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Old Mar 18, 2012, 06:19 PM
Hope is not a Strategy
Lojik's Avatar
Australia, VIC, Caroline Springs
Joined Apr 2011
1,475 Posts
Quote:
Originally Posted by Dionysus View Post
Thanks Mike, and you are welcome! Good luck on your HUN, I recommend you get one!

Thanks Falcon5!

That's great erh7771, glad I inspired you! I would like to see some other jets, I personally think a large foam F-105 would be a good choice, because you could make it so light, but I know it will never happen. Looking forward to their next offering for sure.

*********
I've been very cautious with my flying times, initially starting out with just 2 minutes on the timer. On a 6s 4000 pack I used 40 percent of the battery after flying 2 minutes and then landing. Next I tried 6s 5000 packs and used 30 percent after 2 minutes.


My question is, what would be a safe flight time giving enough for a go around. What do you guys generally have left in the packs?

Thanks,

Luke
You don't want to drop below 20% as it will degrade the cells, based on that usage I would probably start with a 4min flight on the 5000 packs, try to go a 4min flight on the 5k, land and see where your at, 4min should net you about 40% left

this should be enough to have some serious fun and a good buffer if you use more throttle than usual or need to go around a few times

I've flown a few of the Fly Fly series and my Fav 3 are:
F-4 Glassed with hot 8cell (looks great in the air, little hot on landings but if you build in some flaps or flapersons she is a great performer)
L-39 EPO lightened up with a 6cell system (great trainer, super floater)
BAE Hawk Glassed with hot 8cell (amazing glide, great aerobatic platform)
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Old Mar 18, 2012, 08:06 PM
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Eddie P's Avatar
United States, NV, Reno
Joined Mar 2000
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Agreed with above. For example, simple run time calculations for battery capacity for a 5500mah pack and a 60 amp "average/aggressive" draw (we might pull 80 amps or more full power but fly throttled back at times).
Run Time = 5.0AH/60AX60min = 5 minutes to a FLAT pack.
BUT we want to land at 20 percent capacity. So 20 percent off 5500mah is 4.4 amp hours available for burn.
So.. Run Time = 4.4AH/60X60min = 4.4 minutes for an average to aggressive overall amperage flight routine.
Then for our first few flights, the ultra conservative approach is use full blast amperage figures and validate what we put back into the pack.
4.4AH/80Ampsx60min = 3.3 minute maiden flight.

For me I always keep track of what I put back into the pack. I also watch the cell voltages over time. Packs that don't top off as high or packs that show lower voltage after familiar capacity use are showing signs of wear and tear - life limits approaching. I've flown past 80 percent here and there due to adrenaline, etc... I haven't seen an immediate problem for any occasional battery abuse but I'm sure it's cumulative enough to cost us $$.

There is a voltage factor here too that deals with resistance above and beyond the little math trick above. Lower amps and higher volts to get the same wattage is mathematically more efficient than high amps and low volts but I haven't spent enough time on any simple math to come up with a good factor for it. Standard "hummph" and shoulder shrug applies.
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Old Mar 19, 2012, 12:48 AM
Mil-Spec
mcgoughman's Avatar
United States, CA, Los Alamitos
Joined Mar 2008
120 Posts
Eze-Kote

All, looks like Horizon Hobbies has the Eze-Kote in stock in the US.

http://www.horizonhobby.com/webapp/w...pe=productgrid
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Old Mar 19, 2012, 01:19 AM
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jacojet's Avatar
South Africa, Free State, Sasolburg
Joined May 2010
205 Posts
Hi all,

Did not get to fly again yesterday, so no video. I have to get some paint on her today and tomorrow. I am leaving for our annual central fly-in on Wednesday, so will get some video then. The event is held from Thursday through to Sunday, so plenty of flying! 150 pilots attending!

A simple flight time calculator that I always use, and that has proven to be very accurate is to take the mah and multiply it with 7 for average throttle use, or 4 for continues full throttle, then, divide the result with the max amps you use. That will give you the seconds, divided by 60 and you get the minutes you can fly safely, leaves about 30% in the packs. Has always worked for me. ex: 5000mah x 7 = 35000 / 85amps =411.76 sec / 60 = 6.8min
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Old Mar 19, 2012, 05:25 AM
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Winston Hills, Sydney
Joined Apr 2009
170 Posts
Hi guys here is the link to the Aussie Distributor for Ese-kote.
www.christiantraders.com.au

Bought some 0.6gram Fibreglass Cloth and some lite filler also.
Postage was Au$13.50

Paul
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Old Mar 19, 2012, 07:05 AM
Hope is not a Strategy
Lojik's Avatar
Australia, VIC, Caroline Springs
Joined Apr 2011
1,475 Posts
Quote:
Originally Posted by jacojet View Post
Hi all,

Did not get to fly again yesterday, so no video. I have to get some paint on her today and tomorrow. I am leaving for our annual central fly-in on Wednesday, so will get some video then. The event is held from Thursday through to Sunday, so plenty of flying! 150 pilots attending!

A simple flight time calculator that I always use, and that has proven to be very accurate is to take the mah and multiply it with 7 for average throttle use, or 4 for continues full throttle, then, divide the result with the max amps you use. That will give you the seconds, divided by 60 and you get the minutes you can fly safely, leaves about 30% in the packs. Has always worked for me. ex: 5000mah x 7 = 35000 / 85amps =411.76 sec / 60 = 6.8min
6.9min sounds a little too long to me, give it a go but only go up in 30second increments, do a 4min flight, check %left and mah put back, then 4:30 etc till you get roughly 30% left in the pack for emergency go arounds
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Old Mar 19, 2012, 07:07 AM
Hope is not a Strategy
Lojik's Avatar
Australia, VIC, Caroline Springs
Joined Apr 2011
1,475 Posts
Quote:
Originally Posted by pauljohnston View Post
Hi guys here is the link to the Aussie Distributor for Ese-kote.
www.christiantraders.com.au

Bought some 0.6gram Fibreglass Cloth and some lite filler also.
Postage was Au$13.50

Paul
Thanks mate, not bad prices either, will keep them on favs for when I glass my next F-4
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Old Mar 19, 2012, 08:06 AM
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twang's Avatar
Australia, QLD, King Scrub
Joined Jun 2005
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Thanks Paul
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Old Mar 19, 2012, 10:14 AM
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Eddie P's Avatar
United States, NV, Reno
Joined Mar 2000
7,608 Posts
Quote:
Originally Posted by mcgoughman View Post
All, looks like Horizon Hobbies has the Eze-Kote in stock in the US.

http://www.horizonhobby.com/webapp/w...pe=productgrid
Thanks for the link. Seems a little high in $ for what you get in terms of material volume and then shipping on top. But, if we have a small job/single project I suppose it is what it is, we have to pay for a resin/polyurethane kit some where along the line. I guess after going back and forth between WBPU and laminating epoxy resin I've found the sweet spot for my personal style but there are great merits to a lot of different systems out there. A side note.... many marine stores that sell West Systems Epoxy sets will do free shipping or discount shipping, something to consider if you have several larger projects since for about $35 you can get 80 ounces of the highest quality laminating resin/alcohol mix by going that route. That's a lot of airplane material
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Old Mar 19, 2012, 03:22 PM
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Dionysus's Avatar
McQueeney TX
Joined Oct 2005
581 Posts
Thanks for the flight time and battery advice guys, really appreciate it. I have one more weekend of practice before the E-Festival in Austin!

I posted another video for those that are not tired of looking at my plane! It was last weekend and it was very windy, but I took her up anyway, check out the vid when it is done uploading to see how I did!


http://youtu.be/ZW35ILTWkQ4
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Old Mar 19, 2012, 04:48 PM
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jacojet's Avatar
South Africa, Free State, Sasolburg
Joined May 2010
205 Posts
Awesome! That is one good looking sabre! I am also trying a camo scheme.... Hope it turns out only half as good as yours!
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Old Mar 19, 2012, 05:54 PM
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United States, TX, Grand Prairie
Joined Nov 2005
5,861 Posts
Quote:
=Dionysus;21080147]Thanks for the flight time and battery advice guys, really appreciate it. I have one more weekend of practice before the E-Festival in Austin!
What are those dates again?

Quote:
...I posted another video for those that are not tired of looking at my plane! It was last weekend and it was very windy, but I took her up anyway, check out the vid when it is done uploading to see how I did!...
You've NO DOUBT brought out the planes scale detail potential and looks and it seems like it can be an easy fly even with the ordinance and tanks something that I didn't think would be.

About that pass....was this with your 6s and 1600kv\cs fan?

That pass looked like it was in the high 90s, low 80s....was it from a dive if so how high?

That pass was with ordinance too...

This model has so much potentiality, just wish they did the CG correctly

What is your AUW with ordinance again?

Thx very much for putting our imaginations to work on this model again.
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Old Mar 19, 2012, 06:23 PM
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Dionysus's Avatar
McQueeney TX
Joined Oct 2005
581 Posts
Thank you jacojet! I'm sure yours will look awesome too! Please keep us posted on your progress!

http://www.austinrc.org/index.php/events/teff

The Texas Electric Flight Festival will be March 30th and 31st, see you there!

Appreciate the compliments erh7771, thanks man.

I have the stock X-Flight engine fan combo in this bird, 1600kv motor on 6s.

I do manage my momentum when I fly, I did not make a big dive for the low pass, just a shallow one and it was with the wind. But I am very happy with the power of this set up and the price is right!

I don't know how much it weighs, but when I find out I'll post it here. Although with my glassing technique, it feels only slightly heavier than a stock one. It feels like it can take a lot more weight based on how it flies now!

You're welcome, I had a blast working on this plane and I'm very happy you enjoyed following along on the build with me!

Luke
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Old Mar 19, 2012, 11:16 PM
DELTAS RULE
corsair nut's Avatar
tehachapi, CA
Joined Jan 2006
22,816 Posts
gorgeous landing for a incredible model!!!!!! :O

looks even better with the weathering done!
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Old Mar 20, 2012, 04:10 AM
Registered User
Winston Hills, Sydney
Joined Apr 2009
170 Posts
Luke,
Can you please describe a little more about ypur airbrake mod.
Are you only using 1 servo? and where did you locate it?
Is it spring loaded in any way ? or does the servo do all the work?
What sort of hinges did you use?
thanks Paul
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