[paulj]

Well they have finally arrived.
Kev's and my new Stumax EDF's for our Temora Jets.
These babies will produce over 3000Watts 4.5Kg thrust
running on 8s batteries.
With that great "Turbine" like sound.
   
   
   

We are very happy chapies...

[smuzz]

Very interesting. Please take some video of these when you bench-test Paul, it would be great to see how they go!

[paulj]

Couple of additional photos
showing size comparison with the DeltaV
Habu Fan/Motor combo.
   
   

[~KevJ~]

oooh , im starting to get excited about that jet , i gotta a family of hawks to build!
i got to pull my finger out !

[gbanger]

Hey Kev/Paul
Have you guys done any research on the availability of 8S batteries.
They are very light on the ground and very expensive.
Gazz

[Skidz]

You can get 2 x 4S batteries in series and shrinktube them together or use them separately without shrinktubing them

Only rule is that the pairs should be kept together and not mixed. This is for internal resistance reasons as the batteries age (and the internal resistance changes). Paired batteries will age uniformly as their discharge (punishment while flying) will be identical.

[paulj]

I believe our idea is to use 2 x 4s batteries.
This way we can utalize existing batteries plus any future
ones that we may buy for our F86 and Sapac Hawk.

[~KevJ~]

yep matched 4s 4000-5000mah nano's

[Skidz]

Is this going to be something that can fly at the field or is it a dedicated large area plane (with longer runways etc)? Looks like some serious performance in that set-up. Suspect too "hot" for the field.

[smuzz]

Only rule is that the pairs should be kept together and not mixed. This is for internal resistance reasons as the batteries age (and the internal resistance changes). Paired batteries will age uniformly as their discharge (punishment while flying) will be identical.

Hmm - I didn't know that Dave ... interesting.
Thanks!

[~KevJ~]

Is this going to be something that can fly at the field or is it a dedicated large area plane (with longer runways etc)? Looks like some serious performance in that set-up. Suspect too "hot" for the field.

yeah its definately going to depend on what goes down on the maiden's which will not be taking place at our field
some have said with flaps and what not it will be managable but i suspect this will only be the case after quite afew flights when/if we get comfortable with them..

[Skidz]

Hmm - I didn't know that Dave ... interesting.
Thanks!

Steve, that rule really only applies when you want to look after your batteries and get maximum life. Some batteries cost $180 and some batteries cost $40. If your batteries didn't cost a king's ransom then I could imagine it being relaxed. Theoretically speaking, it is correct procedure.

The basics behind it: current flowing through a resistance creates heat. The greater the heat, the more resistance is present. As lipos age, the resistance increases. You might also note on batteries that they usually say "resistance matched" or use the symbol for resistance which is "ohm" or the Greek symbol omega. Flying them in pairs creates uniform resistance in both batteries so that flying performance (power delivery) is predictable.

When you have two different resistances (sticking two batteries in series), one could be hotter (the higher resistance) than the other (lower resistance). Power (W) = I (amps) squared x resistance. So you can see that resistance changes can create lots of heat when multiplied by current squared. You can kill a battery quick in such high power setups if one battery is doing all the work and other battery is just a heater.

[paulj]

thanks for that advice Dave.
Pretty sure we will be real careful to keep the batteries
compatable.
As far as flying at our field is concerned, well as Kev says it's going
to be a matter of seeing how comfortable we feel after a few flights.
Certainly I have bought my L39 with the idea of taking it to jet turbine
meetings where we will be flying from proper runways and have plenty of
space available. Usually this is a proper airport which has been closed for the day
to facilitate the Jet meeting.
I will of course be conducting taxi tests etc at our field

[gbanger]

Hey Steve
You know that MIG of yours.....prepare to meet your maker boy.... me and my F86 Sabre are coming for you.
   

[paulj]

What F86 would that be Gary?
Here is mine which is sitting here
all ready to maiden.
70mm Habu fan/Motor
Full Fibreglass fuselage/Balsa sheeted wings.

       
       
   

[Skidz]

Great plane Paul. Looks great. Nice finish.

[~KevJ~]

nice work dad, shes a beauty!
i cant wait to see her roll out with that fan setup im thinking it will get along nicely on 4s and being the habu setup you have the choice of throwing the 5s in whenever you want, that f86 will get up and boogey!
i love that scheme too and the intake on that eflite one is so scale.

looked at your vector vid again earlier too, i cant believe how well that thing was going with a 64 fan.. cant wait to fly her again

[gbanger]

Thats a nice looking beastie Paul.
What wingspan is it.
My little MIG maurader will be delivered tomorrow. Its a 64mm 4300kv 40amp foamy made by Freewing from Dwanes Planes. It has a 800mm wingspan and can run 4S.
Looking forward to getting the little sucker in the air if the strip ever dries out.
Then I can give Steve some Allie Attitude with altitude.
Gazz

[paulj]

Span is 860mm
Length is 900mm
Flying weight approx 1.6 Kg
All reports suggest that she is a rocket and lands HOT....

[smuzz]

Hmm - very interesting. Well, since the MiG-15 is smaller, it will be harder to hit .... that's about the only positive aspect I can think of right now. Looks like it will be great fun next time we get good flying conditions!

Dwelling more on this - I think it will mean that Junior and I will have to consider one of Mark@ExtremeRC's Wemotec microfan upgrades. Won't be able to afford it right away, but it looks like it's now an elevated priority