want to go). With most, good, pilots being able to get their F3F ships into the 30's this means that laps are just turning competitions. I think in the future F3F ships will all have much larger rear vertical side area to allow the ailerons something to bite against.
In straight line speed the idea of minimum wetted area might have some merit. But as F3F is really a turning competition the control drag will over power any theoretical speed advantage from insufficient tail volume (minimum wetted area). (I think the Redshift designer had this idea about control drag, he just placed the added area on the wrong side of the fuselage) Of note is that the rear fuselage wetted area is dropping in favor of adding this wetted area on a longer moment arm (to the fins). The change in fuselage geometries is allowing for the smaller wetted rear fuselage area while keeping the boom stiff to deal with flight and landing loads.
It is good to see competent designers and pilots reassessing the F3F requirement, as the performance envelope evolves and making the appropriate changes. I see some real nice changes coming from designer that actually understand control and stability and the compromises that one must make to gain a great handling fast ship.
After I get my REDshift wrecks (gut piles) back into flying shape I'm actually going to make a set of fins that are about 30% larger than the OEM fins. This is in hopes that I can get a REDshift to perform, closer to the Freestyler while allowing the REDshift's wing to shine. Like I said earlier I think I've come to the limit for the flight improvements I can reach with just changing the V-tail junction.
Talking with some of the better pilots they have said they would like to back off on the aileron differential to gain some needed roll rate. (But doing so allows the nose to go somewhere other than where they want to go). With most, good, pilots being able to get their F3F ships into the 30's this means that laps are just turning competitions. I think in the future F3F ships will all have much larger rear vertical side area to allow the ailerons something to bite against.
In straight line speed the idea of minimum wetted area might have some merit. But as F3F is really a turning competition the control drag will over power any theoretical speed advantage from insufficient tail volume (minimum wetted area). (I think the Redshift designer had this idea about control drag, he just placed the added area on the wrong side of the fuselage) Of note is that the rear fuselage wetted area is dropping in favor of adding this wetted area on a longer moment arm (to the fins). The change in fuselage geometries is allowing for the smaller wetted rear fuselage area while keeping the boom stiff to deal with flight and landing loads.
It is good to see competent designers and pilots reassessing the F3F requirement, as the performance envelope evolves and making the appropriate changes. I see some real nice changes coming from designer that actually understand control and stability and the compromises that one must make to gain a great handling fast ship.
After I get my REDshift wrecks (gut piles) back into flying shape I'm actually going to make a set of fins that are about 30% larger than the OEM fins. This is in hopes that I can get a REDshift to perform, closer to the Freestyler while allowing the REDshift's wing to shine. Like I said earlier I think I've come to the limit for the flight improvements I can reach with just changing the V-tail junction.
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purview
Very Strong User
watch you
Konrad
Very Strong User
Don't hold your breath. I have to first bring the gut piles back to flying condition. Then continue with the control and stability studies as they pertain to the limitation of the Redshift..watch you
Just taking a close look at my wings I see that I have close to 2.5:1 mechanical aileron differential. This could limit the amount of aileron correction I could practically gain with the added tail volume from the larger V-tails. Not sure I want to rework the servo installation to allow for large control deflections (roll rate) while maintaining a less aggressive aileron differential (more down aileron motion). But as I'm seeing some issues with the Servorahmen and the HS08 splines I might actually have the opportunity to reconfigure the linkages.
But at some point I must realize that there will be diminishing returns trying to make a silk purse out of a sow's ear. I will be reworking these REDshifts at least until my new F3F racers land at my door step. And then I may keep a hand in this project just to see if I can actually get the much needed stability even with the Durante nose. The 96° V-tail and excessive aileron differential does now allow for the poorly designed REDshift to actually run an F3F course (not competitively) with some speed and controllability. Still nothing like the Freestyler-5
Again these are for ships in my hands. Between the Redshift and Freestyler-5, the Freestyler-5 is the superior ship at my skill level. Heck all the fast boys are using Freestyler 5's & 6's. Now I know of nobody that was given the opportunity to champion a REDshift actually take on the REDshift as their F3F tool of choice. I now know why!
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Doc J
Very Strong User
Konrad
Very Strong User
Say what? That looks to have a rather large tail volume. Without knowing the spec's it looks to have adequate tail volume to counter the destabilizing effect of the nose. This is some of what tail volume is doing. The nose is a necessary evil, when it come to stability. This is why it is kept as small as possible to allow the tail a chance to control the airframe.
Doc, this doesn't look like one of your designs. Heck, I even like the tail. I see a minimum wetted side area on the tail boom (low drag) with of these drag credits added to the V-tail volume. This might be something to look at with your new Spada design. I see you warned us that the tail in the CAD renderings of your design looks bigger than it actually is. With your history this doesn't add confidence in the new design's directional stability.
The issue here with the Redshift is that the nose is too large by design to counter the crabbing seen on the cliff face. The result is the added area ahead of the fuselage center of pressure was not taken into account when the nose moment was lengthened. The result is a tail volume that is shy resulting in directional stability issues. In the thread where someone is holding court it is clear that the stability and control are not fully understood. Area ahead of the fuselage center of pressure is a destabilizing feature and MUST be adequately addressed by the tail volume. As I recall it was stated in that thread that the fuselage side area a head of the center of pressure does not cause any destabilizing effects. This is blatantly false. I point to the USA flight test pilot training manual, also it was mentioned that the forward side area can be used to trim for spiral instability.
It is clear that the REDshift is suffering from inadequate tail volume as the ailerons need an exorbitance amount of differential and one needs to add a lot of provers rudder mixing to keep the nose on point when making high rate rolls. These corrective action have a high cost in added drag!
We see this not only in the flying qualities of the REDshift. But if looking at just the front and rear side area (volume) of the Freestyler and redshift we see that the REDshift has 27% more volume ahead of the center of gravity and 27% less tail volume than the Freestyler. Ok, the stability isn't as bad as this would suggest as the Redshift has less wing area and cord.
It is clear that the REDshift is lacking much directional stability. And from the discussions in this thread it is understood why, the designer doesn't full appreciate the destabilizing characteristics of the added frontal side area with regard to directional stability.
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