Idea: EXTREME long distance challenge.

[zippity_doogah]

Basically have several of the guys build something to achieve longest lasting hover, flight, and acrobatics sessions for quads. I'm feeling like having a long drive with pilots in the back of a truck and drones behind them could prove to make for an interesting challenge. The hover and acrobatics would push the needle on variable throttle, and minimal voltage too.

 

[PsyBorg]

What you describe with the battery tech we have today you are looking at 4-6 minutes gentle acrobatics one and a half to two minutes if you are aggressively flying. Hovering may get over 10 minutes on an efficient set up. Some of the super long range quad flights are being done on 6 inch quads with huge batteries and still only about the 20 minute range at best. Distance wise ~2 miles out n back or MAYBE ~5 miles with a chase vehicle straight line.

This is all assuming you want to land softly and get to use your battery again and not have it burst into flames. Batteries are the bane of the hobby right now. There are some really efficient motor / prop combos though so that is progress.

 

[zippity_doogah]

Gotcha. I wanted to see them engineer things using what we have, which may mean slowing things down more and changing things up and adding some sort of switchable circuit to add additional batteries... These quads or other vehicles might not make it back!

 

[Mid7night]

I got 15 minutes out of my Gremsicle. Not hard acro, mind you, but I was cruising around above treetop level in moderate wind.

Still, like Psy says; that’s still not THAT long, when you talk about “long distance” or endurance flying.

 

[PsyBorg]

Gotcha. I wanted to see them engineer things using what we have, which may mean slowing things down more and changing things up and adding some sort of switchable circuit to add additional batteries... These quads or other vehicles might not make it back!

We tend not to do things where we don't get our gear back. A lost quad copter means it had to land some where and they don't glide well. Flying til you have exhausted battery power to the point of no control is senseless. It also has high potential to damage property or hurt some one and generally shine even more bad light on an already under stress from bad media hobby.

I get the idea for longer flight times or more distance is cool but please don't do anything dumb like flying til you run out of power and just letting the gear fall from the sky. You just make things worse for the rest of us doing things safe and proper.

 

[zippity_doogah]

We tend not to do things where we don't get our gear back. A lost quad copter means it had to land some where and they don't glide well. Flying til you have exhausted battery power to the point of no control is senseless. It also has high potential to damage property or hurt some one and generally shine even more bad light on an already under stress from bad media hobby.

I get the idea for longer flight times or more distance is cool but please don't do anything dumb like flying til you run out of power and just letting the gear fall from the sky. You just make things worse for the rest of us doing things safe and proper.

Of course not. No one is suggesting that. I see how it may have easily been misunderstood though.

Like I said at the beginning, I picture that happening on a long country road, low alt, easy line of sight from the back of a truck where you can land before battery is totally drained. I'm not saying fly high and let it drop out of the sky... That's stupid and dangerous.

Thank you for being honest with me and addressing it. Either way, it's just an idea. If it's not good, it's just that... Not good.

 

[PsyBorg]

A lot of people are experimenting with finding super effecient set ups. Even some of the pro pilots are now putting out long range flight videos.

FT has the 270 they recently designed to be very efecient for longer flight times as a chase copter. they also sent it on a fairly long range mission in another episode. Ummagawd also has been doing long range stuff with his 6 ince rewind quad. I also saw some footage from NurkFPV where he was learning long range from other pilots and documenting some of that process.

Its not a new thing to the hobby at all and is being done more and more. Like they all say the weak link in the equation is now battery performance.

I also did not want to sound like the old fart in the corner but I pretty much am the old fart in the corner and one of Flite Tests biggest things is to have as much fun as humanly possible but to do it safely and smartly. So when I see something potentially not safe I point it out.. I am probably just a little more direct then others would be.

 

[Webdragon]

You want long range, go sailplanes

 

[Hai-Lee]

The basic problem with really long range Quad operation is simply energy density. The amount of energy able to be carried is still very limited. If you had a nuclear powered Quad then the range would be virtually unlimited.

The real problem is the energy burn and the simple fact that the entire lift of the craft, (providing an equal and opposing force to gravity), is sourced directly from the total system energy. This constant energy burn places a definite time limit on the crafts ability to remain airborne. To stretch the range of a Quad it MUST travel at a fairly high speed such that the energy used for forward flight is large compared to the static energy burn. In other words to burn as much energy going forward as is possible before the lift drain uses the entire energy pool.

Due to blade drag and the requirement to burn energy to remain flying all rotorcraft are destined to be relatively short range unless they are large enough to carry a large energy store. A simple method to reduce the energy burn required to remain aloft is to add an aerodynamic lifting structure, (a wing), but this on a Quad alters it away from its original design.

When you add a larger battery the weight is increased and so is the energy required to keep flying. As for swapping batteries with other airborne craft it would be interesting as the overhead position of the rotors and the central under location of the battery would make swapping out a battery an extremely interesting problem especially when most radio systems would shut down without battery and so would the drive motors being used for lift.

A static "Squat and charge" via an umbilical cable could be used but the charge rate would need to be so high that it might either take an extremely long time to charge the flight battery whilst in the hover or there would be a severe risk of a battery failure, (Explosion or fire), due to the fast charging of a hot flight battery.

The things that you need to solve for long range flight is to increase the energy store without weight penalty, decrease the weight without reducing the energy store size, reduce the rotor drag and thereby reduce drag induced losses, fly the craft at maximum forward speed possible, or provide a device to increase the lift not directly related to the energy burn. (adding a wing or a dirigible type ballonette may remove its classification as being a Quad though).

Just my thoughts!

Have fun!