Climb Test - 3400 ft!

OpenPPG Batch 2

Medium Tequila 4 loaded at 242 lb (max end of soaring weight range).

Between two flights on the same 6 bonka batteries, climbing at 65 amps on each ESC, total height gain was 3400 ft. Launched at 4400ft MSL.

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Could you estimate your rate of climb? Your video was too brief to offer any clue. Do you ever fly among the mountains seen in this video? Could you aid search and rescue efforts there as a spotter? I’m still trying to evaluate the capabilities of PPG for such purposes, particularly in an area with significant variation in elevation.

Climb rate was 227 feet per minute. Follow this thread for more details:

Not sure if electric would be ideal for search and rescue. I don’t think the battery would last long enough to travel to the mountain AND spend time searching. Gas powered, yeah sure!

Also the time of day that you are able to fly in the mountains is a very small window of the day, usually just a few hours in the evening.

Today I went up and cut the motor to soar these mountains which extended my flight by over an hour. But I was very limited on where I could go because not all the areas of the mountain were safe to fly near. I needed to be careful of catabatic winds from the shaded canyons and rotor from extended ridges. So you definitely cannot be very intimate with the terrain with varying elevation surrounding you.

Overall, you would need a prime flying day to fly mountain areas. It’s not often that we get the chance to fly the mountains. Upper altitude winds need to be perfect, otherwise there is risk of being blown over the mountain without penetration into the wind.

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Propellers were 22x10

22x14 would over draw amps. 22x10 will also over draw at full throttle which is ok for short bursts.

Much appreciation on the replies. I went to edit my original message after posting and accidentally deleted it…

Paul (@GliderPilot) , I think we should start a discussion about this. As a bigger guy, more than half of my flights are 100% throttle the entire flight (with 4 or 6 bonkas). By the time I land the esc is not even warm to the touch. Zack has also mentioned that the esc will handle more amps as long as it is properly cooled. Yes maybe changing props will overload the esc, but in the current config it seems to work well as designed. (for reference I only have 35 flights on my OpenPPG, but I have launched from sea level up to launches above 8000 feet).

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I agree they are well cooled and barely get warm after flight. After less then one year of flying mine I burned up a speed controller. I think the damage was caused by induction from having long wires without using extra capacitors because it burned up on the first flight where I converted from 4 to 6 batteries. However, I believe running them over the amp rating probably contributed to the wear which is why it burned up on my first 6 battery flight. Also, I had the shortest wiring possible with 4 batteries and even that wiring is too long to not have extra capacitors. Note: induction causes high voltage spikes which result in amp spikes and amps are what cause damage.

The new board that Zach just posted about will read telemetry data from the ESCs which can monitor the temperature of the FETs and capacitors in the ESCs. But then the question will be what is the recommended temperature limit for those components. Perhaps that will be answered when people share their telemetry data after having problems.

I have monitored and studied and charted amp data for quite some time now and here’s what I know: The ESCs are rated for 80 amps continuous. Full throttle with 4 batteries will draw 90 amps when fully charged and 6 batteries will draw 100 amps. This difference is because you have less voltage sag with 6 batteries and therefore more volts get to the ESCs which cause them to draw more amps. Of course you also get more thrust with higher volts and higher amps.

The instructions for the speed controllers don’t say it’s ok to exceed the limits if they are well cooled. Regardless, we are pushing them to the limits. They make a 100 amp version but it costs a lot more. If you do burn up an ESC like I did it’s only 65 dollars to replace. It might startle you when one motor starts cutting out and you will have to cut your flight short and be grounded from flying while waiting for the replacement part.

So yeah… I just explained all that just to end with: it’s not a big deal if you do burn up an ESC. Haha :joy:

Any good pilot should fly like they know their equipment is going to fail at any moment and have an alternate landing zone available at all times.

I knew you’d have some great input, thanks! Yes, the telemetry data will help us dial this in, looking forward to it! And you’re correct, I found the post that the esc is rated for 100amps burst, 80amps continuous. Burst meaning only for a few seconds, and depends on heat disapation. Not that I want to fly at my machine’s limit, but I’d like to know exactly where that limit is. :slight_smile:

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Wondering if the extra draw when going to 6 batteries could be mitigated by reducing the prop diameter a bit and making better use of the extra voltage with the slightly higher rpm for the same current draw. I’d sure sooner have a longer run time than more thrust. Thrust seems “adequate” with 4 batts.

Yes you could reduce diameter or pitch of the prop so that the ESCs can be run at full throttle which is more efficient for the ESCs but less efficient for the prop because of the higher RPM and more noisy too. Ideally you would want to use a lower KV motor instead but that’s an expensive upgrade. Batch 4 will have lower KV motors with the intent to use 14S. Won’t know the amps with batch 4 with 14S until we try it but if it draws more than 80 amps you could use 12S.