Konrad
Very Strong User
You’d think!
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Doc James Hammond
Very Strong User
Ballast...a weighty problem.
Of course the concentrator problem becomes worse with the intrinsic mass of the ballast used...
Steel = 8.03 gm/cc
Brass = 8.4 gm/cc
Lead = 11.342 gm/cc
Tungsten = 19.23 gm/cc
Depleted Uranium = 19,050 gm/cc
Osmium = 22.6 gm/cc (Osmium is also the one of the world's most expensive rare metal at US$ 12.5 per gramme)
But in any case, whatever the ballast substrate, there is still a relatively large mass concentrated in a relatively small area in the highly dynamic environment of a model aeroplane.
Since therefore, the retaining system needs to be pretty sturdy, I suppose the best idea is to try to make the ballast tube 'concentrator' a) Part of, and contrbuting to the overall structural integrity of the model, whether its situated in the wings or fuselage or both and b) a much stronger component in itself and in its bonding to the wings and fuselage.
So far Aeroic have changed the ballast tube materials in both wings and fuselage. - Though fuselage ballast seems to be becoming less and less popular with the advent of super-skinny fuselages. Now we use a combination of carbon socks and glass to provide stiffness with strength, and sometimes a kevlar wrap too. But even a stronger ballast concentrator still depends on the bonding system, unless its actually designed to be an integral and contributing part of the structure - like a modern motorcycle engine or sportscar for example.
In the wings, the entire ballast concentrator system can be integrated with the spar - especially when using the Aeroic HSWS - and can therefore become a contributing component to overall structural integrity.
If the concentrator is situated in the fuselage, then the bonding problem becomes more serious.
Whereas in the past just a slurry of colloidal silica or even (god forbid) microbaloons and normal laminating epoxy was considered adequate for joining wings and other strutural bonding; with the emergence of smaller, slimmer more cantilevered airframe structures, that method no longer does the job.
Consequently, after some experiment, we have recently changed our bonding procedures (across the board) to industrial adhesives or home-made derivatives of them. This provides a structure that is orders of magnitude stronger and less resisitant to failure than before.
We are still messing about with this, along with a lot of other potential structural improvements.
Cheers,
Doc.
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Konrad
Very Strong User
WOW, wow and wow, thanks Charles @Pinepig . Making the podium once is a fluke, the second time is coincidence and I hope to be making the third time a trend.
I learned a lot about inland sloping. But first I'd like to thank Martin Falarski for being the CD and Scott Thomason for doing a lot of the work. I also need to thank Darrell Zaballos for taking the time to give me some much needed one on one coaching. I'd like to wish him the best of luck and out comes with his planned back surgery.
Again I benefitted from winning a lot of thermal lotteries. This is huge to my way of thinking.
Now I stated out on a bad footing. I crashed my primary racer (the 96° Redshift) earlier in the day test flying her. I was going to use my Schwing Corsa 108 as my back up. But for some reason she was very tail heavy in that I had to add 65grams of nose weight. Not knowing why, I put her aside and fell back on my glass Redshift. This proved to be the best move of the day.
I lost the line up lottery by being the first up on the pilot's rotation. I was happy I had my light ship as there was no lift! I got close to the slowest time of the race with a 72 second run in the first round. I think this was a blessing in disguise, as it freed me of any aspirations of doing well. So I was free to experiment with ship set up and flying style.
The next two rounds gave me good time for me in the 50's. I also think that because of the way I was flying at the last race a lot of folks were actually watching me. ( More out of concern for their safety than enjoyment at watching my skills).
I got a lot of suggestions telling me to smooth things down. I couldn't figure out how to do that as most of my throws were already down in the 30% area for my race trims. Darrell asked me the $1K question; what were my expo setting?
Now I come from way back when we didn't have expo options on our radios. As a result I don't like to fly with a lot of expo as it gives me the feeling that I'm about to have a servo failure. Most of my expo setting are in the 18 to 25 range. Talking with the two top pilots Darrell and Ken and other, they all have their expo in the 40 to 55 range. So going against my slow conservative nature, I made a huge change in my radio set up and upped the expo to 45, all in one step.
Well, the next rounds had my times in the low 50's and upper 40's. Also, as the plane was dancing less (from my shaking fingers) I actually felt that I had more time to place the racer where I wanted. Yes, there were times I felt rushed at these new speeds but generally the plane was staying on step and really turning hard.
Then came the magic rounds! Again Darrell told me that ballasting for inland slopes is different from ballasting at the coastal slopes. On the coastal slopes we ballast to dive through the upward air in the compression zone. On inland slopes I was told to ballast to dampen the turbulence. This generally means keeping the mass lower than what you'd expect to use on the coast. As the wind was coming up I added a bit of ballast to my Redshift. I'll have to check but I think I was still a light 2.725kg 96oz. I was rewarded with 43 second rounds. These were good times, not just for me, but the fast guys never got into the 30's.
All was not roses! As I was using my 104° Redshift I was having a bit of difficulties with my pumps. Often at the top of the climb I couldn't get the ship to do a wing over (poor rudder response*) and she would just flop forward. I got a lot of good natured ribbing for these feeble attempts at making pumps. As a result of these flopping pumps I had a few late starts.
All in all had a great time and learned a lot! It is one thing to fly an F3F racer. It is another thing to race an F3F racer. I'm just starting to become one with my ships to actually try to race. It has taken about 4 years but it has been worth the effort. Again thanks to all that where willing to take the time to tell me what to do. I hope I've graciously taken your advice.
*I've never been able to get the Redshifts to pump well. And I've never liked to pump near the cliff's edge. As a result I rarely pump in the heat of battle. But in the cold air there was nothing to loose so I tried it. To the laughter of most that were watching!
I learned a lot about inland sloping. But first I'd like to thank Martin Falarski for being the CD and Scott Thomason for doing a lot of the work. I also need to thank Darrell Zaballos for taking the time to give me some much needed one on one coaching. I'd like to wish him the best of luck and out comes with his planned back surgery.
Again I benefitted from winning a lot of thermal lotteries. This is huge to my way of thinking.
Now I stated out on a bad footing. I crashed my primary racer (the 96° Redshift) earlier in the day test flying her. I was going to use my Schwing Corsa 108 as my back up. But for some reason she was very tail heavy in that I had to add 65grams of nose weight. Not knowing why, I put her aside and fell back on my glass Redshift. This proved to be the best move of the day.
I lost the line up lottery by being the first up on the pilot's rotation. I was happy I had my light ship as there was no lift! I got close to the slowest time of the race with a 72 second run in the first round. I think this was a blessing in disguise, as it freed me of any aspirations of doing well. So I was free to experiment with ship set up and flying style.
The next two rounds gave me good time for me in the 50's. I also think that because of the way I was flying at the last race a lot of folks were actually watching me. ( More out of concern for their safety than enjoyment at watching my skills).
I got a lot of suggestions telling me to smooth things down. I couldn't figure out how to do that as most of my throws were already down in the 30% area for my race trims. Darrell asked me the $1K question; what were my expo setting?Now I come from way back when we didn't have expo options on our radios. As a result I don't like to fly with a lot of expo as it gives me the feeling that I'm about to have a servo failure. Most of my expo setting are in the 18 to 25 range. Talking with the two top pilots Darrell and Ken and other, they all have their expo in the 40 to 55 range. So going against my slow conservative nature, I made a huge change in my radio set up and upped the expo to 45, all in one step.
Well, the next rounds had my times in the low 50's and upper 40's. Also, as the plane was dancing less (from my shaking fingers) I actually felt that I had more time to place the racer where I wanted. Yes, there were times I felt rushed at these new speeds but generally the plane was staying on step and really turning hard.
Then came the magic rounds! Again Darrell told me that ballasting for inland slopes is different from ballasting at the coastal slopes. On the coastal slopes we ballast to dive through the upward air in the compression zone. On inland slopes I was told to ballast to dampen the turbulence. This generally means keeping the mass lower than what you'd expect to use on the coast. As the wind was coming up I added a bit of ballast to my Redshift. I'll have to check but I think I was still a light 2.725kg 96oz. I was rewarded with 43 second rounds. These were good times, not just for me, but the fast guys never got into the 30's.
All was not roses! As I was using my 104° Redshift I was having a bit of difficulties with my pumps. Often at the top of the climb I couldn't get the ship to do a wing over (poor rudder response*) and she would just flop forward. I got a lot of good natured ribbing for these feeble attempts at making pumps. As a result of these flopping pumps I had a few late starts.
All in all had a great time and learned a lot! It is one thing to fly an F3F racer. It is another thing to race an F3F racer. I'm just starting to become one with my ships to actually try to race. It has taken about 4 years but it has been worth the effort. Again thanks to all that where willing to take the time to tell me what to do. I hope I've graciously taken your advice.
*I've never been able to get the Redshifts to pump well. And I've never liked to pump near the cliff's edge. As a result I rarely pump in the heat of battle. But in the cold air there was nothing to loose so I tried it. To the laughter of most that were watching!
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Doc James Hammond
Very Strong User
Well done Konrad,WOW, wow and wow, thanks Charles. Making the podium once is a fluke, the second time is coincidence and I hope to be making the third time is a trend.
I learned a lot about inland sloping. But first I'd like to thank Martin Falarski for being the CD and Scott Thompson for doing a lot of the work. I also need thank Darrell Zaballos for taking the time to give me some much needed one on one coaching. I'd like to wish him the best of luck and out comes with his planned back surgery.
Again I benefitted from winning a lot of thermal lotteries. This is huge to my way of thinking.
Now I stated out on a bad footing. I crashed my primary racer (the 96° Redshift) earlier in the day test flying her. I was going to use my Schwing Corsa 108 as my back up. But for some reason she was very tail heavy in that I had to add 65grams of nose weight. Not knowing why I but her aside and fell back on my glass Redshift. This proved to be the best move of the day.
I lost the line up lottery by being the first up on the pilot's rotation. I was happy I had my light ship as there was no lift! I got close to the slowest time of the race with a 72 second run. I think this was a blessing in disguies, as it freed me of any asperations of doing well. So I was free to experiment with ship set up and flying style.
The next two rounds gave me good time for me in the low 50's. I also think that because of way I was flying at the last race a lot of folks were actually watching me. ( More out of concern for their safety than enjoyment at watching my skills).
Doc.
Konrad
Very Strong User
One would think that I'd have stopped making such stupid mistakes!.
We had a great day of inland sloping. It was a slope race rather than the thermal contests we sometimes get at the SLoT. My times were in the mid 40's and the fast guys got into the 30's.
My glass Redshift was turning well for the most part. So it looked like I might build on my success of the last few races. But on one of my landings I think I jammed a flap (wiper bind). I freed this easy enough. But I fear I didn't do a very good check as to the condition of the flap. On the next heat I had flap hang up in the full down position.
As a result of low pilot experience I crashed while trying to make it back to the landing zone. I tried cycling the flaps. I tried positive and negative loading of the wing, still the flap stayed out. Now here is where I made my mistake, I tried to fly the landing pattern as I normally would. But with a flap down at 90° there is no way I'd stay out of the rear rotor with that landing pattern.
Later I learned that I should have just pointed the ship into the wind and kept both flaps down. This would have resulted in the wind pushing the aircraft backwards over the front lip into the landing zone. Then land as I normally would. The result might have been a torn off flap or stripped servo. But the way I did it I lost both wings to delamination from the tumbling impact!
After the race I tried this full flap on the hill face landing technique with my Strega and it worked!
So as is usual for me my crash was 100% pilot error.
I have a question, what is the normal etiquette you use on the field when you see a guy in trouble? I've been trained in CRM (Cockpit Resource Management). That is if one has some information that might be helpful to the pilot in command you are obligated to share it. In this case I had a few guys tell me how I should have flown the emergency after the fact. And to that I'm thankful. Now I had a few guys say that they didn't want to distract me during the flight to tell me there was a much better way to fly the emergency. I understand the distraction part, but a stuck flap isn't an immediate emergency and as I had called out a mayday (asking for help) a tap on the shoulder would have been appreciated. I'm putting everybody on notice that if you see me screwing up please let me know, and if possible in a timely manner.
We had a great day of inland sloping. It was a slope race rather than the thermal contests we sometimes get at the SLoT. My times were in the mid 40's and the fast guys got into the 30's.
My glass Redshift was turning well for the most part. So it looked like I might build on my success of the last few races. But on one of my landings I think I jammed a flap (wiper bind). I freed this easy enough. But I fear I didn't do a very good check as to the condition of the flap. On the next heat I had flap hang up in the full down position.
As a result of low pilot experience I crashed while trying to make it back to the landing zone. I tried cycling the flaps. I tried positive and negative loading of the wing, still the flap stayed out. Now here is where I made my mistake, I tried to fly the landing pattern as I normally would. But with a flap down at 90° there is no way I'd stay out of the rear rotor with that landing pattern.
Later I learned that I should have just pointed the ship into the wind and kept both flaps down. This would have resulted in the wind pushing the aircraft backwards over the front lip into the landing zone. Then land as I normally would. The result might have been a torn off flap or stripped servo. But the way I did it I lost both wings to delamination from the tumbling impact!
After the race I tried this full flap on the hill face landing technique with my Strega and it worked!
So as is usual for me my crash was 100% pilot error.
I have a question, what is the normal etiquette you use on the field when you see a guy in trouble? I've been trained in CRM (Cockpit Resource Management). That is if one has some information that might be helpful to the pilot in command you are obligated to share it. In this case I had a few guys tell me how I should have flown the emergency after the fact. And to that I'm thankful. Now I had a few guys say that they didn't want to distract me during the flight to tell me there was a much better way to fly the emergency. I understand the distraction part, but a stuck flap isn't an immediate emergency and as I had called out a mayday (asking for help) a tap on the shoulder would have been appreciated. I'm putting everybody on notice that if you see me screwing up please let me know, and if possible in a timely manner.
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That could be a lot of tapping on your shoulder...I'm putting everybody on notice that if you see me screwing up please let me know, and if possible in a timely manner.
Regardless of what I do, it was probably the wrong thing to do for any given pilot. Sometimes I stay quiet, sometimes I shout..
At Sunset I will yell to clear the landing area when I think someone is about to land something that might be a dramatic landing. One less thing for a pilot to worry about.
Doc James Hammond
Very Strong User
Sorry to hear the Greenie met its end Konrad. The first one out ofthe moulds, that ws a historical model, actually. Maybe you should preserve a bit of it for posterity.
If I can, I always land full flaps into wind at the edge of the slope just a bit away from the pilots flying. Its easy to control and as long as its not too close its ultra slow - you can back up easily - parachute down and its really controllable.
Doc.
If I can, I always land full flaps into wind at the edge of the slope just a bit away from the pilots flying. Its easy to control and as long as its not too close its ultra slow - you can back up easily - parachute down and its really controllable.
Doc.
Konrad
Very Strong User
That's exactly what I should have done!
While I was down at the airplane morgue writing my corner's report I notice a faint pulse! She is now in the ICU!
Much to my surprise it looks like most of the pieces will fit together without the need of molds or extra tooling. It looks like again the hardest part of this repair will be the hinging! With the use of 3M 5300 adhesive and Doc's 3M tape I think I can be flying this soon. All the servos are responding fine.
I was shocked at just how poorly the bond was with the sine wave web! Heck all the bonds were very poor! This should be a good example for all OEMs to do away with the thickened epoxy being used as an adhesive! Also of note was that both wings failed at the pass though for the flap push rod. This should indicate that there needs to be a secondary load path in the "rear spar". I'm thinking of maybe some added carbon in the skins above and below the pass through holes.
This is also a classic example for not trashing a model at the flying field. But to wait until you are of a cooler mind set to do your triage at home or in the work shop.
Now in my low emotional state, I did pick up a new mistress in the way of a well used Freestyler 5. She will take 2 or 3 weeks of work to get her to a state where I'd fly her. Now what shocked me was the cost of the OEM LDS. They want $50 each for these. But as I only need 2 I didn't think is was worth the effort in tearing out all 4.
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Doc James Hammond
Very Strong User
That pic of the wings together is quite a comparison as it illustrates (to me at least) exactly how you shouldn't make wing planforms.
But its reported to be a good and popular model. I'd be interested to see how it compares to the Redshift.
Honestly I think people are really starting to realize how important the lift distribution actually is, which on the face of it is very strange as its SURELY one of the most critical components of any energy-efficient model aircaft - or for that matter full sized too.
For reference take a look at the new Magnum F3f which is being developed with Pierre Rondel - this is much more on target.
Doc.
Konrad
Very Strong User
That's why I posted it. The FreeStyler has a lot going for it but I don't think the planform is one of them. But as there has been a bit of a delay in the Redshift's replacement I had to get something to race. I'm confident that the Schwing Corsa 108 isn't it. (She is a great sport ship but not a fast racer). So I got what is working very well for most if not all the fast guys around here, a Freestyler.
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Konrad
Very Strong User
That sounds like my type of business plan, 20 hours of work that I could only bill 2 hours!
One would think that I'd have stopped making such stupid mistakes!.
We had a great day of inland sloping. It was a slope race rather than the thermal contests we sometimes get at the SLoT. My times were in the mid 40's and the fast guys got into the 30's.
I have a question, what is the normal etiquette you use on the field when you see a guy in trouble? I've been trained in CRM (Cockpit Resource Management). That is if one has some information that might be helpful to the pilot in command you are obligated to share it. In this case I had a few guys tell me how I should have flown the emergency after the fact. And to that I'm thankful. Now I had a few guys say that they didn't want to distract me during the flight to tell me there was a much better way to fly the emergency. I understand the distraction part, but a stuck flap isn't an immediate emergency and as I had called out a mayday (asking for help) a tap on the shoulder would have been appreciated. I'm putting everybody on notice that if you see me screwing up please let me know, and if possible in a timely manner.
I would have said something but it was too late when you started that downwind turn. It didn't occur to me at the time that you were going to do that. I kinda assumed that it was an obvious no-no. Trust me my inner monolog said dammit to myself when I saw you start that turn.
Next time as long as it's not absolutely critical the plane has to get down RIGHT NOW, ask for suggestions. I'm almost certain out of all of us morons at least one of us might have a semi-decent plan.
Konrad
Very Strong User
Like I said stupid move!
I had never seen anybody do the back into the face landing before. It never dawned on me to try it. After you suggested it (And thank you for that) I tried that with my Strega after the race. And it worked! I got a weird bump as I got past the lip, but other than that I was surprised at how normal the landing and flair went. I’m sure with the Redshift I’d have damaged a flap and or servo. But that’s the price of not doing a proper post landing check.
This is what is so great about F3F racing. Even after 4 years I’m still learning a lot!
I had never seen anybody do the back into the face landing before. It never dawned on me to try it. After you suggested it (And thank you for that) I tried that with my Strega after the race. And it worked! I got a weird bump as I got past the lip, but other than that I was surprised at how normal the landing and flair went. I’m sure with the Redshift I’d have damaged a flap and or servo. But that’s the price of not doing a proper post landing check.
This is what is so great about F3F racing. Even after 4 years I’m still learning a lot!
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I use this style landing a fair amount at Tic when it possible to use it. When there is a rotor to deal with, this method is not going to be reliable.
Heck, I'm pretty sure you have watched me do the same landing at Sunset. It is great fun to do there. It is also a great method for people to practice to get used to using the flaps to control the decent and ground speed.
I'll have to do some practices where I leave the flaps deployed in a single position for the majority of the landing. Be good training for a stuck flap in the future.
A stuck gap seal has killed many planes. It is not something we really practice for. Might be interesting to set up an old full house model you don't care for with some "disaster" mixes. Flip a switch and have an aileron stuck full down. Another switch for a full flap. Another switch to simulate a loss of servos in one wing. Then have a buddy throw one of the switches on you.
This could actually be a fun thing to share with other pilots. Hey fly my plane.. Tell them they are going to have a simulated failure and they need to figure it out and land. If they get into trouble turn the switch off.
Heck, I'm pretty sure you have watched me do the same landing at Sunset. It is great fun to do there. It is also a great method for people to practice to get used to using the flaps to control the decent and ground speed.
I'll have to do some practices where I leave the flaps deployed in a single position for the majority of the landing. Be good training for a stuck flap in the future.
A stuck gap seal has killed many planes. It is not something we really practice for. Might be interesting to set up an old full house model you don't care for with some "disaster" mixes. Flip a switch and have an aileron stuck full down. Another switch for a full flap. Another switch to simulate a loss of servos in one wing. Then have a buddy throw one of the switches on you.
This could actually be a fun thing to share with other pilots. Hey fly my plane.. Tell them they are going to have a simulated failure and they need to figure it out and land. If they get into trouble turn the switch off.
