Flying time increase as a function of weight reduction?

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Has there been a study of how much flying time can be gained by reducing the weight of the P3P? I understand that information might be theoretical because it seems unlikely that the weight of the flying bird could be reduced, for instance, by a pound (.45kg).
However, assume for a minute that it would be possible to reduce the weight by a pound. The battery, motors and 'flyability' would remain virtually the same. The strength of the structure would also remain the same. In effect, the bird remains the same but weighs a pound less. How much longer could it stay aloft?
This "weight loss" is achievable, in fact I have already done it! To surprise you further I have also "removed" almost 2lbs. (.9kg) of weight and my P3P has the same qualities of a freshly unboxed aircraft.
So, my question is: How much longer, if any longer, can I expect the bird to fly? My guess is that any increase will not be linear and not be directly proportional to weight loss. I suspect that there is a time factor involved in the discharge rate and once the battery is being depleted the rate of discharge may not be solely related to work.
FWIW I am looking to get 45 minutes of flight time under particular conditions. Doable? We'll see. If you've been interested enough to read this far, send me a message and I'll tell you how I reduced the weight. Anyone could do it. In fact someone has probably already done it, I just don't know about it.
 
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removing the gimbal and camera if that is how you achieved it. Had been done.
No, the P3P has full 'as delivered' functionality, so it has the complete camera system, original battery, and yes, the props. I did find that if the props are removed the P3P will not fly at all! Must disconnect the battery or something when the props are removed. ;)
 
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Why make a thread and not go into what you did? Thanks for nothing.
 

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Absolutely weight reduction will give a flight time increase. How much depends on how you fly as much as anything else.

If all other things remain equal and you reduce weight then the motors would need to turn fewer RPM's to maintain that reduced weight which would give you increased flight time.
 
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Absolutely weight reduction will give a flight time increase. How much depends on how you fly as much as anything else.

If all other things remain equal and you reduce weight then the motors would need to turn fewer RPM's to maintain that reduced weight which would give you increased flight time.
Yes, but you can only reduce weight to a point, after that your air frame collapses on itself
 
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Almost two pounds, YYW. So it now weighs about a pound? You're having a laugh..
The battery weighs 0.8 lb, so the rest weighs a couple of ounces. OK you've strapped a bunch of party balloons to it?
 
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Why make a thread and not go into what you did? Thanks for nothing.
Just having a bit of intrigue. I WILL describe exactly what I've done this evening. I am not kidding about the 'weight' reduction. If you put my P3P on a scale you would see it weighs just under a pound less than it did in the box. I haven't flown it because I am suffering with a miserable cold and just don't feel like being outside if I don't have to be.
Hang in there, I just wanted to see if anyone was thinking outside the box.
 
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Almost two pounds, YYW. So it now weighs about a pound? You're having a laugh..
The battery weighs 0.8 lb, so the rest weighs a couple of ounces. OK you've strapped a bunch of party balloons to it?
No Alex, not having a laugh. You've sorta guessed it. I have purchased two weather balloons, one is a 4' dia balloon inflated to a little over three feet, and the other a 5' dia. balloon. I have inflated them with Helium purchased (rented cylinder) from a local industrial gas supplier. The first gives me near a 1lb weight reduction, the second near a 2 lb.
What I want to do is increase my 'hang time' so that once up in the air I can wait for just the right video shots. Of course I am going to lose some speed due to drag, but expect to retain all other aspects of a normal flight. I have attached an eye hook to the center of gravity of the top fuselage, but found that even if I am off a little the aircraft will self level by throttling the props appropriately. I can quickly disconnect the weather balloon for normal flight.
 
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Based on specs of P3P and others like P4 and Mavic, I did a calculation myself and in theory, I got about 40 min if I could shave P3P's weight down to 800 grams.
Here what I did, it could be wrong but just for fun.
P3P is 1280g, battery capacity is 68,096 mW and an ideal flight time is 25min.
So its power consumption is around 2,723.84 mW per minute.
Given we could lower its weight to 800 grams, with liner calculation, it would consume 1,702.4 mW. So total flight time would be 40 minutes.

Sent from my SGP771 using Tapatalk
 
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No Alex, not having a laugh. You've sorta guessed it. I have purchased two weather balloons, one is a 4' dia balloon inflated to a little over three feet, and the other a 5' dia. balloon. I have inflated them with Helium purchased (rented cylinder) from a local industrial gas supplier. The first gives me near a 1lb weight reduction, the second near a 2 lb.
What I want to do is increase my 'hang time' so that once up in the air I can wait for just the right video shots. Of course I am going to lose some speed due to drag, but expect to retain all other aspects of a normal flight. I have attached an eye hook to the center of gravity of the top fuselage, but found that even if I am off a little the aircraft will self level by throttling the props appropriately. I can quickly disconnect the weather balloon for normal flight.
So your lessoned the weight but increasing to drag. I think you will find if anything you may of lost flight time. But I'm interested to see how it works and the setup.
 

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I suppose if zero wind aloft you may see some flight time increase.

Introduce any wind and your gains will be quickly lost.
 
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No Alex, not having a laugh. You've sorta guessed it. I have purchased two weather balloons, one is a 4' dia balloon inflated to a little over three feet, and the other a 5' dia. balloon. I have inflated them with Helium purchased (rented cylinder) from a local industrial gas supplier. The first gives me near a 1lb weight reduction, the second near a 2 lb.
What I want to do is increase my 'hang time' so that once up in the air I can wait for just the right video shots. Of course I am going to lose some speed due to drag, but expect to retain all other aspects of a normal flight. I have attached an eye hook to the center of gravity of the top fuselage, but found that even if I am off a little the aircraft will self level by throttling the props appropriately. I can quickly disconnect the weather balloon for normal flight.
Lose some speed? I think if you apply any pitch or lift, you'll drag the balloon into the rotors.. Where does the balloon go when you release it?
 
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Lose some speed? I think if you apply any pitch or lift, you'll drag the balloon into the rotors.. Where does the balloon go when you release it?
I'm not releasing the balloon. The weight of the entire setup is still greater than the displaced air, so I can still maneuver up and down. It's just that the net effect of the balloon is to offset some of the weight in an attempt to gain longer flight time.
 
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So your lessoned the weight but increasing to drag. I think you will find if anything you may of lost flight time. But I'm interested to see how it works and the setup.
I am not interested at all in horizontal speed. What I want is a maneuverable platform for my video camera. As for the balloon into the props concern, I've got it handled. The string for the harness passes down a plastic tube about two feet long. Unless I do something stupid the balloon should stay well clear of the props. The plastic tube would have to be almost horizontal to contact the props.
No doubt about the drag factor. If I were racing from point to point that would be a deal breaker, but mostly I just want up and down, with a little horizontal. As for wind, my average wind is less than 2 mph and frankly I don't think that's a big concern.
 
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