I have now had the chance to cycle my S400 pylon packs a few times on my new Supernova. The Supernova will only cycle at slightly over 2A discharge. Packs were charged at 2A. The packs are:

1: 7x500AR, 1 year, 200+ flights (new green type)
1: 7x600AE, 1 year, 200+ flights
1: 7x600AE, 6 months, 100+ flights

All packs are spot welded and have 2mm gold connectors. They have been used to power my entire fleet of 400 stuff, but most flights have been full-bore in my Speedster designs

Results:

1: 600 mAh in, 600 out
2: 640 mAh in, 620 out
3: 620 mAh in, 600 out

As for flying qualitys, my 600's both pack more punch except for the first 15 seconds or so. The 500's used to false-peak on my old simple Graupner 7-cell charger. The Supernova tops them up nicely again.

/ Jonas

Think about it: 600mAh IN and 600mAh OUT? Jürgen

P.S.: How often do you go flying to get those numbers?

The important part is which one holds voltage the highest for the longest period of time. Try your test again with 15-17A discharge, or even at 6-7 for you Euro400 racing guys.

Dave

Yeah, 2 A does not proof anything, but the cycling feature is good to have. Petri is developing a system with Orbit and 100 W car light bulb that with 7 cells comes down quite close to 60 W as our 400 motors run. The the serial port connection, laptop, and last minute information before the heat! Petri could explain it better.

Originally posted by Dave Campbell
The important part is which one holds voltage the highest for the longest period of time. Try your test again with 15-17A discharge, or even at 6-7 for you Euro400 racing guys.

Dave

You get it to sound so wimpy, Dave. Lets get few things straight. Your 15-17A must be static current. Our 6-7A is the average IN THE AIR. We have around 10-12A static. I bet your average in the air is around 12A, unless what you are flying around the course are bricks.

So where are your voltage curves for red and green 500AR´s? I would love to compare. I fully agree that the important part is the voltage, not the highest possible, rocket roasting current...


Jonas:
Try battery coffin. My charge in -figures went up to 740-780mAh for 600AE´s.

Furthermore, get some N-3US cells and get them quick...below the reason why.

Petri,
What are the N-3US cells? Please elaborate

What are the size and weight of these N-3US cells? Where do we get them and how much do they cost? How about a website?

It's an AA-cell. Weight is 22 grams. Price is lower than 600AE.

They are Sanyo and are available from www.hoellein.com. I have been using them as RX packs for a few years now and also in Walkmans etc.

Saw them in S400 Pylon ships in Finland this summer which was a nice surprice. They are now sold here in Sweden as well and are very good for price, duration and performance.

/ Jonas

Yep, there we have the old dilemma again..how on earth do we fit them inside a stinger...OTOH, one cell could go rather back. Still we have no long-term experience of these, but seems really promising. Hey, Jaska has that unbuilt Adrenaline in his shop...I take the middle one of these! The DARK SIDE!

Originally posted by Tuomas Pietinen
Hey, Jaska has that unbuilt Adrenaline in his shop...I take the middle one of these! The DARK SIDE!

OK Tuomas, that sure is a lovely color of grey. It seems that you have a few things over there that we don't over here. I don't quite make out the brand name on that motor. What is it and what are the vital specs (weight, max cells and amps)?

Leftmost motor is a Lehner, rightmost is a Graupner and the middle one looks just like a Hacker.

PETRI WROTE:

You get it to sound so wimpy, Dave. Lets get few things straight. Your 15-17A must bestatic current. Our 6-7A is the average IN THE AIR. We have around 10-12A static. I bet your average in the air is around 12A, unless what you are flying around the course are bricks.

So where are your voltage curves for red and green 500AR´s? I would love to compare. I fully agree that the important part is the voltage, not the highest possible, rocket roasting current...

Petri: There's nothing to get straight here.. Comparing US and Euro races is like comparing 'apples and pomegranates'. They have different requirements from the batteries, and my comment was entirely to point that the numbers he gave have little value for either event.

I understand that you average 6-7A in the air, and any currents I quote for our event I have to be careful saying because someone out there will say theirs are different. In the US, there is such a difference in weather that current figures where I live may not be within 2A of somebody else. Then I have to hear about what I'm doing wrong to get these figures from someone else that might do their flying from a motor-simulation program....

I suspect that in-air current of a Rocket on good cells(i.e. current race setup) averages 14-15A on the smallest prop, 4.7-4.7. The object of zapping and matching is to keep voltage higher over the length of the charge, then all cells are 'dead'. This means that they pull pretty close to peak current for the whole run, probably within 3 amps.

Your event isn't worse or 'wimpier' than what we do here, just different. Speaking of which, if all you guys use is 6-7A, then why not use the 7.2V motor for it's efficiency advantage? You might have to prop it differently, but the full power amp draw would be right in the ballpark for your event. Then you could go back to lighter cells to turn better around the poles/be easier to fly. Both APC and Graupner have new 400 props to play with, it might be worth looking into?

Dave

Hi Jonas

It appears that your 500ar cells are actually performing quite well for their capacity. However, your 600ae are also doing well and better suit your requirements for comparable power AND longer flights.

I have been quite happy with my green 500ar's purchased last winter from Hollein. They consistently take a 540mah charge @ .7 amp. On the other hand, my two 600ae packs take just under 600 mah consistently @.7 amp.

Best Regards

Al

Originally posted by Dave Campbell

I understand that you average 6-7A in the air, and any currents I quote for our event I have to be careful saying because someone out there will say theirs are different. In the US, there is such a difference in weather that current figures where I live may not be within 2A of somebody else. Then I have to hear about what I'm doing wrong to get these figures from someone else that might do their flying from a motor-simulation program....

Yes I understand the problem

I suspect that in-air current of a Rocket on good cells(i.e. current race setup) averages 14-15A on the smallest prop, 4.7-4.7.

....Speaking of which, if all you guys use is 6-7A, then why not use the 7.2V motor for it's efficiency advantage? You might have to prop it differently, but the full power amp draw would be right in the ballpark for your event.

15A in the air? My god. No wonder motors get toasted.

(Far off topic, sorry)
Re: the 7.2V motors, althought I do not believe it would work because of too high prop blade lift coefficient required, it brings up another question I have been thinking a lot lately.

I have been thinking of propping problems in terms of F5D optimization. The little I know of the history, in F5D the motor producers have always tried to come up with highest possible revving motors to match the battery rules. That has led to a need of keeping the amps at just the level to reach the 70-80 secs duration at max speed. So the props used for 400-500W power are of ridiculously small diameter, leading to obvious efficiency and acceleration problem, at least based on what I have read of start problems and "getting on step" only after first lap or so. Moreover, prop has to be held square, i.e. pitch must not be above the diameter figure.

But what about if the key to higher speeds was not in the highest possible, insane level of RPM from the motor? Just for a reminder, F3D planes go FASTER than F5D´s with LESS rpm. I believe they have something in the range of 25.000rpm compared with 30.000-40.000 in F5D. F3D props are of higher diameter (8"?) and something between 7-8" in pitch. Of course they have more power, but they do have more drag also. If what I hear of Wimmer using old Kv.6400 motor on 9 cells is true, I don´t know if I want to be anywhere near his plane when cables are connected.

So in my limited knowledge, I would guess that an optimum lies on somewhat less rpm, which directly means more torque -> larger diameter prop -> higher square pitch. Larger diameter would mean better acceleration in start and at every turn. Perhaps even if the top speed would suffer, it would be insignificant because of reaching the (only slightly lower) top speed sooner after turns. And does the top speed suffer at all, considering we would have higher pitch?

In practical terms, perhaps the best motor for new F5D battery rules would be something like 7 turn Hacker B40 (Kv.~4200) instead of 4-5 turn Kv.6400 motor. A bit like using spd400/7,2V with 9 cells instead of spd400/6V on 7 cells.
Any thoughts?


All the best,

Petri

Hi, I¡¦m new in F5D but been flying F2A for over 15years and F3D for 8 years
So about F3D, I get with a Russian made cyclone 40 on the ground 27600 to 27800rpm, with a prop of D7.2¡¦xP6.3¡¦, I had in the past installed a rpm meter in my plan and getting about 36000rpm in the air is pretty normal, and the air speed is over 300KPH, the new nelson will even give you over 28000rpm on the ground, also the MB 40! So probably even more in the air!!
I also was flying F2A in the past and with a D76mmx5¡¦ single blade prop (no sure about the pitch but this is close to what we where using !! my memory is failing) we where getting 42000rpm in the air and getting to a speed close to 300KPH ( with 15.92M short line)
When you look at the history of F2A or F3D the higher the rpm goes the smaller the prop become and the top speed is always faster with this kind of setup. So I think F5D is the same?!!