Go Back  RCU Forums > RC Airplanes > Aerodynamics
Reload this Page >

Will adding weight make my glider fly better in wind?

Aerodynamics Discuss the physics of flight revolving around the aerodynamics and design of aircraft.

Will adding weight make my glider fly better in wind?

Reply

Old 11-08-2018, 06:34 PM
  #1  
cjtyped
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2003
Location: Derby, KS
Posts: 351
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default Will adding weight make my glider fly better in wind?

i have a scale powered glider. Want to compete in contests, but wind affects the plane. So if I add weight but not change the CG, will this help? Any other suggestions?
TIA
cjtyped is offline  
Reply With Quote
Old 11-08-2018, 07:02 PM
  #2  
Lnewqban
 
Lnewqban's Avatar
 
Join Date: Apr 2007
Location: South Florida
Posts: 4,056
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

How does wind affect the glider?
More mass or weight increases the inertia of the plane, which means the sane force of wind induces a smaller acceleration or chage of speed (side-side and up-down).
If the mass is centered, it will not change the reaction of the glider to wind-induced rolls, yaws and pitch changes.
Increased weight also forces the plane to fly faster in order to generate increased lift to compensate, increasing the stall speed some.
Lnewqban is offline  
Reply With Quote
Old 11-08-2018, 07:28 PM
  #3  
speedracerntrixie
My Feedback: (29)
 
speedracerntrixie's Avatar
 
Join Date: Jun 2010
Location: Sacramento, CA
Posts: 6,513
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

I would like to know more about your specific glider. Also by contests are you referring to ALES?
speedracerntrixie is online now  
Reply With Quote
Old 11-09-2018, 09:15 AM
  #4  
cjtyped
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2003
Location: Derby, KS
Posts: 351
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

My plane is a Mick Reeves' designed Fournier RF-4 powered glider. It has a 10'. Wingspan. Electric powered. The usual aileron,Rudder,elevator,throttle plus a retracting belly wheel and spoilers. It came out pretty good, modeled after one in Las Cruces,NM. I know if I want to fly in contests, I need to be able to handle differing wind conditions, hence the question.
cjtyped is offline  
Reply With Quote
Old 11-09-2018, 01:35 PM
  #5  
speedracerntrixie
My Feedback: (29)
 
speedracerntrixie's Avatar
 
Join Date: Jun 2010
Location: Sacramento, CA
Posts: 6,513
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

The current ALES and F5J type sailplanes are slightly larger but average around 65 oz RTF. We usually do not start adding ballast until the wind hits about 15 mph. My ALES sailplane weighs 80 oz and I have never added ballast and have flown in 25 mph winds. I think yours is a bit heavy to start with but you also have more fuselage surface drag. Your not really going to be very competitive with what you have so I would say no to any ballast and suggest you just fly it as best you can and have fun.
speedracerntrixie is online now  
Reply With Quote
Old 11-09-2018, 06:04 PM
  #6  
cjtyped
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2003
Location: Derby, KS
Posts: 351
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

I need to clarify more. I am planning on entering Standoff Scale contests with my Fornier. That's all. I am going to try adding weights to my plane, bit by bit, according to wind conditions.
cjtyped is offline  
Reply With Quote
Old 11-09-2018, 06:38 PM
  #7  
speedracerntrixie
My Feedback: (29)
 
speedracerntrixie's Avatar
 
Join Date: Jun 2010
Location: Sacramento, CA
Posts: 6,513
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

I wouldn't bother if I were you. The main reason why weight is added to sailplanes is that it does help with penetration. What this means is that the sailplane is able to travel farther out while searching for lift in windy conditions. For your application, there would be no benifit.
speedracerntrixie is online now  
Reply With Quote
Old 11-10-2018, 04:42 AM
  #8  
Appowner
 
Join Date: Nov 2017
Posts: 815
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Originally Posted by cjtyped View Post
My plane is a Mick Reeves' designed Fournier RF-4 powered glider. It has a 10'. Wingspan. Electric powered. The usual aileron,Rudder,elevator,throttle plus a retracting belly wheel and spoilers. It came out pretty good, modeled after one in Las Cruces,NM. I know if I want to fly in contests, I need to be able to handle differing wind conditions, hence the question.


Is it the 1/3 scale or the 1/4 at 110 inch wing? I ask because you mention a 10 foot wing and the 1/3 scale on his web site is 12 foot while the 1/4 is just over 9 foot. What does it weigh now? Mick shows the 1/3rd coming in around 22-24 pounds and the 1/4 at 10. Might e-mail Mick and ask him. Go through the contacts page on his web site. He responds in a day or two.
Mick Reeves

And what kind of wind conditions are you talking about? What wind speed? Steady? Gusty? At the ground or higher up?

Adding weight to a glider/sailplane is a common practice. It improves penetration especially in rough air. Real and model both do it all the time. The full size competition guys use water ballast as do many larger models. I have a Lengionair 140 (from the 70's), 140 inch wing, which is designed with aluminum tube spars intended to carry extra weight in the form of .44 / .45 caliber lead slugs. It shows that on the plans and in the instructions.

As mentioned, you might find a need for a little higher flight speed. But being a Motor Glider, that should pose no problem. I do know Mick has really put the design through its paces doing hard loops and rolls with it so did you build it according to his plans? Keep in mind that a lump of added weight directly on the CG will focus more stress to that part of the structure. Just make sure the air frame is up to it. And it will float forever on final if your idle is set too high. But yours being electric shouldn't have that problem.

Depending on the scale you have, I'd say add some weight and see how it goes. Just a bit to start with. Then work up to what suits you. But again, contact Mick. I have no doubt he will respond with some interesting info on the design.

Last edited by Appowner; 11-10-2018 at 04:44 AM.
Appowner is offline  
Reply With Quote
Old 11-10-2018, 07:19 AM
  #9  
speedracerntrixie
My Feedback: (29)
 
speedracerntrixie's Avatar
 
Join Date: Jun 2010
Location: Sacramento, CA
Posts: 6,513
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

To be honest, after watching this video I would not consider it a sailplane by any definition. IMO there is not going to be any benifit to increasing the wing loading of an airplane that already has a high wing loading.

speedracerntrixie is online now  
Reply With Quote
Old 11-10-2018, 07:25 AM
  #10  
speedracerntrixie
My Feedback: (29)
 
speedracerntrixie's Avatar
 
Join Date: Jun 2010
Location: Sacramento, CA
Posts: 6,513
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

This is a much better example of a powered sailplane.

speedracerntrixie is online now  
Reply With Quote
Old 11-10-2018, 08:43 AM
  #11  
Propworn
My Feedback: (3)
 
Propworn's Avatar
 
Join Date: Jul 2002
Location: Canada
Posts: 1,765
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

You guys need read the ops posts. He is not competing in an actual sailplane event such as time, task etc. but wants to compete in a scale competition. Since scale judging has a requirement called realism he is probably concerned with penetration so scale flight in less than ideal wind conditions can still be simulated. In this case ballast will be the answer but you need to try this with little or no wind up 3 mistakes high and discover what if any are the changes in stall and flight characteristics. By all means add weight in smaller amounts until you reach a comfortable medium. I have a hanger nine Pawnee of the first generation that was so lightly wing loaded that it was difficult to land in anything but a light wind. The flaps actually made it worse. I tried moving the CofG but that did little to smooth the plane out at low speeds on landing. I found that filling the wing tube with a lb and a half of lead right on the CofG settled the plane down and now it lands perfectly in breezy conditions and has become my new loaner plane for visiting pilots.

We also have a small man made hill locally that can be sloped but only when the wind is right on the hill, brisk and steady. I bring my Sophisticated Lady and Gentle Lady and with ballast they are able to handle the wind without getting blown over the top. You have to be ready to ballast to the conditions and live with the changes in performance.



Dennis
Propworn is online now  
Reply With Quote
Old 11-10-2018, 09:19 AM
  #12  
speedracerntrixie
My Feedback: (29)
 
speedracerntrixie's Avatar
 
Join Date: Jun 2010
Location: Sacramento, CA
Posts: 6,513
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Sorry but we have had this discussion before and you know that I just don't agree. Having a powered airplane that copes with the wind well has more to do with the setup then wing loading. The subject airplane in this thread is a powered airplane with a pseudo sailplane wing. Wind is nothing more then airspeed increase to an airplane in flight. If your airplane is set up to have different trim settings at different air speeds then yes wind is going to be an issue. Will more weight help the situation? In a bandaid sort of way yes. It will take more wind force to make a change but it will also require larger control inputs to correct. Once an airplane is set up so that the CG, thrust line, incidence control throws, differential etc are all in balance the airplane will handle the wind much better. Adding weight on a powered airplane is nothing more then a coverup to a bad setup. Case in point, on a dual aileron servo setup, how many guys take the time to actually measure the aileron movement and go into the separate channel ATV and adjust them for the exact same deflection? Most times when I help guys out at the field the ATV for both channels are set to the same value which means the ailerons are not moving the same. Then they rarely use the differential feature. This means that when aileron is applied the airplane will not only roll but it will pitch and yaw at the same time. Add in some wind which will require more corrective inputs that are not pure inputs and the airplane is all over the place. The key here is better setup not more weight.
speedracerntrixie is online now  
Reply With Quote
Old 11-12-2018, 09:55 AM
  #13  
Propworn
My Feedback: (3)
 
Propworn's Avatar
 
Join Date: Jul 2002
Location: Canada
Posts: 1,765
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Not agreeing doesn't make you the authority its only your opinion and you know what they say about opinions!!!!!!!!!!!!!!!!!!!!!!!!! Read the ops posts carefully and slowly if you have to. He is interested in competing in scale that means scale like flight as observed from the judges area. Sometimes the wind you are required to fly in is not scale like. Most likely the judges are wanting to see power off flight in something like a fly by, ascending or descending circle which have to be done front and center of the judges with equal and even parts before and after the judges. With a lightly loaded glider type air frame and low penetration this would not be possible without some ballast. This has nothing to do with performance and everything to do with visible representation of scale flight for the judges.

Second of all when talking performance water ballast is often used in full size sailplanes to fine tune the performance. Look up slope and dynamic soaring without ballast the performance they are achieving would not be possible and the amount is adjusted to suit the conditions.

Your statement of a lighter plane always fly's better doesn't ring true in all cases as you would lead us to believe. I have even seen guys flying the 40% in freestyle add ballast to move the CofG back a little further to increase the instability that allows some of the wilder aerobatics when they fly their freestyle routine.

Dennis
Propworn is online now  
Reply With Quote
Old 11-12-2018, 01:32 PM
  #14  
speedracerntrixie
My Feedback: (29)
 
speedracerntrixie's Avatar
 
Join Date: Jun 2010
Location: Sacramento, CA
Posts: 6,513
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Dennis, I donít claim to be an authority here on RCU. Apparently I do not use enough exclamation points to qualify as an authority. Iím just a guy who has flown all types of R/C aircraft over the past 41 years that likes to share first hand knowledge/experience.

speedracerntrixie is online now  
Reply With Quote
Old 11-12-2018, 04:02 PM
  #15  
Propworn
My Feedback: (3)
 
Propworn's Avatar
 
Join Date: Jul 2002
Location: Canada
Posts: 1,765
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Time wise my first hand knowledge/experience is very similar to yours and even though in most cases I would agree with the lighter air frame proponent you explain I have also learned that what ever the rule in this hobby there are always going to be exceptions and compromises that might be taken to accomplish a specific goal.

http://f3j.in.ua/ballasts.html

https://www.soaringusa.com/Ballast/

http://www.espritmodel.com/sailplane...-brass-14.aspx

Many many reputable companies have ballast kits available.

Dennis

Last edited by Propworn; 11-12-2018 at 04:19 PM.
Propworn is online now  
Reply With Quote
Old 11-12-2018, 04:40 PM
  #16  
speedracerntrixie
My Feedback: (29)
 
speedracerntrixie's Avatar
 
Join Date: Jun 2010
Location: Sacramento, CA
Posts: 6,513
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Dennis, I am quite aware of using ballast in sailplanes when appropriate. When I competed in the 1996 US Soaring team selection finals I had an extensive ballast kit for the two models I flew ( one of them being of my own design ). However during the entire contest I nor anyone else used ballast simply because the weather conditions we had that weekend would not support it. Fast forward to the 2016 International Slope Race here in Ca. Winds started light but as the day continued the slope lift was so strong that although I had installed all the ballast my sailplane would hold in its ballast tubes, I was rummaging through my tool box for anything I could cram into the fuselage. So I am VERY familiar with adding ballast in a sailplane in order to FLY FASTER or farther. My point is that I do not see ballast being appropriate for the subject model in this thread.

Your other example of a 40% aerobatic scale airplane doesn't relate either. Shifting the CG aft for more effective elevator and rudder authority is NOT the same as increasing wing loading. As far as overall flight performance is concerned, I scored better with my 37lb Extra 330 then I did with my 40lb Extra 330. It's a bit easier to be precise with an airplane that carries less inertia from control inputs. Example, the lighter airplane will be easier to stop on the mark at the end of a snap roll or point rolls.
speedracerntrixie is online now  
Reply With Quote
Old 11-12-2018, 06:24 PM
  #17  
Propworn
My Feedback: (3)
 
Propworn's Avatar
 
Join Date: Jul 2002
Location: Canada
Posts: 1,765
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

I hope the op comes back an lets us know if he solved the problem with the wind and what he did to rectify the problem. I know what works for me and when adding ballast is going to be an improvement. I'm satisfied with my models performance during competition and will continue to do what works for me. I also share this with any who are interested and surprising enough they seem to do well too. Heck during the 2002 World Scale Championships there were days when everyone was using ballast if they could even the control line guys were adding weight. Those days the wind was close to the max but the flight line never shut down everyone was expected to fly their round ballast or not. No I wasn't competing I was part of the organizing committee and helped/observed many scrambling to add weight while staying under the max allowed.

In the case of the 40% I never said it had anything to do with increasing the wing loading it was simply a mention that adding weight/ballast to to alter the characteristics and performance of a given air frame is quite common.

The op hasn't posted for some time and your not worth the effort or time so I'm just going to have to say I don't agree and leave it at that. Perhaps if someone else has used ballast it would be enlightening to hear what they have to say on the subject. With your permission of course LOL!

Dennis
Propworn is online now  
Reply With Quote
Old 11-12-2018, 06:50 PM
  #18  
cjtyped
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2003
Location: Derby, KS
Posts: 351
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default Response

I posted this about a week ago. Trying to prepare for next season. I am also fortunate to have several planes to choose from for competition. It sure is such an interesting hobby. I love it and always have. Will post more when I start my practice.
cjtyped is offline  
Reply With Quote
Old 11-12-2018, 07:24 PM
  #19  
speedracerntrixie
My Feedback: (29)
 
speedracerntrixie's Avatar
 
Join Date: Jun 2010
Location: Sacramento, CA
Posts: 6,513
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Good luck with it.
speedracerntrixie is online now  
Reply With Quote
Old 11-13-2018, 05:57 AM
  #20  
Appowner
 
Join Date: Nov 2017
Posts: 815
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Originally Posted by cjtyped View Post
I posted this about a week ago. Trying to prepare for next season. I am also fortunate to have several planes to choose from for competition. It sure is such an interesting hobby. I love it and always have. Will post more when I start my practice.
I've been exchanging e-mails with Mick Reeves over this thread (anyone else bother to do this?). They (Mick and his Son) do not recommend adding weight. simply for the sake of scale speed. More weight results in a need for more speed. And they suggest no more than a Kilo (2.2 pounds) for the 1/3 model.

If you decide to add weight, I'd suggest doing so in 1/4 pound increments.

Being a "Motor Glider" it will have the tendency to "show" the wind conditions a little more than a regular airplane. But that too is scale flight. Though a bit exaggerated. Been lots of discussion over the years as to whether or not that 10 mph breeze is seen by a 1/4 scale model as a 40 mph wind.

For info only, the real RF-5 (2 seat version) has a glide ratio of 20-1. About half of what the better sailplanes of the day could do. By comparison a Piper Cherokee 180 (4 seat, single engine, low wing) will do at its best, 12-1. So while the RF is not a true sailplane, it does have a leg up on the general aviation crowd when it comes to power off gliding. I have no idea what your model may do in a glide. But I suspect it does so quite nicely.

Just a side note, my Legionaire 140 (140 inch glider, 4.5 pounds empty or ballasted to 7.5) when coming at me on final. I can watch the wing flex as the fuselage bounces up and down from the varying wind currents close to the ground. And every time it's different. Does take some practice to get use to it and to deal with it. But I guess that's one difference between an average pilot and a good one.

On the flip side, my Citabria Pro (80 inch, 11 pounds) shows no flex of the wing on final. And it lands faster than the glider (as it should). Point is, two different aircraft react differently to the same conditions. Even if the difference is nothing but a few pounds weight. The real test is if the pilot can fly one as well as the other. Most I suspect can not which is why one becomes a favorite and the other doesn't. It's not the fault of the airplane but rather the pilots failure to make the transition between the two.

Last edited by Appowner; 11-13-2018 at 06:39 AM.
Appowner is offline  
Reply With Quote
Old 11-13-2018, 06:45 AM
  #21  
Propworn
My Feedback: (3)
 
Propworn's Avatar
 
Join Date: Jul 2002
Location: Canada
Posts: 1,765
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Originally Posted by cjtyped View Post
I posted this about a week ago. Trying to prepare for next season. I am also fortunate to have several planes to choose from for competition. It sure is such an interesting hobby. I love it and always have. Will post more when I start my practice.
At what level in scale are you intending to compete? I have always wanted to compete at your NATS however the timing is usually not good for me. I spent several years as scale chairman in Canada and scale is what I like to fly. At one of our scale nats the guy I was in close competition with had his engine bearings go to lunch on him first round Sat morning. I offered to take a look at it and he removed it from the plane. In a cardboard flat I took the engine apart and removed all the crank bearings. Called the local bearing company they were open till noon. Off went the wife to retrieve the bearings and the pilot proceeded to clean the parts in some fuel. The next round was at 1 pm. He had traveled a fair distance to participate and wasn't worried about the engine being repaired under field (less than ideal) conditions. It didn't take long to get it back together and the timing pin I had made the cam timing a snap. Carb had not been taken apart and the settings were as before. I set the valves so there was just barely movement when the other valve was down. He installed the engine and it fired right up. Bugger went on to beat me for second place by less than 10 points. We have remained good friends since. Like you said I love this hobby and the challenges it presents. I have been lucky enough to fly in quite a few places in the US and have met nothing but good guys and gals at every field I have been to.

Dennis

Last edited by Propworn; 11-13-2018 at 06:49 AM.
Propworn is online now  
Reply With Quote
Old 11-14-2018, 09:31 AM
  #22  
BMatthews
 
BMatthews's Avatar
 
Join Date: Oct 2002
Location: Chilliwack, BC, CANADA
Posts: 12,335
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Flying in wind can certainly lead to some extra work load. Not much you can do about roll and yaw effects due to side gusts from turbulence. But you can reduce your workload at maintaining the pitch axis if you trim the CG closer to the neutral stability point and re-trim the elevator to match the new CG. But while getting closer to neutral is good in some ways it's bad in others. So you'll want to find your own "sweet spot" for calming the effects of wind gusts vs having enough pitch stability for you to fly comfortably. I find that having the CG back even with a reduced elevator throw tends to make the model respond in a somewhat instant and nervous sort of way compared to a more trainer like CG setting. So a touch harder to fly smoothly and in a scale like manner. Perhaps some expo in addition to the reduced throw could aid with smoothing out the reaction to smaller inputs? That's something you'd want to play with. Also for flying in wind if you can SLIGHTLY reflex the ailerons and flaps to remove a bit of the airfoil's camber it might help too.

Adding weight won't really help any of these things. Increasing the wing loading is all about flying faster when it comes to gliders. Even your Fournier. But if that takes it away from looking scale like in the air then I don't see it as being an advantage. And scale models tend to already be fairly heavy. And that would seem to hold true here as well based on what Mick Reeve posted to Appowner above. And due to that it would be my last option after playing with setting the pitch trim to a value that gave me comfortable pitch handling and perhaps trying that reflexing trick. And, of course, lots of practice to learn to fly it in a manner that makes it look as scale like as practical.
BMatthews is offline  
Reply With Quote
Old 11-14-2018, 02:06 PM
  #23  
Propworn
My Feedback: (3)
 
Propworn's Avatar
 
Join Date: Jul 2002
Location: Canada
Posts: 1,765
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Originally Posted by BMatthews View Post
Flying in wind can certainly lead to some extra work load. Not much you can do about roll and yaw effects due to side gusts from turbulence. But you can reduce your workload at maintaining the pitch axis if you trim the CG closer to the neutral stability point and re-trim the elevator to match the new CG. But while getting closer to neutral is good in some ways it's bad in others. So you'll want to find your own "sweet spot" for calming the effects of wind gusts vs having enough pitch stability for you to fly comfortably. I find that having the CG back even with a reduced elevator throw tends to make the model respond in a somewhat instant and nervous sort of way compared to a more trainer like CG setting. So a touch harder to fly smoothly and in a scale like manner. Perhaps some expo in addition to the reduced throw could aid with smoothing out the reaction to smaller inputs? That's something you'd want to play with. Also for flying in wind if you can SLIGHTLY reflex the ailerons and flaps to remove a bit of the airfoil's camber it might help too.

Adding weight won't really help any of these things. Increasing the wing loading is all about flying faster when it comes to gliders. Even your Fournier. But if that takes it away from looking scale like in the air then I don't see it as being an advantage. And scale models tend to already be fairly heavy. And that would seem to hold true here as well based on what Mick Reeve posted to Appowner above. And due to that it would be my last option after playing with setting the pitch trim to a value that gave me comfortable pitch handling and perhaps trying that reflexing trick. And, of course, lots of practice to learn to fly it in a manner that makes it look as scale like as practical.


Pitch is not the issue. if anyone bothered to look up AMA Scale Rules and Judges Guidelines one would see that you are judged on 10 maneuvers all flown individually with a start and finish in straight and level flight equal distance on each side of the judges. The maneuver itself is to be centered on the judges. You call the maneuver by stating to the judges Starting Now and you finish by calling Complete. You are only judged from the time you call starting now and when you call complete. You have 12 min to complete all of your maneuvers. Each maneuver has a realism element to the score and there is a fairly hefty down grade for un-scale like flight. Each maneuver is worth 10 points and there is also 10 points for over all realism in flight for the whole set of maneuvers.

Here is the problem. In strong winds a lightly loaded air frame flying downwind will speed by the judges in a very un-scale like speed and with great difficulty may or may not be able to hold a maneuver center on the judges or make realistic headway when the maneuver calls for the model to complete the maneuver heading upwind. The same air frame might barely make realistic headway when flown upwind and get pushed downwind beyond realistic in any turning maneuver. Remember the flight is not about performance its about perception for the judges. So now a ballasted air frame though not performance oriented may fly into the wind with a more realistic looking airspeed over ground. In the case of this model if I were a judge I would expect at least one maneuver to show the subject in its glide mode with the prop stopped (the prototype feathered the prop it did not windmill) Easiest maneuver is straight flight out which by the way is one of the mandatory maneuvers but again flying downwind may not be an option but ballasted and flying upwind may make it look passable.

Competitors pick maneuvers that they can fly well and are within the flight envelope of the prototype. Better to pick a less aggressive maneuver and score well than a flashy difficult maneuver and have the judges score you low because it didn't satisfy what they were looking for. Maneuvers have to be chosen from a list published in the rule book maneuvers not listed have to be approved by the CD and judges. I wonder what the op would pick for his 5 optional maneuvers

Dennis

Last edited by Propworn; 11-14-2018 at 02:36 PM.
Propworn is online now  
Reply With Quote
Old 11-14-2018, 06:14 PM
  #24  
speedracerntrixie
My Feedback: (29)
 
speedracerntrixie's Avatar
 
Join Date: Jun 2010
Location: Sacramento, CA
Posts: 6,513
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Hmmmm the judging criteria sounds a lot like IMAC, except we get judged on the turn around maneuvers too. Pattern has no scale realizm criteria but has constant speed requirements and judged turn around maneuvers. With pattern you need to fly the entire sequence inside an airspace " box ". Neither disciplines have guys adding ballast to their airplanes. In fact, pattern has an 11 lb maximum weight limit.

I hate to tell you but with any powered model, simulating constant ground speed in the wind is much easier with a light model with lots of power.
speedracerntrixie is online now  
Reply With Quote
Old 11-15-2018, 08:50 AM
  #25  
Propworn
My Feedback: (3)
 
Propworn's Avatar
 
Join Date: Jul 2002
Location: Canada
Posts: 1,765
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Originally Posted by speedracerntrixie View Post
Hmmmm the judging criteria sounds a lot like IMAC, except we get judged on the turn around maneuvers too. Pattern has no scale realizm criteria but has constant speed requirements and judged turn around maneuvers. With pattern you need to fly the entire sequence inside an airspace " box ". Neither disciplines have guys adding ballast to their airplanes. In fact, pattern has an 11 lb maximum weight limit.


Not like IMAC at all between maneuvers if your not lined up the way you want you can call dead pass and do another go around. Prior to entering your maneuver you call it. I call mine prior to the last turn to the flight line "My next maneuver will be a LOOP" Now depending on the prototype being modeled 150 to 200 ft before center if I am positioned correctly I will announce "Starting Now" the same distance past center I will call "Complete" Judging is only between those two calls. Now a loop must be prototypical. A cub does not normally fly a loop without having to enter a bit of a dive to build up airspeed and the loop will be smaller and most likely oval shape and this is what the judges will be looking for as close to dead center as the pilot can get. WW1 aircraft may loop with or without the dive and some might actually stall at the top and fall on the back completing the loop. High performance aircraft enter the loop from straight and level and the size would depend on the prototype, jets and warbirds would have larger loops than an Edge but all of them would be expected to be round..

We have had many IMAC pilots enter scale with their IMAC planes and when they fly the maneuvers like they do in IMAC competition they do not score very well. They get upset because they score so well in IMAC but have failed to study the flight envelope of the prototype. The two have very different criteria.

Originally Posted by speedracerntrixie View Post
I hate to tell you but with any powered model, simulating constant ground speed in the wind is much easier with a light model with lots of power.

I agree in the case of a warbird, jet or high performance plane but we are talking a motor glider not an abundance of power and what about any passes or maneuvers to be done with the engine stopped and prop simulated feathered? In scale there are so many variables you have to adapt. Adding ballast isn't always the ideal answer but under the conditions the op is thinking about flying and the air frame being modeled ballast may be the answer.


Dennis

Last edited by Propworn; 11-15-2018 at 08:52 AM.
Propworn is online now  
Reply With Quote

Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service