SMALL - espritmodel.com SMALL - Telemetry SMALL - Radio
Reply
Thread Tools
Old Jan 04, 2012, 02:40 AM
Registered User
yorkshire UK
Joined Oct 2007
4,252 Posts
Quote:
Originally Posted by vtdiy View Post
I get a no-load current of 0.6A and a resistance of .210 ohms.

I didn't get kV because it requires building a 3 phase rectifier, and removing the motor to a drill press.

Anyway, it doesn't look like any of the referenced motors in specs.


EDIT:

I just can't get those figures to work when I put them in Motocalc and try to predict the motor's real current consumption vs RPM on 2S and 3S batteries that I measured earlier.

So I've been adjusting the above resistance figure downwards until the prediction fits the actual measurements. (I do trust the no-load current figure).

I think the resistance may be too high above, possibly because of test lead resistance -- I hooked everything up with inexpensive alligator clip jumpers, and leads were rather long.

So, what seems to work to predict the actual draw and RPM I got is something more like the following:

1220 RPM/V
0.6A no load current
0.09 resistance

I also had to adjust the "effective" prop specs for an 11" folding prop to make it work. Folding props act like less effective non-folding props, so I adjusted the size until the speed and current predictions matched reality:

Propeller Diam 10"
Propeller Pitch 6"
P Const 1.1
T Const 0.995

With these figures, motor performance seems to mimic my and others experience. Interesting point, full throttle with 3 cells produces a motor temperature of 423 F at about 20 amps and a little over 200 watts.

Dropping that down to 65% throttle produces 6400 RPM at 90 watts (which I verified tonight) and a 500 ft/min rate of climb. 50% throttle produces 230 ft/min at 48 watts. This is for a 36 oz AUW.

2 cell performance at 100% throttle is similar to the 3 cell at 65% throttle.
good work, so 2 cells is a better option then 3 cells on the 11x7 prop, it's better because the esc will be working more efficiently at 100% I remember reading somewhere. Also on 2 cells the bec will run much cooler and have more amps avaiable to give to servos b4 getting too hot and shutting down, this is because it only needs to drop from 7.4 volts rather then 11.1v, the extra volts on 11.1v being disipated as heat, the watts disipated here are amps x volts of course.

I am surprised that on 3 cells the watts did not show more than that though, as on 3 cells with the 9x5 amp draw is 18amps in actual flight wot climbs. I wonder if the 11x7 prop is more like 11x4. The plot thickens lol.
We need some definitive info on that prop I think.
nigelsheffield is offline Find More Posts by nigelsheffield
Reply With Quote
Sign up now
to remove ads between posts
Old Jan 04, 2012, 04:32 PM
low tech high tech
vtdiy's Avatar
Southern Vermont
Joined Feb 2007
3,028 Posts
Nigel, I just tried 11x4 in Motocalc and nothing works. It says it won't even fly at all at 65% power (though the plane does quite well in reality), plus amps are too high, along with RPM compared to test. All these opposite tendencies would be difficult to reconcile to mirror actual performance, even if I adjusted the motor parameters.

If I plug in a 9x5, however, I get 17.1 amps on 3 cells, which is pretty close to what you report. Does your 9x5 measure 9" in diameter in actuality, when attached to your spinner? Incidentally, what spinner are you using? --Distance between lugs?

EDIT: Interestingly the 9x5 (three cell) amperage INCREASES slightly as plane speed increases from static, to about 17.2 A at optimum climb (19 mph). I noticed you said WOT climb, so I'm assuming you have a way of monitoring amperage in flight. My figure before were all static.
vtdiy is offline Find More Posts by vtdiy
Last edited by vtdiy; Jan 04, 2012 at 04:51 PM.
Reply With Quote
Old Jan 05, 2012, 02:47 AM
Registered User
yorkshire UK
Joined Oct 2007
4,252 Posts
Quote:
Originally Posted by vtdiy View Post
Nigel, I just tried 11x4 in Motocalc and nothing works. It says it won't even fly at all at 65% power (though the plane does quite well in reality), plus amps are too high, along with RPM compared to test. All these opposite tendencies would be difficult to reconcile to mirror actual performance, even if I adjusted the motor parameters.

If I plug in a 9x5, however, I get 17.1 amps on 3 cells, which is pretty close to what you report. Does your 9x5 measure 9" in diameter in actuality, when attached to your spinner? Incidentally, what spinner are you using? --Distance between lugs?

EDIT: Interestingly the 9x5 (three cell) amperage INCREASES slightly as plane speed increases from static, to about 17.2 A at optimum climb (19 mph). I noticed you said WOT climb, so I'm assuming you have a way of monitoring amperage in flight. My figure before were all static.
It measures 9 inches including stock spinner I think from memory but I am basing this on the ask21 which has same motor and prop and spinner so should not see why anything should not add up the same as this one given that they area same weight size and flight duration.
I am basing the 18 to 19 amps on the fact that my timer is set for 3 mins and I am using 900 to 970 or so mah, the 3 mins i start when I open throttle fully pause when turn off throttle, I do not use anything in between apart from servos and rx which will be very small mah's and in 20 mins hardly worth taking into equation.
So 2 x 900=1800mah in 6 mins which is 10c which means 18amps.
I use this method in all my motor gliders it is the best way I know of being consistant with battery usage and is also a good way of monitoring my thermaling stills, with the longer the flight the more thermaling I have done. I learned this on my asw28 which flyers from all over set their timers to the same 5 mins and competed for the longest flight, Which I managed with the stock setup with an hour and tens minutes on a 2 cell 1000mah lipo lol!
nigelsheffield is offline Find More Posts by nigelsheffield
Reply With Quote
Old Jan 06, 2012, 07:50 AM
Registered User
yorkshire UK
Joined Oct 2007
4,252 Posts
Right, I managed 3 flights with minimoa and mah consumed this time was 630mah for 2:30mins, so dont know why the other day it used 670mah, might be to do with temp/air density, flight were short though 10 mins was best cause wind coming over houses again and quite gusty.

Regarding my earlier statements about 3 cells in ask-21 on 9x5 and 18amps-that is not quite right, my timer is set to 3:20mins and today anyway my mah used was 800mah, now that only put amps at 14.4amps and assuming a volts about 10.6v only gives 153watts or so. But my batteries are well over a year old now and climbs are not as good as they were so you would get more from a fresh pack.
So the difference between 3 cells lipo on 9x5 and3 cell a123 on 10x8 is about 25 watts a123 being 128watts but the lipo climbed out slightly better but esc and motor came down hot, where as the a123 with the lower voltage everything was very cool and no waiting was required between flights for things to cool down.
So I would say that the motor is happy to deliver 130watts and more on 2 cell lipo but on 3 cells I think its at its limit at 160-180watts and for continuous flying your gonna need to limit throttle.
I really think its gonna be more efficient and run cooler on 2 cells lipo which is similar to my 3 cells a123 voltage.
Now has anyone tried flying this on 2 cells with the original 11x7 prop? I bet that would be just about right, allthough if you have been flying on 3 cells it will feel a bit weak.
If only they had given me the 11x7 prop in the first place I'm sure that would be perfect for me, but everwhere only has the smaller one in stock now, dont suppose anyone out there has one they dont want anymore and are prepared to send it to the U.K.
nigelsheffield is offline Find More Posts by nigelsheffield
Reply With Quote
Old Jan 06, 2012, 09:28 AM
low tech high tech
vtdiy's Avatar
Southern Vermont
Joined Feb 2007
3,028 Posts
If the weather is good, I will try flying 2 cells this weekend. My 2 cell batts are a couple years old, and 1500 mah. They are long, and lighter than the 1300 mah 3 cell pack I used last weekend, which means adding nose ballast to balance at the same point, and possibly a little higher AUW.

I might be able to parallel 2 of them, but might not have room in the plane for that.
vtdiy is offline Find More Posts by vtdiy
Reply With Quote
Old Jan 06, 2012, 10:04 AM
Registered User
yorkshire UK
Joined Oct 2007
4,252 Posts
Yeah, parallel 2 cell is a good idea if it fits, get long flights then! Cycled my 2300mah a123 packs again in car today and they certainly seem to be holding up, 1915mah went back in to one which was run down to less then 3 v in one cell, 1700mah into other which was run down to 3.2v in all 3 cells perfectly balanced, it they can stand the bumps and bangs in the car they should be ok in glider, I will actually be able to use 1700mah safely with a margin for error then in glider, so almost 3 times the amount I am using at the moment.
I will give a few more cycles to be sure and really run the cells in and then I will cut out foam in minimoa for them to fit. Its a shame my chargers only goes up to 5 amps which means about 22 mins recharge times as it's possible to charge these at 10amps or more but 22mins is ok as this plane should stay up for longer then that anyway on them, and the main reason I like these batts is the long lifespan and safety aspect and the fact that you can store them fully charged for as long as you like with no detrimental effect and they hardly loose any charge so are allways ready to go, mind you I use my lipos like this anyway cause I cant be done with having to mess about charging b4 I fly but its not good for lipos.
nigelsheffield is offline Find More Posts by nigelsheffield
Reply With Quote
Old Jan 07, 2012, 10:08 AM
Registered User
Galand's Avatar
Long Island, NY
Joined May 2010
1,601 Posts
Quote:
Originally Posted by vtdiy View Post
If the weather is good, I will try flying 2 cells this weekend. My 2 cell batts are a couple years old, and 1500 mAh. They are long, and lighter than the 1300 mAh 3 cell pack I used last weekend, which means adding nose ballast to balance at the same point, and possibly a little higher AUW.

I might be able to parallel 2 of them, but might not have room in the plane for that.
FWIW my setup has been like below for quite awhile and flies marvelously. I bought my Minimoa in July 2010.

Current Motor: TowerPro Brushless Outrunner 2410-08T 890kv.
http://www.hobbyking.com/hobbyking/s...?idProduct=664
It fits in the original 3-point mount using the original setscrews. Not perfectly, but it works when tightened well.
Here are the specs of my original motor:
http://www.art-tech.cn/english/Artic...?ArticleID=125
It was clearly meant to be a 2S set-up. I understand that current deliveries have a different motor but that was the original one that gave rise to the "burnt motor" syndrome on 3S.

My prop blades are the original 10x6 (or 7). Never been sure which.
My hub is one of those noseless ones which I bought to increase ventilation. However with the replacement TP2410 sticking so far out, cooling is not an issue. But I agree that it does not look so great. Hey, the original Minimoa had no prop at all!
The battery is a SkyLipo 3S 3000mAh 20/40C weighing 280g. That's overkill but I bought this battery specifically to get the needed weight in the nose (CG @ 55mm). I prefer to carry energy rather than lead.
This gives me 14 minutes at full throttle. I know that because my Tx timer is set at 14 mins and it counts down in proportion to how much throttle you give. (i.e full throttle counts down at normal seconds rate. Half throttle counts down at only half the normal rate.) Most of the flights are more than 1/2 hour. The most I ever put back in the battery was 2034mA and I don't think I went the full 14 mins on the timer.

This set-up @ WOT static draws 11.20A and delivers 127W in.
Galand is offline Find More Posts by Galand
Reply With Quote
Old Jan 07, 2012, 01:32 PM
low tech high tech
vtdiy's Avatar
Southern Vermont
Joined Feb 2007
3,028 Posts
I flew this morning because conditions were great for this time of year. Had an experienced tow line glider pilot FB with me as well and he also flew it 4 times. We did it all on 2 cells with all original gear, prop, motor, ESC, all stock. Went through 3 battery packs (1500 mah ea.). I used additional ballast in the form of a 3 cell 500 mah pack I had on hand (not connected of course).

The plane performed exactly the same at 100% throttle on 2 cells, as it had last week with 65% throttle on 3 cells.

Full throttle would cause it to nose up into a gradual power-on stall. The plane would climb on 75% throttle with less of this tendency, or you could add down elevator on full throttle to control attitude.

Adding flaps (via independent ailerons/flaperons) would tame the 100% throttle stalling tendency to a large degree, and has become the preferred way of hand-launching and landing.

It also seems to flatten out the glide but slow it down, but maybe that's subjective. We both thought it was visible today. Additionally, if you have to add throttle in a landing attempt to go around, the stalling tendency near ground is reduced with flaps already down.

The plane would definitely benefit from a little down thrust added to the existing motor. I may try to do this, but the engine access is very poor, as is. I'm thinking about adding a hatch (what a concept!) for access to the firewall.

If down thrust is added, I would recommend that a 2 cell battery of about 3000 mah @ 20C battery would be perfect match for this plane with the original 11" prop, original motor, and original ESC.

The 3000 mah pack would balance the plane well (with the included 2 metal ballast bars) and provide slightly more performance than the 1500 mah cells I used, as well as double the duration. 20C is plenty, as we are drawing about 12 amps, or not even 10C. No need for 30C or 40C batteries.

On the other hand if you use 3 cells with the original power setup, you SHOULD set a throttle limit of 65% on the transmitter for the throttle, or you risk doing a back-of-the-head loop on launch. If the plane survives that you will also run the risk of melting the plastic motor mount and burning out the ESC.

I hope HobbyKing will stop recommending 3 cells for this plane because it has caused a lot of unfortunate results for purchasers, and has given a fine plane some undeserved criticisms. Two cells is definitely proper for the plane in its original configuration, from my testing.
vtdiy is offline Find More Posts by vtdiy
Last edited by vtdiy; Jan 07, 2012 at 01:38 PM.
Reply With Quote
Old Jan 07, 2012, 05:09 PM
Registered User
THESANDMAN's Avatar
United States, NY, New York
Joined Oct 2010
1,680 Posts
Quote:
Originally Posted by Terrk View Post
Awesome video! You pretty much sold me on this! I'm planning on putting lights on it for some good night flying! But I'll put lights on the bottom AND the top
i agree i just pulled the trigger and ordered it.
THESANDMAN is offline Find More Posts by THESANDMAN
Reply With Quote
Old Jan 08, 2012, 03:45 AM
Registered User
yorkshire UK
Joined Oct 2007
4,252 Posts
Quote:
Originally Posted by vtdiy View Post
I flew this morning because conditions were great for this time of year. Had an experienced tow line glider pilot FB with me as well and he also flew it 4 times. We did it all on 2 cells with all original gear, prop, motor, ESC, all stock. Went through 3 battery packs (1500 mah ea.). I used additional ballast in the form of a 3 cell 500 mah pack I had on hand (not connected of course).

The plane performed exactly the same at 100% throttle on 2 cells, as it had last week with 65% throttle on 3 cells.

Full throttle would cause it to nose up into a gradual power-on stall. The plane would climb on 75% throttle with less of this tendency, or you could add down elevator on full throttle to control attitude.

Adding flaps (via independent ailerons/flaperons) would tame the 100% throttle stalling tendency to a large degree, and has become the preferred way of hand-launching and landing.

It also seems to flatten out the glide but slow it down, but maybe that's subjective. We both thought it was visible today. Additionally, if you have to add throttle in a landing attempt to go around, the stalling tendency near ground is reduced with flaps already down.

The plane would definitely benefit from a little down thrust added to the existing motor. I may try to do this, but the engine access is very poor, as is. I'm thinking about adding a hatch (what a concept!) for access to the firewall.

If down thrust is added, I would recommend that a 2 cell battery of about 3000 mah @ 20C battery would be perfect match for this plane with the original 11" prop, original motor, and original ESC.

The 3000 mah pack would balance the plane well (with the included 2 metal ballast bars) and provide slightly more performance than the 1500 mah cells I used, as well as double the duration. 20C is plenty, as we are drawing about 12 amps, or not even 10C. No need for 30C or 40C batteries.

On the other hand if you use 3 cells with the original power setup, you SHOULD set a throttle limit of 65% on the transmitter for the throttle, or you risk doing a back-of-the-head loop on launch. If the plane survives that you will also run the risk of melting the plastic motor mount and burning out the ESC.

I hope HobbyKing will stop recommending 3 cells for this plane because it has caused a lot of unfortunate results for purchasers, and has given a fine plane some undeserved criticisms. Two cells is definitely proper for the plane in its original configuration, from my testing.
Thanks for doing that, pretty much decides it then 2 cells lipo is definitely the way to go on the original 11x7 or is it 10x6 as galand states???????...
Along with a battery weighing in the region of 240 grams would mean no extra weight needed and long flight times.
Cant wait till my 10x6 asw28 prop set comes now as that had more thrust then the 10x8 which I am using at the moment, I will definitely be putting in the 2300mah a123 lifpo4 3 cell packs then which should weigh 210 grams for the cells plus the wires/connectors/covering should be just about right if a bit light still but I like cog to be further back then 54mm, at present mine is about 65 to 70 I think, makes turning in thermals better.
nigelsheffield is offline Find More Posts by nigelsheffield
Last edited by nigelsheffield; Jan 08, 2012 at 10:02 AM.
Reply With Quote
Old Jan 08, 2012, 10:23 AM
low tech high tech
vtdiy's Avatar
Southern Vermont
Joined Feb 2007
3,028 Posts
My prop measures 11" when it is fully extended outwards 90 degrees, mounted on the spinner.

I do not know what the geometric pitch is. I'll measure the 75% pitch angle when I have time and the pitch can be calculated from that.

However, the prop seems to "act" like a lower diameter prop in Motocalc. It isn't as important to me what the actual geometric diameter or pitch is. as it is in getting a reasonable representation of reality when run in Motocalc. "Reality" means amp draw, rpm, and model performance at different cell combinations, as observed, rather than paper figures.

If that matches, then you can reasonably predict what some proposed change is. Or understand what is going on if you have a performance problem.

Since Minimoas are available from at least two retailers, and they appear to have different props, there may be differences in the motors, etc as well. I can only speak for my own plane which was purchased 12/2011 from HobbyKing, and has a red 11" prop.

The best way to set up any other possible version is to simply temporarily put an ammeter in the plane's battery line, and gradually increase throttle until you are pulling enough current (at your combined cell voltage) to equal about 80 watts. Watts are equal to your battery's nominal voltage times your measured amperage. This will work with any prop size, and any combination of any type of cell.

While measuring this way will accommodate any size prop, bigger diameter props, swung slowly, are more efficient than smaller props swung fast on this type of plane, so if you received the original 11" prop, that's a good thing, as long as you use 2 cells, or limit throttle on 3 cells.
vtdiy is offline Find More Posts by vtdiy
Reply With Quote
Old Jan 08, 2012, 06:50 PM
low tech high tech
vtdiy's Avatar
Southern Vermont
Joined Feb 2007
3,028 Posts
I've just measured the original 11" prop with calipers:

Actual diameter 10.7"
Pitch angle at 4" (75% diameter) = 15.6 deg.
Using an online calculator, the effective pitch is therefore = 7"

I'm going back to Motocalc to see if there is some way I can make that work.

Edit:

After a lot of fiddling, the only way I can make that work is to drastically reduce the propeller's P coefficient (from "normal" of 1.3 down to 0.76) , and also adjust the motor's kV down to 1100 from the advertised 1200. Then performance does seem to again model actual amperage, RPM, and wattage measurements by myself and others on 2 and 3 cells . Here is what I am now using:

kV=1100
No load current = .6 A
Resistance 0.09

Prop Diam = 10.7
Prop Pitch = 7
P. Const. = 0.76
T. Const. =0.92

Using the above, here are the warnings for 3 cells:

Possible Power System Problems:

The full-throttle steady-state motor temperature (380F) is extremely high, which will likely damage the motor unless full-throttle is used sparingly and cooling is good (even then, damage is possible).
Current can be decreased by using fewer cells, a smaller diameter or lower pitched propeller, a higher gear ratio, or some combination of these methods.

Power System Notes:

At full-throttle and the best lift-to-drag ratio airspeed, the motor is operating approximately between its maximum efficiency current (8.3A) and its current at theoretical maximum output (58.4A). However, it is operating at only 66% efficiency, which is significantly less than its theoretical maximum efficiency (86%). Efficiency may improve at reduced throttle settings.

Possible Aerodynamic Problems:

The static pitch speed (52mph) is greater than 3 times the stall speed (15mph), which might make take-off or hand launching difficult, and is inefficient in flight unless high speeds are intended.

Here is the full assessment for 2 cells:

Power System Notes:

The full-throttle motor current at the best lift-to-drag ratio airspeed (12.2A) falls approximately between the motor's maximum efficiency current (6.9A) and its current at theoretical maximum output (39.7A), thus making effective use of the motor.

Aerodynamic Notes:

The static pitch speed (42mph) is within the range of approximately 2.5 to 3 times the model's stall speed (15mph), which is considered ideal for good performance.
With a wing loading of 11oz/sq.ft, a model of this size will have very sedate flying characteristics. It will be suitable for relaxed flying, in calm or very light wind conditions.
The static thrust (14.7oz) to weight (36.1oz) ratio is 0.41:1, which will result in medium length take-off runs, and no difficulty taking off from grass surfaces (assuming sufficiently large wheels).
At the best lift-to-drag ratio airspeed, the excess-thrust (9.1oz) to weight (36.1oz) ratio is 0.25:1, which will give strong climbs and rapid acceleration. This model will most likely readily loop from level flight, and have sufficient in-flight thrust for many aerobatic maneuvers.
vtdiy is offline Find More Posts by vtdiy
Last edited by vtdiy; Jan 08, 2012 at 08:19 PM.
Reply With Quote
Old Jan 08, 2012, 08:37 PM
low tech high tech
vtdiy's Avatar
Southern Vermont
Joined Feb 2007
3,028 Posts
Nigel, using the above and substituting your lower cell voltage, and trying a 10 x8 and a 10 x 6 prop:

10x8 (A123):

(I notice from the chart that your prop would be stalled from 0 to 9 mph airspeed -- perhaps that is why you noticed reduced thrust)

Warnings:

Possible Aerodynamic Problems:

The static pitch speed (60mph) is much greater than 3 times the stall speed (16mph), which might make take-off or hand launching very difficult, and is inefficient in flight unless very high speeds are intended.
Pitch speed can be decreased by using a lower pitched and/or larger diameter propeller, a higher gear ratio, a lower cell count, or some combination of these methods.
The diameter (10.0in) to pitch (8.0in) ratio is less than 1.5:1, which will result in reduced propeller efficiency at low speeds (the propeller is stalled). Although this is not likely to affect flying characteristics, it may make take-off or hand launching difficult.

Aerodynamic Notes:

Due to some of the potential problems listed above, this model may require an experienced pilot.
The static thrust (17.7oz) to weight (38.5oz) ratio is 0.46:1, which will result in medium length take-off runs, and no difficulty taking off from grass surfaces (assuming sufficiently large wheels).
At the best lift-to-drag ratio airspeed, the excess-thrust (12.7oz) to weight (38.5oz) ratio is 0.33:1, which will give strong climbs and rapid acceleration. This model will most likely readily loop from level flight, and have sufficient in-flight thrust for many aerobatic maneuvers.

10x6 (A123):

Power System Notes:

The full-throttle motor current at the best lift-to-drag ratio airspeed (14.2A) falls approximately between the motor's maximum efficiency current (7.9A) and its current at theoretical maximum output (52.6A), thus making effective use of the motor.

Aerodynamic Notes:

The static pitch speed (48mph) is within the range of approximately 2.5 to 3 times the model's stall speed (16mph), which is considered ideal for good performance.
With a wing loading of 11.7oz/sq.ft, a model of this size will have very sedate flying characteristics. It will be suitable for relaxed flying, in calm or very light wind conditions.
The static thrust (18.8oz) to weight (38.5oz) ratio is 0.49:1, which will result in medium length take-off runs, and no difficulty taking off from grass surfaces (assuming sufficiently large wheels).
At the best lift-to-drag ratio airspeed, the excess-thrust (12.4oz) to weight (38.5oz) ratio is 0.32:1, which will give strong climbs and rapid acceleration. This model will most likely readily loop from level flight, and have sufficient in-flight thrust for many aerobatic maneuvers.

Finally, re. heat, in these two examples with LiFe, the 10x6 will generate 29 watts of waste heat, while the 10x8 will generate 40 watts of heat.

To compare with the 11 inch prop on 2 cell LiPos: 19 watts of waste heat, while the 11 inch 3 cell heat figure is 64 watts.
vtdiy is offline Find More Posts by vtdiy
Last edited by vtdiy; Jan 08, 2012 at 08:42 PM.
Reply With Quote
Old Jan 09, 2012, 03:34 AM
Re-kitting Expert
Tarasdad's Avatar
USA, CA, California City
Joined Jul 2009
164 Posts
Would this combo be a good replacement for the stock setup?

http://www.nitroplanes.com/60p-dy-10...resccombo.html
Tarasdad is offline Find More Posts by Tarasdad
Reply With Quote
Old Jan 09, 2012, 03:35 AM
Registered User
yorkshire UK
Joined Oct 2007
4,252 Posts
Yeah the 10x8 prop will certainly be stalled in a static test and it is noticable in flight with climbs being better if I allow the plane to hold quite a bit of speed by keeping nose almost level!! The 10x6 should be much better but the 9x5 which came with minimoa is far too small to provide sufficient thrust for decent climbs apart from on a calm day and even then a climb of 1:30mins is needed to gain sufficient height for a 2 to 3 mins glide without thermals and sometimes struggles to climb at all. With the 10x8 1 min climb results in 4 mins glide but obviously used more battery power.
With the 10x6 I am hoping for and am pretty certain of getting more efficient climbs then the 10x8 but retaining the climb rate we will see..... roll on hobby king get them sent out.
I can live with the extra 10watts of wast heat over using 2 cell lipo and if climb outs are really good and motor is getting warm I can always reduce throttle settings too. Managed one flight yesterday with as28 but wind was coming over houses again lol so flight was only 15 mins and then winds picked up too much again so grounded for the forseeable future again lol. Back to playing with car in garden and heli in living room, and walking the dog in field. Thinking about selling up my planes as I hardly ever get to fly them these days with this bl***y wind lmfao.
nigelsheffield is offline Find More Posts by nigelsheffield
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion A330 70mm fans 2metre span Glong-flyer Electric Ducted Fan Jet Talk 4 Dec 20, 2010 10:43 PM
Discussion Hobbyking PnP 33 in wingspan F4U Corsair Lilbanks96 Electric Warbirds 10 Dec 12, 2010 01:10 PM
New Product 3.9m WINGSPAN COMPOSITE UAV AIRPLANE READY FOR SALE FPVistanbul UAV - Unmanned Aerial Vehicles 20 Dec 04, 2010 08:58 PM
Wanted 2metre sailplane with everything KeithP Aircraft - Sailplanes (FS/W) 11 Mar 01, 2008 04:58 PM
Discussion Cyclone Elite 10 2metre Electric Glider Pants Electric Sailplanes 4 Feb 27, 2006 07:45 AM