Got a shock when putting my Ballistic on the scales.

[PeteStewardson]

OK so I've been considering selling my ballistic and replacing it with a TDR.

So to convince myself that the TDR is much lighter and I'll get better flight times because it's lighter I put the Ballistic on the electronic scales this morning. I couldn't see how a TDR could be that much lighter as other than a bit of carbon frame as the TDR frames look smaller, I couldn't see where the weight saving would come from.

Anyway put her on the scales... 3.4KG excluding flight packs! Damn it there goes that excuse

I knew this thing was light, but I didn't realise just how light.

So I went out this morning and dropped the throttle to 40% to see what would happen, she flies superbly at the low headspeed.

I'm finding parting the Ballistic out for a TDR very hard to justify. I think I'll stop trying and keep enjoying it

[trillian]

As we spoke about before Pete, I was running mine at just above 1500 and really liked the way it was flying. At that headspeed the average amp draws were really low so flight times could easily approach ten minutes. I just had to up the collective range, I think I had about 13.5 -14 degrees and then it had the responsive feel I wanted.

If you really want the most efficiency / longest flight times you can gear it for lower max headspeed. That's really the biggest key to longer flight times because the energy required goes up exponentially as the headspeed increases.

[PeteStewardson]

I have no idea what headspeed I'm getting at 40% as Mr Mels only goes down to 55%. What I do know is that 10 mins after flying the heli I checked the batteries with the Fusion and they were showing 41% left of my 4000mah packs. So since I flew for 5:25 that gives me 7:30 flight time possible, and that's not taking into account that the Fusion seems to be pretty inaccurate when putting the power back in.

I think that's about where I'd like it to be really, decent flight times and not wasting energy on power I don't need

[trillian]

I have no idea what headspeed I'm getting at 40% as Mr Mels only goes down to 55%. What I do know is that 10 mins after flying the heli I checked the batteries with the Fusion and they were showing 41% left of my 4000mah packs. So since I flew for 5:25 that gives me 7:30 flight time possible, and that's not taking into account that the Fusion seems to be pretty inaccurate when putting the power back in.

I think that's about where I'd like it to be really, decent flight times and not wasting energy on power I don't need

Yeah below the figures on the graph you just have to guess. I was told by someone that appears to be quite knowledgeable on such things that the speeds are still quite linear even below the 55% shown on the calculator, so I am guessing at some of mine by just getting the headspeed difference between say 55 and 60 and then subtracting below the figure for 55% accordingly.

I think on the Faifa and the TDR my idle-1 is about 50% throttle (Powerjive and Jive 80-HV) and should be giving me just over 1300 and then I have about 1450 in idle-2. Whenever I get a chance I'll have someone tacho them to see how close my guess is.

[PeteStewardson]

Hmmm so if the speeds are linear then

60% = 1981rpm
50% = 1785rpm
40% = 1589rpm
30% = 1393rpm

So I'm running around 1590rpm at the minute, I think I need to try 30%

[Zeeflyboy]

What ESC are you running?

just watch the temps if it doesn't have active freewheeling, running at 50% or below will result in a lot of excess energy being burnt off by the FETs and it could get a bit toasty. Most ESCs are happiest running at higher values like 70% or more, which is why gearing is important. Active freewheel lets you get around it somewhat though by giving the excess current a lower resistance route.

[PeteStewardson]

It's a Kontronik ESC so apparently I'm safe doing this. It came down cool at 40% after a 5:25 flight so wasn't a problem

[Planehazza]

It's a Kontronik ESC so apparently I'm safe doing this. It came down cool at 40% after a 5:25 flight so wasn't a problem

Yup the AFW takes care of that, but for peace of mind, I'd fit the heat sink as well...

[PeteStewardson]

Yup it's already got the heatsink on

[trillian]

This is a good thread from a few years ago, good reading for info about long flight times (they were going for silly long flight times, like 30 minutes! but the same principle applies). Logo 600 31 minute flight on Logo 600 SE (with video now). - Page 1

[PeteStewardson]

Yes interesting thread. I have to say I'm tempted to pick up a lower KV Pyro motor at some point and give that a try as I'm running the Kontronik very low now.

If I had the spare cash this month I've might even picked up the Rave for sale at the minute, but the price is a bit high for me at the minute.

[trillian]

I have a Scorpion HK3 4035/450 you can borrow if you'd like Pete. I had it in my ENV at first and then moved it to the Faifa for a while and now I have a rewound really low KV motor in the Faifa so it's just sitting on the shelf at the moment.

[muscleflex]

Goodness! 5mins already feels like forever to me when I fly!

[PeteStewardson]

Thanks Sheryl, will shout if I decide to give it a go, need a bit more time trying different speeds as it is first

Goodness! 5mins already feels like forever to me when I fly!

Hahaha na 5mins is not enough although you can go too far the other way. Chap at the club has a Gasser and it'll run for 45mins lol

[Planehazza]

Thanks Sheryl, will shout if I decide to give it a go, need a bit more time trying different speeds as it is first



Hahaha na 5mins is not enough although you can go too far the other way. Chap at the club has a Gasser and it'll run for 45mins lol

9 mins on my G4 is great, but any longer and I feel bad for hogging the flight line. It's almost as bad as when the WWI nitro planks are up for 20 mins...